v4.7.16

Addresses #1033.

.editorconfig

@@ -4,7 +4,6 @@ root = true
 insert_final_newline = true
 charset = utf-8
 trim_trailing_whitespace = true
-insert_final_newline = true
 end_of_line = lf
 
 [*.{js,json}]

.gitignore

@@ -12,5 +12,6 @@ coverage
 dist
 .package.json
 packages/babel-runtime/*.js
+packages/babel-runtime/helpers/*.js
 packages/babel-runtime/regenerator/*.js
 lib

.travis.yml

@@ -1,7 +1,6 @@
 sudo: false
 language: node_js
 node_js:
-  - "0.10"
   - "0.12"
   - "iojs"
 

CHANGELOG.md

@@ -13,6 +13,94 @@ _Note: Gaps between patch versions are faulty/broken releases._
 
 See [CHANGELOG - 6to5](CHANGELOG-6to5.md) for the pre-4.0.0 version changelog.
 
+## 4.7.16
+
+ * **Bug Fix**
+  * Fix constructor spreading of typed arrays.
+  * Fix break/continue/return aliasing of non-loops in block scoping transformer.
+
+## 4.7.15
+
+ * **Bug Fix**
+  * Fix constructor spreading of collections.
+
+## 4.7.14
+
+ * **Bug Fix**
+  * Fix constructor spreading of `Promise`.
+ * **Internal**
+  * Deprecate remaining playground transformers and abstract references.
+
+## 4.7.13
+
+ * **Bug Fix**
+  * Handle comments on use strict directives.
+  * Fix assignment patterns with a left side pattern.
+ * **Polish**
+  * Special case `this` when doing expression memoisation.
+
+## 4.7.12
+
+ * **Bug Fix**
+  * Deprecate `playground.methodBinding`.
+
+## 4.7.11
+
+ * **Bug Fix**
+  * Fix unicode regexes stripping their unicode flag before being passed on two `regexpu`.
+
+## 4.7.10
+
+ * **Internal**
+  * Deprecate `playground.methodBinding` and `playground.objectGetterMemoization`.
+ * **Bug Fix**
+  * Fix `inputSourceMap` option. Thanks [@Rich-Harris](https://github.com/Rich-Harris)!
+
+## 4.7.9
+
+ * **Polish**
+  * Allow `inputSourceMap` to be set to `false` to skip the source map inference.
+  * Infer computed literal property names.
+ * **Bug Fix**
+  * Fix nested labeled for-ofs.
+  * Fix block scoping `break` colliding with the parent switch case.
+ * **Internal**
+  * Upgrade `acorn-babel`.
+
+## 4.7.8
+
+ * **Bug Fix**
+  * Fix computed classes not properly setting symbols.
+
+## 4.7.7
+
+ * **Bug Fix**
+  * Fix `types` API exposure.
+
+## 4.7.6
+
+ * **Bug Fix**
+  * Fix non-Identifier/Literal computed class methods.
+ * **Polish**
+  * Add a fallback if `stack` on an error is unconfigurable.
+  * Hoist `esModule` module declarations to the top of the file to handle circular dependencies better.
+
+## 4.7.5
+
+ * **Bug Fix**
+  * Don't remap` break`s to call the iterator return.
+ * **Polish**
+  * Use a different helper for computed classes for much nicer output. Also fixes a bug in symbols being non-enumerable so they wouldn't be set on the class.
+
+## 4.7.4
+
+ * **Bug Fix**
+  * Rewrite named function expressions in optional async function transformers.
+  * Hoist directives.
+  * Remove `Number` from the list of valid `runtime` constructors.
+ * **Internal**
+  * `spec.typeofSymbol` transformer has been renamed to `es6.symbols`.
+
 ## 4.7.2
 
  * **New Feature**

Makefile

@@ -8,11 +8,14 @@ BABEL_CMD = node_modules/babel/bin/babel
 
 export NODE_ENV = test
 
-.PHONY: clean test test-cov test-clean test-travis test-simple test-all test-browser publish build bootstrap publish-core publish-runtime build-core watch-core
+.PHONY: clean test test-cov test-clean test-travis test-simple test-all test-browser publish build bootstrap publish-core publish-runtime build-core watch-core build-core-test
 
 build-core:
 	node $(BABEL_CMD) src --out-dir lib --copy-files
 
+build-core-test:
+	node $(BABEL_CMD) src --out-dir lib --copy-files --auxiliary-comment "istanbul ignore next"
+
 watch-core:
 	node $(BABEL_CMD) src --out-dir lib --watch --copy-files
 
@@ -40,26 +43,19 @@ test-clean:
 	rm -rf test/tmp
 
 test:
-	$(MOCHA_CMD)
+	node $(MOCHA_CMD)
 	make test-clean
 
-test-simple:
-	# excludes test262
-	export SIMPLE_BABEL_TESTS=1; \
-	make test
-
 test-all:
 	export ALL_BABEL_TESTS=1; \
 	make test
 
 test-cov:
 	rm -rf coverage
-	export SIMPLE_BABEL_TESTS=1; \
+	make build-core-test
 	node $(ISTANBUL_CMD) $(MOCHA_CMD) --
 
-test-travis: bootstrap build
-	node $(ISTANBUL_CMD) $(MOCHA_CMD) --
-	if test -n "$$CODECLIMATE_REPO_TOKEN"; then codeclimate < coverage/lcov.info; fi
+test-travis: bootstrap build test
 
 test-browser:
 	mkdir -p dist

bin/babel-external-helpers

@@ -2,7 +2,7 @@
 
 var commander = require("commander");
 var util      = require("../lib/babel/util");
-var runtime = require("../lib/babel/build-external-helpers");
+var runtime   = require("../lib/babel/tools/build-external-helpers");
 
 commander.option("-l, --whitelist [whitelist]", "Whitelist of helpers to ONLY include", util.list);
 commander.option("-t, --output-type [type]", "Type of output (global|umd|var)", "global");

bin/babel-node

@@ -36,16 +36,380 @@ babelArgs.forEach(function(arg){
       args.unshift("--expose-gc");
       break;
 
-    case "--gc-global":
+    case "--use_strict":
+    case "--es_staging":
     case "--harmony":
-    case "--harmony-proxies":
-    case "--harmony-collections":
-    case "--harmony-generators":
-    case "--no-deprecation":
+    case "--harmony_shipping":
+    case "--harmony_modules":
+    case "--harmony_arrays":
+    case "--harmony_array_includes":
+    case "--harmony_regexps":
+    case "--harmony_arrow_functions":
+    case "--harmony_proxies":
+    case "--harmony_sloppy":
+    case "--harmony_unicode":
+    case "--harmony_tostring":
+    case "--harmony_numeric_literals":
+    case "--harmony_strings":
+    case "--harmony_scoping":
+    case "--harmony_classes":
+    case "--harmony_object_literals":
+    case "--harmony_templates":
+    case "--compiled_keyed_generic_loads":
+    case "--pretenuring_call_new":
+    case "--allocation_site_pretenuring":
+    case "--trace_pretenuring":
+    case "--trace_pretenuring_statistics":
+    case "--track_fields":
+    case "--track_double_fields":
+    case "--track_heap_object_fields":
+    case "--track_computed_fields":
+    case "--track_field_types":
+    case "--smi_binop":
+    case "--vector_ics":
+    case "--optimize_for_size":
+    case "--unbox_double_arrays":
+    case "--string_slices":
+    case "--crankshaft":
+    case "--hydrogen_filter":
+    case "--use_gvn":
+    case "--gvn_iterations":
+    case "--use_canonicalizing":
+    case "--use_inlining":
+    case "--use_escape_analysis":
+    case "--use_allocation_folding":
+    case "--use_local_allocation_folding":
+    case "--use_write_barrier_elimination":
+    case "--max_inlining_levels":
+    case "--max_inlined_source_size":
+    case "--max_inlined_nodes":
+    case "--max_inlined_nodes_cumulative":
+    case "--loop_invariant_code_motion":
+    case "--fast_math":
+    case "--collect_megamorphic_maps_from_stub_cache":
+    case "--hydrogen_stats":
+    case "--trace_check_elimination":
+    case "--trace_hydrogen":
+    case "--trace_hydrogen_filter":
+    case "--trace_hydrogen_stubs":
+    case "--trace_hydrogen_file":
+    case "--trace_phase":
+    case "--trace_inlining":
+    case "--trace_load_elimination":
+    case "--trace_store_elimination":
+    case "--trace_alloc":
+    case "--trace_all_uses":
+    case "--trace_range":
+    case "--trace_gvn":
+    case "--trace_representation":
+    case "--trace_removable_simulates":
+    case "--trace_escape_analysis":
+    case "--trace_allocation_folding":
+    case "--trace_track_allocation_sites":
+    case "--trace_migration":
+    case "--trace_generalization":
+    case "--stress_pointer_maps":
+    case "--stress_environments":
+    case "--deopt_every_n_times":
+    case "--deopt_every_n_garbage_collections":
+    case "--print_deopt_stress":
+    case "--trap_on_deopt":
+    case "--trap_on_stub_deopt":
+    case "--deoptimize_uncommon_cases":
+    case "--polymorphic_inlining":
+    case "--use_osr":
+    case "--array_bounds_checks_elimination":
+    case "--trace_bce":
+    case "--array_bounds_checks_hoisting":
+    case "--array_index_dehoisting":
+    case "--analyze_environment_liveness":
+    case "--load_elimination":
+    case "--check_elimination":
+    case "--store_elimination":
+    case "--dead_code_elimination":
+    case "--fold_constants":
+    case "--trace_dead_code_elimination":
+    case "--unreachable_code_elimination":
+    case "--trace_osr":
+    case "--stress_runs":
+    case "--lookup_sample_by_shared":
+    case "--cache_optimized_code":
+    case "--flush_optimized_code_cache":
+    case "--inline_construct":
+    case "--inline_arguments":
+    case "--inline_accessors":
+    case "--escape_analysis_iterations":
+    case "--optimize_for_in":
+    case "--concurrent_recompilation":
+    case "--job_based_recompilation":
+    case "--trace_concurrent_recompilation":
+    case "--concurrent_recompilation_queue_length":
+    case "--concurrent_recompilation_delay":
+    case "--block_concurrent_recompilation":
+    case "--concurrent_osr":
+    case "--omit_map_checks_for_leaf_maps":
+    case "--turbo_filter":
+    case "--trace_turbo":
+    case "--trace_turbo_graph":
+    case "--trace_turbo_cfg_file":
+    case "--trace_turbo_types":
+    case "--trace_turbo_scheduler":
+    case "--trace_turbo_reduction":
+    case "--trace_turbo_jt":
+    case "--turbo_asm":
+    case "--turbo_verify":
+    case "--turbo_stats":
+    case "--turbo_types":
+    case "--turbo_source_positions":
+    case "--context_specialization":
+    case "--turbo_deoptimization":
+    case "--turbo_inlining":
+    case "--turbo_inlining_intrinsics":
+    case "--trace_turbo_inlining":
+    case "--loop_assignment_analysis":
+    case "--turbo_profiling":
+    case "--turbo_reuse_spill_slots":
+    case "--turbo_delay_ssa_decon":
+    case "--turbo_move_optimization":
+    case "--turbo_jt":
+    case "--typed_array_max_size_in_heap":
+    case "--frame_count":
+    case "--interrupt_budget":
+    case "--type_info_threshold":
+    case "--generic_ic_threshold":
+    case "--self_opt_count":
+    case "--trace_opt_verbose":
+    case "--debug_code":
+    case "--code_comments":
+    case "--enable_sse3":
+    case "--enable_sse4_1":
+    case "--enable_sahf":
+    case "--enable_avx":
+    case "--enable_fma3":
+    case "--enable_vfp3":
+    case "--enable_armv7":
+    case "--enable_armv8":
+    case "--enable_neon":
+    case "--enable_sudiv":
+    case "--enable_mls":
+    case "--enable_movw_movt":
+    case "--enable_unaligned_accesses":
+    case "--enable_32dregs":
+    case "--enable_vldr_imm":
+    case "--force_long_branches":
+    case "--expose_natives_as":
+    case "--expose_debug_as":
+    case "--expose_free_buffer":
+    case "--expose_gc":
+    case "--expose_gc_as":
+    case "--expose_externalize_string":
+    case "--expose_trigger_failure":
+    case "--stack_trace_limit":
+    case "--builtins_in_stack_traces":
+    case "--disable_native_files":
+    case "--inline_new":
+    case "--trace_codegen":
+    case "--trace":
+    case "--mask_constants_with_cookie":
+    case "--lazy":
+    case "--trace_opt":
+    case "--trace_opt_stats":
+    case "--opt":
+    case "--always_opt":
+    case "--always_osr":
+    case "--prepare_always_opt":
+    case "--trace_deopt":
+    case "--trace_stub_failures":
+    case "--serialize_toplevel":
+    case "--serialize_inner":
+    case "--trace_serializer":
+    case "--min_preparse_length":
+    case "--max_opt_count":
+    case "--compilation_cache":
+    case "--cache_prototype_transitions":
+    case "--cpu_profiler_sampling_interval":
+    case "--trace_debug_json":
+    case "--trace_js_array_abuse":
+    case "--trace_external_array_abuse":
+    case "--trace_array_abuse":
+    case "--enable_liveedit":
+    case "--hard_abort":
+    case "--stack_size":
+    case "--max_stack_trace_source_length":
+    case "--always_inline_smi_code":
+    case "--min_semi_space_size":
+    case "--target_semi_space_size":
+    case "--max_semi_space_size":
+    case "--semi_space_growth_factor":
+    case "--experimental_new_space_growth_heuristic":
+    case "--max_old_space_size":
+    case "--initial_old_space_size":
+    case "--max_executable_size":
+    case "--gc_global":
+    case "--gc_interval":
+    case "--trace_gc":
+    case "--trace_gc_nvp":
+    case "--trace_gc_ignore_scavenger":
+    case "--trace_idle_notification":
+    case "--trace_idle_notification_verbose":
+    case "--print_cumulative_gc_stat":
+    case "--print_max_heap_committed":
+    case "--trace_gc_verbose":
+    case "--trace_fragmentation":
+    case "--collect_maps":
+    case "--weak_embedded_maps_in_optimized_code":
+    case "--weak_embedded_objects_in_optimized_code":
+    case "--flush_code":
+    case "--flush_code_incrementally":
+    case "--trace_code_flushing":
+    case "--age_code":
+    case "--incremental_marking":
+    case "--incremental_marking_steps":
+    case "--concurrent_sweeping":
+    case "--trace_incremental_marking":
+    case "--track_gc_object_stats":
+    case "--heap_profiler_trace_objects":
+    case "--use_idle_notification":
+    case "--use_ic":
+    case "--trace_ic":
+    case "--native_code_counters":
+    case "--always_compact":
+    case "--never_compact":
+    case "--compact_code_space":
+    case "--incremental_code_compaction":
+    case "--cleanup_code_caches_at_gc":
+    case "--use_marking_progress_bar":
+    case "--zap_code_space":
+    case "--random_seed":
+    case "--trace_weak_arrays":
+    case "--track_prototype_users":
+    case "--use_verbose_printer":
+    case "--allow_natives_syntax":
+    case "--trace_parse":
+    case "--trace_sim":
+    case "--debug_sim":
+    case "--check_icache":
+    case "--stop_sim_at":
+    case "--sim_stack_alignment":
+    case "--sim_stack_size":
+    case "--log_regs_modified":
+    case "--log_colour":
+    case "--ignore_asm_unimplemented_break":
+    case "--trace_sim_messages":
+    case "--stack_trace_on_illegal":
+    case "--abort_on_uncaught_exception":
+    case "--randomize_hashes":
+    case "--hash_seed":
+    case "--profile_deserialization":
+    case "--regexp_optimization":
+    case "--testing_bool_flag":
+    case "--testing_maybe_bool_flag":
+    case "--testing_int_flag":
+    case "--testing_float_flag":
+    case "--testing_string_flag":
+    case "--testing_prng_seed":
+    case "--testing_serialization_file":
+    case "--startup_blob":
+    case "--profile_hydrogen_code_stub_compilation":
+    case "--predictable":
+    case "--help":
+    case "--dump_counters":
+    case "--debugger":
+    case "--map_counters":
+    case "--js_arguments":
+    case "--gdbjit":
+    case "--gdbjit_full":
+    case "--gdbjit_dump":
+    case "--gdbjit_dump_filter":
+    case "--force_marking_deque_overflows":
+    case "--stress_compaction":
+    case "--log":
+    case "--log_all":
+    case "--log_api":
+    case "--log_code":
+    case "--log_gc":
+    case "--log_handles":
+    case "--log_snapshot_positions":
+    case "--log_suspect":
     case "--prof":
-    case "--throw-deprecation":
-    case "--trace-deprecation":
-    case "--use-strict":
+    case "--prof_browser_mode":
+    case "--log_regexp":
+    case "--logfile":
+    case "--logfile_per_isolate":
+    case "--ll_prof":
+    case "--perf_basic_prof":
+    case "--perf_jit_prof":
+    case "--gc_fake_mmap":
+    case "--log_internal_timer_events":
+    case "--log_timer_events":
+    case "--log_instruction_stats":
+    case "--log_instruction_file":
+    case "--log_instruction_period":
+    case "--redirect_code_traces":
+    case "--redirect_code_traces_to":
+    case "--hydrogen_track_positions":
+    case "--trace_elements_transitions":
+    case "--trace_creation_allocation_sites":
+    case "--print_code_stubs":
+    case "--test_secondary_stub_cache":
+    case "--test_primary_stub_cache":
+    case "--print_code":
+    case "--print_opt_code":
+    case "--print_unopt_code":
+    case "--print_code_verbose":
+    case "--print_builtin_code":
+    case "--sodium":
+    case "--print_all_code":
+    case "--es5_readonly":
+    case "--es52_globals":
+    case "--harmony_typeof":
+    case "--harmony_collections":
+    case "--packed_arrays":
+    case "--smi_only_arrays":
+    case "--clever_optimizations":
+    case "--use_range":
+    case "--eliminate_dead_phis":
+    case "--optimize_closures":
+    case "--loop_weight":
+    case "--opt_safe_uint32_operations":
+    case "--parallel_recompilation":
+    case "--trace_parallel_recompilation":
+    case "--parallel_recompilation_queue_length":
+    case "--experimental_profiler":
+    case "--watch_ic_patching":
+    case "--self_optimization":
+    case "--direct_self_opt":
+    case "--retry_self_opt":
+    case "--count_based_interrupts":
+    case "--interrupt_at_exit":
+    case "--weighted_back_edges":
+    case "--debug_code (generate extra code":
+    case "--enable_sse2":
+    case "--enable_cmov":
+    case "--enable_rdtsc":
+    case "--enable_vfp2":
+    case "--enable_fpu":
+    case "--stack_trace_on_abort":
+    case "--always_full_compiler":
+    case "--debugger_auto_break":
+    case "--break_on_abort":
+    case "--max_new_space_size":
+    case "--trace_external_memory":
+    case "--lazy_sweeping":
+    case "--trace_exception":
+    case "--preallocate_message_memory":
+    case "--preemption":
+    case "--extra_code":
+    case "--remote_debugger":
+    case "--debugger_agent":
+    case "--debugger_port":
+    case "--debug_compile_events":
+    case "--debug_script_collected_events":
+    case "--gdbjit":
+    case "--log_runtime":
+    case "--prof_auto":
+    case "--prof_lazy":
+    case "--sliding_state_window":
       args.unshift(arg);
       break;
 

package.json

@@ -1,7 +1,7 @@
 {
   "name": "babel",
   "description": "Turn ES6 code into readable vanilla ES5 with source maps",
-  "version": "4.7.2",
+  "version": "4.7.16",
   "author": "Sebastian McKenzie <sebmck@gmail.com>",
   "homepage": "https://babeljs.io/",
   "repository": "babel/babel",
@@ -36,7 +36,7 @@
     "test": "make test"
   },
   "dependencies": {
-    "acorn-babel": "0.11.1-37",
+    "acorn-babel": "0.11.1-38",
     "ast-types": "~0.7.0",
     "chalk": "^1.0.0",
     "chokidar": "^0.12.6",

packages/babel-runtime/package.json

@@ -1,7 +1,10 @@
 {
   "name": "babel-runtime",
   "description": "babel selfContained runtime",
-  "version": "4.7.1",
+  "version": "4.7.15",
   "repository": "babel/babel",
-  "author": "Sebastian McKenzie <sebmck@gmail.com>"
+  "author": "Sebastian McKenzie <sebmck@gmail.com>",
+  "dependencies": {
+    "core-js": "^0.6.1"
+  }
 }

packages/build-runtime.js

@@ -1,11 +1,12 @@
 "use strict";
 
-var transform    = require("../lib/babel/transformation");
-var buildHelpers = require("../lib/babel/build-helpers");
-var util         = require("../lib/babel/util");
-var fs           = require("fs");
-var t            = require("../lib/babel/types");
-var _            = require("lodash");
+var transform = require("../lib/babel/transformation");
+var each      = require("lodash/collection/each");
+var File      = require("../lib/babel/transformation/file");
+var util      = require("../lib/babel/util");
+var fs        = require("fs");
+var t         = require("../lib/babel/types");
+var _         = require("lodash");
 
 var relative = function (filename) {
   return __dirname + "/babel-runtime/" + filename;
@@ -39,22 +40,26 @@ var updatePackage = function () {
 
 var selfContainify = function (code) {
   return transform(code, {
-    optional: ["selfContained"]
+    optional: ["runtime"]
   }).code;
 };
 
-var buildHelpers2 = function () {
-  var body = util.template("self-contained-helpers-head");
-  var tree = t.program(body);
-
-  buildHelpers(body, t.identifier("helpers"));
+var buildHelper = function (helperName) {
+  var tree = t.program(
+    util.template("self-contained-helpers-head", {
+      HELPER: util.template(helperName)
+    })
+  );
 
   return transform.fromAst(tree, null, {
-    optional: ["selfContained"]
+    optional: ["runtime"]
   }).code;
 };
 
-writeFile("helpers.js", buildHelpers2());
+each(File.helpers, function (helperName) {
+  writeFile("helpers/" + helperName + ".js", buildHelper(helperName));
+});
+
 writeFile("core-js.js", readFile("core-js/library", true));
 writeFile("regenerator/index.js", readFile("regenerator-babel/runtime-module", true));
 writeFile("regenerator/runtime.js", selfContainify(readFile("regenerator-babel/runtime")));

src/babel/api/node.js

@@ -9,10 +9,12 @@ export { canCompile } from "../util";
 export { default as acorn } from "acorn-babel";
 export { default as transform } from "../transformation";
 export { default as traverse } from "../traversal";
-export { default as buildExternalHelpers } from "../build-external-helpers";
-export { default as types } from "../types";
+export { default as buildExternalHelpers } from "../tools/build-external-helpers";
 export { version } from "../../../package";
 
+import * as t from "../types";
+export { t as types };
+
 export function register(opts) {
   var callback = require("./register/node");
   if (opts != null) callback(opts);

src/babel/api/register/node.js

@@ -46,7 +46,7 @@ var compile = function (filename) {
   var opts = extend({}, transformOpts);
   resolveRc(filename, opts);
 
-  var cacheKey = `${filename}:${JSON.stringify(opts)}`;
+  var cacheKey = `${filename}:${JSON.stringify(opts)}:${babel.version}`;
 
   if (cache) {
     var cached = cache[cacheKey];

src/babel/build-helpers.js

@@ -1,15 +0,0 @@
-import File from "./transformation/file";
-import * as util from  "./util";
-import each from "lodash/collection/each";
-import t from "./types";
-
-export default function (body, namespace, whitelist = []) {
-  each(File.helpers, function (name) {
-    if (whitelist.length && whitelist.indexOf(name) === -1) return;
-
-    var key = t.identifier(t.toIdentifier(name));
-    body.push(t.expressionStatement(
-      t.assignmentExpression("=", t.memberExpression(namespace, key), util.template(name))
-    ));
-  });
-};

src/babel/detection/index.js

@@ -1,28 +0,0 @@
-import SYNTAX_KEYS from "./syntax-keys";
-import traverse from "../traversal";
-
-var visitors  = traverse.explode(require("./visitors"));
-
-export default function (ast) {
-  var stats = {
-    syntax: {},
-    builtins: {}
-  };
-
-  var detectedSyntax = function (name) {
-    stats.syntax[name] = true;
-  };
-
-  traverse(ast, {
-    enter(node, parent) {
-      if (SYNTAX_KEYS[node.type]) {
-        detectedSyntax(SYNTAX_KEYS[node.type]);
-      }
-
-      var visitor = visitors[node.type];
-      if (visitor) visitor(node, parent, detectedSyntax);
-    }
-  });
-
-  return stats;
-};

src/babel/detection/syntax-keys.json

@@ -1,84 +0,0 @@
-{
-  "ArrowFunctionExpression":   "es6.arrowFunctions",
-
-  "AwaitExpression":           "es7.asyncFunctions",
-
-  "ClassBody":                 "es6.classes",
-  "ClassDeclaration":          "es6.classes",
-  "ClassExpression":           "es6.classes",
-  "MethodDefinition":          "es6.classes",
-
-  "ComprehensionBlock":        "es7.comprehensions",
-  "ComprehensionExpression":   "es7.comprehensions",
-
-  "ForOfStatement":            "es6.forOf",
-
-  "ExportBatchSpecifier":      "es6.modules",
-  "ExportDeclaration":         "es6.modules",
-  "ExportSpecifier":           "es6.modules",
-  "ImportBatchSpecifier":      "es6.modules",
-  "ImportDeclaration":         "es6.modules",
-  "ImportSpecifier":           "es6.modules",
-
-  "ArrayPattern":              "es6.destructuring",
-  "AssignmentPattern":         "es6.destructuring",
-  "ObjectPattern":             "es6.destructuring",
-
-  "RestElement":               "es6.parameters.rest",
-
-  "SpreadElement":             "es6.spread",
-
-  "SpreadProperty":            "es7.objectSpread",
-
-  "TaggedTemplateExpression":  "es6.templateLiterals",
-  "TemplateElement":           "es6.templateLiterals",
-  "TemplateLiteral":           "es6.templateLiterals",
-
-  "VirtualPropertyExpression": "es7.abstractReferences",
-  "PrivateDeclaration":        "es7.abstractReferences",
-
-  "YieldExpression":           "es6.generators",
-
-  "AnyTypeAnnotation":           "flow",
-  "ArrayTypeAnnotation":         "flow",
-  "BooleanTypeAnnotation":       "flow",
-  "ClassProperty":               "flow",
-  "DeclareClass":                "flow",
-  "DeclareFunction":             "flow",
-  "DeclareModule":               "flow",
-  "DeclareVariable":             "flow",
-  "FunctionTypeAnnotation":      "flow",
-  "FunctionTypeParam":           "flow",
-  "GenericTypeAnnotation":       "flow",
-  "InterfaceExtends":            "flow",
-  "InterfaceDeclaration":        "flow",
-  "IntersectionTypeAnnotation":  "flow",
-  "NullableTypeAnnotation":      "flow",
-  "NumberTypeAnnotation":        "flow",
-  "StringLiteralTypeAnnotation": "flow",
-  "StringTypeAnnotation":        "flow",
-  "TupleTypeAnnotation":         "flow",
-  "TypeofTypeAnnotation":        "flow",
-  "TypeAlias":                   "flow",
-  "TypeAnnotation":              "flow",
-  "TypeParameterDeclaration":    "flow",
-  "TypeParameterInstantiation":  "flow",
-  "ObjectTypeAnnotation":        "flow",
-  "ObjectTypeCallProperty":      "flow",
-  "ObjectTypeIndexer":           "flow",
-  "ObjectTypeProperty":          "flow",
-  "QualifiedTypeIdentifier":     "flow",
-  "UnionTypeAnnotation":         "flow",
-  "VoidTypeAnnotation":          "flow",
-
-  "JSXAttribute":              "jsx",
-  "JSXClosingElement":         "jsx",
-  "JSXElement":                "jsx",
-  "JSXEmptyExpression":        "jsx",
-  "JSXExpressionContainer":    "jsx",
-  "JSXIdentifier":             "jsx",
-  "JSXMemberExpression":       "jsx",
-  "JSXNamespacedName":         "jsx",
-  "JSXOpeningElement":         "jsx",
-  "JSXSpreadAttribute":        "jsx"
-}

src/babel/detection/visitors.js

@@ -1,54 +0,0 @@
-import includes from "lodash/collection/includes";
-import t from "../types";
-
-export function AssignmentExpression(node, parent, detected) {
-  if (node.operator === "**=") {
-    detected("es6.exponentation");
-  }
-}
-
-export function BinaryExpression(node, parent, detected) {
-  if (node.operator === "**") {
-    detected("es6.exponentation");
-  }
-}
-
-export function VariableDeclaration(node, parent, detected) {
-  if (node.kind === "let" || node.kind === "const") {
-    detected("es6.blockScoping");
-  }
-
-  if (node.kind === "const") {
-    detected("es6.constants");
-  }
-}
-
-export function Property(node, parent, detected) {
-  if (node.shorthand || node.method) {
-    detected("es6.properties.shorthand");
-  }
-
-  if (node.kind === "set" || node.kind === "get") {
-    detected("es5.properties.mutators");
-  }
-
-  if (node.computed) {
-    detected("es6.properties.computed");
-  }
-}
-
-export function AssignmentPattern(node, parent, detected) {
-  if (t.isFunction(parent) && includes(parent.params, node)) {
-    detected("es6.parameters.default");
-  }
-}
-
-exports.Function = function (node, parent, detected) {
-  if (node.generator) {
-    detected("es6.generators");
-  }
-
-  if (node.async) {
-    detected("es7.asyncFunctions");
-  }
-};

src/babel/generation/generators/expressions.js

@@ -1,6 +1,6 @@
 import isInteger from "is-integer";
 import isNumber from "lodash/lang/isNumber";
-import t from "../../types";
+import * as t from "../../types";
 
 export function UnaryExpression(node, print) {
   var hasSpace = /[a-z]$/.test(node.operator);

src/babel/generation/generators/flow.js

@@ -1,4 +1,4 @@
-import t from "../../types";
+import * as t from "../../types";
 
 export function AnyTypeAnnotation() {
   this.push("any");

src/babel/generation/generators/jsx.js

@@ -1,5 +1,5 @@
 import each from "lodash/collection/each";
-import t from "../../types";
+import * as t from "../../types";
 
 export function JSXAttribute(node, print) {
   print(node.name);

src/babel/generation/generators/methods.js

@@ -1,4 +1,4 @@
-import t from "../../types";
+import * as t from "../../types";
 
 export function _params(node, print) {
   print(node.typeParameters);

src/babel/generation/generators/modules.js

@@ -1,5 +1,5 @@
 import each from "lodash/collection/each";
-import t from "../../types";
+import * as t from "../../types";
 
 export function ImportSpecifier(node, print) {
   if (t.isSpecifierDefault(node)) {

src/babel/generation/generators/statements.js

@@ -1,5 +1,5 @@
 import repeating from "repeating";
-import t from "../../types";
+import * as t from "../../types";
 
 export function WithStatement(node, print) {
   this.keyword("with");

src/babel/generation/index.js

@@ -8,7 +8,7 @@ import Buffer from "./buffer";
 import extend from "lodash/object/extend";
 import each from "lodash/collection/each";
 import n from "./node";
-import t from "../types";
+import * as t from "../types";
 
 class CodeGenerator {
   constructor(ast, opts, code) {

src/babel/generation/node/index.js

@@ -2,7 +2,7 @@ import whitespace from "./whitespace";
 import * as parens from "./parentheses";
 import each from "lodash/collection/each";
 import some from "lodash/collection/some";
-import t from "../../types";
+import * as t from "../../types";
 
 var find = function (obj, node, parent) {
   if (!obj) return;

src/babel/generation/node/parentheses.js

@@ -1,5 +1,5 @@
 import each from "lodash/collection/each";
-import t from "../../types";
+import * as t from "../../types";
 
 var PRECEDENCE = {};
 

src/babel/generation/node/whitespace.js

@@ -1,7 +1,7 @@
 import isBoolean from "lodash/lang/isBoolean";
 import each from "lodash/collection/each";
 import map from "lodash/collection/map";
-import t from "../../types";
+import * as t from "../../types";
 
 function crawl(node, state = {}) {
   if (t.isMemberExpression(node)) {

src/babel/generation/source-map.js

@@ -1,5 +1,5 @@
 import sourceMap from "source-map";
-import t from "../types";
+import * as t from "../types";
 
 export default class SourceMap {
   constructor(position, opts, code) {

src/babel/helpers/normalize-ast.js

@@ -1,4 +1,4 @@
-import t from "../types";
+import * as t from "../types";
 
 export default function (ast, comments, tokens) {
   if (ast && ast.type === "Program") {

src/babel/helpers/parse.js

@@ -40,7 +40,15 @@ export default function (opts, code, callback) {
         message += frame;
       }
 
-      if (err.stack) err.stack = err.stack.replace(err.message, message);
+      if (err.stack) {
+        var newStack = err.stack.replace(err.message, message);
+        try {
+          err.stack = newStack;
+        } catch (e) {
+          // `err.stack` may be a readonly property in some environments
+        }
+      }
+
       err.message = message;
     }
 

src/babel/messages.js

@@ -24,14 +24,10 @@ export var messages = {
   unsupportedOutputType: "Unsupported output type $1"
 };
 
-export function get(key) {
+export function get(key: String, ...args) {
   var msg = messages[key];
   if (!msg) throw new ReferenceError(`Unknown message ${JSON.stringify(key)}`);
 
-  var args = [];
-  for (var i = 1; i < arguments.length; i++) {
-    args.push(arguments[i]);
-  }
   args = parseArgs(args);
 
   return msg.replace(/\$(\d+)/g, function (str, i) {
@@ -39,7 +35,7 @@ export function get(key) {
   });
 }
 
-export function parseArgs(args) {
+export function parseArgs(args: Array<any>) {
   return args.map(function (val) {
     if (val != null && val.inspect) {
       return val.inspect();

src/babel/patch.js

@@ -1,7 +1,7 @@
 import estraverse from "estraverse";
 import extend from "lodash/object/extend";
 import types from "ast-types";
-import t from "./types";
+import * as t from "./types";
 
 // estraverse
 
@@ -9,8 +9,8 @@ extend(estraverse.VisitorKeys, t.VISITOR_KEYS);
 
 // regenerator-babel/ast-types
 
-var def   = types.Type.def;
-var or    = types.Type.or;
+var def = types.Type.def;
+var or  = types.Type.or;
 
 def("File")
   .bases("Node")

src/babel/tools/build-external-helpers.js

@@ -1,8 +1,9 @@
-import buildHelpers from "./build-helpers";
-import generator from "./generation";
-import * as messages from "./messages";
-import * as util from  "./util";
-import t from "./types";
+import generator from "../generation";
+import * as messages from "../messages";
+import * as util from  "../util";
+import File from "../transformation/file";
+import each from "lodash/collection/each";
+import * as t from "../types";
 
 function buildGlobal(namespace, builder) {
   var body      = [];
@@ -49,8 +50,20 @@ function buildVar(namespace, builder) {
   return t.program(body);
 }
 
+function buildHelpers(body, namespace, whitelist = []) {
+  each(File.helpers, function (name) {
+    if (whitelist.length && whitelist.indexOf(name) === -1) return;
+
+    var key = t.identifier(t.toIdentifier(name));
+    body.push(t.expressionStatement(
+      t.assignmentExpression("=", t.memberExpression(namespace, key), util.template(name))
+    ));
+  });
+}
+
 export default function (whitelist, outputType = "global") {
   var namespace = t.identifier("babelHelpers");
+
   var builder = function (body) {
     return buildHelpers(body, namespace, whitelist);
   };

src/babel/transformation/file.js

@@ -7,13 +7,14 @@ import generate from "../generation";
 import defaults from "lodash/object/defaults";
 import includes from "lodash/collection/includes";
 import assign from "lodash/object/assign";
+import Logger from "./logger";
 import parse from "../helpers/parse";
 import Scope from "../traversal/scope";
 import slash from "slash";
 import * as util from  "../util";
 import path from "path";
 import each from "lodash/collection/each";
-import t from "../types";
+import * as t from "../types";
 
 var checkTransformerVisitor = {
   enter(node, parent, scope, state) {
@@ -23,7 +24,7 @@ var checkTransformerVisitor = {
 
 function checkNode(stack, node, scope) {
   each(stack, function (pass) {
-    if (pass.shouldRun) return;
+    if (pass.shouldRun || pass.ran) return;
     pass.checkNode(node, scope);
   });
 }
@@ -41,6 +42,7 @@ export default class File {
 
     this.lastStatements = [];
     this.opts           = this.normalizeOptions(opts);
+    this.log            = new Logger(this);
     this.ast            = {};
 
     this.buildTransformers();
@@ -50,6 +52,7 @@ export default class File {
     "inherits",
     "defaults",
     "create-class",
+    "create-computed-class",
     "apply-constructor",
     "tagged-template-literal",
     "tagged-template-literal-loose",
@@ -121,7 +124,7 @@ export default class File {
     "accept"
   ];
 
-  normalizeOptions(opts) {
+  normalizeOptions(opts: Object) {
     opts = assign({}, opts);
 
     for (var key in opts) {
@@ -136,7 +139,7 @@ export default class File {
       returnUsedHelpers:      false,
       externalHelpers:        false,
       auxilaryComment:        "",
-      inputSourceMap:         false,
+      inputSourceMap:         null,
       experimental:           false,
       reactCompat:            false,
       playground:             false,
@@ -227,7 +230,7 @@ export default class File {
     return opts;
   };
 
-  isLoose(key) {
+  isLoose(key: string) {
     return includes(this.opts.loose, key);
   }
 
@@ -259,13 +262,7 @@ export default class File {
     this.transformers = transformers;
   }
 
-  debug(msg) {
-    var parts = this.opts.filename;
-    if (msg) parts += `: ${msg}`;
-    util.debug(parts);
-  }
-
-  getModuleFormatter(type) {
+  getModuleFormatter(type: string) {
     var ModuleFormatter = isFunction(type) ? type : transform.moduleFormatters[type];
 
     if (!ModuleFormatter) {
@@ -280,19 +277,21 @@ export default class File {
     return new ModuleFormatter(this);
   }
 
-  parseInputSourceMap(code) {
+  parseInputSourceMap(code: string) {
     var opts = this.opts;
 
-    var inputMap = convertSourceMap.fromSource(code);
-    if (inputMap) {
-      opts.inputSourceMap = inputMap.toObject();
-      code = convertSourceMap.removeComments(code);
+    if (opts.inputSourceMap !== false) {
+      var inputMap = convertSourceMap.fromSource(code);
+      if (inputMap) {
+        opts.inputSourceMap = inputMap.toObject();
+        code = convertSourceMap.removeComments(code);
+      }
     }
 
     return code;
   }
 
-  parseShebang(code) {
+  parseShebang(code: string) {
     var shebangMatch = shebangRegex.exec(code);
 
     if (shebangMatch) {
@@ -305,15 +304,15 @@ export default class File {
     return code;
   }
 
-  set(key, val) {
+  set(key: string, val): any {
     return this.data[key] = val;
   };
 
-  setDynamic(key, fn) {
+  setDynamic(key: string, fn: Function) {
     this.dynamicData[key] = fn;
   }
 
-  get(key) {
+  get(key: string): any {
     var data = this.data[key];
     if (data) {
       return data;
@@ -325,7 +324,7 @@ export default class File {
     }
   }
 
-  addImport(source, name, noDefault) {
+  addImport(source: string, name?: string, noDefault?: boolean): Object {
     name ||= source;
     var id = this.dynamicImportIds[name];
 
@@ -349,11 +348,11 @@ export default class File {
     return id;
   }
 
-  isConsequenceExpressionStatement(node) {
+  isConsequenceExpressionStatement(node: Object): boolean {
     return t.isExpressionStatement(node) && this.lastStatements.indexOf(node) >= 0;
   }
 
-  attachAuxiliaryComment(node) {
+  attachAuxiliaryComment(node: Object): Object {
     var comment = this.opts.auxiliaryComment;
     if (comment) {
       node.leadingComments ||= [];
@@ -365,7 +364,7 @@ export default class File {
     return node;
   }
 
-  addHelper(name) {
+  addHelper(name: string): Object {
     if (!includes(File.helpers, name)) {
       throw new ReferenceError(`Unknown helper ${name}`);
     }
@@ -377,10 +376,13 @@ export default class File {
 
     this.usedHelpers[name] = true;
 
+    var generator = this.get("helperGenerator");
     var runtime = this.get("helpersNamespace");
-    if (runtime) {
-      name = t.identifier(t.toIdentifier(name));
-      return t.memberExpression(runtime, name);
+    if (generator) {
+      return generator(name);
+    } else if (runtime) {
+      var id = t.identifier(t.toIdentifier(name));
+      return t.memberExpression(runtime, id);
     } else {
       var ref = util.template(name);
       ref._compact = true;
@@ -394,10 +396,6 @@ export default class File {
     }
   }
 
-  logDeopt() {
-    // todo, (node, msg)
-  }
-
   errorWithNode(node, msg, Error = SyntaxError) {
     var loc = node.loc.start;
     var err = new Error(`Line ${loc.line}: ${msg}`);
@@ -405,14 +403,14 @@ export default class File {
     return err;
   }
 
-  addCode(code) {
+  addCode(code: string) {
     code = (code || "") + "";
     code = this.parseInputSourceMap(code);
     this.code = code;
     return this.parseShebang(code);
   }
 
-  parse(code) {
+  parse(code: string) {
     code = this.addCode(code);
 
     var opts = this.opts;
@@ -427,7 +425,7 @@ export default class File {
   }
 
   transform(ast) {
-    this.debug();
+    this.log.debug();
 
     this.ast = ast;
     this.lastStatements = t.getLastStatements(ast.program);
@@ -449,7 +447,7 @@ export default class File {
     this.call("post");
   }
 
-  call(key) {
+  call(key: string) {
     var stack = this.transformerStack;
     for (var i = 0; i < stack.length; i++) {
       var transformer = stack[i].transformer;
@@ -477,7 +475,7 @@ export default class File {
     });
   }
 
-  mergeSourceMap(map) {
+  mergeSourceMap(map: Object) {
     var opts = this.opts;
 
     var inputMap = opts.inputSourceMap;
@@ -499,7 +497,11 @@ export default class File {
     return map;
   }
 
-  generate() {
+  generate(): {
+    code: string;
+    map?: Object;
+    ast?: Object;
+  } {
     var opts = this.opts;
     var ast  = this.ast;
 
@@ -531,7 +533,7 @@ export default class File {
       result.code += "\n" + convertSourceMap.fromObject(result.map).toComment();
     }
 
-    if (opts.sourceMap === "both") {
+    if (opts.sourceMap === "inline") {
       result.map = null;
     }
 

src/babel/transformation/helpers/build-binary-assignment-operator-transformer.js

@@ -1,5 +1,5 @@
 import explode from "./explode-assignable-expression";
-import t from "../../types";
+import * as t from "../../types";
 
 export default function (exports, opts) {
   var isAssignment = function (node) {

src/babel/transformation/helpers/build-comprehension.js

@@ -1,4 +1,4 @@
-import t from "../../types";
+import * as t from "../../types";
 
 export default function build(node, buildBody) {
   var self = node.blocks.shift();

src/babel/transformation/helpers/build-conditional-assignment-operator-transformer.js

@@ -1,5 +1,5 @@
 import explode from "./explode-assignable-expression";
-import t from "../../types";
+import * as t from "../../types";
 
 export default function (exports, opts) {
   var buildAssignment = function (left, right) {

src/babel/transformation/helpers/build-react-transformer.js

@@ -7,7 +7,7 @@ import isString from "lodash/lang/isString";
 import * as messages from "../../messages";
 import esutils from "esutils";
 import * as react from "./react";
-import t from "../../types";
+import * as t from "../../types";
 
 export default function (exports, opts) {
   exports.check = function (node) {

src/babel/transformation/helpers/define-map.js

@@ -2,36 +2,43 @@ import cloneDeep from "lodash/lang/cloneDeep";
 import traverse from "../../traversal";
 import each from "lodash/collection/each";
 import has from "lodash/object/has";
-import t from "../../types";
+import * as t from "../../types";
 
 export function push(mutatorMap, key, kind, computed, value) {
-  var alias;
+  var alias = t.toKeyAlias({ computed }, key);
 
-  if (t.isIdentifier(key)) {
-    alias = key.name;
-    if (computed) alias = `computed:${alias}`;
-  } else if (t.isLiteral(key)) {
-    alias = String(key.value);
-  } else {
-    alias = JSON.stringify(traverse.removeProperties(t.cloneDeep(key)));
-  }
-
-  var map;
-  if (has(mutatorMap, alias)) {
-    map = mutatorMap[alias];
-  } else {
-    map = {};
-  }
+  var map = {};
+  if (has(mutatorMap, alias)) map = mutatorMap[alias];
   mutatorMap[alias] = map;
 
   map._key = key;
-  if (computed) {
-    map._computed = true;
-  }
+  if (computed) map._computed = true;
 
   map[kind] = value;
 }
 
+export function hasComputed(mutatorMap) {
+  for (var key in mutatorMap) {
+    if (mutatorMap[key]._computed) {
+      return true;
+    }
+  }
+  return false;
+}
+
+export function toComputedObjectFromClass(obj) {
+  var objExpr = t.arrayExpression([]);
+
+  for (var i = 0; i < obj.properties.length; i++) {
+    var prop = obj.properties[i];
+    var val = prop.value;
+    val.properties.unshift(t.property("init", t.identifier("key"), t.toComputedKey(prop)));
+    objExpr.elements.push(val);
+  }
+
+  return objExpr;
+}
+
 export function toClassObject(mutatorMap) {
   var objExpr = t.objectExpression([]);
 
@@ -49,6 +56,7 @@ export function toClassObject(mutatorMap) {
       var prop = t.property("init", t.identifier(key), node);
       t.inheritsComments(prop, inheritNode);
       t.removeComments(inheritNode);
+
       mapNode.properties.push(prop);
     });
 
@@ -59,35 +67,11 @@ export function toClassObject(mutatorMap) {
 }
 
 export function toDefineObject(mutatorMap) {
-  var objExpr = t.objectExpression([]);
-
   each(mutatorMap, function (map) {
-    var mapNode = t.objectExpression([]);
-
-    var propNode = t.property("init", map._key, mapNode, map._computed);
-
-    if (map.value) {
-      map.writable = t.literal(true);
-    }
-
+    if (map.value) map.writable = t.literal(true);
     map.configurable = t.literal(true);
     map.enumerable = t.literal(true);
-
-    each(map, function (node, key) {
-      if (key[0] === "_") return;
-
-      node = t.clone(node);
-      var inheritNode = node;
-      if (t.isMethodDefinition(node)) node = node.value;
-
-      var prop = t.property("init", t.identifier(key), node);
-      t.inheritsComments(prop, inheritNode);
-      t.removeComments(inheritNode);
-      mapNode.properties.push(prop);
-    });
-
-    objExpr.properties.push(propNode);
   });
 
-  return objExpr;
+  return toClassObject(mutatorMap);
 }

src/babel/transformation/helpers/explode-assignable-expression.js

@@ -1,4 +1,4 @@
-import t from "../../types";
+import * as t from "../../types";
 
 var getObjRef = function (node, nodes, file, scope) {
   var ref;

src/babel/transformation/helpers/get-function-arity.js

@@ -1,4 +1,4 @@
-import t from "../../types";
+import * as t from "../../types";
 
 export default function (node) {
   var lastNonDefault = 0;

src/babel/transformation/helpers/name-method.js

@@ -1,6 +1,6 @@
 import getFunctionArity from "./get-function-arity";
 import * as util from  "../../util";
-import t from "../../types";
+import * as t from "../../types";
 
 var visitor = {
   enter(node, parent, scope, state) {
@@ -111,7 +111,7 @@ export function bare(node, parent, scope) {
   if (node.id) return node;
 
   var id;
-  if (t.isProperty(parent) && parent.kind === "init" && !parent.computed) {
+  if (t.isProperty(parent) && parent.kind === "init" && (!parent.computed || t.isLiteral(parent.key))) {
     // { foo() {} };
     id = parent.key;
   } else if (t.isVariableDeclarator(parent)) {
@@ -121,9 +121,16 @@ export function bare(node, parent, scope) {
     return node;
   }
 
-  if (!t.isIdentifier(id)) return node;
+  var name;
+  if (t.isLiteral(id)) {
+    name = id.value;
+  } else if (t.isIdentifier(id)) {
+    name = id.name;
+  } else {
+    return;
+  }
 
-  var name = t.toIdentifier(id.name);
+  name = t.toIdentifier(name);
   id = t.identifier(name);
 
   var state = visit(node, name, scope);

src/babel/transformation/helpers/react.js

@@ -1,4 +1,4 @@
-import t from "../../types";
+import * as t from "../../types";
 
 var isCreateClassCallExpression = t.buildMatchMemberExpression("React.createClass");
 

src/babel/transformation/helpers/regex.js

@@ -1,5 +1,5 @@
 import pull from "lodash/array/pull";
-import t from "../../types";
+import * as t from "../../types";
 
 export function is(node, flag) {
   return t.isLiteral(node) && node.regex && node.regex.flags.indexOf(flag) >= 0;
@@ -7,7 +7,7 @@ export function is(node, flag) {
 
 export function pullFlag(node, flag) {
   var flags = node.regex.flags.split("");
-  if (node.regex.flags.indexOf("u") < 0) return;
-  pull(flags, "u");
+  if (node.regex.flags.indexOf(flag) < 0) return;
+  pull(flags, flag);
   node.regex.flags = flags.join("");
 }

src/babel/transformation/helpers/remap-async-to-generator.js

@@ -1,7 +1,7 @@
-import t from "../../types";
+import * as t from "../../types";
 
-var visitor = {
-  enter(node) {
+var awaitVisitor = {
+  enter(node, parent, scope, state) {
     if (t.isFunction(node)) this.skip();
 
     if (t.isAwaitExpression(node)) {
@@ -16,13 +16,23 @@ var visitor = {
   }
 };
 
+var referenceVisitor = {
+  enter(node, parent, scope, state) {
+    var name = state.id.name;
+    if (t.isReferencedIdentifier(node, parent, { name: name }) && scope.bindingIdentifierEquals(name, state.id)) {
+      return state.ref ||= scope.generateUidIdentifier(name);
+    }
+  }
+};
+
 export default function (node, callId, scope) {
   node.async = false;
   node.generator = true;
 
-  scope.traverse(node, visitor);
+  scope.traverse(node, awaitVisitor, state);
 
   var call = t.callExpression(callId, [node]);
+
   var id = node.id;
   node.id = null;
 
@@ -33,6 +43,16 @@ export default function (node, callId, scope) {
     declar._blockHoist = true;
     return declar;
   } else {
+    if (id) {
+      var state = { id: id };
+      scope.traverse(node, referenceVisitor, state);
+
+      if (state.ref) {
+        scope.parent.push({ id: state.ref });
+        return t.assignmentExpression("=", state.ref, call);
+      }
+    }
+
     return call;
   }
 };

src/babel/transformation/helpers/replace-supers.js

@@ -1,7 +1,7 @@
 module.exports = ReplaceSupers;
 
 import * as messages from "../../messages";
-import t from "../../types";
+import * as t from "../../types";
 
 
 function isIllegalBareSuper(node, parent) {
@@ -47,12 +47,9 @@ export default class ReplaceSupers {
 
   /**
    * Description
-   *
-   * @param {Object} opts
-   * @param {Boolean} [inClass]
    */
 
-  constructor(opts, inClass) {
+  constructor(opts: Object, inClass?: boolean = false) {
     this.topLevelThisReference = opts.topLevelThisReference;
     this.methodNode            = opts.methodNode;
     this.superRef              = opts.superRef;
@@ -76,15 +73,9 @@ export default class ReplaceSupers {
    *
    *   _set(Object.getPrototypeOf(CLASS.prototype), "METHOD", "VALUE", this)
    *
-   * @param {Node} property
-   * @param {Node} value
-   * @param {Boolean} isComputed
-   * @param {Node} thisExpression
-   *
-   * @returns {Node}
    */
 
-  setSuperProperty(property, value, isComputed, thisExpression) {
+  setSuperProperty(property: Object, value: Object, isComputed: boolean, thisExpression: Object): Object {
     return t.callExpression(
       this.file.addHelper("set"),
       [
@@ -108,14 +99,9 @@ export default class ReplaceSupers {
    *
    *   _get(Object.getPrototypeOf(CLASS.prototype), "METHOD", this)
    *
-   * @param {Node} property
-   * @param {Boolean} isComputed
-   * @param {Node} thisExpression
-   *
-   * @returns {Node}
    */
 
-  getSuperProperty(property, isComputed, thisExpression) {
+  getSuperProperty(property: Object, isComputed: boolean, thisExpression: Object): Object {
     return t.callExpression(
       this.file.addHelper("get"),
       [
@@ -141,12 +127,9 @@ export default class ReplaceSupers {
 
   /**
    * Description
-   *
-   * @param {Object} node
-   * @param {Boolean} topLevel
    */
 
-  traverseLevel(node, topLevel) {
+  traverseLevel(node: Object, topLevel: boolean) {
     var state = { self: this, topLevel: topLevel };
     this.scope.traverse(node, visitor, state);
   }
@@ -169,14 +152,9 @@ export default class ReplaceSupers {
 
   /**
    * Description
-   *
-   * @param {Object} node
-   * @param {Object} id
-   * @param {Object} parent
-   * @returns {Object}
    */
 
-  getLooseSuperProperty(id, parent) {
+  getLooseSuperProperty(id: Object, parent: Object) {
     var methodNode = this.methodNode;
     var methodName = methodNode.key;
     var superRef   = this.superRef || t.identifier("Function");
@@ -211,13 +189,9 @@ export default class ReplaceSupers {
 
   /**
    * Description
-   *
-   * @param {Function} getThisReference
-   * @param {Object} node
-   * @param {Object} parent
    */
 
-  looseHandle(getThisReference, node, parent) {
+  looseHandle(getThisReference: Function, node: Object, parent: Object) {
     if (t.isIdentifier(node, { name: "super" })) {
       this.hasSuper = true;
       return this.getLooseSuperProperty(node, parent);
@@ -235,13 +209,9 @@ export default class ReplaceSupers {
 
   /**
    * Description
-   *
-   * @param {Function} getThisReference
-   * @param {Object} node
-   * @param {Object} parent
    */
 
-  specHandle(getThisReference, node, parent) {
+  specHandle(getThisReference: Function, node: Object, parent: Object) {
     var methodNode = this.methodNode;
     var property;
     var computed;

src/babel/transformation/helpers/strict.js

@@ -1,4 +1,4 @@
-import t from "../../types";
+import * as t from "../../types";
 
 export function has(node) {
   var first = node.body[0];

src/babel/transformation/index.js

@@ -4,7 +4,7 @@ import object from "../helpers/object";
 import File from "./file";
 import each from "lodash/collection/each";
 
-export default function transform(code, opts) {
+export default function transform(code: code, opts?: Object) {
   var file = new File(opts);
   return file.parse(code);
 }
@@ -18,7 +18,7 @@ transform.fromAst = function (ast, code, opts) {
   return file.generate();
 };
 
-transform._ensureTransformerNames = function (type, rawKeys) {
+transform._ensureTransformerNames = function (type: string, rawKeys: Array<string>) {
   var keys = [];
 
   for (var i = 0; i < rawKeys.length; i++) {

src/babel/transformation/logger.js

@@ -0,0 +1,22 @@
+import * as util from  "../util";
+
+export default class Logger {
+  constructor(file: File) {
+    this.filename = file.opts.filename;
+    this.file     = file;
+  }
+
+  _buildMessage(msg: string): string {
+    var parts = this.filename;
+    if (msg) parts += `: ${msg}`;
+    return parts;
+  }
+
+  debug(msg: string) {
+    util.debug(this._buildMessage(msg));
+  }
+
+  deopt(node: Object, msg: string) {
+    util.debug(this._buildMessage(msg));
+  }
+}

src/babel/transformation/modules/_default.js

@@ -2,7 +2,7 @@ import * as messages from "../../messages";
 import extend from "lodash/object/extend";
 import object from "../../helpers/object";
 import * as util from  "../../util";
-import t from "../../types";
+import * as t from "../../types";
 
 var remapVisitor = {
   enter(node, parent, scope, formatter) {

src/babel/transformation/modules/amd.js

@@ -3,7 +3,7 @@ import CommonFormatter from "./common";
 import includes from "lodash/collection/includes";
 import values from "lodash/object/values";
 import * as util from  "../../util";
-import t from "../../types";
+import * as t from "../../types";
 
 export default class AMDFormatter extends DefaultFormatter {
   init = CommonFormatter.prototype.init;

src/babel/transformation/modules/common.js

@@ -1,7 +1,7 @@
 import DefaultFormatter from "./_default";
 import includes from "lodash/collection/includes";
 import * as util from  "../../util";
-import t from "../../types";
+import * as t from "../../types";
 
 export default class CommonJSFormatter extends DefaultFormatter {
   init() {
@@ -13,7 +13,7 @@ export default class CommonJSFormatter extends DefaultFormatter {
     if (!this.noInteropRequireImport && this.hasNonDefaultExports) {
       var templateName = "exports-module-declaration";
       if (this.file.isLoose("es6.modules")) templateName += "-loose";
-      file.ast.program.body.push(util.template(templateName, true));
+      file.ast.program.body.unshift(util.template(templateName, true));
     }
   };
 

src/babel/transformation/modules/ignore.js

@@ -1,4 +1,4 @@
-import t from "../../types";
+import * as t from "../../types";
 
 export default class IgnoreFormatter {
   exportDeclaration(node, nodes) {

src/babel/transformation/modules/system.js

@@ -4,7 +4,7 @@ import * as util from  "../../util";
 import last from "lodash/array/last";
 import each from "lodash/collection/each";
 import map from "lodash/collection/map";
-import t from "../../types";
+import * as t from "../../types";
 
 var hoistVariablesVisitor = {
   enter(node, parent, scope, hoistDeclarators) {

src/babel/transformation/modules/umd.js

@@ -1,7 +1,7 @@
 import AMDFormatter from "./amd";
 import values from "lodash/object/values";
 import * as util from  "../../util";
-import t from "../../types";
+import * as t from "../../types";
 
 export default class UMDFormatter extends AMDFormatter {
   transform(program) {

src/babel/transformation/templates/create-computed-class.js

@@ -0,0 +1,16 @@
+(function() {
+  function defineProperties(target, props) {
+    for (var i = 0; i < props.length; i ++) {
+      var prop = props[i];
+      prop.configurable = true;
+      if (prop.value) prop.writable = true;
+      Object.defineProperty(target, prop.key, prop);
+    }
+  }
+
+  return function (Constructor, protoProps, staticProps) {
+    if (protoProps) defineProperties(Constructor.prototype, protoProps);
+    if (staticProps) defineProperties(Constructor, staticProps);
+    return Constructor;
+  };
+})()

src/babel/transformation/templates/self-contained-helpers-head.js

@@ -1,2 +1,2 @@
-var helpers = exports.default = {};
+exports.default = HELPER;
 exports.__esModule = true;

src/babel/transformation/transformer-pass.js

@@ -6,14 +6,15 @@ import includes from "lodash/collection/includes";
  */
 
 export default class TransformerPass {
-  constructor(file, transformer) {
+  constructor(file: File, transformer: Transformer) {
     this.transformer = transformer;
     this.shouldRun   = !transformer.check;
     this.handlers    = transformer.handlers;
     this.file        = file;
+    this.ran         = false;
   }
 
-  canRun() {
+  canRun(): boolean {
     var transformer = this.transformer;
 
     var opts = this.file.opts;
@@ -42,7 +43,7 @@ export default class TransformerPass {
     return true;
   }
 
-  checkNode(node) {
+  checkNode(node: Object): boolean {
     var check = this.transformer.check;
     if (check) {
       return this.shouldRun = check(node);
@@ -56,8 +57,10 @@ export default class TransformerPass {
 
     var file = this.file;
 
-    file.debug(`Running transformer ${this.transformer.key}`);
+    file.log.debug(`Running transformer ${this.transformer.key}`);
 
     file.scope.traverse(file.ast, this.handlers, file);
+
+    this.ran = true;
   }
 }

src/babel/transformation/transformer.js

@@ -12,7 +12,7 @@ import each from "lodash/collection/each";
  */
 
 export default class Transformer {
-  constructor(transformerKey, transformer, opts) {
+  constructor(transformerKey: key, transformer: Object, opts: Object) {
     transformer = assign({}, transformer);
 
     var take = function (key) {
@@ -36,7 +36,7 @@ export default class Transformer {
     this.key      = transformerKey;
   }
 
-  normalize(transformer) {
+  normalize(transformer: Object): Object {
     if (isFunction(transformer)) {
       transformer = { ast: transformer };
     }
@@ -65,7 +65,7 @@ export default class Transformer {
     return transformer;
   }
 
-  buildPass(file) {
+  buildPass(file: File): TransformerPass {
     return new TransformerPass(file, this);
   }
 }

src/babel/transformation/transformers/deprecated.json

@@ -1,6 +1,7 @@
 {
   "selfContained": "runtime",
   "unicode-regex": "regex.unicode",
+  "spec.typeofSymbol": "es6.symbols",
 
   "minification.deadCodeElimination": "utility.deadCodeElimination",
   "minification.removeConsoleCalls": "utility.removeConsole",

src/babel/transformation/transformers/es3/member-expression-literals.js

@@ -1,4 +1,4 @@
-import t from "../../../types";
+import * as t from "../../../types";
 
 export function MemberExpression(node) {
   var prop = node.property;

src/babel/transformation/transformers/es3/property-literals.js

@@ -1,4 +1,4 @@
-import t from "../../../types";
+import * as t from "../../../types";
 
 export function Property(node) {
   var key = node.key;

src/babel/transformation/transformers/es5/properties.mutators.js

@@ -1,5 +1,5 @@
 import * as defineMap from "../../helpers/define-map";
-import t from "../../../types";
+import * as t from "../../../types";
 
 export function check(node) {
   return t.isProperty(node) && (node.kind === "get" || node.kind === "set");

src/babel/transformation/transformers/es6/arrow-functions.js

@@ -1,4 +1,4 @@
-import t from "../../../types";
+import * as t from "../../../types";
 
 export var check = t.isArrowFunctionExpression;
 

src/babel/transformation/transformers/es6/block-scoping-tdz.js

@@ -1,4 +1,4 @@
-import t from "../../../types";
+import * as t from "../../../types";
 
 var visitor = {
   enter(node, parent, scope, state) {

src/babel/transformation/transformers/es6/block-scoping.js

@@ -1,7 +1,7 @@
 import traverse from "../../../traversal";
 import object from "../../../helpers/object";
 import * as util from  "../../../util";
-import t from "../../../types";
+import * as t from "../../../types";
 import values from "lodash/object/values";
 import extend from "lodash/object/extend";
 
@@ -69,13 +69,14 @@ export function Loop(node, parent, scope, file) {
     t.ensureBlock(node);
     node.body._letDeclarators = [init];
   }
-  var blockScoping = new BlockScoping(node, node.body, parent, scope, file);
-  blockScoping.run();
+
+  var blockScoping = new BlockScoping(this, node.body, parent, scope, file);
+  return blockScoping.run();
 }
 
 export function BlockStatement(block, parent, scope, file) {
   if (!t.isLoop(parent)) {
-    var blockScoping = new BlockScoping(false, block, parent, scope, file);
+    var blockScoping = new BlockScoping(null, block, parent, scope, file);
     blockScoping.run();
   }
 }
@@ -222,25 +223,24 @@ class BlockScoping {
 
   /**
    * Description
-   *
-   * @param {Boolean|Node} loopParent
-   * @param {Node} block
-   * @param {Node} parent
-   * @param {Scope} scope
-   * @param {File} file
    */
 
-  constructor(loopParent, block, parent, scope, file) {
-    this.loopParent = loopParent;
-    this.parent     = parent;
-    this.scope      = scope;
-    this.block      = block;
-    this.file       = file;
+  constructor(loopPath?: TraversalPath, block: Object, parent: Object, scope: Scope, file: File) {
+    this.parent = parent;
+    this.scope  = scope;
+    this.block  = block;
+    this.file   = file;
 
     this.outsideLetReferences = object();
     this.hasLetReferences     = false;
     this.letReferences        = block._letReferences = object();
     this.body                 = [];
+
+    if (loopPath) {
+      this.loopParent = loopPath.parent;
+      this.loopLabel  = t.isLabeledStatement(this.loopParent) && this.loopParent.label;
+      this.loop       = loopPath.node;
+    }
   }
 
   /**
@@ -265,6 +265,10 @@ class BlockScoping {
     } else {
       this.remap();
     }
+
+    if (this.loopLabel && !t.isLabeledStatement(this.loopParent)) {
+      return t.labeledStatement(this.loopLabel, this.loop);
+    }
   }
 
   /**
@@ -303,11 +307,11 @@ class BlockScoping {
 
     //
 
-    var loopParent = this.loopParent;
-    if (loopParent) {
-      traverseReplace(loopParent.right, loopParent, scope, remaps);
-      traverseReplace(loopParent.test, loopParent, scope, remaps);
-      traverseReplace(loopParent.update, loopParent, scope, remaps);
+    var loop = this.loop;
+    if (loop) {
+      traverseReplace(loop.right, loop, scope, remaps);
+      traverseReplace(loop.test, loop, scope, remaps);
+      traverseReplace(loop.update, loop, scope, remaps);
     }
 
     scope.traverse(this.block, replaceVisitor, remaps);
@@ -323,7 +327,7 @@ class BlockScoping {
     var outsideRefs = this.outsideLetReferences;
 
     // remap loop heads with colliding variables
-    if (this.loopParent) {
+    if (this.loop) {
       for (var name in outsideRefs) {
         var id = outsideRefs[name];
 
@@ -444,7 +448,7 @@ class BlockScoping {
       ignoreLabeless:   false,
       innerLabels:      [],
       hasReturn:        false,
-      isLoop:           !!this.loopParent,
+      isLoop:           !!this.loop,
       map:              {}
     };
 
@@ -466,12 +470,9 @@ class BlockScoping {
   /**
    * Turn a `VariableDeclaration` into an array of `AssignmentExpressions` with
    * their declarations hoisted to before the closure wrapper.
-   *
-   * @param {Node} node VariableDeclaration
-   * @returns {Array}
    */
 
-  pushDeclar(node) {
+  pushDeclar(node: { type: "VariableDeclaration" }): Array<Object> {
     this.body.push(t.variableDeclaration(node.kind, node.declarations.map(function (declar) {
       return t.variableDeclarator(declar.id);
     })));
@@ -491,12 +492,9 @@ class BlockScoping {
 
   /**
    * Push the closure to the body.
-   *
-   * @param {Node} ret Identifier
-   * @param {Node} call CallExpression
    */
 
-  build(ret, call) {
+  build(ret: { type: "Identifier" }, call: { type: "CallExpression" }) {
     var has = this.has;
     if (has.hasReturn || has.hasBreakContinue) {
       this.buildHas(ret, call);
@@ -507,19 +505,16 @@ class BlockScoping {
 
   /**
    * Description
-   *
-   * @param {Node} ret Identifier
-   * @param {Node} call CallExpression
    */
 
-  buildHas(ret, call) {
+  buildHas(ret: { type: "Identifier" }, call: { type: "CallExpression" }) {
     var body = this.body;
 
     body.push(t.variableDeclaration("var", [
       t.variableDeclarator(ret, call)
     ]));
 
-    var loopParent = this.loopParent;
+    var loop = this.loop;
     var retCheck;
     var has = this.has;
     var cases = [];
@@ -532,11 +527,6 @@ class BlockScoping {
     }
 
     if (has.hasBreakContinue) {
-      if (!loopParent) {
-        throw new Error("Has no loop parent but we're trying to reassign breaks " +
-                        "and continues, something is going wrong here.");
-      }
-
       for (var key in has.map) {
         cases.push(t.switchCase(t.literal(key), [has.map[key]]));
       }
@@ -552,6 +542,14 @@ class BlockScoping {
           single.consequent[0]
         )));
       } else {
+        // #998
+        for (var i = 0; i < cases.length; i++) {
+          var caseConsequent = cases[i].consequent[0];
+          if (t.isBreakStatement(caseConsequent) && !caseConsequent.label) {
+            caseConsequent.label = this.loopLabel ||= this.file.scope.generateUidIdentifier("loop");
+          }
+        }
+
         body.push(this.file.attachAuxiliaryComment(t.switchStatement(ret, cases)));
       }
     } else {

src/babel/transformation/transformers/es6/classes.js

@@ -4,7 +4,7 @@ import * as defineMap from "../../helpers/define-map";
 import * as messages from "../../../messages";
 import * as util from  "../../../util";
 import traverse from "../../../traversal";
-import t from "../../../types";
+import * as t from "../../../types";
 
 export var check = t.isClass;
 
@@ -56,14 +56,9 @@ class ClassTransformer {
 
   /**
    * Description
-   *
-   * @param {Node} node
-   * @param {Node} parent
-   * @param {Scope} scope
-   * @param {File} file
    */
 
-  constructor(node, parent, scope, file) {
+  constructor(node: Object, parent: Object, scope: Scope, file: File) {
     this.parent = parent;
     this.scope  = scope;
     this.node   = node;
@@ -222,6 +217,7 @@ class ClassTransformer {
 
     var instanceProps;
     var staticProps;
+    var classHelper = "create-class";
 
     if (this.hasInstanceMutators) {
       instanceProps = defineMap.toClassObject(this.instanceMutatorMap);
@@ -232,24 +228,28 @@ class ClassTransformer {
     }
 
     if (instanceProps || staticProps) {
+      if (defineMap.hasComputed(this.instanceMutatorMap) || defineMap.hasComputed(this.staticMutatorMap)) {
+        if (instanceProps) instanceProps = defineMap.toComputedObjectFromClass(instanceProps);
+        if (staticProps) staticProps = defineMap.toComputedObjectFromClass(staticProps);
+        classHelper = "create-computed-class";
+      }
+
       instanceProps ||= t.literal(null);
 
       var args = [this.classRef, instanceProps];
       if (staticProps) args.push(staticProps);
 
       body.push(t.expressionStatement(
-        t.callExpression(this.file.addHelper("create-class"), args)
+        t.callExpression(this.file.addHelper(classHelper), args)
       ));
     }
   }
 
   /**
    * Description
-   *
-   * @param {Node} node
    */
 
-   verifyConstructor(node) {
+   verifyConstructor(node: Object) {
     return; // enable this for the next major
 
     var state = {
@@ -267,11 +267,9 @@ class ClassTransformer {
 
   /**
    * Push a method to its respective mutatorMap.
-   *
-   * @param {Node} node MethodDefinition
    */
 
-  pushMethod(node) {
+  pushMethod(node: { type: "MethodDefinition" }) {
     var methodName = node.key;
 
     var kind = node.kind;
@@ -308,11 +306,9 @@ class ClassTransformer {
 
   /**
    * Description
-   *
-   * @param {Node} node
    */
 
-  pushProperty(node) {
+  pushProperty(node: Object) {
     if (!node.value) return;
 
     var key;
@@ -332,11 +328,9 @@ class ClassTransformer {
 
   /**
    * Replace the constructor body of our class.
-   *
-   * @param {Node} method MethodDefinition
    */
 
-  pushConstructor(method) {
+  pushConstructor(method: { type: "MethodDefinition" }) {
     if (method.kind) {
       throw this.file.errorWithNode(method, messages.get("classesIllegalConstructorKind"));
     }

src/babel/transformation/transformers/es6/constants.js

@@ -1,5 +1,5 @@
 import * as messages from "../../../messages";
-import t from "../../../types";
+import * as t from "../../../types";
 
 export function check(node) {
   return t.isVariableDeclaration(node, { kind: "const" });

src/babel/transformation/transformers/es6/destructuring.js

@@ -1,5 +1,5 @@
 import * as messages from "../../../messages";
-import t from "../../../types";
+import * as t from "../../../types";
 
 export var check = t.isPattern;
 
@@ -135,10 +135,7 @@ export function AssignmentExpression(node, parent, scope, file) {
   if (!t.isPattern(node.left)) return;
 
   var ref = scope.generateUidIdentifier("temp");
-  scope.push({
-    key: ref.name,
-    id: ref
-  });
+  scope.push({ id: ref });
 
   var nodes = [];
   nodes.push(t.assignmentExpression("=", ref, node.right));
@@ -293,14 +290,21 @@ class DestructuringTransformer {
 
     //
 
-    this.nodes.push(this.buildVariableAssignment(
-      pattern.left,
-      t.conditionalExpression(
-        t.binaryExpression("===", tempValueRef, t.identifier("undefined")),
-        pattern.right,
-        tempValueRef
-      )
-    ));
+    var tempConditional = t.conditionalExpression(
+      t.binaryExpression("===", tempValueRef, t.identifier("undefined")),
+      pattern.right,
+      tempValueRef
+    );
+
+    var left = pattern.left;
+    if (t.isPattern(left)) {
+      this.nodes.push(t.expressionStatement(
+        t.assignmentExpression("=", tempValueRef, tempConditional)
+      ));
+      this.push(left, tempValueRef);
+    } else {
+      this.nodes.push(this.buildVariableAssignment(left, tempConditional));
+    }
   }
 
   pushObjectSpread(pattern, objRef, spreadProp, spreadPropIndex) {

src/babel/transformation/transformers/es6/for-of.js

@@ -1,6 +1,6 @@
 import * as messages from "../../../messages";
 import * as util from  "../../../util";
-import t from "../../../types";
+import * as t from "../../../types";
 
 export var check = t.isForOfStatement;
 
@@ -32,40 +32,10 @@ export function ForOfStatement(node, parent, scope, file) {
   // todo: find out why this is necessary? #538
   loop._scopeInfo = node._scopeInfo;
 
-  if (build.replaceParent) {
-    this.parentPath.node = build.node;
-  } else {
-    return build.node;
-  }
+  if (build.replaceParent) this.parentPath.node = build.node;
+  return build.node;
 }
 
-var breakVisitor = {
-  enter(node, parent, scope, state) {
-    if (this.isLoop()) {
-      state.ignoreLabeless = true;
-      scope.traverse(node, breakVisitor, state);
-      state.ignoreLabeless = false;
-      return this.skip();
-    }
-
-    if (this.isBreakStatement()) {
-      if (!node.label && state.ignoreLabeless) return;
-      if (node.label && node.label.name !== state.label) return;
-
-      // break statements mean something different in this context
-      if (t.isSwitchCase(parent)) return;
-
-      var ret = t.expressionStatement(
-        t.callExpression(t.memberExpression(state.iteratorKey, t.identifier("return")), [])
-      );
-      ret = state.wrapReturn(ret);
-
-      this.skip();
-      return [ret, node];
-    }
-  }
-};
-
 var loose = function (node, parent, scope, file) {
   var left = node.left;
   var declar, id;
@@ -102,23 +72,6 @@ var loose = function (node, parent, scope, file) {
 
   //
 
-  scope.traverse(node, breakVisitor, {
-    iteratorKey: iteratorKey,
-    label:       t.isLabeledStatement(parent) && parent.label.name,
-
-    wrapReturn(node) {
-      return t.ifStatement(
-        t.logicalExpression(
-          "&&",
-          t.unaryExpression("!", isArrayKey, true),
-          t.memberExpression(iteratorKey, t.identifier("return")
-        )
-      ), node);
-    }
-  });
-
-  //
-
   return {
     declar: declar,
     node:   loop,
@@ -170,17 +123,6 @@ var spec = function (node, parent, scope, file) {
 
   //
 
-  scope.traverse(node, breakVisitor, {
-    iteratorKey: iteratorKey,
-    label:       isLabeledParent && parent.label.name,
-
-    wrapReturn(node) {
-      return t.ifStatement(t.memberExpression(iteratorKey, t.identifier("return")), node);
-    }
-  });
-
-  //
-
   return {
     replaceParent: isLabeledParent,
     declar:        declar,

src/babel/transformation/transformers/es6/modules.js

@@ -1,4 +1,4 @@
-import t from "../../../types";
+import * as t from "../../../types";
 
 export { check } from "../internal/modules";
 

src/babel/transformation/transformers/es6/object-super.js

@@ -1,5 +1,5 @@
 import ReplaceSupers from "../../helpers/replace-supers";
-import t from "../../../types";
+import * as t from "../../../types";
 
 export function check(node) {
   return t.isIdentifier(node, { name: "super" });
@@ -40,10 +40,7 @@ export function ObjectExpression(node, parent, scope, file) {
   }
 
   if (objectRef) {
-    scope.push({
-      id: objectRef
-    });
-
+    scope.push({ id: objectRef });
     return t.assignmentExpression("=", objectRef, node);
   }
 }

src/babel/transformation/transformers/es6/parameters.default.js

@@ -1,5 +1,5 @@
 import * as util from  "../../../util";
-import t from "../../../types";
+import * as t from "../../../types";
 
 export function check(node) {
   return t.isFunction(node) && hasDefaults(node);

src/babel/transformation/transformers/es6/parameters.rest.js

@@ -1,6 +1,6 @@
 import isNumber from "lodash/lang/isNumber";
 import * as util from  "../../../util";
-import t from "../../../types";
+import * as t from "../../../types";
 
 export var check = t.isRestElement;
 

src/babel/transformation/transformers/es6/properties.computed.js

@@ -1,4 +1,4 @@
-import t from "../../../types";
+import * as t from "../../../types";
 
 function loose(node, body, objId) {
   for (var i = 0; i < node.properties.length; i++) {

src/babel/transformation/transformers/es6/properties.shorthand.js

@@ -1,4 +1,4 @@
-import t from "../../../types";
+import * as t from "../../../types";
 
 export function check(node) {
   return t.isProperty(node) && (node.method || node.shorthand);

src/babel/transformation/transformers/es6/regex.sticky.js

@@ -1,5 +1,5 @@
 import * as regex from "../../helpers/regex";
-import t from "../../../types";
+import * as t from "../../../types";
 
 export function check(node) {
   return regex.is(node, "y");

src/babel/transformation/transformers/es6/regex.unicode.js

@@ -7,6 +7,6 @@ export function check(node) {
 
 export function Literal(node) {
   if (!regex.is(node, "u")) return;
-  regex.pullFlag(node, "y");
   node.regex.pattern = rewritePattern(node.regex.pattern, node.regex.flags);
+  regex.pullFlag(node, "u");
 }

src/babel/transformation/transformers/es6/spread.js

@@ -1,5 +1,5 @@
 import includes from "lodash/collection/includes";
-import t from "../../../types";
+import * as t from "../../../types";
 
 function getSpreadLiteral(spread, scope) {
   return scope.toArray(spread.argument, true);

src/babel/transformation/transformers/es6/symbols.js

@@ -1,4 +1,4 @@
-import t from "../../../types";
+import * as t from "../../../types";
 
 export var optional = true;
 

src/babel/transformation/transformers/es6/tail-call.js

@@ -3,7 +3,7 @@ import * as messages from "../../../messages";
 import flatten from "lodash/array/flatten";
 import * as util from  "../../../util";
 import map from "lodash/collection/map";
-import t from "../../../types";
+import * as t from "../../../types";
 
 exports.Function = function (node, parent, scope, file) {
   var tailCall = new TailCallTransformer(node, scope, file);
@@ -161,7 +161,7 @@ class TailCallTransformer {
     if (!this.hasTailRecursion) return;
 
     if (this.hasDeopt()) {
-      this.file.logDeopt(node, messages.get("tailCallReassignmentDeopt"));
+      this.file.log.deopt(node, messages.get("tailCallReassignmentDeopt"));
       return;
     }
 

src/babel/transformation/transformers/es6/template-literals.js

@@ -1,4 +1,4 @@
-import t from "../../../types";
+import * as t from "../../../types";
 
 var buildBinaryExpression = function (left, right) {
   return t.binaryExpression("+", left, right);

src/babel/transformation/transformers/es7/abstract-references.js

@@ -1,7 +1,7 @@
 // https://github.com/zenparsing/es-abstract-refs
 
 import * as util from  "../../../util";
-import t from "../../../types";
+import * as t from "../../../types";
 
 export var experimental = true;
 
@@ -24,6 +24,7 @@ var container = function (parent, call, ret, file) {
 export function AssignmentExpression(node, parent, scope, file) {
   var left = node.left;
   if (!t.isVirtualPropertyExpression(left)) return;
+  console.error("Abstract references are deprecated and will be removed in 5.0.0");
 
   var value = node.right;
   var temp;
@@ -65,6 +66,7 @@ export function UnaryExpression(node, parent, scope, file) {
   var arg = node.argument;
   if (!t.isVirtualPropertyExpression(arg)) return;
   if (node.operator !== "delete") return;
+  console.error("Abstract references are deprecated and will be removed in 5.0.0");
 
   var call = util.template("abstract-expression-delete", {
     PROPERTY: arg.property,
@@ -77,6 +79,7 @@ export function UnaryExpression(node, parent, scope, file) {
 export function CallExpression(node, parent, scope) {
   var callee = node.callee;
   if (!t.isVirtualPropertyExpression(callee)) return;
+  console.error("Abstract references are deprecated and will be removed in 5.0.0");
 
   var temp = scope.generateTempBasedOnNode(callee.object);
 
@@ -98,6 +101,7 @@ export function CallExpression(node, parent, scope) {
 }
 
 export function VirtualPropertyExpression(node) {
+  console.error("Abstract references are deprecated and will be removed in 5.0.0");
   return util.template("abstract-expression-get", {
     PROPERTY: node.property,
     OBJECT:   node.object
@@ -105,6 +109,7 @@ export function VirtualPropertyExpression(node) {
 }
 
 export function PrivateDeclaration(node) {
+  console.error("Abstract references are deprecated and will be removed in 5.0.0");
   return t.variableDeclaration("const", node.declarations.map(function (id) {
     return t.variableDeclarator(id, t.newExpression(t.identifier("WeakMap"), []));
   }));

src/babel/transformation/transformers/es7/comprehensions.js

@@ -1,7 +1,7 @@
 import buildComprehension from "../../helpers/build-comprehension";
 import traverse from "../../../traversal";
 import * as util from  "../../../util";
-import t from "../../../types";
+import * as t from "../../../types";
 
 export var experimental = true;
 

src/babel/transformation/transformers/es7/exponentiation-operator.js

@@ -1,7 +1,7 @@
 // https://github.com/rwaldron/exponentiation-operator
 
 import build from "../../helpers/build-binary-assignment-operator-transformer";
-import t from "../../../types";
+import * as t from "../../../types";
 
 export var experimental = true;
 

src/babel/transformation/transformers/es7/object-rest-spread.js

@@ -1,6 +1,6 @@
 // https://github.com/sebmarkbage/ecmascript-rest-spread
 
-import t from "../../../types";
+import * as t from "../../../types";
 
 export var experimental = true;
 

src/babel/transformation/transformers/index.js

@@ -94,7 +94,7 @@ export default {
 
   _aliasFunctions:                         require("./internal/alias-functions"),
 
-  "spec.typeofSymbol":                     require("./spec/typeof-symbol"),
+  "es6.symbols":                           require("./es6/symbols"),
   "spec.undefinedToVoid":                  require("./spec/undefined-to-void"),
 
   _strict:                                 require("./internal/strict"),

src/babel/transformation/transformers/internal/alias-functions.js

@@ -1,4 +1,4 @@
-import t from "../../../types";
+import * as t from "../../../types";
 
 var functionChildrenVisitor = {
   enter(node, parent, scope, state) {

src/babel/transformation/transformers/internal/cleanup.js

@@ -13,3 +13,18 @@ export var ExpressionStatement = {
     if (!node.expression) this.remove();
   }
 };
+
+export var Binary = {
+  exit(node) {
+    var right = node.right;
+    var left  = node.left;
+
+    if (!left && !right) {
+      this.remove();
+    } else if (!left) {
+      return right;
+    } else if (!right) {
+      return left;
+    }
+  }
+};

src/babel/transformation/transformers/internal/declarations.js

@@ -1,5 +1,5 @@
 import * as strict from "../../helpers/strict";
-import t from "../../../types";
+import * as t from "../../../types";
 
 export var secondPass = true;
 

src/babel/transformation/transformers/internal/modules.js

@@ -4,7 +4,7 @@
 // a generator function as a default then regenerator will destroy the export
 // declaration and leave a variable declaration in it's place... yeah, handy.
 
-import t from "../../../types";
+import * as t from "../../../types";
 
 export function check(node) {
   return t.isImportDeclaration(node) || t.isExportDeclaration(node);
@@ -32,9 +32,11 @@ export function ExportDeclaration(node, parent, scope) {
 
   if (node.default) {
     if (t.isClassDeclaration(declar)) {
+      // export default class Foo {};
+      this.node = [getDeclar(), node];
       node.declaration = declar.id;
-      return [getDeclar(), node];
     } else if (t.isClassExpression(declar)) {
+      // export default class {};
       var temp = scope.generateUidIdentifier("default");
       declar = t.variableDeclaration("var", [
         t.variableDeclarator(temp, declar)
@@ -42,25 +44,26 @@ export function ExportDeclaration(node, parent, scope) {
       node.declaration = temp;
       return [getDeclar(), node];
     } else if (t.isFunctionDeclaration(declar)) {
+      // export default function Foo() {}
       node._blockHoist = 2;
       node.declaration = declar.id;
       return [getDeclar(), node];
     }
   } else {
     if (t.isFunctionDeclaration(declar)) {
+      // export function Foo() {}
       node.specifiers  = [t.importSpecifier(declar.id, declar.id)];
       node.declaration = null;
       node._blockHoist = 2;
       return [getDeclar(), node];
     } else if (t.isVariableDeclaration(declar)) {
+      // export var foo = "bar";
       var specifiers = [];
-
       var bindings = t.getBindingIdentifiers(declar);
       for (var key in bindings) {
         var id = bindings[key];
         specifiers.push(t.exportSpecifier(id, id));
       }
-
       return [declar, t.exportDeclaration(null, specifiers)];
     }
   }

src/babel/transformation/transformers/internal/strict.js

@@ -1,7 +1,18 @@
-import t from "../../../types";
+import * as t from "../../../types";
 
 export function Program(program, parent, scope, file) {
   if (file.transformers.strict.canRun()) {
-    program.body.unshift(t.expressionStatement(t.literal("use strict")));
+    var directive = file.get("existingStrictDirective");
+
+    if (!directive) {
+      directive = t.expressionStatement(t.literal("use strict"));
+      var first = program.body[0];
+      if (first) {
+        directive.leadingComments = first.leadingComments;
+        first.leadingComments = [];
+      }
+    }
+
+    program.body.unshift(directive);
   }
 }

src/babel/transformation/transformers/internal/validation.js

@@ -1,5 +1,5 @@
 import * as messages from "../../../messages";
-import t from "../../../types";
+import * as t from "../../../types";
 
 export function ForOfStatement(node, parent, scope, file) {
   var left = node.left;
@@ -25,3 +25,16 @@ export function Property(node, parent, scope, file) {
 }
 
 export { Property as MethodDefinition };
+
+export function BlockStatement(node) {
+  for (var i = 0; i < node.body.length; i++) {
+    var bodyNode = node.body[i];
+    if (t.isExpressionStatement(bodyNode) && t.isLiteral(bodyNode.expression)) {
+      bodyNode._blockHoist = Infinity;
+    } else {
+      return;
+    }
+  }
+}
+
+export { BlockStatement as Program };

src/babel/transformation/transformers/other/bluebird-coroutines.js

@@ -1,5 +1,5 @@
 import remapAsyncToGenerator from "../../helpers/remap-async-to-generator";
-import t from "../../../types";
+import * as t from "../../../types";
 
 export function manipulateOptions(opts) {
   opts.experimental = true;

src/babel/transformation/transformers/other/flow.js

@@ -1,4 +1,4 @@
-import t from "../../../types";
+import * as t from "../../../types";
 
 export function Flow(node) {
   this.remove();

src/babel/transformation/transformers/other/react-compat.js

@@ -1,5 +1,5 @@
 import * as react from "../../helpers/react";
-import t from "../../../types";
+import * as t from "../../../types";
 
 export function manipulateOptions(opts) {
   opts.blacklist.push("react");

src/babel/transformation/transformers/other/react.js

@@ -1,5 +1,5 @@
 import * as react from "../../helpers/react";
-import t from "../../../types";
+import * as t from "../../../types";
 
 var JSX_ANNOTATION_REGEX = /^\*\s*@jsx\s+([^\s]+)/;
 

src/babel/transformation/transformers/other/regenerator.js

@@ -1,5 +1,5 @@
 import regenerator from "regenerator-babel";
-import t from "../../../types";
+import * as t from "../../../types";
 
 export function check(node) {
   return t.isFunction(node) && (node.async || node.generator);

src/babel/transformation/transformers/other/runtime.js

@@ -2,7 +2,7 @@ import includes from "lodash/collection/includes";
 import * as util from  "../../../util";
 import core from "core-js/library";
 import has from "lodash/object/has";
-import t from "../../../types";
+import * as t from "../../../types";
 
 var isSymboliterator = t.buildMatchMemberExpression("Symbol.iterator");
 
@@ -16,8 +16,7 @@ var ALIASABLE_CONSTRUCTORS = [
   "Map",
   "WeakMap",
   "Set",
-  "WeakSet",
-  "Number"
+  "WeakSet"
 ];
 
 var astVisitor = {
@@ -81,8 +80,8 @@ export function Program(node, parent, scope, file) {
 }
 
 export function pre(file) {
-  file.setDynamic("helpersNamespace", function () {
-    return file.addImport("babel-runtime/helpers", "babelHelpers");
+  file.set("helperGenerator", function (name) {
+    return file.addImport("babel-runtime/helpers/" + name, name);
   });
 
   file.setDynamic("coreIdentifier", function () {

src/babel/transformation/transformers/other/strict.js

@@ -1,10 +1,10 @@
 import * as messages from "../../../messages";
-import t from "../../../types";
+import * as t from "../../../types";
 
-export function Program(program) {
+export function Program(program, parent, scope, file) {
   var first = program.body[0];
   if (t.isExpressionStatement(first) && t.isLiteral(first.expression, { value: "use strict" })) {
-    program.body.shift();
+    file.set("existingStrictDirective", program.body.shift());
   }
 }