Merge pull request #6335 from jridgewell/pipeline

Pipeline operator

package.json

@@ -19,7 +19,7 @@
     "babel-preset-flow": "7.0.0-alpha.18",
     "babel-preset-stage-0": "7.0.0-alpha.18",
     "babel-register": "7.0.0-alpha.18",
-    "babylon": "7.0.0-beta.26",
+    "babylon": "7.0.0-beta.27",
     "browserify": "^13.1.1",
     "bundle-collapser": "^1.2.1",
     "chai": "^4.1.0",

packages/babel-core/package.json

@@ -31,7 +31,7 @@
     "babel-template": "7.0.0-beta.2",
     "babel-traverse": "7.0.0-beta.2",
     "babel-types": "7.0.0-beta.2",
-    "babylon": "7.0.0-beta.26",
+    "babylon": "7.0.0-beta.27",
     "convert-source-map": "^1.1.0",
     "debug": "^3.0.1",
     "json5": "^0.5.0",

packages/babel-generator/package.json

@@ -19,6 +19,6 @@
   },
   "devDependencies": {
     "babel-helper-fixtures": "7.0.0-beta.2",
-    "babylon": "^7.0.0-beta.26"
+    "babylon": "^7.0.0-beta.27"
   }
 }

packages/babel-plugin-syntax-pipeline-operator/README.md

@@ -0,0 +1,35 @@
+# babel-plugin-syntax-pipeline-operator
+
+Allow parsing of the pipeline operator `|>`. See [the proposal](https://github.com/tc39/proposal-pipeline-operator) for details.
+
+## Installation
+
+```sh
+$ npm install babel-plugin-syntax-pipeline-operator
+```
+
+## Usage
+
+### Via `.babelrc` (Recommended)
+
+**.babelrc**
+
+```json
+{
+  "plugins": ["syntax-pipeline-operator"]
+}
+```
+
+### Via CLI
+
+```sh
+$ babel --plugins syntax-pipeline-operator script.js
+```
+
+### Via Node API
+
+```javascript
+require("babel-core").transform("code", {
+  plugins: ["syntax-pipeline-operator"]
+});
+```

packages/babel-plugin-syntax-pipeline-operator/package.json

@@ -0,0 +1,11 @@
+{
+  "name": "babel-plugin-syntax-pipeline-operator",
+  "version": "7.0.0-beta.2",
+  "description": "Allow parsing of the pipeline operator",
+  "repository": "https://github.com/babel/babel/tree/master/packages/babel-plugin-syntax-pipeline-operator",
+  "license": "MIT",
+  "main": "lib/index.js",
+  "keywords": [
+    "babel-plugin"
+  ]
+}

packages/babel-plugin-syntax-pipeline-operator/src/index.js

@@ -0,0 +1,7 @@
+export default function() {
+  return {
+    manipulateOptions(opts, parserOpts) {
+      parserOpts.plugins.push("pipelineOperator");
+    },
+  };
+}

packages/babel-plugin-transform-pipeline-operator/README.md

@@ -0,0 +1,35 @@
+# babel-plugin-transform-pipeline-operator
+
+Transform pipeline operator `|>` into call expressions. See [the proposal](https://github.com/tc39/proposal-pipeline-operator) for details.
+
+## Installation
+
+```sh
+$ npm install babel-plugin-transform-pipeline-operator
+```
+
+## Usage
+
+### Via `.babelrc` (Recommended)
+
+**.babelrc**
+
+```json
+{
+  "plugins": ["transform-pipeline-operator"]
+}
+```
+
+### Via CLI
+
+```sh
+$ babel --plugins transform-pipeline-operator script.js
+```
+
+### Via Node API
+
+```javascript
+require("babel-core").transform("code", {
+  plugins: ["transform-pipeline-operator"]
+});
+```

packages/babel-plugin-transform-pipeline-operator/package.json

@@ -0,0 +1,17 @@
+{
+  "name": "babel-plugin-transform-pipeline-operator",
+  "version": "7.0.0-beta.2",
+  "description": "Transform pipeline operator into call expressions",
+  "repository": "https://github.com/babel/babel/tree/master/packages/babel-plugin-transform-pipeline-operator",
+  "license": "MIT",
+  "main": "lib/index.js",
+  "keywords": [
+    "babel-plugin"
+  ],
+  "dependencies": {
+    "babel-plugin-syntax-pipeline-operator": "7.0.0-beta.2"
+  },
+  "devDependencies": {
+    "babel-helper-plugin-test-runner": "7.0.0-beta.2"
+  }
+}

packages/babel-plugin-transform-pipeline-operator/src/index.js

@@ -0,0 +1,56 @@
+import syntaxPipelineOperator from "babel-plugin-syntax-pipeline-operator";
+
+export default function({ types: t }) {
+  return {
+    inherits: syntaxPipelineOperator,
+
+    visitor: {
+      BinaryExpression(path) {
+        const { scope } = path;
+        const { node } = path;
+        const { operator, left } = node;
+        let { right } = node;
+        if (operator !== "|>") return;
+
+        let optimizeArrow =
+          t.isArrowFunctionExpression(right) && t.isExpression(right.body);
+        let param;
+
+        if (optimizeArrow) {
+          const { params } = right;
+          if (params.length === 1) {
+            param = params[0];
+          } else if (params.length > 1) {
+            optimizeArrow = false;
+          }
+        } else if (t.isIdentifier(right, { name: "eval" })) {
+          right = t.sequenceExpression([t.numericLiteral(0), right]);
+        }
+
+        if (optimizeArrow && !param) {
+          // Arrow function with 0 arguments
+          path.replaceWith(t.sequenceExpression([left, right.body]));
+          return;
+        }
+
+        const placeholder = scope.generateUidIdentifierBasedOnNode(
+          param || left,
+        );
+        scope.push({ id: placeholder });
+        if (param) {
+          path.get("right").scope.rename(param.name, placeholder.name);
+        }
+
+        const call = optimizeArrow
+          ? right.body
+          : t.callExpression(right, [placeholder]);
+        path.replaceWith(
+          t.sequenceExpression([
+            t.assignmentExpression("=", placeholder, left),
+            call,
+          ]),
+        );
+      },
+    },
+  };
+}

packages/babel-plugin-transform-pipeline-operator/test/fixtures/pipeline-operator/arrow-functions/actual.js

@@ -0,0 +1,14 @@
+var result = [5,10]
+  |> _ => _.map(x => x * 2)
+  |> _ => _.reduce( (a,b) => a + b )
+  |> sum => sum + 1
+
+assert.equal(result, 31)
+
+
+var inc = (x) => x + 1;
+var double = (x) => x * 2;
+
+var result2 = [4, 9].map( x => x |> inc |> double )
+
+assert.deepEqual(result2, [10, 20])

packages/babel-plugin-transform-pipeline-operator/test/fixtures/pipeline-operator/arrow-functions/exec.js

@@ -0,0 +1,14 @@
+var result = [5,10]
+  |> _ => _.map(x => x * 2)
+  |> _ => _.reduce( (a,b) => a + b )
+  |> sum => sum + 1
+
+assert.equal(result, 31)
+
+
+var inc = (x) => x + 1;
+var double = (x) => x * 2;
+
+var result2 = [4, 9].map( x => x |> inc |> double )
+
+assert.deepEqual(result2, [10, 20])

packages/babel-plugin-transform-pipeline-operator/test/fixtures/pipeline-operator/arrow-functions/expected.js

@@ -0,0 +1,15 @@
+var _ref, _ref2, _sum;
+
+var result = (_ref = [5, 10], (_ref2 = _ref.map(x => x * 2), (_sum = _ref2.reduce((a, b) => a + b), _sum + 1)));
+assert.equal(result, 31);
+
+var inc = x => x + 1;
+
+var double = x => x * 2;
+
+var result2 = [4, 9].map(x => {
+  var _ref3, _x;
+
+  return _ref3 = (_x = x, inc(_x)), double(_ref3);
+});
+assert.deepEqual(result2, [10, 20]);

packages/babel-plugin-transform-pipeline-operator/test/fixtures/pipeline-operator/basic/actual.js

@@ -0,0 +1,3 @@
+var inc = (x) => x + 1
+
+assert.equal(10 |> inc, 11);

packages/babel-plugin-transform-pipeline-operator/test/fixtures/pipeline-operator/basic/exec.js

@@ -0,0 +1,3 @@
+var inc = (x) => x + 1
+
+assert.equal(10 |> inc, 11);

packages/babel-plugin-transform-pipeline-operator/test/fixtures/pipeline-operator/basic/expected.js

@@ -0,0 +1,5 @@
+var _;
+
+var inc = x => x + 1;
+
+assert.equal((_ = 10, inc(_)), 11);

packages/babel-plugin-transform-pipeline-operator/test/fixtures/pipeline-operator/chaining/actual.js

@@ -0,0 +1,4 @@
+var inc = (x) => x + 1;
+var double = (x) => x * 2;
+
+assert.equal(10 |> inc |> double, 22);

packages/babel-plugin-transform-pipeline-operator/test/fixtures/pipeline-operator/chaining/exec.js

@@ -0,0 +1,4 @@
+var inc = (x) => x + 1;
+var double = (x) => x * 2;
+
+assert.equal(10 |> inc |> double, 22);

packages/babel-plugin-transform-pipeline-operator/test/fixtures/pipeline-operator/chaining/expected.js

@@ -0,0 +1,7 @@
+var _ref, _;
+
+var inc = x => x + 1;
+
+var double = x => x * 2;
+
+assert.equal((_ref = (_ = 10, inc(_)), double(_ref)), 22);

packages/babel-plugin-transform-pipeline-operator/test/fixtures/pipeline-operator/currying/actual.js

@@ -0,0 +1,6 @@
+
+var map = (fn) => (array) => array.map(fn);
+
+var result = [10,20] |> map(x => x * 20);
+
+assert.deepEqual(result, [200, 400])

packages/babel-plugin-transform-pipeline-operator/test/fixtures/pipeline-operator/currying/exec.js

@@ -0,0 +1,6 @@
+
+var map = (fn) => (array) => array.map(fn);
+
+var result = [10,20] |> map(x => x * 20);
+
+assert.deepEqual(result, [200, 400])

packages/babel-plugin-transform-pipeline-operator/test/fixtures/pipeline-operator/currying/expected.js

@@ -0,0 +1,6 @@
+var _ref;
+
+var map = fn => array => array.map(fn);
+
+var result = (_ref = [10, 20], map(x => x * 20)(_ref));
+assert.deepEqual(result, [200, 400]);

packages/babel-plugin-transform-pipeline-operator/test/fixtures/pipeline-operator/deoptimize-multi-param-arrow/actual.js

@@ -0,0 +1,8 @@
+var a = 1,
+    b = 2,
+    c = 3;
+var result = a
+  |> (a, b) => b
+  |> (a, b) => c;
+
+assert.equal(result, c)

packages/babel-plugin-transform-pipeline-operator/test/fixtures/pipeline-operator/deoptimize-multi-param-arrow/exec.js

@@ -0,0 +1,8 @@
+var a = 1,
+    b = 2,
+    c = 3;
+var result = a
+  |> (a, b) => b
+  |> (a, b) => c;
+
+assert.equal(result, c)

packages/babel-plugin-transform-pipeline-operator/test/fixtures/pipeline-operator/deoptimize-multi-param-arrow/expected.js

@@ -0,0 +1,11 @@
+var _a;
+
+var a = 1,
+    b = 2,
+    c = 3;
+var result = (_a = a, ((a, b) => {
+  var _b;
+
+  return _b = b, ((a, b) => c)(_b);
+})(_a));
+assert.equal(result, c);

packages/babel-plugin-transform-pipeline-operator/test/fixtures/pipeline-operator/evaluation/actual.js

@@ -0,0 +1,13 @@
+var obj = {
+  get prop() {
+    return this._prop = 1;
+  },
+
+  get method() {
+    if (!this._prop) throw new Error('invalid evaluation order');
+    return (v) => v;
+  }
+}
+
+var result = obj.prop |> obj.method;
+assert.equal(result, 1);

packages/babel-plugin-transform-pipeline-operator/test/fixtures/pipeline-operator/evaluation/exec.js

@@ -0,0 +1,13 @@
+var obj = {
+  get prop() {
+    return this._prop = 1;
+  },
+
+  get method() {
+    if (!this._prop) throw new Error('invalid evaluation order');
+    return (v) => v;
+  }
+}
+
+var result = obj.prop |> obj.method;
+assert.equal(result, 1);

packages/babel-plugin-transform-pipeline-operator/test/fixtures/pipeline-operator/evaluation/expected.js

@@ -0,0 +1,15 @@
+var _obj$prop;
+
+var obj = {
+  get prop() {
+    return this._prop = 1;
+  },
+
+  get method() {
+    if (!this._prop) throw new Error('invalid evaluation order');
+    return v => v;
+  }
+
+};
+var result = (_obj$prop = obj.prop, obj.method(_obj$prop));
+assert.equal(result, 1);

packages/babel-plugin-transform-pipeline-operator/test/fixtures/pipeline-operator/indirect-eval/actual.js

@@ -0,0 +1,7 @@
+(function() {
+  'use strict';
+  var result = '(function() { return this; })()'
+    |> eval;
+
+  assert.notEqual(result, undefined);
+})();

packages/babel-plugin-transform-pipeline-operator/test/fixtures/pipeline-operator/indirect-eval/exec.js

@@ -0,0 +1,7 @@
+(function() {
+  'use strict';
+  var result = '(function() { return this; })()'
+    |> eval;
+
+  assert.notEqual(result, undefined);
+})();

packages/babel-plugin-transform-pipeline-operator/test/fixtures/pipeline-operator/indirect-eval/expected.js

@@ -0,0 +1,8 @@
+(function () {
+  'use strict';
+
+  var _functionReturn;
+
+  var result = (_functionReturn = '(function() { return this; })()', (0, eval)(_functionReturn));
+  assert.notEqual(result, undefined);
+})();

packages/babel-plugin-transform-pipeline-operator/test/fixtures/pipeline-operator/multiple-argument-use/actual.js

@@ -0,0 +1,5 @@
+var array = [10,20,30];
+
+var last = array |> a => a[a.length-1];
+
+assert.equal(last, 30);

packages/babel-plugin-transform-pipeline-operator/test/fixtures/pipeline-operator/multiple-argument-use/exec.js

@@ -0,0 +1,5 @@
+var array = [10,20,30];
+
+var last = array |> a => a[a.length-1];
+
+assert.equal(last, 30);

packages/babel-plugin-transform-pipeline-operator/test/fixtures/pipeline-operator/multiple-argument-use/expected.js

@@ -0,0 +1,5 @@
+var _a;
+
+var array = [10, 20, 30];
+var last = (_a = array, _a[_a.length - 1]);
+assert.equal(last, 30);

packages/babel-plugin-transform-pipeline-operator/test/fixtures/pipeline-operator/optimize-0-param-arrow/actual.js

@@ -0,0 +1,8 @@
+var a = 1,
+    b = 2,
+    c = 3;
+var result = a
+  |> () => b
+  |> () => c;
+
+assert.equal(result, c)

packages/babel-plugin-transform-pipeline-operator/test/fixtures/pipeline-operator/optimize-0-param-arrow/exec.js

@@ -0,0 +1,8 @@
+var a = 1,
+    b = 2,
+    c = 3;
+var result = a
+  |> () => b
+  |> () => c;
+
+assert.equal(result, c)

packages/babel-plugin-transform-pipeline-operator/test/fixtures/pipeline-operator/optimize-0-param-arrow/expected.js

@@ -0,0 +1,5 @@
+var a = 1,
+    b = 2,
+    c = 3;
+var result = (a, (b, c));
+assert.equal(result, c);

packages/babel-plugin-transform-pipeline-operator/test/fixtures/pipeline-operator/options.json

@@ -0,0 +1,3 @@
+{
+  "plugins": ["transform-pipeline-operator"]
+}

packages/babel-plugin-transform-pipeline-operator/test/fixtures/pipeline-operator/precedence/actual.js

@@ -0,0 +1,12 @@
+
+var inc = (x) => x + 1;
+
+var result = 4 || 9 |> inc;
+assert.equal(result, 5);
+
+
+var f = (x) => x + 10
+var h = (x) => x + 20
+
+var result2 = 10 |> f || h |> inc;
+assert.equal(result2, 21);

packages/babel-plugin-transform-pipeline-operator/test/fixtures/pipeline-operator/precedence/exec.js

@@ -0,0 +1,12 @@
+
+var inc = (x) => x + 1;
+
+var result = 4 || 9 |> inc;
+assert.equal(result, 5);
+
+
+var f = (x) => x + 10
+var h = (x) => x + 20
+
+var result2 = 10 |> f || h |> inc;
+assert.equal(result2, 21);

packages/babel-plugin-transform-pipeline-operator/test/fixtures/pipeline-operator/precedence/expected.js

@@ -0,0 +1,13 @@
+var _ref, _ref2, _;
+
+var inc = x => x + 1;
+
+var result = (_ref = 4 || 9, inc(_ref));
+assert.equal(result, 5);
+
+var f = x => x + 10;
+
+var h = x => x + 20;
+
+var result2 = (_ref2 = (_ = 10, (f || h)(_)), inc(_ref2));
+assert.equal(result2, 21);

packages/babel-plugin-transform-pipeline-operator/test/index.js

@@ -0,0 +1,3 @@
+import runner from "babel-helper-plugin-test-runner";
+
+runner(__dirname);

packages/babel-preset-stage-1/package.json

@@ -11,6 +11,7 @@
     "babel-plugin-transform-decorators": "7.0.0-beta.2",
     "babel-plugin-transform-export-default": "7.0.0-beta.2",
     "babel-plugin-transform-optional-chaining": "7.0.0-beta.2",
+    "babel-plugin-transform-pipeline-operator": "7.0.0-beta.2",
     "babel-preset-stage-2": "7.0.0-beta.2"
   }
 }

packages/babel-preset-stage-1/src/index.js

@@ -3,6 +3,7 @@ import presetStage2 from "babel-preset-stage-2";
 import transformDecorators from "babel-plugin-transform-decorators";
 import transformExportDefault from "babel-plugin-transform-export-default";
 import transformOptionalChaining from "babel-plugin-transform-optional-chaining";
+import transformPipelineOperator from "babel-plugin-transform-pipeline-operator";
 
 export default function() {
   return {
@@ -11,6 +12,7 @@ export default function() {
       transformDecorators,
       transformExportDefault,
       transformOptionalChaining,
+      transformPipelineOperator,
     ],
   };
 }

packages/babel-template/package.json

@@ -10,7 +10,7 @@
   "dependencies": {
     "babel-traverse": "7.0.0-beta.2",
     "babel-types": "7.0.0-beta.2",
-    "babylon": "7.0.0-beta.26",
+    "babylon": "7.0.0-beta.27",
     "lodash": "^4.2.0"
   }
 }

packages/babel-traverse/package.json

@@ -11,7 +11,7 @@
     "babel-code-frame": "7.0.0-beta.2",
     "babel-helper-function-name": "7.0.0-beta.2",
     "babel-types": "7.0.0-beta.2",
-    "babylon": "7.0.0-beta.26",
+    "babylon": "7.0.0-beta.27",
     "debug": "^3.0.1",
     "globals": "^10.0.0",
     "invariant": "^2.2.0",

packages/babel-types/package.json

@@ -14,6 +14,6 @@
   },
   "devDependencies": {
     "babel-generator": "7.0.0-beta.2",
-    "babylon": "^7.0.0-beta.26"
+    "babylon": "^7.0.0-beta.27"
   }
 }

yarn.lock

@@ -1017,9 +1017,9 @@ babylon@7.0.0-beta.18:
   version "7.0.0-beta.18"
   resolved "https://registry.yarnpkg.com/babylon/-/babylon-7.0.0-beta.18.tgz#5c23ee3fdb66358aabf3789779319c5b78a233c7"
 
-babylon@7.0.0-beta.26:
+babylon@7.0.0-beta.27:
-  version "7.0.0-beta.26"
+  version "7.0.0-beta.27"
-  resolved "https://registry.yarnpkg.com/babylon/-/babylon-7.0.0-beta.26.tgz#afc2c6b86113d000cc9476fd6f73e2a9223de8f7"
+  resolved "https://registry.yarnpkg.com/babylon/-/babylon-7.0.0-beta.27.tgz#b6edd30ef30619e2f630eb52585fdda84e6542cd"
 
 babylon@^6.17.4, babylon@^6.18.0:
   version "6.18.0"