Merge pull request #4789 from guybedford/system-dynamic-import

Support import() as contextual import in system module format

packages/babel-plugin-transform-es2015-modules-systemjs/package.json

@@ -14,6 +14,7 @@
     "babel-plugin"
   ],
   "devDependencies": {
-    "babel-helper-plugin-test-runner": "^6.18.0"
+    "babel-helper-plugin-test-runner": "^6.18.0",
+    "babel-plugin-syntax-dynamic-import": "^6.18.0"
   }
 }

packages/babel-plugin-transform-es2015-modules-systemjs/src/index.js

@@ -22,6 +22,9 @@ let buildExportAll = template(`
   }
 `);
 
+
+const TYPE_IMPORT = "Import";
+
 export default function ({ types: t }) {
   let IGNORE_REASSIGNMENT_SYMBOL = Symbol();
 
@@ -69,6 +72,14 @@ export default function ({ types: t }) {
 
   return {
     visitor: {
+
+      CallExpression(path, state) {
+        if (path.node.callee.type === TYPE_IMPORT) {
+          let contextIdent = state.contextIdent;
+          path.replaceWith(t.callExpression(t.memberExpression(contextIdent, t.identifier("import")), path.node.arguments));
+        }
+      },
+
       ReferencedIdentifier(path, state) {
         if (path.node.name == "__moduleName" && !path.scope.hasBinding("__moduleName")) {
           path.replaceWith(t.memberExpression(state.contextIdent, t.identifier("id")));

packages/babel-plugin-transform-es2015-modules-systemjs/test/fixtures/dynamic-import/dynamic-import/actual.js

@@ -0,0 +1,6 @@
+export function lazyLoadOperation () {
+  return import('./x')
+  .then(function (x) {
+    x.y();
+  });
+}

packages/babel-plugin-transform-es2015-modules-systemjs/test/fixtures/dynamic-import/dynamic-import/expected.js

@@ -0,0 +1,16 @@
+System.register([], function (_export, _context) {
+  "use strict";
+
+  function lazyLoadOperation() {
+    return _context.import('./x').then(function (x) {
+      x.y();
+    });
+  }
+
+  _export('lazyLoadOperation', lazyLoadOperation);
+
+  return {
+    setters: [],
+    execute: function () {}
+  };
+});

packages/babel-plugin-transform-es2015-modules-systemjs/test/fixtures/dynamic-import/options.json

@@ -0,0 +1,3 @@
+{
+  "plugins": ["external-helpers", "syntax-dynamic-import", "transform-es2015-modules-systemjs"]
+}