Backport babel#7312 for 6.x

packages/babel-core/src/transformation/internal-plugins/shadow-functions.js

@@ -91,29 +91,33 @@ function remap(path, key) {
   // binding since arrow function syntax already does that.
   if (!passedShadowFunction) return;
 
-  const cached = fnPath.getData(key);
-  if (cached) return path.replaceWith(cached);
+  let cached = fnPath.getData(key);
+  if (!cached) {
+    const id = path.scope.generateUidIdentifier(key);
 
-  const id   = path.scope.generateUidIdentifier(key);
+    fnPath.setData(key, id);
+    cached = id;
 
-  fnPath.setData(key, id);
+    const classPath = fnPath.findParent((p) => p.isClass());
+    const hasSuperClass = !!(classPath && classPath.node && classPath.node.superClass);
 
-  const classPath = fnPath.findParent((p) => p.isClass());
-  const hasSuperClass = !!(classPath && classPath.node && classPath.node.superClass);
+    if (key === "this" && fnPath.isMethod({ kind: "constructor" }) && hasSuperClass) {
+      fnPath.scope.push({ id });
 
-  if (key === "this" && fnPath.isMethod({ kind: "constructor" }) && hasSuperClass) {
-    fnPath.scope.push({ id });
+      fnPath.traverse(superVisitor, { id });
+    } else {
+      const init = key === "this" ? t.thisExpression() : t.identifier(key);
 
-    fnPath.traverse(superVisitor, { id });
-  } else {
-    const init = key === "this" ? t.thisExpression() : t.identifier(key);
-
-    // Forward the shadowed function, so that the identifiers do not get hoisted
-    // up to the first non shadow function but rather up to the bound shadow function
-    if (shadowFunction) init._shadowedFunctionLiteral = shadowFunction;
+      // Forward the shadowed function, so that the identifiers do not get hoisted
+      // up to the first non shadow function but rather up to the bound shadow function
+      if (shadowFunction) init._shadowedFunctionLiteral = shadowFunction;
 
-    fnPath.scope.push({ id, init });
+      fnPath.scope.push({ id, init });
+    }
   }
 
-  return path.replaceWith(id);
+  const node = t.cloneDeep(cached);
+  node.loc = path.node.loc;
+
+  return path.replaceWith(node);
 }

packages/babel-plugin-transform-es2015-arrow-functions/test/fixtures/arrow-functions/arguments-source-maps/actual.js

@@ -0,0 +1,5 @@
+function fn() {
+  var inner = () => {
+    console.log(arguments);
+  };
+}

packages/babel-plugin-transform-es2015-arrow-functions/test/fixtures/arrow-functions/arguments-source-maps/expected.js

@@ -0,0 +1,7 @@
+function fn() {
+  var _arguments = arguments;
+
+  var inner = function () {
+    console.log(_arguments);
+  };
+}

packages/babel-plugin-transform-es2015-arrow-functions/test/fixtures/arrow-functions/arguments-source-maps/options.json

@@ -0,0 +1,3 @@
+{
+  "plugins": ["transform-es2015-arrow-functions"]
+}

packages/babel-plugin-transform-es2015-arrow-functions/test/fixtures/arrow-functions/arguments-source-maps/source-map.json

@@ -0,0 +1,18 @@
+{
+  "file": "arrow-functions/arguments-source-maps/expected.js",
+  "mappings": "AAAA,SAASA,EAAT,GAAc;AAAA;;AACZ,MAAIC,QAAQ,YAAM;AAChBC,YAAQC,GAAR,CAAYC,UAAZ;AACD,GAFD;AAGD",
+  "names": [
+    "fn",
+    "inner",
+    "console",
+    "log",
+    "arguments"
+  ],
+  "sources": [
+    "arrow-functions/arguments-source-maps/actual.js"
+  ],
+  "sourcesContent": [
+    "function fn() {\n  var inner = () => {\n    console.log(arguments);\n  };\n}"
+  ],
+  "version": 3
+}

packages/babel-plugin-transform-es2015-arrow-functions/test/fixtures/arrow-functions/arguments-source-maps/source-mappings.json

@@ -0,0 +1,8 @@
+[{
+  "generated": {
+    "line": 5, "column": 16
+  },
+  "original": {
+    "line": 3, "column": 16
+  }
+}]

packages/babel-plugin-transform-es2015-arrow-functions/test/fixtures/arrow-functions/this-source-maps/actual.js

@@ -0,0 +1,5 @@
+function fn() {
+  var inner = () => {
+    console.log(this);
+  };
+}

packages/babel-plugin-transform-es2015-arrow-functions/test/fixtures/arrow-functions/this-source-maps/expected.js

@@ -0,0 +1,7 @@
+function fn() {
+  var _this = this;
+
+  var inner = function () {
+    console.log(_this);
+  };
+}

packages/babel-plugin-transform-es2015-arrow-functions/test/fixtures/arrow-functions/this-source-maps/options.json

@@ -0,0 +1,3 @@
+{
+  "plugins": ["transform-es2015-arrow-functions"]
+}

packages/babel-plugin-transform-es2015-arrow-functions/test/fixtures/arrow-functions/this-source-maps/source-map.json

@@ -0,0 +1,17 @@
+{
+  "file": "arrow-functions/this-source-maps/expected.js",
+  "mappings": "AAAA,SAASA,EAAT,GAAc;AAAA;;AACZ,MAAIC,QAAQ,YAAM;AAChBC,YAAQC,GAAR,CAAY,KAAZ;AACD,GAFD;AAGD",
+  "names": [
+    "fn",
+    "inner",
+    "console",
+    "log"
+  ],
+  "sources": [
+    "arrow-functions/this-source-maps/actual.js"
+  ],
+  "sourcesContent": [
+    "function fn() {\n  var inner = () => {\n    console.log(this);\n  };\n}"
+  ],
+  "version": 3
+}

packages/babel-plugin-transform-es2015-arrow-functions/test/fixtures/arrow-functions/this-source-maps/source-mappings.json

@@ -0,0 +1,8 @@
+[{
+  "generated": {
+    "line": 5, "column": 16
+  },
+  "original": {
+    "line": 3, "column": 16
+  }
+}]