Allow functions to return, yield, and await within comprehensions

Author: rattrayalex

src/index.js

@@ -214,6 +214,9 @@ export default function (babel) {
 
  function validateComprehensionLoopBody(loopBodyPath) {
  loopBodyPath.traverse({
+ Function(fnPath) {
+ fnPath.skip();
+ },
  AwaitExpression(awaitPath) {
  throw awaitPath.buildCodeFrameError(
  "`await` is not allowed within Comprehensions; " +

test/fixtures/comprehensions/return-inside-fn/actual.js

@@ -0,0 +1,4 @@
+f() ->
+ c = [for const x of arr:
+ g() -> return x
+ ]

test/fixtures/comprehensions/return-inside-fn/expected.js

@@ -0,0 +1,13 @@
+function f() {
+ const c = (() => {
+ const _arr = [];
+ for (const x of arr) {
+ function g() {
+ return x;
+ }
+
+ _arr.push(g);
+ }return _arr;
+ })();
+ return c;
+}