fix(javascript): do not attach to block if it's not behind right func paren (#5435)

src/common/util.js

@@ -196,9 +196,8 @@ function isNextLineEmpty(text, node, locEnd) {
   return isNextLineEmptyAfterIndex(text, locEnd(node));
 }
 
-function getNextNonSpaceNonCommentCharacterIndex(text, node, locEnd) {
+function getNextNonSpaceNonCommentCharacterIndexWithStartIndex(text, idx) {
   let oldIdx = null;
-  let idx = locEnd(node);
   while (idx !== oldIdx) {
     oldIdx = idx;
     idx = skipSpaces(text, idx);
@@ -209,6 +208,13 @@ function getNextNonSpaceNonCommentCharacterIndex(text, node, locEnd) {
   return idx;
 }
 
+function getNextNonSpaceNonCommentCharacterIndex(text, node, locEnd) {
+  return getNextNonSpaceNonCommentCharacterIndexWithStartIndex(
+    text,
+    locEnd(node)
+  );
+}
+
 function getNextNonSpaceNonCommentCharacter(text, node, locEnd) {
   return text.charAt(
     getNextNonSpaceNonCommentCharacterIndex(text, node, locEnd)
@@ -679,6 +685,7 @@ module.exports = {
   getParentExportDeclaration,
   getPenultimate,
   getLast,
+  getNextNonSpaceNonCommentCharacterIndexWithStartIndex,
   getNextNonSpaceNonCommentCharacterIndex,
   getNextNonSpaceNonCommentCharacter,
   skip,

src/language-js/comments.js

@@ -630,8 +630,26 @@ function handleLastFunctionArgComments(
     followingNode &&
     followingNode.type === "BlockStatement"
   ) {
-    addBlockStatementFirstComment(followingNode, comment);
-    return true;
+    const functionParamRightParenIndex = (() => {
+      if (enclosingNode.params.length !== 0) {
+        return privateUtil.getNextNonSpaceNonCommentCharacterIndexWithStartIndex(
+          text,
+          options.locEnd(privateUtil.getLast(enclosingNode.params))
+        );
+      }
+      const functionParamLeftParenIndex = privateUtil.getNextNonSpaceNonCommentCharacterIndexWithStartIndex(
+        text,
+        options.locEnd(enclosingNode.id)
+      );
+      return privateUtil.getNextNonSpaceNonCommentCharacterIndexWithStartIndex(
+        text,
+        functionParamLeftParenIndex + 1
+      );
+    })();
+    if (options.locStart(comment) > functionParamRightParenIndex) {
+      addBlockStatementFirstComment(followingNode, comment);
+      return true;
+    }
   }
 
   return false;

tests/flow_comments/babylon_only/__snapshots__/jsfmt.spec.js.snap

@@ -26,3 +26,17 @@ class Component extends React.Component /*:: <Props, State> */ {
 }
 
 `;
+
+exports[`functions.js - babylon-verify 1`] = `
+
+export function updateStoreFromURL(
+  store /*: Store*/,
+  {search, hash} /*: {search: string, hash: string}*/
+) {}
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+export function updateStoreFromURL(
+  store /*: Store*/,
+  { search, hash } /*: {search: string, hash: string}*/
+) {}
+
+`;

tests/flow_comments/babylon_only/functions.js

@@ -0,0 +1,5 @@
+
+export function updateStoreFromURL(
+  store /*: Store*/,
+  {search, hash} /*: {search: string, hash: string}*/
+) {}