From 664d0d33b519b093f2be3a35357debeecdf941e2 Mon Sep 17 00:00:00 2001
From: fisker Cheung <lionkay@gmail.com>
Date: Thu, 26 Nov 2020 19:30:57 +0800
Subject: [PATCH] Fix inconsistent language comment detection (#9743)

---
 changelog_unreleased/javascript/9743.md       | 19 +++++++++++++++++++
 src/language-js/comments.js                   | 15 ---------------
 src/language-js/embed.js                      |  9 ++++-----
 .../__snapshots__/jsfmt.spec.js.snap          | 19 +++++++++++++++++++
 .../language-comment/jsfmt.spec.js            |  1 +
 .../language-comment/not-language-comment.js  |  3 +++
 6 files changed, 46 insertions(+), 20 deletions(-)
 create mode 100644 changelog_unreleased/javascript/9743.md
 create mode 100644 tests/js/multiparser-html/language-comment/__snapshots__/jsfmt.spec.js.snap
 create mode 100644 tests/js/multiparser-html/language-comment/jsfmt.spec.js
 create mode 100644 tests/js/multiparser-html/language-comment/not-language-comment.js

diff --git a/changelog_unreleased/javascript/9743.md b/changelog_unreleased/javascript/9743.md
new file mode 100644
index 000000000..376d20e92
--- /dev/null
+++ b/changelog_unreleased/javascript/9743.md
@@ -0,0 +1,19 @@
+#### Fix inconsistent language comment detection (#9743 by @fisker)
+
+<!-- prettier-ignore -->
+```jsx
+// Input
+foo /* HTML */ = `<DIV>
+</DIV>`;
+
+// Prettier stable (--parser=babel)
+foo /* HTML */ = `<div></div>`;
+
+// Prettier stable (--parser=meriyah)
+foo /* HTML */ = `<DIV>
+</DIV>`;
+
+// Prettier master (All JavaScript parsers)
+foo /* HTML */ = `<DIV>
+</DIV>`;
+```
diff --git a/src/language-js/comments.js b/src/language-js/comments.js
index af0866175..91cd34ffa 100644
--- a/src/language-js/comments.js
+++ b/src/language-js/comments.js
@@ -19,8 +19,6 @@ const {
   hasFlowShorthandAnnotationComment,
   hasFlowAnnotationComment,
   hasIgnoreComment,
-  hasComment,
-  CommentCheckFlags,
 } = require("./utils");
 const { locStart, locEnd } = require("./loc");
 
@@ -866,18 +864,6 @@ function handleTSMappedTypeComments({
   return false;
 }
 
-/**
- * @param {Node} node
- * @param {(comment: Comment) => boolean} fn
- * @returns boolean
- */
-function hasLeadingComment(node, fn = () => true) {
-  if (node.leadingComments) {
-    return node.leadingComments.some(fn);
-  }
-  return hasComment(node, CommentCheckFlags.Leading, fn);
-}
-
 /**
  * @param {Node} node
  * @returns {boolean}
@@ -994,7 +980,6 @@ module.exports = {
   handleOwnLineComment,
   handleEndOfLineComment,
   handleRemainingComment,
-  hasLeadingComment,
   isTypeCastComment,
   getGapRegex,
   getCommentChildNodes,
diff --git a/src/language-js/embed.js b/src/language-js/embed.js
index 7c7ee3eb9..3058e7868 100644
--- a/src/language-js/embed.js
+++ b/src/language-js/embed.js
@@ -1,7 +1,6 @@
 "use strict";
 
-const { isBlockComment } = require("./utils");
-const { hasLeadingComment } = require("./comments");
+const { hasComment, CommentCheckFlags } = require("./utils");
 const formatMarkdown = require("./embed/markdown");
 const formatCss = require("./embed/css");
 const formatGraphql = require("./embed/graphql");
@@ -267,10 +266,10 @@ function hasLanguageComment(node, languageName) {
   // we will not trim the comment value and we will expect exactly one space on
   // either side of the GraphQL string
   // Also see ./clean.js
-  return hasLeadingComment(
+  return hasComment(
     node,
-    (comment) =>
-      isBlockComment(comment) && comment.value === ` ${languageName} `
+    CommentCheckFlags.Block | CommentCheckFlags.Leading,
+    ({ value }) => value === ` ${languageName} `
   );
 }
 
diff --git a/tests/js/multiparser-html/language-comment/__snapshots__/jsfmt.spec.js.snap b/tests/js/multiparser-html/language-comment/__snapshots__/jsfmt.spec.js.snap
new file mode 100644
index 000000000..025e71c48
--- /dev/null
+++ b/tests/js/multiparser-html/language-comment/__snapshots__/jsfmt.spec.js.snap
@@ -0,0 +1,19 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`not-language-comment.js format 1`] = `
+====================================options=====================================
+parsers: ["babel", "flow", "typescript"]
+printWidth: 80
+                                                                                | printWidth
+=====================================input======================================
+const html /* HTML */ = \`<DIV>
+
+</DIV>\`;
+
+=====================================output=====================================
+const html /* HTML */ = \`<DIV>
+
+</DIV>\`;
+
+================================================================================
+`;
diff --git a/tests/js/multiparser-html/language-comment/jsfmt.spec.js b/tests/js/multiparser-html/language-comment/jsfmt.spec.js
new file mode 100644
index 000000000..eb85eda6b
--- /dev/null
+++ b/tests/js/multiparser-html/language-comment/jsfmt.spec.js
@@ -0,0 +1 @@
+run_spec(__dirname, ["babel", "flow", "typescript"]);
diff --git a/tests/js/multiparser-html/language-comment/not-language-comment.js b/tests/js/multiparser-html/language-comment/not-language-comment.js
new file mode 100644
index 000000000..ee5517b7b
--- /dev/null
+++ b/tests/js/multiparser-html/language-comment/not-language-comment.js
@@ -0,0 +1,3 @@
+const html /* HTML */ = `<DIV>
+
+</DIV>`;