From ebc995158bbde89f0f8e5ad5f1dbcca5e06eb03d Mon Sep 17 00:00:00 2001
From: fisker Cheung <lionkay@gmail.com>
Date: Thu, 25 Jun 2026 10:10:01 +0800
Subject: [PATCH] Add more tests for "assignment like" node (#19447)

---
 .../attach/handle-if-statement-comments.js    |  2 +-
 src/language-js/comments/attach/union-type.js |  6 +-
 src/language-js/comments/attach/utilities.js  | 18 ++++-
 .../__snapshots__/format.test.js.snap         |  4 +-
 .../__snapshots__/format.test.js.snap         | 65 +++++++++++++++++++
 .../js/comments/assignment/format.test.js     |  1 +
 .../assignment/variable-declarator.js         | 27 ++++++++
 ...e_declarator.js => variable-declarator.js} |  0
 8 files changed, 113 insertions(+), 10 deletions(-)
 create mode 100644 tests/format/js/comments/assignment/__snapshots__/format.test.js.snap
 create mode 100644 tests/format/js/comments/assignment/format.test.js
 create mode 100644 tests/format/js/comments/assignment/variable-declarator.js
 rename tests/format/js/comments/{variable_declarator.js => variable-declarator.js} (100%)

diff --git a/src/language-js/comments/attach/handle-if-statement-comments.js b/src/language-js/comments/attach/handle-if-statement-comments.js
index 74379b456..9bb0a7a22 100644
--- a/src/language-js/comments/attach/handle-if-statement-comments.js
+++ b/src/language-js/comments/attach/handle-if-statement-comments.js
@@ -100,7 +100,7 @@ function handleCommentsBetween({
   // - treat as a dangling comment otherwise
   if (
     !isConsequentBlockStatement &&
-    isSingleLineComment &&
+    isSingleLineComment(comment, text) &&
     // Comment and `precedingNode` are on same line
     !hasNewlineInRange(text, locEnd(precedingNode), locStart(comment))
   ) {
diff --git a/src/language-js/comments/attach/union-type.js b/src/language-js/comments/attach/union-type.js
index 6bc654ea3..24f47512a 100644
--- a/src/language-js/comments/attach/union-type.js
+++ b/src/language-js/comments/attach/union-type.js
@@ -1,16 +1,14 @@
 import { addLeadingComment } from "../../../main/comments/utilities.js";
 import { locEnd, locStart } from "../../location/index.js";
-import { isBlockComment } from "../../utilities/comment-types.js";
 import { isPrettierIgnoreComment } from "../../utilities/is-prettier-ignore-comment.js";
 import { isUnionType } from "../../utilities/node-types.js";
 import { stripComments } from "../../utilities/strip-comments.js";
-import { isSingleLineComment } from "../attach/utilities.js";
+import { isSingleLineBlockComment } from "../attach/utilities.js";
 
 function shouldAttachToUnionTypeFirstElement(node, { comment, text, options }) {
   if (
     isUnionType(node) &&
-    isBlockComment(comment) &&
-    isSingleLineComment(comment, text) &&
+    isSingleLineBlockComment(comment, text) &&
     !isPrettierIgnoreComment(comment)
   ) {
     const text = stripComments(options);
diff --git a/src/language-js/comments/attach/utilities.js b/src/language-js/comments/attach/utilities.js
index 826520f6c..0013d8417 100644
--- a/src/language-js/comments/attach/utilities.js
+++ b/src/language-js/comments/attach/utilities.js
@@ -4,7 +4,10 @@ import {
 } from "../../../main/comments/utilities.js";
 import hasNewlineInRange from "../../../utilities/has-newline-in-range.js";
 import { locEnd, locStart } from "../../location/index.js";
-import { isLineComment } from "../../utilities/comment-types.js";
+import {
+  isBlockComment,
+  isLineComment,
+} from "../../utilities/comment-types.js";
 
 /**
 @import {Node, Comment, NodeMap} from "../../types/estree.js";
@@ -15,10 +18,18 @@ import { isLineComment } from "../../utilities/comment-types.js";
 @param {string} text
 @returns {boolean}
 */
-const isSingleLineComment = (comment, text) =>
-  isLineComment(comment) ||
+const isSingleLineBlockComment = (comment, text) =>
+  isBlockComment(comment) &&
   !hasNewlineInRange(text, locStart(comment), locEnd(comment));
 
+/**
+@param {Comment} comment
+@param {string} text
+@returns {boolean}
+*/
+const isSingleLineComment = (comment, text) =>
+  isLineComment(comment) || isSingleLineBlockComment(comment, text);
+
 /**
  * @param {Node} node
  * @returns {void}
@@ -50,5 +61,6 @@ function addBlockStatementFirstComment(node, comment) {
 export {
   addBlockOrNotComment,
   addBlockStatementFirstComment,
+  isSingleLineBlockComment,
   isSingleLineComment,
 };
diff --git a/tests/format/js/comments/__snapshots__/format.test.js.snap b/tests/format/js/comments/__snapshots__/format.test.js.snap
index b1c6bb994..67004e2c4 100644
--- a/tests/format/js/comments/__snapshots__/format.test.js.snap
+++ b/tests/format/js/comments/__snapshots__/format.test.js.snap
@@ -7216,7 +7216,7 @@ try {
 ================================================================================
 `;
 
-exports[`variable_declarator.js - {"semi":false} format 1`] = `
+exports[`variable-declarator.js - {"semi":false} format 1`] = `
 ====================================options=====================================
 parsers: ["babel", "flow", "typescript"]
 semi: false
@@ -7366,7 +7366,7 @@ const foo3 = 123
 ================================================================================
 `;
 
-exports[`variable_declarator.js format 1`] = `
+exports[`variable-declarator.js format 1`] = `
 ====================================options=====================================
 parsers: ["babel", "flow", "typescript"]
                                                       printWidth: 80 (default) |
diff --git a/tests/format/js/comments/assignment/__snapshots__/format.test.js.snap b/tests/format/js/comments/assignment/__snapshots__/format.test.js.snap
new file mode 100644
index 000000000..7786f4462
--- /dev/null
+++ b/tests/format/js/comments/assignment/__snapshots__/format.test.js.snap
@@ -0,0 +1,65 @@
+// Jest Snapshot v1, https://jestjs.io/docs/snapshot-testing
+
+exports[`variable-declarator.js format 1`] = `
+====================================options=====================================
+parsers: ["babel", "flow", "typescript"]
+                                                      printWidth: 80 (default) |
+=====================================input======================================
+let a1 // commment
+ = 1;
+let a12
+// commment
+ = 1;
+let a2 /* commment */
+ = 1;
+let a22
+/* commment */
+ = 1;
+let a3 /*
+commment */
+ = 1;
+let a32
+/*
+commment */
+ = 1;
+let a4 = // comment
+1;
+let a42 =
+// comment
+1;
+let a5 = /* commment */
+1;
+let a52 =
+/* commment */
+1;
+
+=====================================output=====================================
+let a1 = 1; // commment
+let a12 =
+  // commment
+  1;
+let a2 = /* commment */ 1;
+let a22 =
+  /* commment */
+  1;
+let a3 =
+  /*
+commment */
+  1;
+let a32 =
+  /*
+commment */
+  1;
+let a4 =
+  // comment
+  1;
+let a42 =
+  // comment
+  1;
+let a5 = /* commment */ 1;
+let a52 =
+  /* commment */
+  1;
+
+================================================================================
+`;
diff --git a/tests/format/js/comments/assignment/format.test.js b/tests/format/js/comments/assignment/format.test.js
new file mode 100644
index 000000000..67c251cce
--- /dev/null
+++ b/tests/format/js/comments/assignment/format.test.js
@@ -0,0 +1 @@
+runFormatTest(import.meta, ["babel", "flow", "typescript"]);
diff --git a/tests/format/js/comments/assignment/variable-declarator.js b/tests/format/js/comments/assignment/variable-declarator.js
new file mode 100644
index 000000000..d390c830e
--- /dev/null
+++ b/tests/format/js/comments/assignment/variable-declarator.js
@@ -0,0 +1,27 @@
+let a1 // commment
+ = 1;
+let a12
+// commment
+ = 1;
+let a2 /* commment */
+ = 1;
+let a22
+/* commment */
+ = 1;
+let a3 /*
+commment */
+ = 1;
+let a32
+/*
+commment */
+ = 1;
+let a4 = // comment
+1;
+let a42 =
+// comment
+1;
+let a5 = /* commment */
+1;
+let a52 =
+/* commment */
+1;
diff --git a/tests/format/js/comments/variable_declarator.js b/tests/format/js/comments/variable-declarator.js
similarity index 100%
rename from tests/format/js/comments/variable_declarator.js
rename to tests/format/js/comments/variable-declarator.js