fix: don't deduplicate comments with same start index (#13169)

babel · Apr 21, 2021 · 66181db · 66181db
1 parent adb5ada
commit 66181db
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Showing 2 changed files with 14 additions and 6 deletions.
diff --git a/packages/babel-generator/src/printer.ts b/packages/babel-generator/src/printer.ts
@@ -44,7 +44,6 @@ class Printer {
   _printStack: Array<t.Node> = [];
   _indent: number = 0;
   _insideAux: boolean = false;
-  _printedCommentStarts: any = {};
   _parenPushNewlineState: any = null;
   _noLineTerminator: boolean = false;
   _printAuxAfterOnNextUserNode: boolean = false;
@@ -598,11 +597,6 @@ class Printer {
     if (this._printedComments.has(comment)) return;
     this._printedComments.add(comment);
 
-    if (comment.start != null) {
-      if (this._printedCommentStarts[comment.start]) return;
-      this._printedCommentStarts[comment.start] = true;
-    }
-
     const isBlockComment = comment.type === "CommentBlock";
 
     // Add a newline before and after a block comment, unless explicitly

diff --git a/packages/babel-generator/test/index.js b/packages/babel-generator/test/index.js
@@ -348,6 +348,20 @@ describe("generation", function () {
     const output = generate(type).code;
     expect(output).toBe("(infer T)[]");
   });
+
+  it("should not deduplicate comments with same start index", () => {
+    const code1 = "/*#__PURE__*/ a();";
+    const code2 = "/*#__PURE__*/ b();";
+
+    const ast1 = parse(code1).program;
+    const ast2 = parse(code2).program;
+
+    const ast = t.program([...ast1.body, ...ast2.body]);
+
+    expect(generate(ast).code).toBe(
+      "/*#__PURE__*/\na();\n\n/*#__PURE__*/\nb();",
+    );
+  });
 });
 
 describe("programmatic generation", function () {