From 66181dbe3705ac0430a549191ddd1b18dd2d8cbf Mon Sep 17 00:00:00 2001
From: Jason <jason.daurus@gmail.com>
Date: Wed, 21 Apr 2021 21:57:57 +0800
Subject: [PATCH] fix: don't deduplicate comments with same start index
 (#13169)

---
 packages/babel-generator/src/printer.ts |  6 ------
 packages/babel-generator/test/index.js  | 14 ++++++++++++++
 2 files changed, 14 insertions(+), 6 deletions(-)

diff --git a/packages/babel-generator/src/printer.ts b/packages/babel-generator/src/printer.ts
index 176870cc2a..4c4201ac69 100644
--- 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
index e56cd9754e..f46d4dd4a3 100644
--- 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 () {