Fix comments on class methods with decorators (#16891)

changelog_unreleased/typescript/16891.md

@@ -0,0 +1,40 @@
+#### Fix comments print on class methods with decorators (#16891 by @fisker)
+
+<!-- prettier-ignore -->
+```jsx
+// Input
+class A {
+  @decorator
+  /** 
+   * The method description
+   *
+  */
+  async method(foo: Foo, bar: Bar) {
+    console.log(foo);
+  }
+}
+
+// Prettier stable
+class A {
+  @decorator
+  async /**
+   * The method description
+   *
+   */
+  method(foo: Foo, bar: Bar) {
+    console.log(foo);
+  }
+}
+
+// Prettier main
+class A {
+  @decorator
+  /**
+   * The method description
+   *
+   */
+  async method(foo: Foo, bar: Bar) {
+    console.log(foo);
+  }
+}
+```

src/language-js/comments/handle-comments.js

@@ -543,7 +543,7 @@ function handleMethodNameComments({
   if (
     precedingNode?.type === "Decorator" &&
     propertyLikeNodeTypes.has(enclosingNode?.type) &&
-    isLineComment(comment)
+    (isLineComment(comment) || comment.placement === "ownLine")
   ) {
     addTrailingComment(precedingNode, comment);
     return true;

tests/format/typescript/comments/16889.ts

@@ -0,0 +1,71 @@
+class A {
+  @decorator
+  /**
+   * The method description
+   *
+  */
+  async method() {
+  }
+
+  @decorator/**
+   * The method description
+   *
+  */
+  async method() {
+  }
+
+  @decorator/**
+   * The method description
+   *
+  */ async method() {
+  }
+
+  @decorator
+  async /* comment */ method() {
+  }
+
+  @decorator /* comment */ async method() {
+  }
+
+  @decorator
+  // line comment
+  async method() {
+  }
+
+  @decorator // line comment
+  async method() {
+  }
+
+
+  @decorator
+   /* comment */
+  public async method() {
+  }
+
+  @decorator
+   /* comment */
+  static async method() {
+  }
+
+  @decorator
+   /* comment */
+  protected async method() {
+  }
+
+  @decorator
+   /* comment */
+  protected async method() {
+  }
+
+  @decorator
+   /* comment */
+  * method() {}
+
+  @decorator
+  * /* comment */ method() {}
+
+   /* comment */
+  abstract method():void;
+
+}
+

tests/format/typescript/comments/__snapshots__/format.test.js.snap

@@ -248,6 +248,147 @@ class Foo {
 ================================================================================
 `;
 
+exports[`16889.ts format 1`] = `
+====================================options=====================================
+parsers: ["typescript"]
+printWidth: 80
+                                                                                | printWidth
+=====================================input======================================
+class A {
+  @decorator
+  /**
+   * The method description
+   *
+  */
+  async method() {
+  }
+
+  @decorator/**
+   * The method description
+   *
+  */
+  async method() {
+  }
+
+  @decorator/**
+   * The method description
+   *
+  */ async method() {
+  }
+
+  @decorator
+  async /* comment */ method() {
+  }
+
+  @decorator /* comment */ async method() {
+  }
+
+  @decorator
+  // line comment
+  async method() {
+  }
+
+  @decorator // line comment
+  async method() {
+  }
+
+
+  @decorator
+   /* comment */
+  public async method() {
+  }
+
+  @decorator
+   /* comment */
+  static async method() {
+  }
+
+  @decorator
+   /* comment */
+  protected async method() {
+  }
+
+  @decorator
+   /* comment */
+  protected async method() {
+  }
+
+  @decorator
+   /* comment */
+  * method() {}
+
+  @decorator
+  * /* comment */ method() {}
+
+   /* comment */
+  abstract method():void;
+
+}
+
+
+=====================================output=====================================
+class A {
+  @decorator
+  /**
+   * The method description
+   *
+   */
+  async method() {}
+
+  @decorator /**
+   * The method description
+   *
+   */
+  async method() {}
+
+  @decorator /**
+   * The method description
+   *
+   */
+  async method() {}
+
+  @decorator
+  async /* comment */ method() {}
+
+  @decorator /* comment */ async method() {}
+
+  @decorator
+  // line comment
+  async method() {}
+
+  @decorator // line comment
+  async method() {}
+
+  @decorator
+  /* comment */
+  public async method() {}
+
+  @decorator
+  /* comment */
+  static async method() {}
+
+  @decorator
+  /* comment */
+  protected async method() {}
+
+  @decorator
+  /* comment */
+  protected async method() {}
+
+  @decorator
+  /* comment */
+  *method() {}
+
+  @decorator
+  */* comment */ method() {}
+
+  /* comment */
+  abstract method(): void;
+}
+
+================================================================================
+`;
+
 exports[`abstract_class.ts format 1`] = `
 ====================================options=====================================
 parsers: ["typescript"]