fix: Props are lost when the template replaces the node (#15286)

babel · Jul 25, 2024 · b540ab3 · b540ab3
1 parent dcfa42b
commit b540ab3
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Showing 3 changed files with 73 additions and 3 deletions.
diff --git a/packages/babel-template/src/populate.ts b/packages/babel-template/src/populate.ts
@@ -121,10 +121,26 @@ function applyReplacement(
     }
   }
 
+  function set(parent: any, key: any, value: any) {
+    const node = parent[key] as t.Node;
+    parent[key] = value;
+    if (node.type === "Identifier") {
+      if (node.typeAnnotation) {
+        value.typeAnnotation = node.typeAnnotation;
+      }
+      if (node.optional) {
+        value.optional = node.optional;
+      }
+      if (node.decorators) {
+        value.decorators = node.decorators;
+      }
+    }
+  }
+
   if (index === undefined) {
     validate(parent, key, replacement);
 
-    (parent as any)[key] = replacement;
+    set(parent, key, replacement);
   } else {
     const items: Array<t.Node> = (parent as any)[key].slice();
 
@@ -134,10 +150,10 @@ function applyReplacement(
       } else if (Array.isArray(replacement)) {
         items.splice(index, 1, ...replacement);
       } else {
-        items[index] = replacement;
+        set(items, index, replacement);
       }
     } else {
-      items[index] = replacement;
+      set(items, index, replacement);
     }
 
     validate(parent, key, items);

diff --git a/packages/babel-template/test/index.js b/packages/babel-template/test/index.js
@@ -473,5 +473,53 @@ describe("@babel/template", function () {
       });
       expect(generator(output).code).toMatchInlineSnapshot(`"let x = 7;"`);
     });
+
+    it("should keep node props", () => {
+      const outputs = [
+        template({ plugins: ["typescript"] }).ast`
+          const ${t.identifier("greeting")}: string = 'Hello';
+        `,
+        template({ plugins: ["typescript"] }).ast`
+          var ${t.objectPattern([])}: string = x;
+        `,
+        template({ plugins: ["decorators-legacy"] }).ast`
+          class X {
+            f(@dec ${t.identifier("x")}) {}
+          }
+        `,
+        template({ plugins: ["typescript"] }).ast`
+          function f(${t.identifier("x")}?) {}
+        `,
+        template({ plugins: ["typescript"] }).ast`
+          function f(${Object.assign(t.identifier("x"), { optional: true })}: string) {}
+        `,
+        template({ plugins: ["decorators-legacy"] }).ast`
+          class X {
+            f(@dec ${Object.assign(t.identifier("x"), { optional: true })}) {}
+          }
+        `,
+        template({ plugins: ["typescript"] }).ast`
+          function f(${Object.assign(t.identifier("x"), { typeAnnotation: t.tsTypeAnnotation(t.tsStringKeyword()) })}: number) {}
+        `,
+      ];
+
+      expect(outputs.map(ast => generator(ast).code)).toMatchInlineSnapshot(`
+        Array [
+          "const greeting: string = 'Hello';",
+          "var {}: string = x;",
+          "class X {
+          f(@dec
+          x) {}
+        }",
+          "function f(x?) {}",
+          "function f(x?: string) {}",
+          "class X {
+          f(@dec
+          x?) {}
+        }",
+          "function f(x: number) {}",
+        ]
+      `);
+    });
   });
 });
diff --git a/packages/babel-types/src/clone/cloneNode.ts b/packages/babel-types/src/clone/cloneNode.ts
@@ -76,6 +76,12 @@ function cloneNodeInternal<T extends t.Node>(
           )
         : node.typeAnnotation;
     }
+
+    if (hasOwn(node, "decorators")) {
+      newNode.decorators = deep
+        ? cloneIfNodeOrArray(node.decorators, true, withoutLoc, commentsCache)
+        : node.decorators;
+    }
   } else if (!hasOwn(NODE_FIELDS, type)) {
     throw new Error(`Unknown node type: "${type}"`);
   } else {