fix(migrations): class content being deleted in some edge cases (#58959)

crisbeto · pkozlowski-opensource · commit e31e52e1771e · 2024-12-02T08:56:20.000+01:00
Fixes that the inject migration was deleting the class' content if a property exists after the constructor that is being rewritten. PR Close #58959
diff --git a/packages/core/schematics/ng-generate/inject-migration/migration.ts b/packages/core/schematics/ng-generate/inject-migration/migration.ts
@@ -259,7 +259,15 @@ function migrateClass(
 
   if (prependToClass.length > 0) {
     if (removedMembers.size === node.members.length) {
-      tracker.insertText(sourceFile, constructor.getEnd() + 1, `${prependToClass.join('\n')}\n`);
+      tracker.insertText(
+        sourceFile,
+        // If all members were deleted, insert after the last one.
+        // This allows us to preserve the indentation.
+        node.members.length > 0
+          ? node.members[node.members.length - 1].getEnd() + 1
+          : node.getEnd() - 1,
+        `${prependToClass.join('\n')}\n`,
+      );
     } else {
       // Insert the new properties after the first member that hasn't been deleted.
       tracker.insertText(
diff --git a/packages/core/schematics/test/inject_migration_spec.ts b/packages/core/schematics/test/inject_migration_spec.ts
@@ -2387,5 +2387,41 @@ describe('inject migration', () => {
         `}`,
       ]);
     });
+
+    it('should handle properties being migrated both before and after the constructor', async () => {
+      writeFile(
+        '/dir.ts',
+        [
+          `import { Directive } from '@angular/core';`,
+          `import { Foo } from 'foo';`,
+          ``,
+          `@Directive()`,
+          `class MyDir {`,
+          `  private beforeConstructor: number;`,
+          ``,
+          `  constructor(private foo: Foo) {`,
+          `    this.beforeConstructor = this.foo.getValue();`,
+          `    this.afterConstructor = this.beforeConstructor + 1;`,
+          `  }`,
+          ``,
+          `  private afterConstructor: number;`,
+          `}`,
+        ].join('\n'),
+      );
+
+      await runInternalMigration();
+
+      expect(tree.readContent('/dir.ts').split('\n')).toEqual([
+        `import { Directive, inject } from '@angular/core';`,
+        `import { Foo } from 'foo';`,
+        ``,
+        `@Directive()`,
+        `class MyDir {`,
+        `  private foo = inject(Foo);`,
+        `  private beforeConstructor: number = this.foo.getValue();`,
+        `  private afterConstructor: number = this.beforeConstructor + 1;`,
+        `}`,
+      ]);
+    });
   });
 });
