microsoft / microsoft/TypeScript
ES `ClassDecoratorContext.name` has incorrect value with static `name`
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Description
### 🔎 Search Terms
ClassDecoratorContext static name
### 🕗 Version & Regression Information
5.0.4-5.9.3
### ⏯ Playground Link
https://tsplay.dev/N7vAow
### 💻 Code
```ts
const decorate = (_: unknown, ctx: ClassDecoratorContext) => {
console.log('decorate(%o)', ctx.name);
};
@decorate
class A {
static get name() {
return 2434;
}
}
```
### 🙁 Actual behavior
`ctx.name` is `2434` (from `A.name`)
### 🙂 Expected behavior
`ctx.name` is `'A'` (actual class name)
### Additional information about the issue
The wrong value comes from the context initializer in the emitted code:
```ts
__esDecorate(
null,
(_classDescriptor = { value: _classThis }),
_classDecorators,
{ kind: 'class', name: _classThis.name, metadata: _metadata },
null,
_classExtraInitializers,
);
```
The context `name` is initialized with `_classThis.name` (which triggers the getter) instead of the actual class name value (literal `"A"` in this case).
## Possible Fix
Currently, the `_classThis.name` fragment comes from `const classNameReference` in `transformClassLike` in `transformers/esDecorators.ts`:
```ts
const classNameReference = factory.createPropertyAccessExpression(renamedClassThis, "name");
```
It should be adjusted to get an actual class name (either literal or computed), possibly like this:
```ts
const classNameReference = node.name ? factory.createStringLiteralFromNode(node.name) :
node.emitNode?.assignedName ?? factory.createStringLiteral("")
```
Contributor guide
Research direction
Start in transformers/esDecorators.ts at transformClassLike and inspect how classNameReference is built for the class decorator context. Reproduce the issue with the linked playground, then verify that a class with a static name getter supplies its actual declared name, such as "A", to ctx.name rather than the getter result.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- typescript
- Domain
- compilers
- Issue type
- Bug
- Difficulty
- 3/5
- Estimated time
- 1-2 days
- Activity status
- Stale
- Clarity
- Clearly specified
- Newbie friendliness
- 55/100