Question about rust crate biome_js_semantic

[fireairforce]

The source code is: https://github.com/biomejs/biome/blob/main/crates/biome_js_semantic/src/events.rs#L555

I would like to ask why the semantics of biome will filter out the kind TS_QUALIFIED_NAME when analyzing the reference of binding. I have such a scenario of mutation.rename_node_declaration:

namespace A {
  export type B = Number;
  export const a = 1;
}

let a: A.B = A.a;

I want to renaming the namespace binding A to A_1 , for the reason references filter out TS_QUALIFIED_NAME, the renaming output will be:

namespace A_1 {
  export type B = Number;
  export const a = 1;
}

let a: A.B = A_1.a;

the A.B will not change here.

I'm not sure why biome does this. Is there any background reason I can understand?

looking forward to your reply~

[Conaclos]

I would like to ask why the semantics of biome will filter out the kind TS_QUALIFIED_NAME when analyzing the reference of binding.

Because TsQualifiedName may recursively include multiple qualification such as A.B.C.D.

The code skips TS_QUALIFIED_NAME and should end with a TS_REFERENCE_TYPE node.

Here A.B in let a: A.B is a TsReferenceType that includes a TsQualifiedName. A is a JsReferenceIdentifier. You can use the Playground to visualize the AST.

I think the semantic model correctly binds this reference to the namespace declaration.
The issue is certainly coming from the rename facility.

[fireairforce]

If I want to fix here, may be i can deal the A.B(A) into BindingName::Value ?

[Conaclos]

Indeed, you are right.

Unfortunately I don't see an easy fix there.
Because this code is useful in at least three cases:

• to skip import type qualifier. For example:

  type T = import("mod").A.B.C;

  Here A.B.C is a TS_QULIFIED_NAME.
• to correctly handle typeof. For example:

  import type { A } from "mod"
  type T = typeof A.B.C;

• to handle references to a namespace imported as a type:

  import type { A } from "./ns.js"
  type T = A.B;

Fixing the issue could require to use the sane trick that BindingName::Typeof by delaying the resolution to pop_scope.

[Conaclos]

Another possibility could be to add a special case in pop_scope: When a TsRefrenceType is unresolved and is a qualified name and a namespace declaration is in the scope, then bind the ref to the declaration.

[fireairforce]

I add a draft pr for this change: #2092, maybe you can take a look when you feel free, thank you~