Fix missing JSDoc comments on destructured interface properties

[Copilot]

• Understand the issue: Destructured interface members lack inherited JSDoc comments
• Create a fourslash test to reproduce the issue
• Verify the test fails as expected
• Research the TypeScript reference implementation
• Identify the fix needed: Add special handling for binding elements in hover.go
• Implement the fix to handle binding elements
• Run tests to verify the fix works
• Test renamed destructuring edge case
• Run linters and build
• Run broader test suite
• Update baselines
• Address code review feedback
• Final verification with CodeQL
• Simplify code using IsUnion() and Types() methods

Summary

Fixed the issue where destructured interface members were not showing inherited JSDoc comments when hovering.

Changes Made:

1. Modified getDocumentationFromDeclaration in internal/ls/hover.go to detect binding elements (destructured variables) and retrieve documentation from the corresponding property in the source type
2. Added a helper function findPropertyInType to handle union types properly (simplified using IsUnion() and Types() methods)
3. Updated function signature to pass symbol and location for proper context
4. Added comprehensive tests for both basic and renamed destructuring
5. Updated 4 baseline tests that now correctly show JSDoc comments

Testing:

• All existing tests pass
• New tests added for destructuring with JSDoc
• Baseline tests updated to reflect correct behavior
• No security vulnerabilities detected by CodeQL

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Destructured interface members lack inherited JSDoc comments</issue_title>
<issue_description>### Extension Version

0.20251203.1

VS Code Version

1.106.3

Operating system Version

Ubuntu x86-64, running via Windows 11 inside WSL

Steps to reproduce

1. Copy this MRE:

   interface FooBar {
       /** foo comment */
       foo: number;
       /** bar comment */
       bar: string;
       /** baz comment */
       baz: string;
   }
   
   declare const fubar: FooBar;
   
   const {foo, bar, baz} = fubar;

2. hover over properties
3. no comments

Issue

Should have hovers, as is present in normal typescript</issue_description>

<agent_instructions>Make a fourslash test in ./internal/fourslash/tests first; see internal/fourslash/tests/hoverAliasInImportedFile_test.go for an example.

Remember that you have a reference hover implementation in the submodule to cross compare.

You can use print debugging with go test -v as well.</agent_instructions>

Comments on the Issue (you are @copilot in this section)

• Fixes Destructured interface members lack inherited JSDoc comments #2194

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[Copilot]

Pull request overview

This PR fixes an issue where destructured interface members were not showing their inherited JSDoc comments when hovering over them in the editor. The fix adds special handling for binding elements (variables created from destructuring) in the hover implementation to retrieve documentation from the corresponding property in the source type.

Key Changes

• Modified getDocumentationFromDeclaration to detect binding elements and retrieve documentation from the interface property
• Added helper function findPropertyInType to handle union types when searching for properties
• Updated function signature to pass symbol and location context
• Added comprehensive tests for both basic and renamed destructuring scenarios

Reviewed changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated no comments.

File	Description
internal/ls/hover.go	Added binding element detection logic and helper function to find property documentation in source types, updated function signature
internal/ls/signaturehelp.go	Updated call to getDocumentationFromDeclaration with new signature
internal/fourslash/tests/destructuredInterfaceJSDoc_test.go	Added new tests for destructured interface JSDoc comments, including renamed properties
testdata/baselines/reference/fourslash/quickInfo/*.baseline	Updated 4 baseline tests to correctly show JSDoc comments for destructured properties

[jakebailey]

I think this is not unreasonable; it is the same code, but things are shifted around in the Go version.