Handle undefined location.parent when getting completionEntryDetails

[MariaSolOs]

Fixes #54106

[MariaSolOs]

Tests are pending because I don't know how to test completionEntryDetails. verify.completions seems to only check completionInfo, and I cannot use the resulting andApplyCodeAction because the entry I want to test doesn't have a description or source (which are needed in the parameter options).

[jakebailey]

Where is this location coming from? All source files should be bound and have parents, so is this location the SourceFile itself?

[MariaSolOs]

Where is this location coming from? All source files should be bound and have parents, so is this location the SourceFile itself?

Correct. So with the example from the bug:

/**/
type lolol = any;
declare const lolol: any;

When explicitly requesting completions in /**/, location will be the source file itself, which causes the error in the line I'm changing.

[MariaSolOs]

@jakebailey @DanielRosenwasser @andrewbranch any hints on how I can test this with fourslash?

[jakebailey]

Are the details in https://github.com/microsoft/TypeScript/blob/main/tests/cases/fourslash/completionsObjectLiteralMethod2.ts what you're trying to get at?

[MariaSolOs]

Are the details in https://github.com/microsoft/TypeScript/blob/main/tests/cases/fourslash/completionsObjectLiteralMethod2.ts what you're trying to get at?

Hmm no this isn't helping me here. The completion entry remains the same with and without my change, like I need to simulate selecting the actual completion to trigger the failure.

[MariaSolOs]

Okay I was able to test this with verify.baselineCompletions(). You were right @iisaduan!