Fix out of bounds panic when tsconfig "files" contains duplicates

[andrewbranch]

Discovered this while investigating something else

[andrewbranch]

Wait this isn't quite right

[andrewbranch]

Yes it is. Test modification proves it

[Copilot]

Pull Request Overview

This PR fixes an out-of-bounds panic when the tsconfig "files" array contains duplicate entries. The solution tracks the actual number of literal files separately from the total file count, preventing incorrect array slicing when duplicates cause the literal file count to be smaller than expected.

Key changes:

• Modified getFileNamesFromConfigSpecs to return both file names and literal file count
• Added literalFileNamesLen field to track the actual number of unique literal files
• Updated LiteralFileNames() method to use the tracked count instead of the original file spec length

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
internal/tsoptions/tsconfigparsing.go	Modified file name resolution functions to return literal file count and updated parsing logic to track this count
internal/tsoptions/parsedcommandline.go	Added literalFileNamesLen field and updated LiteralFileNames() method to use the tracked count instead of file spec length
internal/tsoptions/parsedcommandline_test.go	Added test case to verify duplicate files in tsconfig are handled correctly

[sheetalkamat]

I think fix should be at program and hence duplicate of #1549

The main blocking here is file casing and module resolutions that happen and discussion for that fix here #1535

[andrewbranch]

I don’t think this is a duplicate; I wasn’t targeting a fix to programs at all. The test case added here, using only config file parsing and its methods, panics without the fix. LiteralFileNames is used by the LSP infrastructure without a program being involved.

[sheetalkamat]

I don’t think this is a duplicate; I wasn’t targeting a fix to programs at all. The test case added here, using only config file parsing and its methods, panics without the fix. LiteralFileNames is used by the LSP infrastructure without a program being involved.

Oh i see.. I forgot that we use Literal file names stuff for watching and matching..