LSP: newly created file is assigned to the wrong project when the project path contains '[' / '{' (or include differs only by case) #64987

🔎 Search Terms

PossiblyMatchesFileName, WildcardDirectoryGlobs, glob brackets, glob escape, square brackets path, curly braces directory, new file wrong project, newly created file not included in project, include case insensitive

🕗 Version & Regression Information

• I was unable to test this on prior versions because I only built and tested main at commit 4163ca1 (tsgo --version: Version 7.1.0-dev).
• Related but different: No autocomplete for local symbols and some global types when creating a new file typescript-go#3733 (fixed by Fix wildcard directories being dropped for "./"-prefixed includes with dot-directory excludes typescript-go#4529) had the same symptom from a different cause. That fix is present at this commit, and this bug still reproduces.

⏯ Playground Link

N/A: this needs files on disk in a folder with [ in its name, two nested tsconfigs, and a file-created event, which the Playground can't reproduce.

💻 Code

Layout (note the [ws] folder in the path):

/tmp/x/[ws]/monorepo/tsconfig.json
{"compilerOptions":{"target":"ES2015","lib":["ES2015"],"noEmit":true,"types":[]},"include":["apps"]}

/tmp/x/[ws]/monorepo/apps/web/tsconfig.json
{"compilerOptions":{"target":"ESNext","lib":["ESNext"],"noEmit":true,"types":[]},"include":["app"]}

/tmp/x/[ws]/monorepo/apps/web/app/existing.ts

export const a = [1, 2].findLast(x => x > 0);

Steps:

1. Start tsgo --lsp --stdio with the workspace at /tmp/x/[ws]/monorepo.
2. Open apps/web/app/existing.ts. No diagnostics (correct).
3. Create apps/web/app/subdir/new.ts on disk:

export const b = [1, 2].findLast(x => x > 0);

4. Send workspace/didChangeWatchedFiles (type Created) for new.ts, then textDocument/didOpen it. The other order gives the same result.
5. Request textDocument/diagnostic for new.ts.

Same result with a {ws} folder, or with a plain path on a case-insensitive filesystem where apps/web/tsconfig.json has "include": ["App"] but the folder on disk is "app".

🙁 Actual behavior

new.ts is served by the parent project (lib: ES2015) instead of apps/web/tsconfig.json, so it gets false errors:

TS2550: Property 'findLast' does not exist on type 'number[]'. Do you need to change your target library? Try changing the 'lib' compiler option to 'es2023' or later.
(plus a follow-on TS7006 for the lambda parameter losing its contextual type)

The errors are still present 5 seconds later and only go away after restarting the language server.

🙂 Expected behavior

new.ts should belong to apps/web/tsconfig.json and have no diagnostics. That's what happens when the same layout is in a folder without [ or {, and with tsgo -p apps/web on the command line (it lists new.ts and reports 0 errors).

Additional information about the issue

Cause (at commit 4163ca1): for a file Created event, configfileregistrybuilder.go (~line 613) only checks ParsedCommandLine.PossiblyMatchesFileName, which matches against globs from WildcardDirectoryGlobs() (tsoptions/parsedcommandline.go ~317–318 and ~511–513). Those globs are built as /**/*.{ts,...} straight from the raw directory path, so:

• "[ws]" doesn't parse as a glob; the parse error is ignored and the glob is silently dropped.
• "{ws}" / "{b,c}" are read as alternation groups and "app[1-2]" as a character range, so the real folder name never matches.
• Matching is exact-case, even on case-insensitive filesystems.

Possible fix: don't build globs from filesystem paths. Either escape the special characters, or check the new file directly against the wildcard directories using caseSensitivity.PathKey (recursive dirs contain it, non-recursive dirs equal its parent, extension is supported). Also, don't silently drop patterns that fail to parse.

tsc --watch did not show the problem in my testing because a directory-change fallback picks the file up.

Tested with a synthetic LSP client, not VS Code.

AI disclosure: this issue was found and drafted with the help of an AI coding agent. I reviewed and reproduced it myself.