Semantic-tokens panic while typing out a match/case statement #2417
Description
Summary
I'm getting repeated semantic-tokens panics in the server while typing out match/case statements in a Python project. I managed to create this standalone video to reproduce it:
Screen.Recording.2026-01-09.at.14.24.53.mov
The code at the end of the video was:
import ast
def f(x: ast.AST):
match x:
case ast.Attribute(value=ast.Name(id), attr)and the logs are:
2026-01-09 14:24:20.637830000 INFO Version: ruff/0.14.10+238 (de9f3f90e 2026-01-07)
2026-01-09 14:24:20.656786000 INFO Defaulting to python-platform `darwin`
2026-01-09 14:24:20.657848000 INFO Python version: Python 3.13, platform: darwin
2026-01-09 14:24:20.664373000 INFO Indexed 1 file(s) in 0.004s
2026-01-09 14:24:27.673639000 INFO Defaulting to python-platform `darwin`
2026-01-09 14:24:27.674723000 INFO Python version: Python 3.13, platform: darwin
2026-01-09 14:24:27.678103000 INFO Indexed 1 file(s) in 0.003s
[Error - 14:24:42] Request textDocument/documentSymbol failed.
Error: name must not be falsy
at bp.validate (file:///Applications/Visual%20Studio%20Code.app/Contents/Resources/app/out/vs/workbench/api/node/extensionHostProcess.js:112:26946)
at new bp (file:///Applications/Visual%20Studio%20Code.app/Contents/Resources/app/out/vs/workbench/api/node/extensionHostProcess.js:112:27235)
at V (/Users/alexw/.vscode/extensions/astral-sh.ty-2026.2.0-darwin-arm64/dist/extension.js:1:275579)
at c (/Users/alexw/.vscode/extensions/astral-sh.ty-2026.2.0-darwin-arm64/dist/extension.js:1:18138)
at t.map (/Users/alexw/.vscode/extensions/astral-sh.ty-2026.2.0-darwin-arm64/dist/extension.js:1:18224)
at Object.asDocumentSymbols (/Users/alexw/.vscode/extensions/astral-sh.ty-2026.2.0-darwin-arm64/dist/extension.js:1:283635)
at i (/Users/alexw/.vscode/extensions/astral-sh.ty-2026.2.0-darwin-arm64/dist/extension.js:1:347081)
at runNextTicks (node:internal/process/task_queues:65:5)
at process.processImmediate (node:internal/timers:453:9)
at process.callbackTrampoline (node:internal/async_hooks:130:17)
at async RN.provideDocumentSymbols (file:///Applications/Visual%20Studio%20Code.app/Contents/Resources/app/out/vs/workbench/api/node/extensionHostProcess.js:144:140602)
[Error - 14:24:42] Request textDocument/documentSymbol failed.
Error: name must not be falsy
at bp.validate (file:///Applications/Visual%20Studio%20Code.app/Contents/Resources/app/out/vs/workbench/api/node/extensionHostProcess.js:112:26946)
at new bp (file:///Applications/Visual%20Studio%20Code.app/Contents/Resources/app/out/vs/workbench/api/node/extensionHostProcess.js:112:27235)
at V (/Users/alexw/.vscode/extensions/astral-sh.ty-2026.2.0-darwin-arm64/dist/extension.js:1:275579)
at c (/Users/alexw/.vscode/extensions/astral-sh.ty-2026.2.0-darwin-arm64/dist/extension.js:1:18138)
at t.map (/Users/alexw/.vscode/extensions/astral-sh.ty-2026.2.0-darwin-arm64/dist/extension.js:1:18224)
at Object.asDocumentSymbols (/Users/alexw/.vscode/extensions/astral-sh.ty-2026.2.0-darwin-arm64/dist/extension.js:1:283635)
at i (/Users/alexw/.vscode/extensions/astral-sh.ty-2026.2.0-darwin-arm64/dist/extension.js:1:347081)
at async RN.provideDocumentSymbols (file:///Applications/Visual%20Studio%20Code.app/Contents/Resources/app/out/vs/workbench/api/node/extensionHostProcess.js:144:140602)
2026-01-09 14:25:20.141538000 ERROR An error occurred with request ID 369: request handler panicked at crates/ty_ide/src/semantic_tokens.rs:248:9:
Tokens must be added in file order: previous token ends at Some(89), new token starts at 77query stacktrace:
run with `RUST_BACKTRACE=1` environment variable to display a backtrace
[Error - 14:25:20] Request textDocument/semanticTokens/full failed.
Message: request handler panicked at crates/ty_ide/src/semantic_tokens.rs:248:9:
Tokens must be added in file order: previous token ends at Some(89), new token starts at 77query stacktrace:
run with `RUST_BACKTRACE=1` environment variable to display a backtrace
Code: -32603
2026-01-09 14:25:20.562263000 ERROR An error occurred with request ID 377: request handler panicked at crates/ty_ide/src/semantic_tokens.rs:248:9:
Tokens must be added in file order: previous token ends at Some(91), new token starts at 77query stacktrace:
run with `RUST_BACKTRACE=1` environment variable to display a backtrace
[Error - 14:25:20] Request textDocument/semanticTokens/full failed.
Message: request handler panicked at crates/ty_ide/src/semantic_tokens.rs:248:9:
Tokens must be added in file order: previous token ends at Some(91), new token starts at 77query stacktrace:
run with `RUST_BACKTRACE=1` environment variable to display a backtrace
Code: -32603
Version
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