eslint-plugin-mdx v2 causes OOM errors in VSCode

[mshick]

I've been using eslint-plugin-mdx v1 with the VSCode eslint/mdx extensions for some time, so I know how it generally works. Ever since v2 was released I've been unable to use it on several projects due to OOM errors in VSCode like attached.

I've created a minimal reproduction with a default create-next-app blog, just to have something more like a real world situation. I've set it up as the results of running npx create-next-app, following the set-up for the dbaeumer.vscode-eslint, jounqin.vscode-mdx and eslint-plugin-mdx. When I run eslint from the CLI it works as expected, with my prettier rules applied and errors correctly triggered. The eslint-driven formatting in VSCode even functions as expected until the OOMs cause the eslint server to shut down.

I can't help feel like I'm missing something, since no incompatibilities are noted on the relevant projects, nor has Google turned up anything. I don't have any other extensions enabled that affect MDX, as far as I can tell.

Here is my minimal repro: https://github.com/mshick/eslint-mdx-next

[Error - 2:22:48 PM] Connection to server got closed. Server will not be restarted.
[Info  - 2:22:48 PM] ESLint server stopped.
[Info  - 2:36:09 PM] ESLint server is starting
[Info  - 2:36:10 PM] ESLint server running in node v16.13.0
[Info  - 2:36:10 PM] ESLint server is running.
[Info  - 2:36:10 PM] ESLint library loaded from: /Users/mshick/Code/mshick/eslint-mdx-next/nextjs-blog/node_modules/eslint/lib/api.js

<--- Last few GCs --->

[91719:0x120798000]       44 ms: Mark-sweep (reduce) 1.4 (4.5) -> 1.4 (3.2) MB, 1.6 / 0.0 ms  (average mu = 0.076, current mu = 0.000) last resort GC in old space requested
[91719:0x120798000]       45 ms: Mark-sweep (reduce) 1.4 (3.2) -> 1.4 (3.0) MB, 1.0 / 0.0 ms  (average mu = 0.043, current mu = 0.000) last resort GC in old space requested


<--- JS stacktrace --->

FATAL ERROR: CALL_AND_RETRY_LAST Allocation failed - JavaScript heap out of memory
 1: 0x10d8bde6c node::FatalException(v8::Isolate*, v8::TryCatch const&) [/Applications/Visual Studio Code.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]
 2: 0x10d8bdff4 node::OnFatalError(char const*, char const*) [/Applications/Visual Studio Code.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]
 3: 0x1095d6c44 v8::internal::FatalProcessOutOfMemory(v8::internal::Isolate*, char const*) [/Applications/Visual Studio Code.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]
 4: 0x1095d6b74 v8::internal::FatalProcessOutOfMemory(v8::internal::Isolate*, char const*) [/Applications/Visual Studio Code.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]
 5: 0x109788bf0 v8::internal::Heap::StartIncrementalMarking(int, v8::internal::GarbageCollectionReason, v8::GCCallbackFlags) [/Applications/Visual Studio Code.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]
 6: 0x1097991b0 v8::internal::Heap::AllocatedExternalMemorySinceMarkCompact() [/Applications/Visual Studio Code.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]
 7: 0x109762960 v8::internal::Factory::CodeBuilder::BuildInternal(bool) [/Applications/Visual Studio Code.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]
 8: 0x109762b70 v8::internal::Factory::CodeBuilder::Build() [/Applications/Visual Studio Code.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]
 9: 0x109d7a820 v8::internal::RegExpMacroAssemblerARM64::GetCode(v8::internal::Handle<v8::internal::String>) [/Applications/Visual Studio Code.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]
10: 0x109b1d39c v8::internal::CharacterRange::IsCanonical(v8::internal::ZoneList<v8::internal::CharacterRange>*) [/Applications/Visual Studio Code.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]
11: 0x109b452c8 v8::internal::RegExp::Exec(v8::internal::Isolate*, v8::internal::Handle<v8::internal::JSRegExp>, v8::internal::Handle<v8::internal::String>, int, v8::internal::Handle<v8::internal::RegExpMatchInfo>, v8::internal::RegExp::ExecQuirks) [/Applications/Visual Studio Code.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]
12: 0x109b44a2c v8::internal::RegExp::Exec(v8::internal::Isolate*, v8::internal::Handle<v8::internal::JSRegExp>, v8::internal::Handle<v8::internal::String>, int, v8::internal::Handle<v8::internal::RegExpMatchInfo>, v8::internal::RegExp::ExecQuirks) [/Applications/Visual Studio Code.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]
13: 0x109b42834 v8::internal::RegExp::Exec(v8::internal::Isolate*, v8::internal::Handle<v8::internal::JSRegExp>, v8::internal::Handle<v8::internal::String>, int, v8::internal::Handle<v8::internal::RegExpMatchInfo>, v8::internal::RegExp::ExecQuirks) [/Applications/Visual Studio Code.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]
14: 0x109b9dff4 v8::internal::Runtime::DefineObjectOwnProperty(v8::internal::Isolate*, v8::internal::Handle<v8::internal::Object>, v8::internal::Handle<v8::internal::Object>, v8::internal::Handle<v8::internal::Object>, v8::internal::StoreOrigin, v8::Maybe<v8::internal::ShouldThrow>) [/Applications/Visual Studio Code.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]
15: 0x7407f0a06c 
16: 0x7407f6c8a0 
17: 0x7407e8d758 
18: 0x7407e8d758 
19: 0x7407e8d758 
20: 0x7407e8d758 
21: 0x7407e8d758 
22: 0x7407e8d758 
23: 0x7407e8d758 
24: 0x7407e8d758 
25: 0x7407e8d758 
26: 0x7407e8d758 
27: 0x7407e8d758 
28: 0x7407e8d758 
29: 0x7407e8d758 
30: 0x7407e8d758 
31: 0x7407e8d758 
32: 0x7407e8d758 
33: 0x7407e8b42c 
34: 0x7407e8b0c8 
35: 0x10970174c v8::internal::Execution::Call(v8::internal::Isolate*, v8::internal::Handle<v8::internal::Object>, v8::internal::Handle<v8::internal::Object>, int, v8::internal::Handle<v8::internal::Object>*) [/Applications/Visual Studio Code.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]
36: 0x1095f4c68 v8::Function::Call(v8::Local<v8::Context>, v8::Local<v8::Value>, int, v8::Local<v8::Value>*) [/Applications/Visual Studio Code.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]
37: 0x10d82a084 node::CallbackScope::~CallbackScope() [/Applications/Visual Studio Code.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]
38: 0x10d83cbc0 node::EmitAsyncDestroy(node::Environment*, node::async_context) [/Applications/Visual Studio Code.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]
39: 0x10d903474 node::CommonEnvironmentSetup::context() const [/Applications/Visual Studio Code.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]
40: 0x10824f3f0 uv_async_send [/Applications/Visual Studio Code.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]
41: 0x108260214 uv_free_interface_addresses [/Applications/Visual Studio Code.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]
42: 0x10824f80c uv_run [/Applications/Visual Studio Code.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]
43: 0x10d8ff74c node::SpinEventLoop(node::Environment*) [/Applications/Visual Studio Code.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]
44: 0x10d95ed48 node::PromiseRejectCallback(v8::PromiseRejectMessage) [/Applications/Visual Studio Code.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]
45: 0x10d961a20 node::PromiseRejectCallback(v8::PromiseRejectMessage) [/Applications/Visual Studio Code.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]
46: 0x1a5a5426c _pthread_start [/usr/lib/system/libsystem_pthread.dylib]
47: 0x1a5a4f08c thread_start [/usr/lib/system/libsystem_pthread.dylib]
[Info  - 2:36:18 PM] Connection to server got closed. Server will restart.
[Info  - 2:36:18 PM] ESLint server stopped.
[Info  - 2:36:18 PM] ESLint server is starting
[Info  - 2:36:18 PM] ESLint server running in node v16.13.0
[Info  - 2:36:18 PM] ESLint server is running.
[Info  - 2:36:18 PM] ESLint library loaded from: /Users/mshick/Code/mshick/eslint-mdx-next/nextjs-blog/node_modules/eslint/lib/api.js

<--- Last few GCs --->

[wooorm]

/cc @JounQin

[mshick]

Just to add a little more detail:

• I've disabled all VSCode extensions, restarted, then loaded the eslint and vscode-mdx extensions. The OOM errors begin right after enabling vscode-mdx. After another restart they persist.
• I've attempted switching to the pre-release version of the eslint extension, no difference.

Here is my VSCode info:

Version: 1.68.1
Commit: 30d9c6cd9483b2cc586687151bcbcd635f373630
Date: 2022-06-14T12:48:37.209Z (2 wks ago)
Electron: 17.4.7
Chromium: 98.0.4758.141
Node.js: 16.13.0
V8: 9.8.177.13-electron.0
OS: Darwin arm64 21.5.0

[JounQin]

So why not a vscode-eslint issue? eslint cli runs without any problem, right?

eslint-mdx@v2 runs a worker inside through synckit.

Personally I don't have too much experience about VSCode extension.

---

See https://github.com/mdx-js/vscode-mdx#known-vscode-eslint-issues

[JounQin]

I raised microsoft/vscode-eslint#1498 for tracking.

[JounQin]

@mshick See microsoft/vscode-eslint#1498 (comment)

"eslint.runtime": "node" will do the trick.

[JounQin]

I'll add it into vscode-mdx's document.

[JounQin]

I'll add it into vscode-mdx's document.

Done. https://github.com/mdx-js/vscode-mdx#known-vscode-eslint-issues

[mshick]

@JounQin Thanks for finding this. Working well for me.