Unittest discovery out of memory

Environment data

• VS Code version: 1.60.2

• Extension version (available under the Extensions sidebar): v2021.9.1191016588

• OS and version: macOS Big Sur v11.5.2

• Python version (& distribution if applicable, e.g. Anaconda): 3.9.1

• Type of virtual environment used (N/A | venv | virtualenv | conda | …): venv

• Value of the python.languageServer setting: Pylance

• Extension Version working: v2021.8.1159798656

• Extension Version it stopped working: v2021.9.1191016588 up until latest

Expected behaviour

Clicking on the Testing icon results in the list of tests

Actual behaviour

VSCode crashes and says that I need to reload the window.

Steps to reproduce:

1. Open the project
2. Click on test icon
3. Crashes.

We have 1000+ test cases, I think VSCode just runs out of memory with this version of the extension.

Logs

<--- Last few GCs --->[77456:0x5000000000] 119227 ms: Scavenge (reduce) 3798.8 (3951.0) -> 3798.8 (3951.8) MB, 6.6 / 0.0 ms (average mu = 0.922, current mu = 0.825) allocation failure [77456:0x5000000000] 119248 ms: Scavenge (reduce) 3799.9 (3951.8) -> 3799.4 (3951.8) MB, 6.0 / 0.0 ms (average mu = 0.922, current mu = 0.825) allocation failure [77456:0x5000000000] 119270 ms: Scavenge (reduce) 3800.1 (3951.8) -> 3800.0 (3953.3) MB, 6.7 / 0.0 ms (average mu = 0.922, current mu = 0.825) allocation failure <--- JS stacktrace --->FATAL ERROR: MarkCompactCollector: young object promotion failed Allocation failed - JavaScript heap out of memory 1: 0x103c96a35 node::Buffer::New(v8::Isolate*, char*, unsigned long, void (*)(char*, void*), void*) [/Applications/Visual Studio Code.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework] 2: 0x103c96bd6 node::OnFatalError(char const*, char const*) [/Applications/Visual Studio Code.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework] 3: 0x104968023 v8::internal::FatalProcessOutOfMemory(v8::internal::Isolate*, char const*) [/Applications/Visual Studio Code.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework] 4: 0x104967f7f v8::internal::FatalProcessOutOfMemory(v8::internal::Isolate*, char const*) [/Applications/Visual Studio Code.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework] 5: 0x104a136c5 v8::internal::Heap::PreciseCollectAllGarbage(int, v8::internal::GarbageCollectionReason, v8::GCCallbackFlags) [/Applications/Visual Studio Code.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework] 6: 0x1016d17b2 v8::internal::MarkCompactCollector::EnsureSweepingCompleted() [/Applications/Visual Studio Code.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework] 7: 0x1016d0e71 v8::internal::MarkCompactCollector::EnsureSweepingCompleted() [/Applications/Visual Studio Code.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework] 8: 0x1016d0a9b v8::internal::MarkCompactCollector::EnsureSweepingCompleted() [/Applications/Visual Studio Code.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework] 9: 0x1016e9aeb v8::internal::MarkCompactCollector::EnsureSweepingCompleted() [/Applications/Visual Studio Code.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]10: 0x102d34486 v8::internal::SetupIsolateDelegate::SetupHeap(v8::internal::Heap*) [/Applications/Visual Studio Code.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]11: 0x102d34813 v8::internal::SetupIsolateDelegate::SetupHeap(v8::internal::Heap*) [/Applications/Visual Studio Code.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]12: 0x1016d77ba v8::internal::MarkCompactCollector::EnsureSweepingCompleted() [/Applications/Visual Studio Code.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]13: 0x1016d6d63 v8::internal::MarkCompactCollector::EnsureSweepingCompleted() [/Applications/Visual Studio Code.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]14: 0x1016c621f v8::internal::LocalHeap::InvokeGCEpilogueCallbacksInSafepoint() [/Applications/Visual Studio Code.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]15: 0x1016c3c90 v8::internal::LocalHeap::InvokeGCEpilogueCallbacksInSafepoint() [/Applications/Visual Studio Code.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]16: 0x10169df50 v8::internal::Heap::MaxRegularHeapObjectSize(v8::internal::AllocationType) [/Applications/Visual Studio Code.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]17: 0x10166c9e2 v8::internal::FactoryBase<v8::internal::Factory>::NewRawOneByteString(int, v8::internal::AllocationType) [/Applications/Visual Studio Code.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]18: 0x1018c040e v8::internal::String::SlowFlatten(v8::internal::Isolate*, v8::internal::Handle<v8::internal::ConsString>, v8::internal::AllocationType) [/Applications/Visual Studio Code.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]19: 0x1018c3f1c v8::internal::String::SlowEquals(v8::internal::Isolate*, v8::internal::Handle<v8::internal::String>, v8::internal::Handle<v8::internal::String>) [/Applications/Visual Studio Code.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]20: 0x1019ac4c2 v8::internal::Runtime::SetObjectProperty(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]21: 0x50000b22b8

Extension host terminated unexpectedly. Code: null Signal: SIGABRT _onExtensionHostCrashed @ abstractExtensionService.ts:615 _onExtensionHostCrashed @ extensionService.ts:252 _onExtensionHostCrashOrExit @ abstractExtensionService.ts:607 (anonymous) @ abstractExtensionService.ts:597 fire @ event.ts:577 _onExtHostProcessExit @ localProcessExtensionHost.ts:535 (anonymous) @ localProcessExtensionHost.ts:289 emit @ events.js:315 ChildProcess._handle.onexit @ internal/child_process.js:277

[karthiknadig]

There was a rendering bug that was fixed in VS Code when we tried to add a large number of tests to the test tree. That potentially addressed this as well.

[ZackTherrien]

In the latest version I get the following error in the Devtools

<--- JS stacktrace --->FATAL ERROR: MarkCompactCollector: young object promotion failed Allocation failed - JavaScript heap out of memory