Turn `// @strict` off in all failing fourslash tests which do not contain baseline calls#63023

DanielRosenwasser · 2026-01-21T00:04:05Z

Part of #62333.

I did something similar to #62989, but looked for the first //\s+@ comment line, falling back to the first //// line. The script bails out if the word "baseline" appeared anywhere in the file.

Just like #62989, this doesn't get everything because @strict matches @strictNullChecks, so it's overly conservative. I'll have a follow-up PR for that.

…seline.

Copilot

Pull request overview

This pull request adds // @strict: false compiler directive to 135 fourslash test files that were previously failing with strict mode enabled. The changes are part of an effort to systematically address strict mode test failures by disabling strict mode for tests that do not use baseline verification.

Changes:

Adds // @strict: false directive to 135 fourslash test files
Directive is consistently placed after the reference path comment and before other compiler directives or test code
Changes are automated via script as described in PR description

Reviewed changes

Copilot reviewed 147 out of 147 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
tests/cases/fourslash/unusedVariableInClass4.ts	Added `// @strict: false` directive
tests/cases/fourslash/unusedVariableInClass2.ts	Added `// @strict: false` directive
tests/cases/fourslash/unusedVariableInClass1.ts	Added `// @strict: false` directive
tests/cases/fourslash/unusedTypeParametersInLambda4.ts	Added `// @strict: false` directive
tests/cases/fourslash/unusedTypeParametersInLambda3.ts	Added `// @strict: false` directive
tests/cases/fourslash/unusedParameterInLambda3.ts	Added `// @strict: false` directive
tests/cases/fourslash/unusedParameterInFunction2.ts	Added `// @strict: false` directive
tests/cases/fourslash/unusedClassInNamespace4.ts	Added `// @strict: false` directive
tests/cases/fourslash/underscoreTypings02.ts	Added `// @strict: false` directive
tests/cases/fourslash/unclosedArrayErrorRecovery.ts	Added `// @strict: false` directive
tests/cases/fourslash/superInDerivedTypeOfGenericWithStatics.ts	Added `// @strict: false` directive
tests/cases/fourslash/squiggleIllegalSubclassOverride.ts	Added `// @strict: false` directive
tests/cases/fourslash/squiggleFunctionExpression.ts	Added `// @strict: false` directive
tests/cases/fourslash/signatureHelpOptionalCall2.ts	Added `// @strict: false` directive
tests/cases/fourslash/signatureHelpCallExpressionJs.ts	Added `// @strict: false` directive
tests/cases/fourslash/refactorConvertToGetAccessAndSetAccess10.ts	Added `// @strict: false` directive
tests/cases/fourslash/quickInfoWidenedTypes.ts	Added `// @strict: false` directive
tests/cases/fourslash/quickInfoSignatureRestParameterFromUnion2.ts	Added `// @strict: false` directive
tests/cases/fourslash/quickInfoSignatureOptionalParameterFromUnion1.ts	Added `// @strict: false` directive
tests/cases/fourslash/quickInfoOnNarrowedTypeInModule.ts	Added `// @strict: false` directive
tests/cases/fourslash/quickInfoOnMergedModule.ts	Added `// @strict: false` directive
tests/cases/fourslash/quickInfoOnMergedInterfacesWithIncrementalEdits.ts	Added `// @strict: false` directive
tests/cases/fourslash/quickInfoOnCatchVariable.ts	Added `// @strict: false` directive
tests/cases/fourslash/quickInfoJsDocNonDiscriminatedUnionSharedProp.ts	Added `// @strict: false` directive
tests/cases/fourslash/quickInfoGenericTypeArgumentInference1.ts	Added `// @strict: false` directive
tests/cases/fourslash/quickInfoForShorthandProperty.ts	Added `// @strict: false` directive
tests/cases/fourslash/quickInfoForObjectBindingElementPropertyName03.ts	Added `// @strict: false` directive
tests/cases/fourslash/quickInfoForContextuallyTypedFunctionInTaggedTemplateExpression2.ts	Added `// @strict: false` directive
tests/cases/fourslash/pasteLambdaOverModule.ts	Added `// @strict: false` directive
tests/cases/fourslash/parenthesisFatArrows.ts	Added `// @strict: false` directive
tests/cases/fourslash/objectLiteralCallSignatures.ts	Added `// @strict: false` directive
tests/cases/fourslash/noSuggestionDiagnosticsOnParseError.ts	Added `// @strict: false` directive
tests/cases/fourslash/multiModuleFundule.ts	Added `// @strict: false` directive
tests/cases/fourslash/jsxAttributeSnippetCompletionUnclosed.ts	Added `// @strict: false` directive
tests/cases/fourslash/jsxAttributeSnippetCompletionClosed.ts	Added `// @strict: false` directive
tests/cases/fourslash/jsxAttributeSnippetCompletionAfterTypeArgs.ts	Added `// @strict: false` directive
tests/cases/fourslash/invertedCloduleAfterQuickInfo.ts	Added `// @strict: false` directive
tests/cases/fourslash/inheritedModuleMembersForClodule2.ts	Added `// @strict: false` directive
tests/cases/fourslash/incompatibleOverride.ts	Added `// @strict: false` directive
tests/cases/fourslash/getSemanticDiagnosticForDeclaration.ts	Added `// @strict: false` directive
tests/cases/fourslash/getDeclarationDiagnostics.ts	Added `// @strict: false` directive
tests/cases/fourslash/genericRespecialization1.ts	Added `// @strict: false` directive
tests/cases/fourslash/genericObjectBaseType.ts	Added `// @strict: false` directive
tests/cases/fourslash/genericMapTyping1.ts	Added `// @strict: false` directive
tests/cases/fourslash/genericInterfacePropertyInference2.ts	Added `// @strict: false` directive
tests/cases/fourslash/genericInterfacePropertyInference1.ts	Added `// @strict: false` directive
tests/cases/fourslash/functionTypes.ts	Added `// @strict: false` directive
tests/cases/fourslash/fixingTypeParametersQuickInfo.ts	Added `// @strict: false` directive
tests/cases/fourslash/extractFunctionContainingThis3.ts	Added `// @strict: false` directive
tests/cases/fourslash/extendsTArray.ts	Added `// @strict: false` directive
tests/cases/fourslash/extendInterfaceOverloadedMethod.ts	Added `// @strict: false` directive
tests/cases/fourslash/extendArrayInterfaceMember.ts	Added `// @strict: false` directive
tests/cases/fourslash/exportEqualTypes.ts	Added `// @strict: false` directive
tests/cases/fourslash/emptyArrayInference.ts	Added `// @strict: false` directive
tests/cases/fourslash/diagnosticsJsFileCompilationDuplicateFunctionImplementation.ts	Added `// @strict: false` directive
tests/cases/fourslash/derivedTypeIndexerWithGenericConstraints.ts	Added `// @strict: false` directive
tests/cases/fourslash/deprecatedInheritedJSDocOverload.ts	Added `// @strict: false` directive (contains baseline call - possible issue)
tests/cases/fourslash/defaultParamsAndContextualTypes.ts	Added `// @strict: false` directive
tests/cases/fourslash/contextualTypingOfArrayLiterals.ts	Added `// @strict: false` directive
tests/cases/fourslash/constEnumsEmitOutputInMultipleFiles.ts	Added `// @strict: false` directive
tests/cases/fourslash/consistentContextualTypeErrorsAfterEdits.ts	Added `// @strict: false` directive
tests/cases/fourslash/completionsOverridingMethod9.ts	Added `// @strict: false` directive
tests/cases/fourslash/completionListsThroughTransitiveBaseClasses2.ts	Added `// @strict: false` directive
tests/cases/fourslash/completionListsThroughTransitiveBaseClasses.ts	Added `// @strict: false` directive
tests/cases/fourslash/completionCloneQuestionToken.ts	Added `// @strict: false` directive
tests/cases/fourslash/codefixInferFromUsageNullish.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixUnusedIdentifier_suggestion.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixUnusedIdentifier_prefix.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixUnusedIdentifier_deleteWrite2.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixUndeclaredPropertyObjectLiteral.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixUndeclaredPropertyFunctionNonEmptyClass.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixUndeclaredPropertyFunctionEmptyClass.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixUndeclaredClassInstanceWithTypeParams.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixUndeclaredClassInstance.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixUndeclaredAcrossFiles1.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixSpellingVsMissingMember.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixRenameUnmatchedParameterJS3.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixRenameUnmatchedParameterJS2.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixRenameUnmatchedParameterJS1.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixOverrideModifier_js1.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixOverrideModifier9.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixOverrideModifier10.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixMissingTypeAnnotationOnExports28-long-types.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixInitializePrivatePropertyJS.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixInferFromUsageString.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixInferFromUsageRestParamJS.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixInferFromUsageRestParam2JS.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixInferFromUsageRestParam2.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixInferFromUsageRestParam.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixInferFromUsageOptionalParamJS.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixInferFromUsageOptionalParam.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixInferFromUsageInaccessibleTypes.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixInferFromUsageGetter2.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixInferFromUsageConstructorFunctionJS.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixInferFromUsageConstructor.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixForgottenThisPropertyAccess03.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixForgottenThisPropertyAccess02.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixForgottenThisPropertyAccess01.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixDisableJsDiagnosticsInFile8.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixDisableJsDiagnosticsInFile7.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixDisableJsDiagnosticsInFile6.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixCorrectReturnValue8.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixCorrectReturnValue20.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixCorrectReturnValue19.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixCorrectReturnValue18.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixCorrectReturnValue10.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixClassImplementInterfaceSomePropertiesPresent.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixClassImplementInterfaceOptionalProperty.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixClassImplementInterfaceMultipleImplementsIntersection2.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixClassImplementInterfaceMultipleImplements2.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixClassImplementInterfaceMultipleImplements1.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixClassImplementInterfaceHeritageClauseAlreadyHaveMember.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixClassImplementInterfaceDuplicateMember2.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixClassImplementInterfaceComputedPropertyNameWellKnownSymbols.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixClassImplementDeepInheritance.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixClassImplementClassPropertyTypeQuery.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixClassImplementClassPropertyModifiers.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixClassImplementClassMemberAnonymousClass.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixClassExtendAbstractSomePropertiesPresent.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixChangeJSDocSyntax15.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixCannotFindModule_suggestion.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixAwaitInSyncFunction6.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixAwaitInSyncFunction6.5.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixAddMissingProperties6.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixAddMissingProperties44.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixAddMissingProperties43.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixAddMissingProperties37.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixAddMissingProperties33.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixAddMissingProperties1.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixAddMissingEnumMember12.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixAddMissingDeclareProperty.ts	Added `// @strict: false` directive
tests/cases/fourslash/codeFixAddMissingAsync2.ts	Added `// @strict: false` directive
tests/cases/fourslash/cloduleTypeOf1.ts	Added `// @strict: false` directive
tests/cases/fourslash/cloduleAsBaseClass2.ts	Added `// @strict: false` directive
tests/cases/fourslash/cloduleAsBaseClass.ts	Added `// @strict: false` directive
tests/cases/fourslash/annotateWithTypeFromJSDoc9.ts	Added `// @strict: false` directive
tests/cases/fourslash/annotateWithTypeFromJSDoc9.5.ts	Added `// @strict: false` directive
tests/cases/fourslash/annotateWithTypeFromJSDoc8.ts	Added `// @strict: false` directive
tests/cases/fourslash/annotateWithTypeFromJSDoc7.ts	Added `// @strict: false` directive
tests/cases/fourslash/annotateWithTypeFromJSDoc6.ts	Added `// @strict: false` directive
tests/cases/fourslash/annotateWithTypeFromJSDoc3.ts	Added `// @strict: false` directive
tests/cases/fourslash/annotateWithTypeFromJSDoc18.ts	Added `// @strict: false` directive
tests/cases/fourslash/annotateWithTypeFromJSDoc17.ts	Added `// @strict: false` directive
tests/cases/fourslash/annotateWithTypeFromJSDoc12.ts	Added `// @strict: false` directive
tests/cases/fourslash/annotateWithTypeFromJSDoc11.ts	Added `// @strict: false` directive
tests/cases/fourslash/annotateWithTypeFromJSDoc10.ts	Added `// @strict: false` directive
tests/cases/fourslash/annotateWithTypeFromJSDoc1.ts	Added `// @strict: false` directive

Copilot · 2026-01-21T00:22:19Z

tests/cases/fourslash/deprecatedInheritedJSDocOverload.ts

@@ -1,3 +1,4 @@
+// @strict: false


This file contains a baseline call (verify.baselineQuickInfo() on line 31), but according to the PR description, the script should have "bailed out if the word 'baseline' appeared anywhere in the file." This file should not have received the // @strict: false directive addition.

It's true, but it's fine. I must have fiddled with this manually at some point.

DanielRosenwasser added 2 commits January 20, 2026 23:56

Add//@strict: falseto all failing fourslash tests that do not ba…
ec458cd
…seline.

Add files uncaught by the script.
5859dcb

typescript-bot assigned DanielRosenwasser Jan 21, 2026

typescript-bot added Author: Team For Uncommitted Bug PR for untriaged, rejected, closed or missing bug labels Jan 21, 2026

DanielRosenwasser marked this pull request as ready for review January 21, 2026 00:18

DanielRosenwasser requested review from RyanCavanaugh, Copilot and jakebailey January 21, 2026 00:18

Copilotstarted reviewing on behalf of DanielRosenwasser January 21, 2026 00:19 View session

CopilotAI reviewed Jan 21, 2026
View reviewed changes

DanielRosenwasser enabled auto-merge January 21, 2026 00:44

DanielRosenwasser mentioned this pull request Jan 21, 2026
Explicitly set strict: false for project tests, eval tests, and more programmatic fourslash tests #63024
Merged

jakebailey approved these changes Jan 21, 2026
View reviewed changes

DanielRosenwasser added this pull request to the merge queue Jan 21, 2026

Merged via the queue into main with commit c3dc61dJan 21, 2026
38 of 39 checks passed

DanielRosenwasser deleted the fourslashStrictness branch January 21, 2026 17:39

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Turn `// @strict` off in all failing fourslash tests which do not contain baseline calls#63023

Turn `// @strict` off in all failing fourslash tests which do not contain baseline calls #63023

DanielRosenwasser commented Jan 21, 2026•
edited
Loading

Uh oh!

CopilotAI left a comment

Uh oh!

CopilotAIJan 21, 2026

Uh oh!

DanielRosenwasserJan 21, 2026

Uh oh!

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

4 participants

Turn // @strict off in all failing fourslash tests which do not contain baseline calls#63023

Turn // @strict off in all failing fourslash tests which do not contain baseline calls #63023

Conversation

DanielRosenwasser commented Jan 21, 2026• edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

CopilotAI left a comment

Choose a reason for hiding this comment

Pull request overview

Reviewed changes

Uh oh!

CopilotAIJan 21, 2026

Choose a reason for hiding this comment

Uh oh!

DanielRosenwasserJan 21, 2026

Choose a reason for hiding this comment

Uh oh!

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

4 participants

Turn `// @strict` off in all failing fourslash tests which do not contain baseline calls#63023

Turn `// @strict` off in all failing fourslash tests which do not contain baseline calls #63023

DanielRosenwasser commented Jan 21, 2026•
edited
Loading