[tqchen]

This PR refactors test infrastructure by removing the CompareBeforeAfter base class from tvm.testing and converting all dependent tests to use a simpler, more explicit pattern.

We need this change as latest pytest do not allow calling fixture as inner patterns which the previous CompareBeforeAfter depend on.

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Summary of Changes

Hello @tqchen, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request significantly updates the testing framework by eliminating a problematic base class and migrating its usages to a more direct and compatible approach. The change improves the robustness of the test suite against external library updates and simplifies the overall structure of individual tests, making them easier to understand and maintain.

Highlights

• Refactor Test Infrastructure: The CompareBeforeAfter base class from tvm.testing has been removed, streamlining the test setup for TIR transformations.
• Pytest Compatibility: This refactoring addresses an incompatibility with recent pytest versions that no longer allow calling fixtures as inner patterns, which the old CompareBeforeAfter class relied upon.
• Simplified Test Patterns: All dependent tests have been converted from class-based structures to simpler, more explicit function-based patterns, directly embedding transformation logic and structural assertions.

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Changelog

• python/tvm/testing/utils.py
  • Removed the CompareBeforeAfter class entirely, as it was no longer compatible with recent pytest versions.
• tests/python/dlight/test_cpu_gemv.py
  • Converted class-based tests (BaseBeforeAfter, TestGEMV) to a standalone function (test_gemv_basic).
  • Moved transformation logic and structural assertions directly into the test function.
  • Updated T.prim_func decorators to include private=True.
• tests/python/dlight/test_gpu_conv.py
  • Converted class-based tests (BaseBeforeAfter, TestConv3d) to a standalone function (test_conv3d).
  • Moved transformation logic and structural assertions directly into the test function.
  • Removed pytest import as it's no longer directly used.
  • Updated T.prim_func decorators to include private=True.
• tests/python/dlight/test_gpu_gemv.py
  • Converted class-based tests (BaseBeforeAfter, TestGEMV) to a standalone function (test_gemv_basic).
  • Moved transformation logic and structural assertions directly into the test function.
  • Removed pytest import as it's no longer directly used.
  • Updated T.prim_func decorators to include private=True.
• tests/python/dlight/test_gpu_matmul.py
  • Converted multiple class-based tests (TestMatmul, TestFusedMatmul, TestSkipGEMV, TestOutputFP32, TestInlineConsumerChain, AndroidBeforeAfter, TestMatmulAndroid, MetalBeforeAfter, TestMatmulMetal, TestMatmulMetalInt4Quant) to standalone functions.
  • Moved transformation logic and structural assertions directly into the test functions.
  • Removed pytest import as it's no longer directly used.
  • Updated T.prim_func decorators to include private=True and removed global_symbol attributes where appropriate.
• tests/python/dlight/test_gpu_matmul_tensorize.py
  • Converted multiple class-based tests (TestMatmulTensorize, TestMatmulTensorizeTooSmall, TestMatmulTensorizeEpilogue, TestMatmulInt8Tensorize, TestMatmulInt8Tensorize3d2dDyn, MetalBeforeAfter, TestMatmulMetal) to standalone functions.
  • Moved transformation logic and structural assertions directly into the test functions.
  • Removed pytest import as it's no longer directly used.
  • Updated T.prim_func decorators to include private=True and removed global_symbol attributes where appropriate.
• tests/python/meta_schedule/test_meta_schedule_postproc_rewrite_layout.py
  • Converted class-based tests (BaseBeforeAfter, TestTIRMatmul, TestRewrittenBuffersMustOccurWithinBlock, TestExtentOne, TestLayoutRewriteInt64Index) to standalone functions.
  • Introduced a helper function _apply_rewrite_layout to encapsulate the transformation logic.
  • Added pytest import.
  • Updated T.prim_func decorators to include private=True and removed global_symbol attributes where appropriate.
• tests/python/relax/test_transform_compute_prim_value.py
  • Converted class-based tests (BaseCompare, TestPrimValueInAssertCondition, TestPrimValueInBranchCondition, TestPrimValueInPureFunction) to standalone functions.
  • Moved transform application and structural assertions inline within the test functions.
• tests/python/relax/test_transform_convert_dataflow.py
  • Converted class-based tests (ExtractCompare, TestTrivial, TestBasic, TestMultipleBlocks, TestExtractInsideBranches, TestTreatNonCallAsPure, TestImpureInnerFunction, TestPureInnerFunction, TestImpureExternalFunction, TestPureExternalFunction, TestMergeWithPrecedingDataflowBlock, TestMergeWithNextDataflowBlock, TestPreserveExistingDataflowBlocksAtBeginning, TestPreserveExistingDataflowBlocksAtEnd) to standalone functions.
  • Moved transform application and structural assertions inline within the test functions.
• tests/python/relax/test_transform_expand_tuple_args.py
  • Converted class-based tests (BaseCompare, TestSimple, TestNested) to standalone functions.
  • Moved transform application and structural assertions inline within the test functions.
• tests/python/relax/test_transform_remove_unused_outputs.py
  • Converted class-based tests (BaseCompare, TestSimple, TestUseMultipleOutputs, TestMultipleCallSites, TestReturnTuple) to standalone functions.
  • Moved transform application and structural assertions inline within the test functions.
• tests/python/relax/test_transform_remove_unused_parameters.py
  • Converted class-based tests (BaseCompare, TestRemoveUnusedRelaxParameter, TestReplaceSymbolicVariables, TestNoExtraSymbolicVariables, TestRemoveExtraPrimVariables, TestRemoveExtraShapeVariables) to standalone functions.
  • Moved transform application and structural assertions inline within the test functions.
• tests/python/relax/test_transform_rewrite_cuda_graph.py
  • Converted class-based tests (BaseCompare, TestNullValue, TestMergeAllocFuncs, TestDisableCaptureOutput, TestStaticInputWithSymbolicShape) to standalone functions.
  • Moved transform application and structural assertions inline within the test functions.
• tests/python/relax/test_transform_topological_sort.py
  • Converted multiple class-based tests (TestDepthFirstFromInputs, TestDepthFirstFromInputWithConstant, TestDepthFirstFromInputWithMultipleInputs, TestDepthFirstBreakTiesByExistingOrder, TestDepthFirstFromOutput, TestDepthFirstFromOutputTupleWithBinding, TestDepthFirstFromOutputTupleWithoutBinding, TestDepthFirstFromOutputWithUnusedVariables, TestDepthFirstFromInputWithUnusedParameters, TestBreadthFirst, TestBreadthFirstBreakTiesByExistingOrder) to standalone functions.
  • Moved transform application and structural assertions inline within the test functions.
• tests/python/testing/test_tvm_testing_before_after.py
  • Removed the BaseBeforeAfter class.
  • Converted all test classes (TestBeforeAfterPrimFunc, TestBeforeAfterMethod, TestBeforeAfterFixture, TestBeforeAfterDelayedPrimFunc, TestBeforeAfterParametrizedFixture, TestBeforeAfterIRModule, TestBeforeAfterIRModuleExplicitFixture) to standalone functions.
  • Updated T.prim_func decorators to include private=True.
• tests/python/tir-analysis/test_tir_analysis_identify_memcpy.py
  • Removed the BaseTest class.
  • Converted all test classes to standalone functions.
  • Introduced a helper function _check_memcpy_results for result validation.
• tests/python/tir-base/test_slice_tir.py
  • Converted class-based tests (TestParseCallTIR, TestAnnotateAndSliceTIR) to standalone functions.
  • Updated T.prim_func decorators to include private=True.
• tests/python/tir-base/test_tir_stmt_functor_substitute.py
  • Converted class-based tests (BaseCompare, TestBasicSubstitute, TestSubstituteAllocate, TestSubstituteBufferLoad, TestSubstituteDeclBuffer) to standalone functions.
  • Introduced a helper function _apply_substitute for applying the transform.
• tests/python/tir-schedule/test_tir_schedule_reduction.py
  • Converted the TestDecomposeReductionWithThreadBinding class to a standalone function.
• tests/python/tir-schedule/test_tir_schedule_set_axis_separator.py
  • Converted the TestIndexedLookup class to a standalone function.
• tests/python/tir-schedule/test_tir_schedule_transform_layout.py
  • Converted multiple class-based tests (TestTransformLayoutWithCacheWriteAndAxisSeparators, BasePaddingCompare, TestNoPadding, TestNoPaddingMultipleUsage, TestNoPaddingOpaqueBlock, TestErrorIfPaddingForbidden, TestImplicitPaddingAssumeInjective, TestErrorOnWrongPaddingType, TestErrorOnNonMatchingTypes, TestPaddedTransformIfThenElse, TestPaddedTransformWithoutLoop, TestPaddedTransformIfThenElseReduction, TestPaddedTransformIfThenElseReductionOpaque, TestPaddedTransformPostProcIfRequiredDueToSideEffects, TestPaddedTransformOfInputCreatesAssumption, TestPaddedTransformNonConstantValue, TestPaddedTransformRepeatedBufferElement, TestPadValueMayNotReferenceOtherBuffer, TestTransformLayoutWithVar, TestTransformWithAxisSeparators, TestTransformWithAxisSeparatorsOpaqueBlock) to standalone functions.
• tests/python/tir-transform/test_tir_transform_annotate_device_regions.py
  • Converted class-based tests (BaseCompare, TestAnnotateThreadExtent, TestAnnotateDeviceScope) to standalone functions.
• tests/python/tir-transform/test_tir_transform_annotate_irregular_loop.py
  • Converted class-based tests (BaseCompare, TestAnnotateLoopWithBreak, TestAnnotateLoopWithContinue, TestNestedIrregularBothLoops, TestWhileLoopWithBreak, TestBreakInNestedConditional, TestWhileLoopWithBreakStandalone, TestNestedIrregularLoopStandalone) to standalone functions.
• tests/python/tir-transform/test_tir_transform_combine_context_call.py
  • Converted class-based tests (TestCombineContextsInLoop, TestCombineContextsInLoopWithoutTarget) to standalone functions.
• tests/python/tir-transform/test_tir_transform_convert_blocks_to_opaque.py
  • Converted the TestErrorIfPredicateUsesBlockVariables class to a standalone function.
• tests/python/tir-transform/test_tir_transform_convert_ssa.py
  • Converted multiple class-based tests (BaseBeforeAfter, TestReuseInSequentialLetStmt, TestReuseInNestedLetStmt, TestReusedVarAcrossModule, TestReusedParameter, TestReusedBufferObj, TestReusedBufferParameter, TestKeepDuplicateThreadIdxInSameFunction, TestDeDuplicateThreadIdxAcrossMultipleFunctions, TestDeDuplicateThreadIdxIterVarAcrossMultipleFunctions, TestThreadIdxReusedWithinAndAcrossFunctions, TestTrackForwardDeclarationsInAttrStmt) to standalone functions.
• tests/python/tir-transform/test_tir_transform_device_kernel_launch.py
  • Converted class-based tests (BaseCompare, TestLowerDeviceKernelLaunch, TestExternallyVisibleKernelLaunch, TestCollectLaunchParameter, TestSameDeviceDifferentTarget) to standalone functions.
• tests/python/tir-transform/test_tir_transform_flatten_buffer.py
  • Converted multiple class-based tests (BaseCompare, TestElementwise, TestElementwiseWithoutDeclBuffer, TestGPU, TestSymbolic, TestFusedSymbolic, TestFusedSymbolicWithPredicate, TestMultiAlloc, TestStrided, TestBoolean, TestFlattenInsideBlock, TestNoChangeTo2DPhysicalBuffer, TestFlattenAllocBufferWithAxisSeparators, TestFlattenDeclBufferWithAxisSeparators) to standalone functions.
• tests/python/tir-transform/test_tir_transform_helpers.py
  • Converted multiple class-based tests (TestBindTarget, TestBindTargetWithHostToExposedFunction, TestBindTargetWithHostToInternalFunction, TestBindTargetIgnoresExisting, TestBindTargetUpdatesHost, TestBindTargetMultipleFunctions, TestBindTargetWithDeviceHostCallSameFunc, TestFilterRemovesGlobalVarMap) to standalone functions.
• tests/python/tir-transform/test_tir_transform_hoist_expression.py
  • Converted multiple class-based tests (BaseBeforeAfter, TestHoistToTop, TestSuppressHoistIfElse, TestHoistBlockVar, TestSuppressHoistBlockVar, TestHoistAcrossBlockVar, TestSuppressHoistAcrossBlockVar, TestHoistToMiddle, TestHoistWithLet, TestHoistDisableLet, TestHoistIfElse, TestHoistSequentialAssign, TestHoistMultiIf, TestHoistComplexConditional, TestSuppressSplittingConditional, TestHoistMultiIfElse, TestHoistMultiIfElseDifferentBranches, TestHoistIfElseExpr, TestSuppressHoistIfElseExpr, TestHoistLetExpr, TestSuppressHoistLetExpr) to standalone functions.
• tests/python/tir-transform/test_tir_transform_inject_double_buffer.py
  • Converted class-based tests (TestDoubleBuffer, TestDoubleBufferWithDeclBuffer) to standalone functions.
• tests/python/tir-transform/test_tir_transform_inject_ptx_async_copy.py
  • Converted the TestMultiplicationNodesAreInligned class to a standalone function.
• tests/python/tir-transform/test_tir_transform_lower_device_storage_access_info.py
  • Converted class-based tests (BaseCompare, TestLowerCPUAccessibleScope, TestLowerCPUAccessibleScopeWithDeclBuffer, TestLowerCPUInaccessibleScope, TestLowerCPUInaccessibleScopeWithDeclBuffer) to standalone functions.
• tests/python/tir-transform/test_tir_transform_lower_thread_all_reduce.py
  • Converted multiple class-based tests (BaseCompare, BaseFailure, TestBasic, TestBasicWithDeclBuffer, TestReduceSummation, TestMultiGroupReduction, TestMultiGroupMask1, TestMultiWarpReduce1, TestMultiWarpReduce2, TestMultiGroupMultiWarpReduction, TestMultiGroupMultiWarpPredicatedReduction, TestMetalNoMask) to standalone functions.
• tests/python/tir-transform/test_tir_transform_lower_tvm_builtin.py
  • Converted class-based tests (TestLowerDeviceAllocate, TestLowerCPUAllocation, TestLowerAllocateRequiresDeviceID, TestLowerAllocateRequiresDeviceType, TestLowerCPUAllocWithFunctionAttr) to standalone functions.
• tests/python/tir-transform/test_tir_transform_make_unpacked_api.py
  • Converted class-based tests (TestTargetHostRemoved, TestInternalSubroutineCall, TestSubroutineCallToExternallyVisibleSubroutine, TestCallExternallyVisibleSubroutineWithDLTensor) to standalone functions.
• tests/python/tir-transform/test_tir_transform_merge_dynamic_shared_memory_allocations.py
  • Converted multiple class-based tests (TestMatmul, TestSimpleAllocNoReuse, TestSimpleAllocReuse, TestAsyncCopy) to standalone functions.
• tests/python/tir-transform/test_tir_transform_pointer_value_type_rewrite.py
  • Converted class-based tests (BaseCompare, TestRewriteToShuffle0, TestRewriteToShuffle1, TestAddressOf, TestScalarReadWithoutWrite) to standalone functions.
• tests/python/tir-transform/test_tir_transform_reduce_branching_through_overcompute.py
  • Converted multiple class-based tests (BaseBeforeAfter, TestIntroduceNoOp, TestIntroduceAdditionOfZero, TestIntroduceAdditionOfKnownZeroInBuffer, TestIntroduceOverwrittenWrite, TestMaintainValuesUsedLater, TestIdentifyOverwrittenWriteFromEquivalentExpressions, TestIntroduceSupersetOverwrittenWrite) to standalone functions.
• tests/python/tir-transform/test_tir_transform_remove_assume.py
  • Converted class-based tests (BaseBeforeAfter, TestRemoveAssume, TestRemoveAssumeLoop) to standalone functions.
• tests/python/tir-transform/test_tir_transform_remove_no_op.py
  • Converted multiple class-based tests (BaseBeforeAfter, TestRemoveEmptyForLoop, TestRemoveZeroExtentLoop, TestRemoveUnusedLet, TestRemoveLetUsedOnlyInNoOp, TestKeepSideEffectsOfLet, TestRemoveEmptyThenCase, TestRemoveEmptyElseCase, TestRemoveUnusedWrite, TestSuppressRemovalOfUnusedWrite, TestKeepSideEffectsOfUnusedWrite, TestKeepFirstWriteWhenUsed, TestRemoveOverwrittenLoop, TestRemoveOverwrittenSubloop, TestKeepPartiallyOverwrittenLoop, TestRemoveOverwrittenPredicatedLoopWithIdenticalCondition, TestRemoveOverwrittenPredicatedLoopWithProvableCondition, TestRemoveSeparatedOverwrites, TestRemoveSeparatedOverwriteOfPredicatedLoop, TestRemoveReadWrite, TestKeepReadWriteToDifferentIndices, TestRemoveReadWriteSameIndexDifferentExpression, TestRemoveReadWriteSameIndexUsingConstraint, TestRemoveWritingOfKnownValue, TestKeepOneOfDuplicateLoops, TestRemoveEmptyTemporary, TestRemoveEmptyTemporaryWithDeclBuffer, TestRemoveUnusedTemporary, TestRemoveUnusedWriteIntoTemporary, TestKeepUsedWriteIntoTemporary, TestRemoveWriteIntoTemporary, TestCertainConditon) to standalone functions.
• tests/python/tir-transform/test_tir_transform_remove_undef.py
  • Converted class-based tests (BaseBeforeAfter, TestRemoveStoreUndef, TestRemoveStoreUndefExpression, TestKeepOtherCallNodes, TestRemoveLetUndef, TestRaiseErrorForUndefAsStoreIndices, TestRaiseErrorForUndefAsLoadIndices) to standalone functions.
• tests/python/tir-transform/test_tir_transform_simplify.py
  • Converted multiple class-based tests (BaseBeforeAfter, TestLoadStoreNoop, TestLoadStoreNoopAfterSimplify, TestNestedCondition, TestNestedProvableCondition, TestNestedVarCondition, TestAlteredBufferContents, TestNegationOfCondition, TestNegationOfNotEqual, TestNegationOfVarCondition, TestLiteralConstraintSplitBooleanAnd, TestLiteralConstraintSplitBooleanOr, TestProveConditionUsingLet, TestProveLetCondition, TestProveRepeatedLetCondition, TestIfThenElseExpr, TestCeilLog2Int, TestLeftCeilLog2LowerBound, TestLeftShiftLowerBound, TestLeftShiftUpperBound, TestLeftShiftOfNegativeValue, TestLeftShiftByNegativeValue, TestRemoveTransitivelyProvableCondition, TestSuppressTransitivelyProvableCondition, TestRewriteAsAndOfOrs, TestSuppressRewriteAsAndOfOrs, TestRewriteAsAndOfOrsWithTopLevelAnd, TestRewriteAsAndOfOrsWithSimplificationBetweenGroups, TestRewriteAsAndOfOrsWithSimplificationBetweenReorderedGroups, TestRewriteAsAndOfOrUsingSimplificationAcrossAnd, TestRewriteAsAndOfOrUsingSimplificationWithinOr, TestConditionalFloorMod, TestSimplifyRHSOfBooleanAndUsingLHS, TestSimplifyLHSOfBooleanAndUsingRHS, TestSimplifyRHSOfBooleanOrUsingLHS, TestSimplifyLHSOfBooleanOrUsingRHS, TestSimplifyRHSOfBooleanAndUsingLHSWithoutConst, TestSimplifyLHSOfBooleanAndUsingRHSWithoutConst, TestSimplifyRHSOfBooleanOrUsingLHSWithoutConst, TestSimplifyLHSOfBooleanOrUsingRHSWithoutConst, TestProvableConditionWithOffset, TestMostRestrictiveConditional, TestAlteredBufferContents, TestPossiblyAlteredBufferContents, TestSimplifyInputAssumption, TestNoSimplifyFromScopedInputAssumption, TestSimplifyConditionalUsingBufferValue, TestKeepExpressionSimplifyUsingBufferValue, TestSimplifyConditionalInLoopUsingBufferValue, TestSimplifyUsingBufferAssumption, TestSimplifyUsingBufferAssumptionInLoop, TestSimplifyUsingPartiallyKnownBufferConditional, TestSimplifyUsingPartiallyKnownBufferExpression, TestNoSimplificationIfPredicateNotMet, TestNoSimplifyUsingInvalidatedScopedConstraint, TestNoSimplifyUsingOverwrittenValue, TestNoSimplifyUsingLoopDependentBufferValue, TestSimplifyPriorToOverwrittenValue, TestSimplifyElementWiseUsingPreLoopBufferValue, TestSimplifyNonConditional, TestSuppressSimplifyNonConditional, TestSimplifyUsingTransitiveKnownBufferValue, TestSimplifyRampIndexBroadcastValue, TestSimplifyRampIndexRampValue, TestSimplifyUsingPartiallyProvenBufferValueGather, TestSimplifyUsingPartiallyProvenBufferValueScatter) to standalone functions.`

Activity

• The pull request was created by tqchen.
• The primary activity involves refactoring test code to remove the CompareBeforeAfter utility and update all its usages across numerous test files.
• This is a significant code cleanup and modernization effort for the testing infrastructure.

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Code Review

This pull request is a large-scale refactoring that removes the tvm.testing.CompareBeforeAfter class, which is incompatible with modern pytest versions. You've done an excellent job of converting all dependent tests to a more explicit and readable pattern using standalone functions, IRModule definitions for Before and Expected states, and direct calls to tvm.ir.assert_structural_equal. The changes are consistent across all modified files and significantly improve the test suite's maintainability. The code is cleaner and the tests are now more self-contained. Great work on this substantial refactoring effort!