when:
        step.execute(work, context)
        then:
        _ * context.previousExecutionState >> Optional.of(previousExecutionState)
        1 * previousExecutionState.inputProperties >> ImmutableSortedMap.of()
        1 * previousExecutionState.inputFileProperties >> ImmutableSortedMap.of()
        1 * previousExecutionState.outputFilesProducedByWork >> previousOutputSnapshots

        }
        @SuppressWarnings("OptionalGetWithoutIsPresent")
        PreviousExecutionState previousExecutionState = context.getPreviousExecutionState().get();
        ExecutionOutputState executionOutputState = new DefaultExecutionOutputState(true, previousExecutionState.getOutputFilesProducedByWork(), previousExecutionState.getOriginMetadata(), true);

        _ * context.previousExecutionState >> Optional.of(previousExecutionState)
        _ * context.validationProblems >> ImmutableList.of(Mock(Problem))
        _ * context.previousExecutionState >> Optional.empty()
        0 * _
    }

    def "provides input file changes when history is available"() {
        def previousExecutionState = Mock(PreviousExecutionState)
        def changes = Mock(ExecutionStateChanges)

        }

        Optional<PreviousExecutionState> previousExecutionState = context.getPreviousExecutionState();
        ImmutableSortedMap<String, ValueSnapshot> previousInputPropertySnapshots = previousExecutionState
            .map(ExecutionInputState::getInputProperties)
            .orElse(ImmutableSortedMap.of());

class ExecuteStepTest extends StepSpec<ChangingOutputsContext> {
    def workspace = Mock(File)
    def previousOutputs = ImmutableSortedMap.of()
    def previousExecutionState = Stub(PreviousExecutionState) {
        getOutputFilesProducedByWork() >> previousOutputs
    }

    def step = new ExecuteStep<>(new TestBuildOperationRunner())
    def inputChanges = Mock(InputChangesInternal)

        !result.executionReasons.present

        _ * context.changes >> Optional.of(changes)
        _ * context.rebuildReasons >> ImmutableList.of()
        _ * context.previousExecutionState >> Optional.of(Stub(PreviousExecutionState) {
            getOutputFilesProducedByWork() >> ImmutableSortedMap.of()
            getOriginMetadata() >> delegateOriginMetadata
        })
        0 * _
    }

import org.gradle.internal.execution.UnitOfWork;
import org.gradle.internal.execution.history.OverlappingOutputDetector;
import org.gradle.internal.execution.history.OverlappingOutputs;
import org.gradle.internal.execution.history.PreviousExecutionState;
import org.gradle.internal.hash.ClassLoaderHierarchyHasher;
import org.gradle.internal.operations.BuildOperationRunner;
import org.gradle.internal.snapshot.FileSystemSnapshot;

import javax.annotation.Nullable;

import org.gradle.internal.execution.history.PreviousExecutionState;
import org.gradle.internal.service.scopes.Scope;
import org.gradle.internal.service.scopes.ServiceScope;

@ServiceScope(Scope.Global.class)
public interface ExecutionStateChangeDetector {
    int MAX_OUT_OF_DATE_MESSAGES = 3;

    ExecutionStateChanges detectChanges(
        Describable executable,
        PreviousExecutionState lastExecution,

import org.gradle.internal.execution.ExecutionEngine.Execution;
import org.gradle.internal.execution.ExecutionEngine.ExecutionOutcome;
import org.gradle.internal.execution.UnitOfWork;
import org.gradle.internal.execution.history.PreviousExecutionState;
import org.gradle.internal.execution.history.changes.InputChangesInternal;
import org.gradle.internal.operations.BuildOperationContext;
import org.gradle.internal.operations.BuildOperationDescriptor;

import org.gradle.api.Describable;
import org.gradle.internal.Cast;
import org.gradle.internal.execution.history.BeforeExecutionState;
import org.gradle.internal.execution.history.PreviousExecutionState;
import org.gradle.internal.snapshot.FileSystemSnapshot;
import org.gradle.internal.snapshot.impl.ClassImplementationSnapshot;
import org.gradle.internal.snapshot.impl.ImplementationSnapshot;