Analyze local Invoke-Command regions (#109)

* Analyze local Invoke-Command regions

* Make PowerShell oracle cross-platform

Author: Aaronontheweb

IMPLEMENTATION_PLAN.md

@@ -402,8 +402,13 @@ priorities.
       pin current-scope mutation, empty input, explicit input, phase order, and
       the differing no-input behavior of the two cmdlets. Ordinary assignment
       state transfer remains an atomic task 7.5b follow-up; task 7.5b is not
-      complete. Continue with in-process `Invoke-Command`; child
-      process/runspace jobs and parallel
+      complete. In-process `Invoke-Command` now distinguishes default child
+      variable/command scope from `-NoNewScope` current-scope flow while
+      propagating shared location and retaining synchronous/once region facts.
+      Pipelines with any supported synchronous execution region plus another
+      stateful stage withhold body facts that downstream initialization or
+      per-object interleaving can invalidate.
+      Child process/runspace jobs and parallel
       blocks; deferred breakpoint/event/completion actions; then unknown
       receiver and nested/adversarial matrices. Preserve script blocks proved
       to be data as opaque values, expose ambiguous bodies with incomplete

src/ShellSyntaxTree/Internal/Pwsh/Parsing/PwshForEachValueAnalysis.cs

@@ -988,7 +988,7 @@ private readonly Dictionary<Clause, IReadOnlyList<ExecutionRegionSyntax>>
     private long _locationStateMutationCount;
     private long _childScopeEscapeRiskCount;
     private bool _pipelineStageMayReceiveInput;
-    private bool _pipelineCallbacksMayInterleave;
+    private bool _pipelineStageEffectsMayReachRegionBodies;
 
     private PwshForEachValueAnalyzer(
         PwshParserOptions options,
@@ -1220,6 +1220,15 @@ flow.OnFailure is AnalysisContext failure
                 flow);
         }
 
+        if (binding.ParameterSet == PwshExecutionRegionParameterSet.InvokeInProcess)
+        {
+            return AnalyzeInProcessInvokeCommand(
+                binding,
+                regions[0],
+                regionInput,
+                flow);
+        }
+
         var executionRegionEffectCount = _executionRegionEffectCount;
         var nonRegionStateMutationCount = _nonRegionStateMutationCount;
         var bodyFlow = AnalyzeExecutionRegionBody(regions[0].Body, regionInput);
@@ -1230,6 +1239,48 @@ flow.OnFailure is AnalysisContext failure
             : flow;
     }
 
+    private PwshFlowResult AnalyzeInProcessInvokeCommand(
+        PwshExecutionRegionBindingResult binding,
+        ExecutionRegionSyntax region,
+        AnalysisContext input,
+        PwshFlowResult fallback)
+    {
+        var executionRegionEffectCount = _executionRegionEffectCount;
+        var nonRegionStateMutationCount = _nonRegionStateMutationCount;
+        var locationStateMutationCount = _locationStateMutationCount;
+        var childScopeEscapeRiskCount = _childScopeEscapeRiskCount;
+        var body = AnalyzeExecutionRegionBody(region.Body, input);
+        var locationMutated = _locationStateMutationCount > locationStateMutationCount;
+        var childScopeMayEscape =
+            _childScopeEscapeRiskCount > childScopeEscapeRiskCount;
+        _executionRegionEffectCount = executionRegionEffectCount + 1;
+        _nonRegionStateMutationCount = nonRegionStateMutationCount;
+
+        if (binding.HasNoNewScope)
+        {
+            return body.JoinedState is AnalysisContext bodyExit
+                ? PwshFlowResult.Both(bodyExit)
+                : fallback;
+        }
+
+        _childScopeEscapeRiskCount = childScopeEscapeRiskCount +
+            (childScopeMayEscape ? 1 : 0);
+        var restoredExit = AnalysisContext.JoinNullable(
+            RestoreChildScopeExit(
+                body.OnSuccess,
+                input,
+                locationMutated,
+                childScopeMayEscape),
+            RestoreChildScopeExit(
+                body.OnFailure,
+                input,
+                locationMutated,
+                childScopeMayEscape));
+        return restoredExit is AnalysisContext joined
+            ? PwshFlowResult.Both(joined)
+            : fallback;
+    }
+
     private PwshFlowResult AnalyzePipelineCallbackRegions(
         PwshExecutionRegionBindingResult binding,
         IReadOnlyList<ExecutionRegionSyntax> regions,
@@ -1362,7 +1413,7 @@ private PwshFlowResult AnalyzeExecutionRegionBody(
     {
         var enclosingStageMayReceiveInput = _pipelineStageMayReceiveInput;
         _pipelineStageMayReceiveInput = false;
-        var bodyInput = _pipelineCallbacksMayInterleave
+        var bodyInput = _pipelineStageEffectsMayReachRegionBodies
             ? input.Invalidate(unknownCwd: true)
             : input;
         var flow = AnalyzeBlock(body, bodyInput);
@@ -1445,6 +1496,7 @@ private static bool IsSupportedSynchronousReceiver(
         binding.Status == PwshExecutionRegionBindingStatus.ProvedExecution &&
         (binding.ParameterSet is PwshExecutionRegionParameterSet.MeasureExpression or
             PwshExecutionRegionParameterSet.TraceExpression or
+            PwshExecutionRegionParameterSet.InvokeInProcess or
             PwshExecutionRegionParameterSet.ForEachScriptBlock or
             PwshExecutionRegionParameterSet.WhereScriptBlock) &&
         AllBindingsAreCompleteAndSynchronous(binding.Bindings);
@@ -1606,8 +1658,10 @@ private PwshFlowResult AnalyzeList(CommandListSyntax list, AnalysisContext input
     private PwshFlowResult AnalyzePipeline(PipelineSyntax pipeline, AnalysisContext input)
     {
         var stageInput = input;
-        var enclosingCallbacksMayInterleave = _pipelineCallbacksMayInterleave;
-        _pipelineCallbacksMayInterleave |= PipelineCallbacksMayInterleave(pipeline);
+        var enclosingStageEffectsMayReachBodies =
+            _pipelineStageEffectsMayReachRegionBodies;
+        _pipelineStageEffectsMayReachRegionBodies |=
+            PipelineStageEffectsMayReachRegionBodies(pipeline);
         try
         {
             for (var stageIndex = 0; stageIndex < pipeline.Stages.Count; stageIndex++)
@@ -1644,35 +1698,43 @@ private PwshFlowResult AnalyzePipeline(PipelineSyntax pipeline, AnalysisContext
         }
         finally
         {
-            _pipelineCallbacksMayInterleave = enclosingCallbacksMayInterleave;
+            _pipelineStageEffectsMayReachRegionBodies =
+                enclosingStageEffectsMayReachBodies;
         }
     }
 
-    private static bool PipelineCallbacksMayInterleave(PipelineSyntax pipeline)
+    private static bool PipelineStageEffectsMayReachRegionBodies(PipelineSyntax pipeline)
     {
-        var hasCallback = false;
+        var hasPipelineSensitiveRegion = false;
         var statefulStageCount = 0;
         for (var index = 0; index < pipeline.Stages.Count; index++)
         {
             var stage = pipeline.Stages[index];
-            hasCallback |= ContainsPipelineCallback(stage);
+            hasPipelineSensitiveRegion |= ContainsPipelineSensitiveExecutionRegion(stage);
             if (MayMutatePipelineState(stage))
             {
                 statefulStageCount++;
             }
         }
 
-        return hasCallback && statefulStageCount > 1;
+        return hasPipelineSensitiveRegion && statefulStageCount > 1;
     }
 
-    private static bool ContainsPipelineCallback(ShellSyntaxNode node) =>
+    private static bool ContainsPipelineSensitiveExecutionRegion(ShellSyntaxNode node) =>
         node switch
         {
-            SimpleCommandSyntax simple => IsPipelineCallback(simple),
-            ShellBlockSyntax block => BlockContains(block, ContainsPipelineCallback),
-            GroupSyntax group => ContainsPipelineCallback(group.Body),
-            CommandListSyntax list => ListContains(list, ContainsPipelineCallback),
-            PipelineSyntax pipeline => PipelineContains(pipeline, ContainsPipelineCallback),
+            SimpleCommandSyntax simple => IsPipelineSensitiveExecutionRegionHost(simple),
+            ShellBlockSyntax block => BlockContains(
+                block,
+                ContainsPipelineSensitiveExecutionRegion),
+            GroupSyntax group => ContainsPipelineSensitiveExecutionRegion(group.Body),
+            CommandListSyntax list => ListContains(
+                list,
+                ContainsPipelineSensitiveExecutionRegion),
+            PipelineSyntax pipeline => PipelineContains(
+                pipeline,
+                ContainsPipelineSensitiveExecutionRegion),
+            ExecutionRegionSyntax => true,
             _ => false,
         };
 
@@ -1690,14 +1752,17 @@ private static bool MayMutatePipelineState(ShellSyntaxNode node) =>
             _ => false,
         };
 
-    private static bool IsPipelineCallback(SimpleCommandSyntax simple)
+    private static bool IsPipelineSensitiveExecutionRegionHost(SimpleCommandSyntax simple)
     {
         var binding = PwshExecutionRegionBindingCatalog.Bind(
             simple.Clause,
             commandIdentityProven: true);
         return binding.Status == PwshExecutionRegionBindingStatus.ProvedExecution &&
             binding.ParameterSet is PwshExecutionRegionParameterSet.ForEachScriptBlock or
-                PwshExecutionRegionParameterSet.WhereScriptBlock;
+                PwshExecutionRegionParameterSet.WhereScriptBlock or
+                PwshExecutionRegionParameterSet.InvokeInProcess or
+                PwshExecutionRegionParameterSet.MeasureExpression or
+                PwshExecutionRegionParameterSet.TraceExpression;
     }
 
     private static bool SimpleMayMutatePipelineState(SimpleCommandSyntax simple)
@@ -1818,19 +1883,19 @@ private PwshFlowResult AnalyzeExecutionRegion(
         }
 
         return new PwshFlowResult(
-            RestoreDirectCallExit(
+            RestoreChildScopeExit(
                 body.OnSuccess,
                 input,
                 locationMutated,
                 childScopeMayEscape),
-            RestoreDirectCallExit(
+            RestoreChildScopeExit(
                 body.OnFailure,
                 input,
                 locationMutated,
                 childScopeMayEscape));
     }
 
-    private static AnalysisContext? RestoreDirectCallExit(
+    private static AnalysisContext? RestoreChildScopeExit(
         AnalysisContext? bodyExit,
         AnalysisContext input,
         bool locationMutated,

src/ShellSyntaxTree/Internal/Pwsh/Verbs/PwshExecutionRegionBindingCatalog.cs

@@ -92,6 +92,8 @@ internal sealed record PwshExecutionRegionBindingResult
 
     internal bool HasExplicitInputObject { get; init; }
 
+    internal bool HasNoNewScope { get; init; }
+
     internal IReadOnlyList<PwshExecutionRegionBinding> Bindings { get; init; } =
         Array.Empty<PwshExecutionRegionBinding>();
 }
@@ -443,6 +445,8 @@ private static PwshExecutionRegionBindingResult BindReceiver(
             ParameterSet = parameterSet,
             CanonicalCommandName = canonicalName,
             HasExplicitInputObject = arguments.HasNamed("InputObject"),
+            HasNoNewScope = receiver == PwshExecutionRegionReceiver.InvokeCommand &&
+                arguments.IsSwitchEnabled("NoNewScope"),
             Bindings = bindings.OrderBy(binding => binding.HostClauseElementIndex).ToArray(),
         };
     }
@@ -1572,6 +1576,33 @@ internal void AddNamedParameter(string name)
 
         internal bool HasNamed(string name) => NamedParameters.Contains(name);
 
+        internal bool IsSwitchEnabled(string name)
+        {
+            if (!HasNamed(name))
+            {
+                return false;
+            }
+
+            foreach (var argument in NamedArguments)
+            {
+                if (!string.Equals(
+                        argument.ParameterName,
+                        name,
+                        StringComparison.OrdinalIgnoreCase))
+                {
+                    continue;
+                }
+
+                return string.Equals(
+                        argument.Value,
+                        "$true",
+                        StringComparison.OrdinalIgnoreCase) ||
+                    argument.Value == "1";
+            }
+
+            return true;
+        }
+
         internal bool HasAnyNamed(params string[] names) => names.Any(HasNamed);
 
         internal int CountNamed(params string[] names) => names.Count(HasNamed);

tests/ShellSyntaxTree.Tests/Parsing/PwshExecutionRegionBindingCatalogTests.cs

@@ -297,6 +297,20 @@ public void Invoke_command_distinguishes_in_process_and_remote_parameter_sets()
 
         Assert.Equal(PwshExecutionRegionParameterSet.InvokeInProcess, local.ParameterSet);
         Assert.True(Assert.Single(local.Bindings).IsComplete);
+        Assert.True(local.HasNoNewScope);
+        var positionalLocal = Bind("Invoke-Command { Get-Date }");
+        Assert.Equal(
+            PwshExecutionRegionParameterSet.InvokeInProcess,
+            positionalLocal.ParameterSet);
+        Assert.False(positionalLocal.HasNoNewScope);
+        Assert.False(Bind(
+            "Invoke-Command -NoNewScope:$false { Get-Date }").HasNoNewScope);
+        Assert.True(Bind(
+            "Invoke-Command -NoNewScope:$true { Get-Date }").HasNoNewScope);
+        Assert.False(Bind(
+            "Invoke-Command -NoNewScope:0 { Get-Date }").HasNoNewScope);
+        Assert.True(Bind(
+            "Invoke-Command -NoNewScope:1 { Get-Date }").HasNoNewScope);
         Assert.Equal(PwshExecutionRegionParameterSet.InvokeRemote, remote.ParameterSet);
         var remoteBinding = Assert.Single(remote.Bindings);
         Assert.Equal(ExecutionRegionTiming.Unknown, remoteBinding.Timing);