Fix TypeName.GetReflectionType() to work when the TypeName instance represents a generic type definition within a GenericTypeName (#24985)

2026-06-08 12:12:50 +00:00 · 2025-03-17 15:40:25 -07:00
parent 490d3a8c20
commit ef64132f0a
3 changed files with 109 additions and 12 deletions
@@ -1487,7 +1487,7 @@ namespace System.Management.Automation.Language
                rBracketToken = null;
            }

-            var openGenericType = new TypeName(genericTypeName.Extent, genericTypeName.Text);
+            var openGenericType = new TypeName(genericTypeName.Extent, genericTypeName.Text, genericArguments.Count);
            var result = new GenericTypeName(
                ExtentOf(genericTypeName.Extent, ExtentFromFirstOf(rBracketToken, genericArguments.LastOrDefault(), firstToken)),
                openGenericType,
@@ -7263,7 +7263,7 @@ namespace System.Management.Automation.Language
                        FunctionName.Extent,
                        new TypeName(
                            FunctionName.Extent,
-                            typeof(System.Management.Automation.Language.DynamicKeyword).FullName)),
+                            typeof(DynamicKeyword).FullName)),
                    new StringConstantExpressionAst(
                        FunctionName.Extent,
                        "GetKeyword",
@@ -8424,9 +8424,11 @@ namespace System.Management.Automation.Language
    /// </summary>
    public sealed class TypeName : ITypeName, ISupportsTypeCaching
    {
-        internal readonly string _name;
-        internal Type _type;
-        internal readonly IScriptExtent _extent;
+        private readonly string _name;
+        private readonly IScriptExtent _extent;
+        private readonly int _genericArgumentCount;
+        private Type _type;
+
        internal TypeDefinitionAst _typeDefinitionAst;

        /// <summary>
@@ -8485,6 +8487,23 @@ namespace System.Management.Automation.Language
            AssemblyName = assembly;
        }

+        /// <summary>
+        /// Construct a typename that represents a generic type definition.
+        /// </summary>
+        /// <param name="extent">The extent of the typename.</param>
+        /// <param name="name">The name of the type.</param>
+        /// <param name="genericArgumentCount">The number of generic arguments.</param>
+        internal TypeName(IScriptExtent extent, string name, int genericArgumentCount)
+            : this(extent, name)
+        {
+            ArgumentOutOfRangeException.ThrowIfLessThan(genericArgumentCount, 0);
+
+            if (genericArgumentCount > 0 && !_name.Contains('`'))
+            {
+                _genericArgumentCount = genericArgumentCount;
+            }
+        }
+
        /// <summary>
        /// Returns the full name of the type.
        /// </summary>
@@ -8561,8 +8580,25 @@ namespace System.Management.Automation.Language
        {
            if (_type == null)
            {
-                Exception e;
-                Type type = _typeDefinitionAst != null ? _typeDefinitionAst.Type : TypeResolver.ResolveTypeName(this, out e);
+                Type type = _typeDefinitionAst != null ? _typeDefinitionAst.Type : TypeResolver.ResolveTypeName(this, out _);
+
+                if (type is null && _genericArgumentCount > 0)
+                {
+                    // We try an alternate name only if it failed to resolve with the original name.
+                    // This is because for a generic type like `System.Tuple<type1, type2>`, the original name `System.Tuple`
+                    // can be resolved and hence `genericTypeName.TypeName.GetReflectionType()` in that case has always been
+                    // returning the type `System.Tuple`. If we change to directly use the alternate name for resolution, the
+                    // return value will become 'System.Tuple`1' in that case, and that's a breaking change.
+                    TypeName newTypeName = new(
+                        _extent,
+                        string.Create(CultureInfo.InvariantCulture, $"{_name}`{_genericArgumentCount}"))
+                    {
+                        AssemblyName = AssemblyName
+                    };
+
+                    type = TypeResolver.ResolveTypeName(newTypeName, out _);
+                }
+
                if (type != null)
                {
                    try
@@ -8597,7 +8633,11 @@ namespace System.Management.Automation.Language
            var result = GetReflectionType();
            if (result == null || !typeof(Attribute).IsAssignableFrom(result))
            {
-                var attrTypeName = new TypeName(_extent, FullName + "Attribute");
+                TypeName attrTypeName = new(_extent, $"{_name}Attribute", _genericArgumentCount)
+                {
+                    AssemblyName = AssemblyName
+                };
+
                result = attrTypeName.GetReflectionType();
                if (result != null && !typeof(Attribute).IsAssignableFrom(result))
                {
@@ -8890,8 +8930,13 @@ namespace System.Management.Automation.Language
            {
                if (!TypeName.FullName.Contains('`'))
                {
-                    var newTypeName = new TypeName(Extent,
-                        string.Create(CultureInfo.InvariantCulture, $"{TypeName.FullName}`{GenericArguments.Count}"));
+                    TypeName newTypeName = new(
+                        Extent,
+                        string.Create(CultureInfo.InvariantCulture, $"{TypeName.Name}`{GenericArguments.Count}"))
+                    {
+                        AssemblyName = TypeName.AssemblyName
+                    };
+
                    generic = newTypeName.GetReflectionType();
                }
            }
@@ -8917,8 +8962,13 @@ namespace System.Management.Automation.Language
                {
                    if (!TypeName.FullName.Contains('`'))
                    {
-                        var newTypeName = new TypeName(Extent,
-                            string.Create(CultureInfo.InvariantCulture, $"{TypeName.FullName}Attribute`{GenericArguments.Count}"));
+                        TypeName newTypeName = new(
+                            Extent,
+                            string.Create(CultureInfo.InvariantCulture, $"{TypeName.Name}Attribute`{GenericArguments.Count}"))
+                        {
+                            AssemblyName = TypeName.AssemblyName
+                        };
+
                        generic = newTypeName.GetReflectionType();
                    }
                }
@@ -683,6 +683,53 @@ Describe "Additional tests" -Tag CI {
        $result.EndBlock.Statements[0].PipelineElements[0].Expression.TypeName.FullName | Should -Be 'System.Tuple[System.String[],System.Int32[]]'
    }

+    It "Should correctly set the cached type for 'GenericTypeName.TypeName' as needed when the generic type is found in cache" {
+        $tks = $null
+        $ers = $null
+        $Script = '[System.Collections.Generic.List[string]]'
+
+        ## See https://github.com/PowerShell/PowerShell/issues/24982 for details about the issue.
+        $result = [System.Management.Automation.Language.Parser]::ParseInput($Script, [ref]$tks, [ref]$ers)
+        $typeExpr = $result.EndBlock.Statements[0].PipelineElements[0].Expression
+        $typeExpr.TypeName.FullName | Should -Be 'System.Collections.Generic.List[string]'
+        $typeExpr.TypeName.TypeName.FullName | Should -Be 'System.Collections.Generic.List'
+        $typeExpr.TypeName.TypeName.GetReflectionType() | Should -Not -BeNullOrEmpty
+        $typeExpr.TypeName.TypeName.GetReflectionType().FullName | Should -Be 'System.Collections.Generic.List`1'
+
+        $result2 = [System.Management.Automation.Language.Parser]::ParseInput($Script, [ref]$tks, [ref]$ers)
+        $typeExpr2 = $result2.EndBlock.Statements[0].PipelineElements[0].Expression
+        $typeExpr2.TypeName.FullName | Should -Be 'System.Collections.Generic.List[string]'
+        $typeExpr2.TypeName.TypeName.FullName | Should -Be 'System.Collections.Generic.List'
+        $typeExpr2.TypeName.TypeName.GetReflectionType() | Should -Not -BeNullOrEmpty
+        $typeExpr2.TypeName.TypeName.GetReflectionType().FullName | Should -Be 'System.Collections.Generic.List`1'
+
+        $Script = '[System.Tuple[System.String[],System.Int32[]]]'
+        $result3 = [System.Management.Automation.Language.Parser]::ParseInput($Script, [ref]$tks, [ref]$ers)
+        $result3.EndBlock.Statements[0].PipelineElements[0].Expression.TypeName.TypeName.GetReflectionType().FullName | Should -Be 'System.Tuple'
+
+        ## Generic type with assembly name can be resolved.
+        [System.Collections.Generic.List[string], System.Private.CoreLib].FullName | Should -BeLike 'System.Collections.Generic.List``1`[`[System.String, *`]`]'
+
+        $Script = '[System.Collections.Generic.List[string], System.Private.CoreLib]'
+        $result4 = [System.Management.Automation.Language.Parser]::ParseInput($Script, [ref]$tks, [ref]$ers)
+        $typeExpr4 = $result4.EndBlock.Statements[0].PipelineElements[0].Expression
+        $typeExpr4.TypeName.FullName | Should -Be 'System.Collections.Generic.List[string],System.Private.CoreLib'
+        $typeExpr4.TypeName.TypeName.FullName | Should -Be 'System.Collections.Generic.List,System.Private.CoreLib'
+        $typeExpr4.TypeName.TypeName.GetReflectionType() | Should -Not -BeNullOrEmpty
+        $typeExpr4.TypeName.TypeName.GetReflectionType().FullName | Should -Be 'System.Collections.Generic.List`1'
+
+        ## Generic type with '`<n>' in name can be resolved.
+        [System.Collections.Generic.List`1[string]].FullName | Should -BeLike 'System.Collections.Generic.List``1`[`[System.String, *`]`]'
+
+        $Script = '[System.Collections.Generic.List`1[string]]'
+        $result5 = [System.Management.Automation.Language.Parser]::ParseInput($Script, [ref]$tks, [ref]$ers)
+        $typeExpr5 = $result5.EndBlock.Statements[0].PipelineElements[0].Expression
+        $typeExpr5.TypeName.FullName | Should -Be 'System.Collections.Generic.List`1[string]'
+        $typeExpr5.TypeName.TypeName.FullName | Should -Be 'System.Collections.Generic.List`1'
+        $typeExpr5.TypeName.TypeName.GetReflectionType() | Should -Not -BeNullOrEmpty
+        $typeExpr5.TypeName.TypeName.GetReflectionType().FullName | Should -Be 'System.Collections.Generic.List`1'
+    }
+
    It "Should get correct offsets for number constant parsing error" {
        $tks = $null
        $ers = $null