C#: Add types for pattern expressions.

Author: michaelnebel

csharp/extractor/Semmle.Extraction.CSharp/CodeAnalysisExtensions/SymbolExtensions.cs

@@ -785,6 +785,18 @@ public static AnnotatedTypeSymbol GetType(this Context cx, Microsoft.CodeAnalysi
             return new AnnotatedTypeSymbol(info.Type.DisambiguateType(), info.Nullability.Annotation);
         }
 
+        /// <summary>
+        /// Gets the converted type of a syntax node, or default if it could not be determined.
+        /// </summary>
+        /// <param name="cx">Extractor context.</param>
+        /// <param name="node">The syntax node to determine the converted type for.</param>
+        /// <returns>The converted type symbol of the node, or default.</returns>
+        public static AnnotatedTypeSymbol GetConvertedType(this Context cx, Microsoft.CodeAnalysis.CSharp.CSharpSyntaxNode node)
+        {
+            var info = GetTypeInfo(cx, node);
+            return new AnnotatedTypeSymbol(info.ConvertedType.DisambiguateType(), info.Nullability.Annotation);
+        }
+
         /// <summary>
         /// Gets the annotated type arguments of an INamedTypeSymbol.
         /// This has not yet been exposed on the public API.

csharp/extractor/Semmle.Extraction.CSharp/Entities/Expressions/Patterns/BinaryPattern.cs

@@ -8,7 +8,7 @@ namespace Semmle.Extraction.CSharp.Entities.Expressions
     internal class BinaryPattern : Expression
     {
         public BinaryPattern(Context cx, BinaryPatternSyntax syntax, IExpressionParentEntity parent, int child) :
-            base(new ExpressionInfo(cx, null, cx.CreateLocation(syntax.GetLocation()), GetKind(syntax.OperatorToken, syntax), parent, child, isCompilerGenerated: false, null))
+            base(new ExpressionInfo(cx, cx.GetConvertedType(syntax), cx.CreateLocation(syntax.GetLocation()), GetKind(syntax.OperatorToken, syntax), parent, child, isCompilerGenerated: false, null))
         {
             Pattern.Create(cx, syntax.Left, this, 0);
             Pattern.Create(cx, syntax.Right, this, 1);
@@ -24,4 +24,4 @@ private static ExprKind GetKind(SyntaxToken operatorToken, BinaryPatternSyntax s
             };
         }
     }
-}
+}

csharp/extractor/Semmle.Extraction.CSharp/Entities/Expressions/Patterns/ListPattern.cs

@@ -7,9 +7,9 @@ namespace Semmle.Extraction.CSharp.Entities.Expressions
     internal class ListPattern : Expression
     {
         internal ListPattern(Context cx, ListPatternSyntax syntax, IExpressionParentEntity parent, int child) :
-            base(new ExpressionInfo(cx, null, cx.CreateLocation(syntax.GetLocation()), ExprKind.LIST_PATTERN, parent, child, isCompilerGenerated: false, null))
+            base(new ExpressionInfo(cx, cx.GetConvertedType(syntax), cx.CreateLocation(syntax.GetLocation()), ExprKind.LIST_PATTERN, parent, child, isCompilerGenerated: false, null))
         {
             syntax.Patterns.ForEach((p, i) => Pattern.Create(cx, p, this, i));
         }
     }
-}
+}

csharp/extractor/Semmle.Extraction.CSharp/Entities/Expressions/Patterns/RecursivePattern.cs

@@ -15,7 +15,7 @@ internal class RecursivePattern : Expression
         /// <param name="parent">The parent pattern/expression.</param>
         /// <param name="child">The child index of this pattern.</param>
         public RecursivePattern(Context cx, RecursivePatternSyntax syntax, IExpressionParentEntity parent, int child) :
-            base(new ExpressionInfo(cx, null, cx.CreateLocation(syntax.GetLocation()), ExprKind.RECURSIVE_PATTERN, parent, child, isCompilerGenerated: false, null))
+            base(new ExpressionInfo(cx, cx.GetConvertedType(syntax), cx.CreateLocation(syntax.GetLocation()), ExprKind.RECURSIVE_PATTERN, parent, child, isCompilerGenerated: false, null))
         {
             // Extract the type access
             if (syntax.Type is TypeSyntax t)

csharp/extractor/Semmle.Extraction.CSharp/Entities/Expressions/Patterns/RelationalPattern.cs

@@ -8,7 +8,7 @@ namespace Semmle.Extraction.CSharp.Entities.Expressions
     internal class RelationalPattern : Expression
     {
         public RelationalPattern(Context cx, RelationalPatternSyntax syntax, IExpressionParentEntity parent, int child) :
-             base(new ExpressionInfo(cx, null, cx.CreateLocation(syntax.GetLocation()), GetKind(syntax.OperatorToken), parent, child, isCompilerGenerated: false, null))
+             base(new ExpressionInfo(cx, cx.GetConvertedType(syntax), cx.CreateLocation(syntax.GetLocation()), GetKind(syntax.OperatorToken), parent, child, isCompilerGenerated: false, null))
         {
             Expression.Create(cx, syntax.Expression, this, 0);
         }

csharp/extractor/Semmle.Extraction.CSharp/Entities/Expressions/Patterns/SlicePattern.cs

@@ -6,12 +6,12 @@ namespace Semmle.Extraction.CSharp.Entities.Expressions
     internal class SlicePattern : Expression
     {
         public SlicePattern(Context cx, SlicePatternSyntax syntax, IExpressionParentEntity parent, int child) :
-            base(new ExpressionInfo(cx, null, cx.CreateLocation(syntax.GetLocation()), ExprKind.SLICE_PATTERN, parent, child, isCompilerGenerated: false, null))
+            base(new ExpressionInfo(cx, cx.GetConvertedType(syntax), cx.CreateLocation(syntax.GetLocation()), ExprKind.SLICE_PATTERN, parent, child, isCompilerGenerated: false, null))
         {
             if (syntax.Pattern is not null)
             {
                 Pattern.Create(cx, syntax.Pattern, this, 0);
             }
         }
     }
-}
+}

csharp/extractor/Semmle.Extraction.CSharp/Entities/Expressions/Patterns/UnaryPattern.cs

@@ -6,9 +6,9 @@ namespace Semmle.Extraction.CSharp.Entities.Expressions
     internal class UnaryPattern : Expression
     {
         public UnaryPattern(Context cx, UnaryPatternSyntax syntax, IExpressionParentEntity parent, int child) :
-            base(new ExpressionInfo(cx, null, cx.CreateLocation(syntax.GetLocation()), ExprKind.NOT_PATTERN, parent, child, isCompilerGenerated: false, null))
+            base(new ExpressionInfo(cx, cx.GetConvertedType(syntax), cx.CreateLocation(syntax.GetLocation()), ExprKind.NOT_PATTERN, parent, child, isCompilerGenerated: false, null))
         {
             Pattern.Create(cx, syntax.Pattern, this, 0);
         }
     }
-}
+}