More pointer finagling

Author: grynspan

Sources/Testing/Expectations/ExpectationContext.swift

@@ -450,8 +450,8 @@ extension __ExpectationContext {
   /// - Warning: This function is used to implement the `#expect()` and
   ///   `#require()` macros. Do not call it directly.
   @_disfavoredOverload
-  public mutating func callAsFunction<PFrom, PTo>(_ value: PFrom, _ id: __ExpressionID) -> PTo where PFrom: _Pointer, PTo: _Pointer {
-    self(value as PFrom?, id) as! PTo
+  public mutating func callAsFunction<P, T>(_ value: P, _ id: __ExpressionID) -> UnsafePointer<T> where P: _Pointer, P.Pointee == T {
+    self(value as P?, id)!
   }
 
   /// Convert some pointer to an immutable one and capture information about it
@@ -470,9 +470,51 @@ extension __ExpectationContext {
   /// - Warning: This function is used to implement the `#expect()` and
   ///   `#require()` macros. Do not call it directly.
   @_disfavoredOverload
-  public mutating func callAsFunction<PFrom, PTo>(_ value: PFrom?, _ id: __ExpressionID) -> PTo? where PFrom: _Pointer, PTo: _Pointer {
+  public mutating func callAsFunction<P, T>(_ value: P?, _ id: __ExpressionID) -> UnsafePointer<T>? where P: _Pointer, P.Pointee == T {
     value.flatMap { value in
-      PTo(bitPattern: Int(bitPattern: self(value, id) as PFrom))
+      UnsafePointer<T>(bitPattern: Int(bitPattern: self(value, id) as P))
+    }
+  }
+
+  /// Convert some pointer to an immutable one and capture information about it
+  /// for use if the expectation currently being evaluated fails.
+  ///
+  /// - Parameters:
+  ///   - value: The pointer to make immutable.
+  ///   - id: A value that uniquely identifies the represented expression in the
+  ///     context of the expectation currently being evaluated.
+  ///
+  /// - Returns: `value`, cast to an immutable pointer.
+  ///
+  /// This overload of `callAsFunction(_:_:)` handles the implicit conversions
+  /// between various pointer types that are normally provided by the compiler.
+  ///
+  /// - Warning: This function is used to implement the `#expect()` and
+  ///   `#require()` macros. Do not call it directly.
+  @_disfavoredOverload
+  public mutating func callAsFunction<P>(_ value: P, _ id: __ExpressionID) -> UnsafeRawPointer where P: _Pointer {
+    self(value as P?, id)!
+  }
+
+  /// Convert some pointer to an immutable one and capture information about it
+  /// for use if the expectation currently being evaluated fails.
+  ///
+  /// - Parameters:
+  ///   - value: The pointer to make immutable.
+  ///   - id: A value that uniquely identifies the represented expression in the
+  ///     context of the expectation currently being evaluated.
+  ///
+  /// - Returns: `value`, cast to an immutable pointer.
+  ///
+  /// This overload of `callAsFunction(_:_:)` handles the implicit conversions
+  /// between various pointer types that are normally provided by the compiler.
+  ///
+  /// - Warning: This function is used to implement the `#expect()` and
+  ///   `#require()` macros. Do not call it directly.
+  @_disfavoredOverload
+  public mutating func callAsFunction<P>(_ value: P?, _ id: __ExpressionID) -> UnsafeRawPointer? where P: _Pointer {
+    value.flatMap { value in
+      UnsafeRawPointer(bitPattern: Int(bitPattern: self(value, id) as P))
     }
   }
 }

Sources/TestingMacros/ConditionMacro.swift

@@ -160,8 +160,15 @@ extension ConditionMacro {
           expandedFunctionName = .identifier("__checkEscapedCondition")
 
         } else {
-          // BUG: We should use a unique name here. SEE: swift-syntax-#2256
-          let expressionContextName = TokenSyntax.identifier("__ec")
+          var expressionContextName = TokenSyntax.identifier("__ec")
+          let isNameUsed = originalArgumentExpr.tokens(viewMode: .sourceAccurate).lazy
+            .map(\.tokenKind)
+            .contains(expressionContextName.tokenKind)
+          if isNameUsed {
+            // BUG: We should use the unique name directly. SEE: swift-syntax-#2256
+            let uniqueName = context.makeUniqueName("")
+            expressionContextName = .identifier("\(expressionContextName)\(uniqueName)")
+          }
           let (rewrittenArgumentExpr, rewrittenNodes) = insertCalls(
             toExpressionContextNamed: expressionContextName,
             into: originalArgumentExpr,

Tests/TestingTests/MiscellaneousTests.swift

@@ -261,6 +261,11 @@ struct MultiLineSuite {
   _ = try #require(x?[...].last)
 }
 
+@Test(.hidden) func canHaveVariableNamed__ec() throws {
+  let __ec = 1
+  #expect(__ec == 1)
+}
+
 @Suite("Miscellaneous tests")
 struct MiscellaneousTests {
   @Test("Free function's name")