[Swiftify] Copy doc comment from clang node

lib/ClangImporter/ImportDecl.cpp

@@ -9281,10 +9281,28 @@ void ClangImporter::Implementation::swiftify(FuncDecl *MappedDecl) {
       attachMacro = true;
     printer.printAvailability();
     printer.printTypeMapping(typeMapping);
+
   }
 
-  if (attachMacro)
-    importNontrivialAttribute(MappedDecl, MacroString);
+  if (attachMacro) {
+    if (clang::RawComment *raw =
+            getClangASTContext().getRawCommentForDeclNoCache(ClangDecl)) {
+      // swift::RawDocCommentAttr doesn't contain its text directly, but instead
+      // references the source range of the parsed comment. Instead of creating
+      // a new source file just to parse the doc comment, we can add the
+      // comment to the macro invocation attribute, which the macro has access
+      // to. Waiting until we know that the macro will be attached before
+      // emitting the comment to the string, despite the comment occurring
+      // first, avoids copying a bunch of potentially long comments for nodes
+      // that don't end up with wrappers.
+      auto commentString =
+          raw->getRawText(getClangASTContext().getSourceManager());
+      importNontrivialAttribute(MappedDecl,
+                                (commentString + "\n" + MacroString).str());
+    } else {
+      importNontrivialAttribute(MappedDecl, MacroString);
+    }
+  }
 }
 
 static bool isUsingMacroName(clang::SourceManager &SM,

lib/Macros/Sources/SwiftMacros/SwiftifyImportMacro.swift

@@ -1550,6 +1550,7 @@ public struct SwiftifyImportMacro: PeerMacro {
             + availabilityAttr
             + lifetimeAttrs
             + disfavoredOverload)
+        .with(\.leadingTrivia, node.leadingTrivia + .docLineComment("/// This is an auto-generated wrapper for safer interop\n"))
       return [DeclSyntax(newFunc)]
     } catch let error as DiagnosticError {
       context.diagnose(

test/Interop/C/swiftify-import/Inputs/comments.h

@@ -0,0 +1,30 @@
+#pragma once
+
+#define __counted_by(x) __attribute__((__counted_by__(x)))
+
+void begin();
+
+// line comment
+void lineComment(int len, int * __counted_by(len) p);
+
+/// line doc comment
+/// 
+/// Here's a more complete description.
+///
+/// @param len the buffer length
+/// @param p the buffer
+void lineDocComment(int len, int * __counted_by(len) p);
+
+/*
+ block comment
+ */
+void blockComment(int len, int * __counted_by(len) p);
+
+/**
+ * block doc comment
+ * 
+ * NB: it's very important to pass the correct length to this function
+ * @param len don't mess this one up
+ * @param p   some integers to play with
+ */
+void blockDocComment(int len, int * __counted_by(len) p);

test/Interop/C/swiftify-import/Inputs/module.modulemap

@@ -14,3 +14,7 @@ module SizedByNoEscapeClang {
     header "sized-by-noescape.h"
     export *
 }
+module CommentsClang {
+    header "comments.h"
+    export *
+}

test/Interop/C/swiftify-import/comments.swift

@@ -0,0 +1,52 @@
+// REQUIRES: swift_feature_SafeInteropWrappers
+
+// RUN: %target-swift-ide-test -print-module -module-to-print=CommentsClang -plugin-path %swift-plugin-dir -I %S/Inputs -source-filename=x -enable-experimental-feature SafeInteropWrappers | %FileCheck %s --strict-whitespace --match-full-lines
+
+// Check that doc comments are carried over from clang to the safe macro expansion.
+
+// CHECK:func begin()
+// CHECK-NEXT:func lineComment(_ len: Int32, _ p: UnsafeMutablePointer<Int32>!)
+
+// CHECK-NEXT:/// line doc comment
+// CHECK-NEXT:/// 
+// CHECK-NEXT:/// Here's a more complete description.
+// CHECK-NEXT:///
+// CHECK-NEXT:/// @param len the buffer length
+// CHECK-NEXT:/// @param p the buffer
+// CHECK-NEXT:func lineDocComment(_ len: Int32, _ p: UnsafeMutablePointer<Int32>!)
+
+// CHECK-NEXT:func blockComment(_ len: Int32, _ p: UnsafeMutablePointer<Int32>!)
+
+// CHECK-NEXT:/**
+// CHECK-NEXT: * block doc comment
+// CHECK-NEXT: * 
+// CHECK-NEXT: * NB: it's very important to pass the correct length to this function
+// CHECK-NEXT: * @param len don't mess this one up
+// CHECK-NEXT: * @param p   some integers to play with
+// CHECK-NEXT: */
+// CHECK-NEXT:func blockDocComment(_ len: Int32, _ p: UnsafeMutablePointer<Int32>!)
+
+// CHECK-NEXT:/// This is an auto-generated wrapper for safer interop
+// CHECK-NEXT:@_alwaysEmitIntoClient public func blockComment(_ p: UnsafeMutableBufferPointer<Int32>)
+
+// CHECK-NEXT:/**
+// CHECK-NEXT: * block doc comment
+// CHECK-NEXT: * 
+// CHECK-NEXT: * NB: it's very important to pass the correct length to this function
+// CHECK-NEXT: * @param len don't mess this one up
+// CHECK-NEXT: * @param p   some integers to play with
+// CHECK-NEXT: */
+// CHECK-NEXT:/// This is an auto-generated wrapper for safer interop
+// CHECK-NEXT:@_alwaysEmitIntoClient public func blockDocComment(_ p: UnsafeMutableBufferPointer<Int32>)
+
+// CHECK-NEXT:/// This is an auto-generated wrapper for safer interop
+// CHECK-NEXT:@_alwaysEmitIntoClient public func lineComment(_ p: UnsafeMutableBufferPointer<Int32>)
+
+// CHECK-NEXT:/// line doc comment
+// CHECK-NEXT:/// 
+// CHECK-NEXT:/// Here's a more complete description.
+// CHECK-NEXT:///
+// CHECK-NEXT:/// @param len the buffer length
+// CHECK-NEXT:/// @param p the buffer
+// CHECK-NEXT:/// This is an auto-generated wrapper for safer interop
+// CHECK-NEXT:@_alwaysEmitIntoClient public func lineDocComment(_ p: UnsafeMutableBufferPointer<Int32>)

test/Interop/C/swiftify-import/counted-by-noescape.swift

@@ -11,33 +11,52 @@
 
 import CountedByNoEscapeClang
 
-// CHECK:      @available(visionOS 1.1, tvOS 12.2, watchOS 5.2, iOS 12.2, macOS 10.14.4, *)
+// CHECK:      /// This is an auto-generated wrapper for safer interop
+// CHECK-NEXT: @available(visionOS 1.1, tvOS 12.2, watchOS 5.2, iOS 12.2, macOS 10.14.4, *)
 // CHECK-NEXT: @lifetime(_param1: copy _param1)
 // CHECK-NEXT: @_alwaysEmitIntoClient public func anonymous(_ _param1: inout MutableSpan<Int32>?)
-// CHECK-NEXT:  @available(visionOS 1.1, tvOS 12.2, watchOS 5.2, iOS 12.2, macOS 10.14.4, *)
+
+// CHECK-NEXT: /// This is an auto-generated wrapper for safer interop
+// CHECK-NEXT: @available(visionOS 1.1, tvOS 12.2, watchOS 5.2, iOS 12.2, macOS 10.14.4, *)
 // CHECK-NEXT: @lifetime(p: copy p)
 // CHECK-NEXT: @_alwaysEmitIntoClient public func complexExpr(_ len: Int32, _ offset: Int32, _ p: inout MutableSpan<Int32>)
+
+// CHECK-NEXT: /// This is an auto-generated wrapper for safer interop
 // CHECK-NEXT: @available(visionOS 1.1, tvOS 12.2, watchOS 5.2, iOS 12.2, macOS 10.14.4, *)
 // CHECK-NEXT: @lifetime(p: copy p)
 // CHECK-NEXT: @_alwaysEmitIntoClient public func nonnull(_ p: inout MutableSpan<Int32>)
+
+// CHECK-NEXT: /// This is an auto-generated wrapper for safer interop
 // CHECK-NEXT: @available(visionOS 1.1, tvOS 12.2, watchOS 5.2, iOS 12.2, macOS 10.14.4, *)
 // CHECK-NEXT: @lifetime(p: copy p)
 // CHECK-NEXT: @_alwaysEmitIntoClient public func nullUnspecified(_ p: inout MutableSpan<Int32>)
+
+// CHECK-NEXT: /// This is an auto-generated wrapper for safer interop
 // CHECK-NEXT: @available(visionOS 1.1, tvOS 12.2, watchOS 5.2, iOS 12.2, macOS 10.14.4, *)
 // CHECK-NEXT: @lifetime(p: copy p)
 // CHECK-NEXT: @_alwaysEmitIntoClient public func nullable(_ p: inout MutableSpan<Int32>?)
+
+// CHECK-NEXT: /// This is an auto-generated wrapper for safer interop
 // CHECK-NEXT: @available(visionOS 1.1, tvOS 12.2, watchOS 5.2, iOS 12.2, macOS 10.14.4, *)
 // CHECK-NEXT: @lifetime(copy p)
 // CHECK-NEXT: @lifetime(p: copy p)
 // CHECK-NEXT: @_alwaysEmitIntoClient public func returnLifetimeBound(_ len1: Int32, _ p: inout MutableSpan<Int32>) -> MutableSpan<Int32>
+
+// CHECK-NEXT: /// This is an auto-generated wrapper for safer interop
 // CHECK-NEXT: @_alwaysEmitIntoClient @_disfavoredOverload public func returnPointer(_ len: Int32) -> UnsafeMutableBufferPointer<Int32>
+
+// CHECK-NEXT: /// This is an auto-generated wrapper for safer interop
 // CHECK-NEXT: @available(visionOS 1.1, tvOS 12.2, watchOS 5.2, iOS 12.2, macOS 10.14.4, *)
 // CHECK-NEXT: @lifetime(p1: copy p1)
 // CHECK-NEXT: @lifetime(p2: copy p2)
 // CHECK-NEXT: @_alwaysEmitIntoClient public func shared(_ len: Int32, _ p1: inout MutableSpan<Int32>, _ p2: inout MutableSpan<Int32>)
+
+// CHECK-NEXT: /// This is an auto-generated wrapper for safer interop
 // CHECK-NEXT: @available(visionOS 1.1, tvOS 12.2, watchOS 5.2, iOS 12.2, macOS 10.14.4, *)
 // CHECK-NEXT: @lifetime(p: copy p)
 // CHECK-NEXT: @_alwaysEmitIntoClient public func simple(_ p: inout MutableSpan<Int32>)
+
+// CHECK-NEXT: /// This is an auto-generated wrapper for safer interop
 // CHECK-NEXT: @available(visionOS 1.1, tvOS 12.2, watchOS 5.2, iOS 12.2, macOS 10.14.4, *)
 // CHECK-NEXT: @lifetime(p: copy p)
 // CHECK-NEXT: @_alwaysEmitIntoClient public func swiftAttr(_ p: inout MutableSpan<Int32>)

test/Interop/C/swiftify-import/counted-by.swift

@@ -10,23 +10,59 @@
 
 import CountedByClang
 
-// CHECK:      @_alwaysEmitIntoClient public func bitshift(_ m: Int32, _ n: Int32, _ o: Int32, _ p: UnsafeMutableBufferPointer<Int32>)
+
+// CHECK:      /// This is an auto-generated wrapper for safer interop
+// CHECK-NEXT: @_alwaysEmitIntoClient public func bitshift(_ m: Int32, _ n: Int32, _ o: Int32, _ p: UnsafeMutableBufferPointer<Int32>)
+
+// CHECK-NEXT: /// This is an auto-generated wrapper for safer interop
 // CHECK-NEXT: @_alwaysEmitIntoClient public func bitwise(_ m: Int32, _ n: Int32, _ o: Int32, _ p: UnsafeMutableBufferPointer<Int32>)
+
+// CHECK-NEXT: /// This is an auto-generated wrapper for safer interop
 // CHECK-NEXT: @_alwaysEmitIntoClient public func complexExpr(_ len: Int{{.*}}, _ offset: Int{{.*}}, _ p: UnsafeMutableBufferPointer<Int{{.*}}>)
+
+// CHECK-NEXT: /// This is an auto-generated wrapper for safer interop
 // CHECK-NEXT: @_alwaysEmitIntoClient public func constFloatCastedToInt(_ p: UnsafeMutableBufferPointer<Int32>)
+
+// CHECK-NEXT: /// This is an auto-generated wrapper for safer interop
 // CHECK-NEXT: @_alwaysEmitIntoClient public func constInt(_ p: UnsafeMutableBufferPointer<Int32>)
+
+// CHECK-NEXT: /// This is an auto-generated wrapper for safer interop
 // CHECK-NEXT: @_alwaysEmitIntoClient public func nonnull(_  p: UnsafeMutableBufferPointer<Int{{.*}}>)
+
+// CHECK-NEXT: /// This is an auto-generated wrapper for safer interop
 // CHECK-NEXT: @_alwaysEmitIntoClient public func nullUnspecified(_  p: UnsafeMutableBufferPointer<Int{{.*}}>)
+
+// CHECK-NEXT: /// This is an auto-generated wrapper for safer interop
 // CHECK-NEXT: @_alwaysEmitIntoClient public func nullable(_  p: UnsafeMutableBufferPointer<Int{{.*}}>?)
+
+// CHECK-NEXT: /// This is an auto-generated wrapper for safer interop
 // CHECK-NEXT: @_alwaysEmitIntoClient public func offByOne(_ len: Int32, _ p: UnsafeMutableBufferPointer<Int32>)
+
+// CHECK-NEXT: /// This is an auto-generated wrapper for safer interop
 // CHECK-NEXT: @_alwaysEmitIntoClient public func offBySome(_ len: Int32, _ offset: Int32, _ p: UnsafeMutableBufferPointer<Int32>)
+
+// CHECK-NEXT: /// This is an auto-generated wrapper for safer interop
 // CHECK-NEXT: @_alwaysEmitIntoClient @_disfavoredOverload public func returnPointer(_  len: Int{{.*}}) -> UnsafeMutableBufferPointer<Int{{.*}}>
+
+// CHECK-NEXT: /// This is an auto-generated wrapper for safer interop
 // CHECK-NEXT: @_alwaysEmitIntoClient public func scalar(_ m: Int32, _ n: Int32, _ p: UnsafeMutableBufferPointer<Int32>)
+
+// CHECK-NEXT: /// This is an auto-generated wrapper for safer interop
 // CHECK-NEXT: @_alwaysEmitIntoClient public func shared(_ len: Int{{.*}}, _ p1: UnsafeMutableBufferPointer<Int{{.*}}>, _ p2: UnsafeMutableBufferPointer<Int{{.*}}>)
+
+// CHECK-NEXT: /// This is an auto-generated wrapper for safer interop
 // CHECK-NEXT: @_alwaysEmitIntoClient public func simple(_  p: UnsafeMutableBufferPointer<Int{{.*}}>)
+
+// CHECK-NEXT: /// This is an auto-generated wrapper for safer interop
 // CHECK-NEXT: @_alwaysEmitIntoClient public func simpleFlipped(_  p: UnsafeMutableBufferPointer<Int{{.*}}>)
+
+// CHECK-NEXT: /// This is an auto-generated wrapper for safer interop
 // CHECK-NEXT: @_alwaysEmitIntoClient public func sizeofParam(_  p: UnsafeMutableBufferPointer<Int{{.*}}>)
+
+// CHECK-NEXT: /// This is an auto-generated wrapper for safer interop
 // CHECK-NEXT: @_alwaysEmitIntoClient public func sizeofType(_  p: UnsafeMutableBufferPointer<Int{{.*}}>)
+
+// CHECK-NEXT: /// This is an auto-generated wrapper for safer interop
 // CHECK-NEXT: @_alwaysEmitIntoClient public func swiftAttr(_  p: UnsafeMutableBufferPointer<Int{{.*}}>)
 
 @inlinable

test/Interop/C/swiftify-import/sized-by-noescape.swift

@@ -9,21 +9,39 @@
 // Check that ClangImporter correctly infers and expands @_SwiftifyImport macros for functions with __sized_by __noescape parameters.
 import SizedByNoEscapeClang
 
-// CHECK:      @available(visionOS 1.1, tvOS 12.2, watchOS 5.2, iOS 12.2, macOS 10.14.4, *)
+
+// CHECK:      /// This is an auto-generated wrapper for safer interop
+// CHECK-NEXT: @available(visionOS 1.1, tvOS 12.2, watchOS 5.2, iOS 12.2, macOS 10.14.4, *)
 // CHECK-NEXT: @_alwaysEmitIntoClient public func complexExpr(_ len: Int{{.*}}, _ offset: Int{{.*}}, _ p: RawSpan)
+
+// CHECK-NEXT: /// This is an auto-generated wrapper for safer interop
 // CHECK-NEXT: @available(visionOS 1.1, tvOS 12.2, watchOS 5.2, iOS 12.2, macOS 10.14.4, *)
 // CHECK-NEXT: @_alwaysEmitIntoClient public func nonnull(_ p: RawSpan)
+
+// CHECK-NEXT: /// This is an auto-generated wrapper for safer interop
 // CHECK-NEXT: @available(visionOS 1.1, tvOS 12.2, watchOS 5.2, iOS 12.2, macOS 10.14.4, *)
 // CHECK-NEXT: @_alwaysEmitIntoClient public func nullUnspecified(_  p: RawSpan)
+
+// CHECK-NEXT: /// This is an auto-generated wrapper for safer interop
 // CHECK-NEXT: @available(visionOS 1.1, tvOS 12.2, watchOS 5.2, iOS 12.2, macOS 10.14.4, *)
 // CHECK-NEXT: @_alwaysEmitIntoClient public func nullable(_  p: RawSpan?)
+
+// CHECK-NEXT: /// This is an auto-generated wrapper for safer interop
 // CHECK-NEXT: @available(visionOS 1.1, tvOS 12.2, watchOS 5.2, iOS 12.2, macOS 10.14.4, *)
 // CHECK-NEXT: @_alwaysEmitIntoClient public func opaque(_  p: RawSpan)
+
+// CHECK-NEXT: /// This is an auto-generated wrapper for safer interop
 // CHECK-NEXT: @_alwaysEmitIntoClient @_disfavoredOverload public func returnPointer(_ len: Int{{.*}}) -> UnsafeRawBufferPointer
+
+// CHECK-NEXT: /// This is an auto-generated wrapper for safer interop
 // CHECK-NEXT: @available(visionOS 1.1, tvOS 12.2, watchOS 5.2, iOS 12.2, macOS 10.14.4, *)
 // CHECK-NEXT: @_alwaysEmitIntoClient public func shared(_ len: Int{{.*}}, _ p1: RawSpan, _ p2: RawSpan)
+
+// CHECK-NEXT: /// This is an auto-generated wrapper for safer interop
 // CHECK-NEXT: @available(visionOS 1.1, tvOS 12.2, watchOS 5.2, iOS 12.2, macOS 10.14.4, *)
 // CHECK-NEXT: @_alwaysEmitIntoClient public func simple(_  p: RawSpan)
+
+// CHECK-NEXT: /// This is an auto-generated wrapper for safer interop
 // CHECK-NEXT: @available(visionOS 1.1, tvOS 12.2, watchOS 5.2, iOS 12.2, macOS 10.14.4, *)
 // CHECK-NEXT: @_alwaysEmitIntoClient public func swiftAttr(_  p: RawSpan)
 

test/Interop/C/swiftify-import/sized-by.swift

@@ -9,14 +9,32 @@
 // Check that ClangImporter correctly infers and expands @_SwiftifyImport macros for functions with __sized_by parameters.
 import SizedByClang
 
-// CHECK:      @_alwaysEmitIntoClient public func complexExpr(_ len: Int{{.*}}, _ offset: Int{{.*}}, _ p: UnsafeMutableRawBufferPointer)
+
+// CHECK:      /// This is an auto-generated wrapper for safer interop
+// CHECK-NEXT: @_alwaysEmitIntoClient public func complexExpr(_ len: Int{{.*}}, _ offset: Int{{.*}}, _ p: UnsafeMutableRawBufferPointer)
+
+// CHECK-NEXT: /// This is an auto-generated wrapper for safer interop
 // CHECK-NEXT: @_alwaysEmitIntoClient public func nonnull(_  p: UnsafeMutableRawBufferPointer)
+
+// CHECK-NEXT: /// This is an auto-generated wrapper for safer interop
 // CHECK-NEXT: @_alwaysEmitIntoClient public func nullUnspecified(_  p: UnsafeMutableRawBufferPointer)
+
+// CHECK-NEXT: /// This is an auto-generated wrapper for safer interop
 // CHECK-NEXT: @_alwaysEmitIntoClient public func nullable(_  p: UnsafeMutableRawBufferPointer?)
+
+// CHECK-NEXT: /// This is an auto-generated wrapper for safer interop
 // CHECK-NEXT: @_alwaysEmitIntoClient public func opaque(_  p: UnsafeRawBufferPointer)
+
+// CHECK-NEXT: /// This is an auto-generated wrapper for safer interop
 // CHECK-NEXT: @_alwaysEmitIntoClient @_disfavoredOverload public func returnPointer(_ len: Int{{.*}}) -> UnsafeMutableRawBufferPointer
+
+// CHECK-NEXT: /// This is an auto-generated wrapper for safer interop
 // CHECK-NEXT: @_alwaysEmitIntoClient public func shared(_ len: Int{{.*}}, _ p1: UnsafeMutableRawBufferPointer, _ p2: UnsafeMutableRawBufferPointer)
+
+// CHECK-NEXT: /// This is an auto-generated wrapper for safer interop
 // CHECK-NEXT: @_alwaysEmitIntoClient public func simple(_  p: UnsafeMutableRawBufferPointer)
+
+// CHECK-NEXT: /// This is an auto-generated wrapper for safer interop
 // CHECK-NEXT: @_alwaysEmitIntoClient public func swiftAttr(_  p: UnsafeMutableRawBufferPointer)
 
 @inlinable