[native_toolchain_c] Fix clang compiler search + tools when using swiftly

pkgs/native_toolchain_c/lib/src/native_toolchain/apple_clang.dart

@@ -2,6 +2,8 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
+import 'package:code_assets/code_assets.dart';
+
 import '../tool/tool.dart';
 import '../tool/tool_resolver.dart';
 
@@ -31,6 +33,10 @@ final Tool appleAr = Tool(
       wrappedResolver: appleClang.defaultResolver!,
       relativePath: Uri.file('ar'),
     ),
+    PathToolResolver(
+      toolName: 'Apple archiver',
+      executableName: OS.current.executableFileName('ar'),
+    ),
   ]),
 );
 
@@ -43,6 +49,15 @@ final Tool appleLd = Tool(
       wrappedResolver: appleClang.defaultResolver!,
       relativePath: Uri.file('ld'),
     ),
+    PathToolResolver(
+      toolName: 'Apple linker',
+      executableName: OS.current.executableFileName('ld'),
+    ),
+    RelativeToolResolver(
+      toolName: 'Apple linker',
+      wrappedResolver: appleClang.defaultResolver!,
+      relativePath: Uri.file(OS.current.executableFileName('ld.lld')),
+    ),
   ]),
 );
 

pkgs/native_toolchain_c/lib/src/tool/tool_resolver.dart

@@ -2,6 +2,7 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
+import 'dart:async';
 import 'dart:convert';
 import 'dart:io';
 
@@ -65,8 +66,10 @@ class PathToolResolver extends ToolResolver {
     if (process.exitCode == 0) {
       final file = File(LineSplitter.split(process.stdout).first);
       final uri = File(await file.resolveSymbolicLinks()).uri;
-      if (uri.pathSegments.last == 'llvm') {
+      if (uri.pathSegments.last == 'llvm' ||
+          uri.pathSegments.last == 'swiftly') {
         // https://github.com/dart-lang/native/issues/136
+        // https://github.com/dart-lang/native/issues/2792
         return file.uri;
       }
       return uri;