[Darwin macro platform paths] Add iOS simulator test

Author: DougGregor

test/Driver/compiler_plugin_path_iphonesimulator.swift

@@ -0,0 +1,24 @@
+// RUN: %target-swiftc_driver -driver-print-jobs -target x86_64-apple-ios15.0-simulator %s 2>&1 | %FileCheck %s
+// REQUIRES: OS=ios
+
+// CHECK: -external-plugin-path
+// CHECK-SAME: .sdk/usr/lib/swift/host/plugins#
+// CHECK-SAME: .sdk/usr/bin/swift-plugin-server
+
+// CHECK-SAME: -external-plugin-path
+// CHECK-SAME: .sdk/usr/local/lib/swift/host/plugins#
+// CHECK-SAME: .sdk/usr/bin/swift-plugin-server
+
+// CHECK-SAME: -external-plugin-path
+// CHECK-SAME: iPhoneOS.platform/Developer/usr/lib/swift/host/plugins#
+// CHECK-SAME: iPhoneOS.platform/Developer/usr/bin/swift-plugin-server
+
+// CHECK-SAME: -external-plugin-path
+// CHECK-SAME: iPhoneOS.platform/Developer/usr/local/lib/swift/host/plugins#
+// CHECK-SAME: iPhoneOS.platform/Developer/usr/bin/swift-plugin-server
+
+// CHECK-SAME: -plugin-path
+// CHECK-SAME: {{(/|\\\\)}}lib{{(/|\\\\)}}swift{{(/|\\\\)}}host{{(/|\\\\)}}plugins
+
+// CHECK-SAME: -plugin-path
+// CHECK-SAME: {{(/|\\\\)}}local{{(/|\\\\)}}lib{{(/|\\\\)}}swift{{(/|\\\\)}}host{{(/|\\\\)}}plugins