Merge pull request swiftlang#63586 from bnbarham/load-should-respect-overlay

[Macros] Respect VFS overlays when loading plugins

Author: DougGregor

lib/AST/ASTContext.cpp

@@ -6204,10 +6204,19 @@ BuiltinTupleType *ASTContext::getBuiltinTupleType() {
 
 void ASTContext::loadCompilerPlugins() {
   for (auto &path : SearchPathOpts.getCompilerPluginLibraryPaths()) {
+    auto fs = this->SourceMgr.getFileSystem();
+    SmallString<128> resolvedPath;
+    if (auto err = fs->getRealPath(path, resolvedPath)) {
+      Diags.diagnose(SourceLoc(), diag::compiler_plugin_not_loaded, path,
+                     err.message());
+      continue;
+    }
+
     void *lib = nullptr;
 #if !defined(_WIN32)
-    lib = dlopen(path.c_str(), RTLD_LAZY|RTLD_LOCAL);
+    lib = dlopen(resolvedPath.c_str(), RTLD_LAZY|RTLD_LOCAL);
 #endif
+
     if (!lib) {
       const char *errorMsg = "Unsupported platform";
 #if !defined(_WIN32)
@@ -6218,7 +6227,7 @@ void ASTContext::loadCompilerPlugins() {
       continue;
     }
 
-    getImpl().LoadedPluginPaths.push_back({path, lib});
+    getImpl().LoadedPluginPaths.emplace_back(resolvedPath.str().str(), lib);
   }
 }
 

lib/Sema/TypeCheckMacros.cpp

@@ -301,9 +301,12 @@ MacroDefinition MacroDefinitionRequest::evaluate(
 }
 
 /// Load a plugin library based on a module name.
-static void *loadPluginByName(StringRef searchPath, StringRef moduleName) {
+static void *loadPluginByName(StringRef searchPath, StringRef moduleName, llvm::vfs::FileSystem &fs) {
   SmallString<128> fullPath(searchPath);
   llvm::sys::path::append(fullPath, "lib" + moduleName + LTDL_SHLIB_EXT);
+  if (fs.getRealPath(fullPath, fullPath))
+    return nullptr;
+
 #if defined(_WIN32)
   return LoadLibraryA(fullPath.c_str());
 #else
@@ -314,9 +317,10 @@ static void *loadPluginByName(StringRef searchPath, StringRef moduleName) {
 void *CompilerPluginLoadRequest::evaluate(
     Evaluator &evaluator, ASTContext *ctx, Identifier moduleName
 ) const {
+  auto fs = ctx->SourceMgr.getFileSystem();
   auto &searchPathOpts = ctx->SearchPathOpts;
   for (const auto &path : searchPathOpts.PluginSearchPaths) {
-    if (auto found = loadPluginByName(path, moduleName.str()))
+    if (auto found = loadPluginByName(path, moduleName.str(), *fs))
       return found;
   }
 

test/Macros/macro_vfs.swift

@@ -0,0 +1,31 @@
+// RUN: %empty-directory(%t)
+// RUN: %empty-directory(%t/hidden)
+// RUN: split-file %s %t
+// RUN: sed -e "s@VFS_DIR@%{/t:regex_replacement}/vfs@g" -e "s@EXTERNAL_DIR@%{/t:regex_replacement}/hidden@g" %t/base.yaml > %t/overlay.yaml
+
+// RUN: %target-build-swift -swift-version 5 -I %swift-host-lib-dir -L %swift-host-lib-dir -emit-library -o %t/hidden/%target-library-name(MacroDefinition) -module-name=MacroDefinition %S/Inputs/syntax_macro_definitions.swift -g -no-toolchain-stdlib-rpath -swift-version 5
+
+// Check that loading plugins respects VFS overlays
+// RUN: %target-swift-frontend -typecheck -verify -swift-version 5 -enable-experimental-feature Macros -load-plugin-library %t/vfs/%target-library-name(MacroDefinition) -I %swift-host-lib-dir -module-name MacroUser -DTEST_DIAGNOSTICS %t/macro.swift -vfsoverlay %t/overlay.yaml
+// RUN: %target-swift-frontend -typecheck -verify -swift-version 5 -enable-experimental-feature Macros -plugin-path %t/vfs -I %swift-host-lib-dir -module-name MacroUser -DTEST_DIAGNOSTICS %t/macro.swift -vfsoverlay %t/overlay.yaml
+
+// FIXME: Swift parser is not enabled on Linux CI yet.
+// REQUIRES: OS=macosx
+
+//--- macro.swift
+// expected-no-diagnostics
+@freestanding(expression) macro customFileID() -> String = #externalMacro(module: "MacroDefinition", type: "FileIDMacro")
+let _ = #customFileID
+
+//--- base.yaml
+{
+  version: 0,
+  roots: [
+    {
+      type: "directory-remap",
+      name: "VFS_DIR",
+      external-contents: "EXTERNAL_DIR"
+    }
+  ]
+}
+