Commit my clang plugin and fix up documentation.

tools/clang/plugins/ChromeClassTester.cpp

Index: tools/clang/plugins/ChromeClassTester.cpp
diff --git a/tools/clang/plugins/ChromeClassTester.cpp b/tools/clang/plugins/ChromeClassTester.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..106f16ec0bbaf6b3e2d4698cb824a185d922a349
--- /dev/null
+++ b/tools/clang/plugins/ChromeClassTester.cpp
@@ -0,0 +1,208 @@
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// A general interface for filtering and only acting on classes in Chromium C++
+// code.
+
+#include "ChromeClassTester.h"
+
+#include "clang/Basic/FileManager.h"
+
+using namespace clang;
+
+namespace {
+
+bool starts_with(const std::string& one, const std::string& two) {
+  return one.substr(0, two.size()) == two;
+}
+
+bool ends_with(const std::string& one, const std::string& two) {
+  return one.substr(one.size() - two.size(), two.size()) == two;
+}
+
+}  // namespace
+
+ChromeClassTester::ChromeClassTester(CompilerInstance& instance)
+    : instance_(instance),
+      diagnostic_(instance.getDiagnostics()) {
+  banned_namespaces_.push_back("std");
+  banned_namespaces_.push_back("__gnu_cxx");
+
+  banned_directories_.push_back("third_party");
+  banned_directories_.push_back("native_client");
+  banned_directories_.push_back("breakpad");
+  banned_directories_.push_back("courgette");
+  banned_directories_.push_back("ppapi");
+  banned_directories_.push_back("/usr");
+  banned_directories_.push_back("testing");
+  banned_directories_.push_back("googleurl");
+  banned_directories_.push_back("v8");
+  banned_directories_.push_back("sdch");
+
+  // You are standing in a mazy of twisty dependencies, all resolved by
+  // putting everything in the header.
+  banned_directories_.push_back("chrome/test/automation");
+
+  // Used in really low level threading code that probably shouldn't be out of
+  // lined.
+  ignored_record_names_.push_back("ThreadLocalBoolean");
+
+  // A complicated pickle derived struct that is all packed integers.
+  ignored_record_names_.push_back("Header");
+
+  // Part of the GPU system that uses multiple included header
+  // weirdness. Never getting this right.
+  ignored_record_names_.push_back("Validators");
+
+  // RAII class that's simple enough (media/base/callback.h).
+  ignored_record_names_.push_back("AutoTaskRunner");
+  ignored_record_names_.push_back("AutoCallbackRunner");
+
+  // Part of our public interface that nacl and friends use. (Arguably, this
+  // should mean that this is a higher priority but fixing this looks hard.)
+  ignored_record_names_.push_back("PluginVersionInfo");
+}
+
+ChromeClassTester::~ChromeClassTester() {}
+
+void ChromeClassTester::HandleTagDeclDefinition(TagDecl* tag) {
+  if (CXXRecordDecl* record = dyn_cast<CXXRecordDecl>(tag)) {
+    // If this is a POD or a class template or a type dependent on a
+    // templated class, assume there's no ctor/dtor/virtual method
+    // optimization that we can do.
+    if (record->isPOD() ||
+        record->getDescribedClassTemplate() ||
+        record->getTemplateSpecializationKind() ||
+        record->isDependentType())
+      return;
+
+    if (InBannedNamespace(record))
+      return;
+
+    SourceLocation record_location = record->getInnerLocStart();
+    if (InBannedDirectory(record_location))
+      return;
+
+    // For now, due to large amounts of inlining in our unit test code, there's
+    // no way in hell we'll pass our checks but we want to deploy clang plugins
+    // now.
+    //
+    // TODO(erg): Deinline all our test code, and only perform something like
+    // this check for the "virtual" inlining tests on GMOCK code (since all of
+    // that is autogenerated and doesn't specify the "virtual" keyword).
+    if (IsTestCode(record)) {
+      return;
+    }
+
+    // We sadly need to maintain a blacklist of types that violate these
+    // rules, but do so for good reason or due to limitations of this
+    // checker (i.e., we don't handle extern templates very well).
+    if (IsIgnoredType(record))
+      return;
+
+    CheckChromeClass(record_location, record);
+  }
+}
+
+void ChromeClassTester::emitWarning(SourceLocation loc, const char* raw_error) {
+  FullSourceLoc full(loc, instance().getSourceManager());
+  std::string err;
+  err = "[chrome-style] ";
+  err += raw_error;
+  unsigned id = diagnostic().getCustomDiagID(Diagnostic::Warning, err);
+  DiagnosticBuilder B = diagnostic().Report(full, id);
+}
+
+bool ChromeClassTester::IsTestCode(Decl* record) {
+  if (instance_.hasSourceManager()) {
+    SourceManager& m = instance_.getSourceManager();
+    std::string name = m.getFileEntryForID(m.getMainFileID())->getName();
+    return name.find("test") != name.npos ||
+        name.find("mock") != name.npos;
+  }
+  return false;
+}
+
+bool ChromeClassTester::InBannedNamespace(Decl* record) {
+  std::string n = GetNamespace(record);
+  if (n != "") {
+    return std::find(banned_namespaces_.begin(), banned_namespaces_.end(), n)
+        != banned_namespaces_.end();
+  }
+
+  return false;
+}
+
+std::string ChromeClassTester::GetNamespace(Decl* record) {
+  return GetNamespaceImpl(record->getDeclContext(), "");
+}
+
+std::string ChromeClassTester::GetNamespaceImpl(const DeclContext* context,
+                                                std::string candidate) {
+  switch (context->getDeclKind()) {
+    case Decl::TranslationUnit: {
+      return candidate;
+    }
+    case Decl::Namespace: {
+      const NamespaceDecl* decl = dyn_cast<NamespaceDecl>(context);
+      std::string name_str;
+      llvm::raw_string_ostream OS(name_str);
+      if (decl->isAnonymousNamespace())
+        OS << "<anonymous namespace>";
+      else
+        OS << decl;
+      return GetNamespaceImpl(context->getParent(),
+                              OS.str());
+    }
+    default: {
+      return GetNamespaceImpl(context->getParent(), candidate);
+    }
+  }
+}
+
+bool ChromeClassTester::InBannedDirectory(const SourceLocation& loc) {
+  if (loc.isFileID() && loc.isValid()) {
+    bool invalid = false;
+    const char* buffer_name = instance_.getSourceManager().getBufferName(
+        loc, &invalid);
+    if (!invalid && buffer_name) {
+      std::string b(buffer_name);
+
+      // Don't complain about these things in implementation files.
+      if (ends_with(b, ".cc") || ends_with(b, ".cpp")) {
+        return true;
+      }
+
+      // Don't complain about autogenerated protobuf files.
+      if (ends_with(b, ".pb.h")) {
+        return true;
+      }
+
+      // Strip preceding path crap.
+      if (starts_with(b, "./"))
+        b = b.substr(2);
+
+      for (std::vector<std::string>::const_iterator it =
+               banned_directories_.begin();
+           it != banned_directories_.end(); ++it) {
+        if (starts_with(b, *it))
+          return true;
+      }
+    }
+  }
+
+  return false;
+}
+
+bool ChromeClassTester::IsIgnoredType(RecordDecl* record) {
+  std::string base_name = record->getNameAsString();
+  for (std::vector<std::string>::const_iterator it =
+           ignored_record_names_.begin();
+       it != ignored_record_names_.end(); ++it) {
+    if (base_name == *it)
+      return true;
+  }
+
+  return false;
+}