GN: Check if targets with precompiled headers use unsupported toolchains.

tools/gn/target_unittest.cc

 // Copyright (c) 2013 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.
 
 #include "tools/gn/target.h"
 
 #include <utility>
 
 #include "testing/gtest/include/gtest/gtest.h"
 #include "tools/gn/build_settings.h"
@@ skipping 851 matching lines @@
       "From //foo:bar\n"
       "  header: pch.h\n"
       "  source: //pcs.cc\n"
       "\n"
       "From //foo:c2\n"
       "  header: pch2.h\n"
       "  source: //pcs2.cc",
       err.help_text());
 }
 
+TEST(Target, PrecompiledHeaderSupport) {
+  TestWithScope setup;
+  Err err;
+
+  std::string pch_1("pch.h");
+  SourceFile pcs_1("//pcs.cc");
+
+  // No source files, so it doesn't matter
+  TestTarget a(setup, "//a", Target::SOURCE_SET);
+  a.config_values().set_precompiled_header(pch_1);
+  a.config_values().set_precompiled_source(pcs_1);
+  ASSERT_TRUE(a.OnResolved(&err));
+
+  // TestWithScope toolchain doesn't support precompiled headers.
+  TestTarget b(setup, "//b", Target::SOURCE_SET);
+  b.config_values().set_precompiled_header(pch_1);
+  b.config_values().set_precompiled_source(pcs_1);
+  b.sources().push_back(SourceFile("//foo/b1.c"));
+  ASSERT_FALSE(b.OnResolved(&err));
+
+  Tool* cxx = setup.toolchain()->GetTool(Toolchain::TYPE_CXX);
+  ASSERT_NE(nullptr, cxx);
+
+  cxx->set_precompiled_header_type(Tool::PCH_GCC);
+
+  // CXX tool now supports PCHs.
+  TestTarget c(setup, "//c", Target::SOURCE_SET);
+  c.config_values().set_precompiled_header(pch_1);
+  c.config_values().set_precompiled_source(pcs_1);
+  c.sources().push_back(SourceFile("//foo/c1.cpp"));
+  ASSERT_TRUE(c.OnResolved(&err));
+}
+
 TEST(Target, AssertNoDeps) {
   TestWithScope setup;
   Err err;
 
   // A target.
   TestTarget a(setup, "//a", Target::SHARED_LIBRARY);
   ASSERT_TRUE(a.OnResolved(&err));
 
   // B depends on A and has an assert_no_deps for a random dir.
   TestTarget b(setup, "//b", Target::SHARED_LIBRARY);
@@ skipping 105 matching lines @@
   ASSERT_EQ(c.bundle_data().file_rules().size(), 1u);
   ASSERT_EQ(c.bundle_data().file_rules()[0].sources().size(), 1u);
   ASSERT_EQ(c.bundle_data().bundle_deps().size(), 1u);
 
   // E does not have any bundle_data information but gets a list of
   // bundle_deps to propagate them during target resolution.
   ASSERT_TRUE(e.bundle_data().file_rules().empty());
   ASSERT_TRUE(e.bundle_data().assets_catalog_sources().empty());
   ASSERT_EQ(e.bundle_data().bundle_deps().size(), 2u);
 }