Migrate compatible uses to TestRawOstream. (#2891)

Replacing direct raw_string_ostream uses. I figure the wrapper should be used more consistently.

There are still remaining raw_string_ostream uses that weren't compatible -- I'm continuing to look at those, but felt it was cleaner to have this on its own.

common/BUILD

@@ -55,6 +55,7 @@ cc_test(
         ":enum_base",
         ":enum_base_test_def",
         "//testing/util:gtest_main",
+        "//testing/util:test_raw_ostream",
         "@com_google_googletest//:gtest",
     ],
 )
@@ -75,6 +76,7 @@ cc_test(
     deps = [
         ":error",
         "//testing/util:gtest_main",
+        "//testing/util:test_raw_ostream",
         "@com_google_googletest//:gtest",
     ],
 )
@@ -156,6 +158,7 @@ cc_test(
     deps = [
         ":vlog",
         "//testing/util:gtest_main",
+        "//testing/util:test_raw_ostream",
         "@com_google_googletest//:gtest",
     ],
 )

common/enum_base_test.cpp

@@ -6,8 +6,11 @@
 
 #include <gtest/gtest.h>
 
+#include "testing/util/test_raw_ostream.h"
+
 namespace Carbon {
 
+// These are directly in the Carbon namespace because the defines require it.
 CARBON_DEFINE_RAW_ENUM_CLASS(TestKind, uint8_t) {
 #define CARBON_ENUM_BASE_TEST_KIND(Name) CARBON_RAW_ENUM_ENUMERATOR(Name)
 #include "common/enum_base_test.def"
@@ -31,6 +34,7 @@ CARBON_DEFINE_ENUM_CLASS_NAMES(TestKind) = {
 #include "common/enum_base_test.def"
 };
 
+namespace Testing {
 namespace {
 
 TEST(EnumBaseTest, NamesAndConstants) {
@@ -40,8 +44,7 @@ TEST(EnumBaseTest, NamesAndConstants) {
 }
 
 TEST(EnumBaseTest, Printing) {
-  std::string s;
-  llvm::raw_string_ostream stream(s);
+  TestRawOstream stream;
 
   TestKind kind = TestKind::Beep;
   stream << kind << " " << TestKind::Beep;
@@ -50,7 +53,7 @@ TEST(EnumBaseTest, Printing) {
 
   // Check the streamed results and also make sure we can stream into GoogleTest
   // assertions.
-  EXPECT_EQ("Beep Beep Boop", s) << "Final kind: " << kind;
+  EXPECT_EQ("Beep Beep Boop", stream.TakeStr()) << "Final kind: " << kind;
 }
 
 TEST(EnumBaseTest, Switch) {
@@ -105,4 +108,5 @@ TEST(EnumBaseTest, IntConversion) {
 }
 
 }  // namespace
+}  // namespace Testing
 }  // namespace Carbon

common/error_test.cpp

@@ -6,6 +6,8 @@
 
 #include <gtest/gtest.h>
 
+#include "testing/util/test_raw_ostream.h"
+
 namespace Carbon::Testing {
 namespace {
 
@@ -98,15 +100,16 @@ TEST(ErrorTest, AssignOrReturnHasErrorInExpected) {
 }
 
 TEST(ErrorTest, ErrorBuilderOperatorImplicitCast) {
-  ErrorOr<int> result1 = ErrorBuilder() << "msg";
-  ASSERT_FALSE(result1.ok());
-  EXPECT_EQ(result1.error().message(), "msg");
+  ErrorOr<int> result = ErrorBuilder() << "msg";
+  ASSERT_FALSE(result.ok());
+  EXPECT_EQ(result.error().message(), "msg");
+}
 
-  auto result2 = static_cast<Error>(ErrorBuilder("TestFunc") << "msg");
-  std::string result2_output;
-  llvm::raw_string_ostream oss(result2_output);
-  result2.Print(oss);
-  EXPECT_EQ(oss.str(), "TestFunc: msg");
+TEST(ErrorTest, StreamError) {
+  Error result = ErrorBuilder("TestFunc") << "msg";
+  TestRawOstream result_stream;
+  result_stream << result;
+  EXPECT_EQ(result_stream.TakeStr(), "TestFunc: msg");
 }
 
 }  // namespace

common/vlog_test.cpp

@@ -7,6 +7,8 @@
 #include <gmock/gmock.h>
 #include <gtest/gtest.h>
 
+#include "testing/util/test_raw_ostream.h"
+
 namespace Carbon::Testing {
 namespace {
 
@@ -16,7 +18,7 @@ using ::testing::StrEq;
 // Helper class with a vlog_stream_ member for CARBON_VLOG.
 class VLogger {
  public:
-  explicit VLogger(bool enable) : buffer_(buffer_str_) {
+  explicit VLogger(bool enable) {
     if (enable) {
       vlog_stream_ = &buffer_;
     }
@@ -24,11 +26,10 @@ class VLogger {
 
   void VLog() { CARBON_VLOG() << "Test\n"; }
 
-  auto buffer() -> llvm::StringRef { return buffer_str_; }
+  auto TakeStr() -> std::string { return buffer_.TakeStr(); }
 
  private:
-  std::string buffer_str_;
-  llvm::raw_string_ostream buffer_;
+  TestRawOstream buffer_;
 
   llvm::raw_ostream* vlog_stream_ = nullptr;
 };
@@ -36,13 +37,13 @@ class VLogger {
 TEST(VLogTest, Enabled) {
   VLogger vlog(/*enable=*/true);
   vlog.VLog();
-  EXPECT_THAT(vlog.buffer(), StrEq("Test\n"));
+  EXPECT_THAT(vlog.TakeStr(), StrEq("Test\n"));
 }
 
 TEST(VLogTest, Disabled) {
   VLogger vlog(/*enable=*/false);
   vlog.VLog();
-  EXPECT_THAT(vlog.buffer(), IsEmpty());
+  EXPECT_THAT(vlog.TakeStr(), IsEmpty());
 }
 
 }  // namespace

explorer/BUILD

@@ -50,6 +50,7 @@ file_test(
     deps = [
         "//explorer/parse_and_execute",
         "//testing/file_test:file_test_base",
+        "//testing/util:test_raw_ostream",
     ],
 )
 

explorer/common/BUILD

@@ -28,6 +28,7 @@ cc_test(
         ":error_builders",
         ":source_location",
         "//testing/util:gtest_main",
+        "//testing/util:test_raw_ostream",
         "@com_google_googletest//:gtest",
     ],
 )

explorer/common/error_builders_test.cpp

@@ -7,22 +7,19 @@
 #include <gtest/gtest.h>
 
 #include "explorer/common/source_location.h"
+#include "testing/util/test_raw_ostream.h"
 
 namespace Carbon::Testing {
 namespace {
 
-auto ToString(const Error& err) -> std::string {
-  std::string result;
-  llvm::raw_string_ostream out(result);
-  err.Print(out);
-  return result;
-}
-
 TEST(ErrorBuildersTest, ProgramError) {
   Error err = ProgramError(SourceLocation("x", 1)) << "test";
   EXPECT_EQ(err.location(), "x:1");
   EXPECT_EQ(err.message(), "test");
-  EXPECT_EQ(ToString(err), "x:1: test");
+
+  TestRawOstream out;
+  out << err;
+  EXPECT_EQ(out.TakeStr(), "x:1: test");
 }
 
 }  // namespace

explorer/file_test.cpp

@@ -4,6 +4,7 @@
 
 #include "explorer/parse_and_execute/parse_and_execute.h"
 #include "testing/file_test/file_test_base.h"
+#include "testing/util/test_raw_ostream.h"
 
 namespace Carbon::Testing {
 namespace {
@@ -43,8 +44,7 @@ class ParseAndExecuteTestFile : public FileTestBase {
 
     // Capture trace streaming, but only when in debug mode.
     TraceStream trace_stream;
-    std::string trace_stream_str;
-    llvm::raw_string_ostream trace_stream_ostream(trace_stream_str);
+    TestRawOstream trace_stream_ostream;
     if (trace_) {
       trace_stream.set_stream(&trace_stream_ostream);
       trace_stream.set_allowed_phases({ProgramPhase::All});
@@ -69,7 +69,7 @@ class ParseAndExecuteTestFile : public FileTestBase {
     }
 
     if (trace_) {
-      EXPECT_FALSE(trace_stream_str.empty())
+      EXPECT_FALSE(trace_stream_ostream.TakeStr().empty())
           << "Tracing should always do something";
     }
 

explorer/fuzzing/BUILD

@@ -48,6 +48,7 @@ cc_test(
         "//common/fuzzing:carbon_cc_proto",
         "//common/fuzzing:proto_to_carbon_lib",
         "//explorer/syntax",
+        "//testing/util:test_raw_ostream",
         "@com_google_googletest//:gtest",
         "@com_google_protobuf//:protobuf_headers",
     ],

explorer/fuzzing/ast_to_proto_test.cpp

@@ -16,6 +16,7 @@
 
 #include "common/fuzzing/proto_to_carbon.h"
 #include "explorer/syntax/parse.h"
+#include "testing/util/test_raw_ostream.h"
 
 namespace Carbon::Testing {
 namespace {
@@ -29,14 +30,13 @@ static std::vector<llvm::StringRef>* carbon_files = nullptr;
 
 // Returns a string representation of `ast`.
 auto AstToString(const AST& ast) -> std::string {
-  std::string s;
-  llvm::raw_string_ostream out(s);
+  TestRawOstream out;
   out << "package " << ast.package.package << (ast.is_api ? "api" : "impl")
       << ";\n";
   for (auto* declaration : ast.declarations) {
     out << *declaration << "\n";
   }
-  return s;
+  return out.TakeStr();
 }
 
 // Concatenates message and field names.

testing/file_test/BUILD

@@ -13,6 +13,7 @@ cc_library(
     hdrs = ["file_test_base.h"],
     deps = [
         "//common:check",
+        "//testing/util:test_raw_ostream",
         "@com_google_googletest//:gtest",
         "@llvm-project//llvm:Support",
     ],

testing/file_test/file_test_base.cpp

@@ -10,6 +10,7 @@
 #include "common/check.h"
 #include "llvm/ADT/Twine.h"
 #include "llvm/Support/InitLLVM.h"
+#include "testing/util/test_raw_ostream.h"
 
 namespace Carbon::Testing {
 
@@ -78,11 +79,9 @@ auto FileTestBase::TestBody() -> void {
   }
 
   // Capture trace streaming, but only when in debug mode.
-  std::string stdout;
-  std::string stderr;
-  llvm::raw_string_ostream stdout_ostream(stdout);
-  llvm::raw_string_ostream stderr_ostream(stderr);
-  bool run_succeeded = RunWithFiles(test_files, stdout_ostream, stderr_ostream);
+  TestRawOstream stdout;
+  TestRawOstream stderr;
+  bool run_succeeded = RunWithFiles(test_files, stdout, stderr);
   if (HasFailure()) {
     return;
   }
@@ -92,8 +91,8 @@ auto FileTestBase::TestBody() -> void {
          "is expected to fail.";
 
   // Check results.
-  EXPECT_THAT(SplitOutput(stdout), ElementsAreArray(expected_stdout));
-  EXPECT_THAT(SplitOutput(stderr), ElementsAreArray(expected_stderr));
+  EXPECT_THAT(SplitOutput(stdout.TakeStr()), ElementsAreArray(expected_stdout));
+  EXPECT_THAT(SplitOutput(stderr.TakeStr()), ElementsAreArray(expected_stderr));
 }
 
 auto FileTestBase::ProcessTestFile(

toolchain/driver/BUILD

@@ -49,6 +49,7 @@ cc_fuzz_test(
     corpus = glob(["fuzzer_corpus/*"]),
     deps = [
         ":driver",
+        "//testing/util:test_raw_ostream",
         "@llvm-project//llvm:Support",
     ],
 )

toolchain/driver/driver_fuzzer.cpp

@@ -10,6 +10,7 @@
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/Support/raw_ostream.h"
+#include "testing/util/test_raw_ostream.h"
 #include "toolchain/driver/driver.h"
 
 namespace Carbon::Testing {
@@ -67,12 +68,10 @@ extern "C" auto LLVMFuzzerTestOneInput(const unsigned char* data, size_t size)
   }
 
   llvm::vfs::InMemoryFileSystem fs;
-  std::string error_text;
-  llvm::raw_string_ostream error_stream(error_text);
+  TestRawOstream error_stream;
   Driver d(fs, llvm::nulls(), error_stream);
   if (!d.RunFullCommand(args)) {
-    error_stream.flush();
-    if (error_text.find("ERROR:") == std::string::npos) {
+    if (error_stream.TakeStr().find("ERROR:") == std::string::npos) {
       llvm::errs() << "No error message on a failure!\n";
       return 1;
     }

toolchain/lexer/BUILD

@@ -209,6 +209,7 @@ cc_test(
         ":tokenized_buffer",
         ":tokenized_buffer_test_helpers",
         "//testing/util:gtest_main",
+        "//testing/util:test_raw_ostream",
         "//toolchain/common:yaml_test_helpers",
         "//toolchain/diagnostics:diagnostic_emitter",
         "//toolchain/diagnostics:mocks",

toolchain/lexer/tokenized_buffer_test.cpp

@@ -14,6 +14,7 @@
 #include "llvm/ADT/SmallString.h"
 #include "llvm/Support/SourceMgr.h"
 #include "llvm/Support/raw_ostream.h"
+#include "testing/util/test_raw_ostream.h"
 #include "toolchain/common/yaml_test_helpers.h"
 #include "toolchain/diagnostics/diagnostic_emitter.h"
 #include "toolchain/diagnostics/mocks.h"
@@ -1103,12 +1104,10 @@ TEST_F(LexerTest, PrintingAsYaml) {
   // Test that we can parse this into YAML and verify line and indent data.
   auto buffer = Lex("\n ;\n\n\n; ;\n\n\n\n\n\n\n\n\n\n\n");
   ASSERT_FALSE(buffer.has_errors());
-  std::string print_output;
-  llvm::raw_string_ostream print_stream(print_output);
+  TestRawOstream print_stream;
   buffer.Print(print_stream);
-  print_stream.flush();
 
-  EXPECT_THAT(Yaml::Value::FromText(print_output),
+  EXPECT_THAT(Yaml::Value::FromText(print_stream.TakeStr()),
               ElementsAre(Yaml::SequenceValue{
                   Yaml::MappingValue{{"index", "0"},
                                      {"kind", "Semi"},

toolchain/parser/BUILD

@@ -63,6 +63,7 @@ cc_test(
         ":parse_tree",
         "//common:ostream",
         "//testing/util:gtest_main",
+        "//testing/util:test_raw_ostream",
         "//toolchain/common:yaml_test_helpers",
         "//toolchain/diagnostics:diagnostic_emitter",
         "//toolchain/diagnostics:mocks",

toolchain/parser/parse_tree_test.cpp

@@ -9,6 +9,7 @@
 
 #include <forward_list>
 
+#include "testing/util/test_raw_ostream.h"
 #include "toolchain/common/yaml_test_helpers.h"
 #include "toolchain/diagnostics/diagnostic_emitter.h"
 #include "toolchain/diagnostics/mocks.h"
@@ -51,10 +52,8 @@ TEST_F(ParseTreeTest, PrintPostorderAsYAML) {
   TokenizedBuffer tokens = GetTokenizedBuffer("fn F();");
   ParseTree tree = ParseTree::Parse(tokens, consumer, /*vlog_stream=*/nullptr);
   EXPECT_FALSE(tree.has_errors());
-  std::string print_output;
-  llvm::raw_string_ostream print_stream(print_output);
+  TestRawOstream print_stream;
   tree.Print(print_stream);
-  print_stream.flush();
 
   auto file = Yaml::SequenceValue{
       Yaml::MappingValue{{"kind", "FunctionIntroducer"}, {"text", "fn"}},
@@ -68,17 +67,15 @@ TEST_F(ParseTreeTest, PrintPostorderAsYAML) {
       Yaml::MappingValue{{"kind", "FileEnd"}, {"text", ""}},
   };
 
-  EXPECT_THAT(Yaml::Value::FromText(print_output), ElementsAre(file));
+  EXPECT_THAT(Yaml::Value::FromText(print_stream.TakeStr()), ElementsAre(file));
 }
 
 TEST_F(ParseTreeTest, PrintPreorderAsYAML) {
   TokenizedBuffer tokens = GetTokenizedBuffer("fn F();");
   ParseTree tree = ParseTree::Parse(tokens, consumer, /*vlog_stream=*/nullptr);
   EXPECT_FALSE(tree.has_errors());
-  std::string print_output;
-  llvm::raw_string_ostream print_stream(print_output);
+  TestRawOstream print_stream;
   tree.Print(print_stream, /*preorder=*/true);
-  print_stream.flush();
 
   auto parameter_list = Yaml::SequenceValue{
       Yaml::MappingValue{
@@ -107,7 +104,7 @@ TEST_F(ParseTreeTest, PrintPreorderAsYAML) {
           {"node_index", "5"}, {"kind", "FileEnd"}, {"text", ""}},
   };
 
-  EXPECT_THAT(Yaml::Value::FromText(print_output), ElementsAre(file));
+  EXPECT_THAT(Yaml::Value::FromText(print_stream.TakeStr()), ElementsAre(file));
 }
 
 TEST_F(ParseTreeTest, HighRecursion) {

toolchain/semantics/BUILD

@@ -105,6 +105,7 @@ cc_test(
     srcs = ["semantics_ir_test.cpp"],
     deps = [
         "//testing/util:gtest_main",
+        "//testing/util:test_raw_ostream",
         "//toolchain/common:yaml_test_helpers",
         "//toolchain/driver",
         "@com_google_googletest//:gtest",

toolchain/semantics/semantics_ir_test.cpp

@@ -10,6 +10,7 @@
 #include "llvm/Support/MemoryBuffer.h"
 #include "llvm/Support/VirtualFileSystem.h"
 #include "llvm/Support/raw_ostream.h"
+#include "testing/util/test_raw_ostream.h"
 #include "toolchain/common/yaml_test_helpers.h"
 #include "toolchain/driver/driver.h"
 
@@ -29,8 +30,7 @@ TEST(SemanticsIRTest, YAML) {
   llvm::vfs::InMemoryFileSystem fs;
   CARBON_CHECK(fs.addFile("test.carbon", /*ModificationTime=*/0,
                           llvm::MemoryBuffer::getMemBuffer("var x: i32 = 0;")));
-  std::string print_output;
-  llvm::raw_string_ostream print_stream(print_output);
+  TestRawOstream print_stream;
   Driver d(fs, print_stream, llvm::errs());
   d.RunFullCommand({"dump", "semantics-ir", "test.carbon"});
 
@@ -41,7 +41,7 @@ TEST(SemanticsIRTest, YAML) {
   auto type_id = Yaml::Scalar(MatchesRegex(R"(type\d+)"));
 
   EXPECT_THAT(
-      Yaml::Value::FromText(print_output),
+      Yaml::Value::FromText(print_stream.TakeStr()),
       ElementsAre(Yaml::Mapping(ElementsAre(
           Pair("cross_reference_irs_size", "1"),
           Pair("functions", Yaml::Sequence(IsEmpty())),