[llvm][unittests] Don't call raw_string_ostream::flush() (NFC)

raw_string_ostream::flush() is essentially a no-op (also specified in docs).
Don't call it in tests that aren't meant to test 'raw_string_ostream' itself.

p.s. remove a few redundant calls to raw_string_ostream::str()

llvm/unittests/ADT/RewriteBufferTest.cpp

@@ -19,7 +19,6 @@ static std::string writeOutput(const RewriteBuffer &Buf) {
   std::string Result;
   raw_string_ostream OS(Result);
   Buf.write(OS);
-  OS.flush();
   return Result;
 }
 

llvm/unittests/DebugInfo/DWARF/DWARFDebugFrameTest.cpp

@@ -44,7 +44,6 @@ void expectDumpResult(const dwarf::CIE &TestCIE, bool IsEH,
   auto DumpOpts = DIDumpOptions();
   DumpOpts.IsEH = IsEH;
   TestCIE.dump(OS, DumpOpts);
-  OS.flush();
   StringRef FirstLine = StringRef(Output).split('\n').first;
   EXPECT_EQ(FirstLine, ExpectedFirstLine);
 }
@@ -56,7 +55,6 @@ void expectDumpResult(const dwarf::FDE &TestFDE, bool IsEH,
   auto DumpOpts = DIDumpOptions();
   DumpOpts.IsEH = IsEH;
   TestFDE.dump(OS, DumpOpts);
-  OS.flush();
   StringRef FirstLine = StringRef(Output).split('\n').first;
   EXPECT_EQ(FirstLine, ExpectedFirstLine);
 }
@@ -344,7 +342,6 @@ void expectDumpResult(const dwarf::UnwindLocation &Loc,
   std::string Output;
   raw_string_ostream OS(Output);
   OS << Loc;
-  OS.flush();
   StringRef FirstLine = StringRef(Output).split('\n').first;
   EXPECT_EQ(FirstLine, ExpectedFirstLine);
 }
@@ -387,7 +384,6 @@ void expectDumpResult(const dwarf::RegisterLocations &Locs,
   std::string Output;
   raw_string_ostream OS(Output);
   OS << Locs;
-  OS.flush();
   StringRef FirstLine = StringRef(Output).split('\n').first;
   EXPECT_EQ(FirstLine, ExpectedFirstLine);
 }

llvm/unittests/DebugInfo/DWARF/DWARFDebugLineTest.cpp

@@ -1558,7 +1558,6 @@ TEST_F(DebugLineBasicFixture, VerboseOutput) {
   raw_string_ostream OS(Output);
   Parser.parseNext(RecordRecoverable, RecordUnrecoverable, &OS,
                    /*Verbose=*/true);
-  OS.flush();
   StringRef OutputRef(Output);
 
   size_t Pos = 0;
@@ -1805,7 +1804,6 @@ struct TruncatedOpcodeFixtureBase : public CommonFixture {
     raw_string_ostream OS(Output);
     Parser.parseNext(RecordRecoverable, RecordUnrecoverable, &OS,
                      /*Verbose=*/true);
-    OS.flush();
 
     std::string LinePrefix =
         ("0x0000002f: 0" + Twine::utohexstr(OpcodeValue) + " ").str();

llvm/unittests/DebugInfo/DWARF/DWARFFormValueTest.cpp

@@ -375,7 +375,6 @@ TEST_P(DumpValueFixture, Test) {
   Opts.ShowAddresses = true;
 
   Form.dump(OS, Opts);
-  OS.flush();
 
   EXPECT_EQ(Output, ExpectedResult);
 }

llvm/unittests/DebugInfo/GSYM/GSYMTest.cpp

@@ -3802,7 +3802,6 @@ TEST(GSYMTest, TestRangeWarnings) {
   const uint32_t ThreadCount = 1;
   ASSERT_THAT_ERROR(DT.convert(ThreadCount, OSAgg), Succeeded());
   ASSERT_THAT_ERROR(GC.finalize(OSAgg), Succeeded());
-  OS.flush();
   SmallString<512> Str;
   raw_svector_ostream OutStrm(Str);
   const auto ByteOrder = llvm::endianness::native;
@@ -4005,7 +4004,6 @@ TEST(GSYMTest, TestEmptyRangeWarnings) {
   const uint32_t ThreadCount = 1;
   ASSERT_THAT_ERROR(DT.convert(ThreadCount, OSAgg), Succeeded());
   ASSERT_THAT_ERROR(GC.finalize(OSAgg), Succeeded());
-  OS.flush();
   SmallString<512> Str;
   raw_svector_ostream OutStrm(Str);
   const auto ByteOrder = llvm::endianness::native;
@@ -4158,7 +4156,6 @@ TEST(GSYMTest, TestEmptyLinkageName) {
   const uint32_t ThreadCount = 1;
   ASSERT_THAT_ERROR(DT.convert(ThreadCount, OSAgg), Succeeded());
   ASSERT_THAT_ERROR(GC.finalize(OSAgg), Succeeded());
-  OS.flush();
   SmallString<512> Str;
   raw_svector_ostream OutStrm(Str);
   const auto ByteOrder = llvm::endianness::native;
@@ -4320,7 +4317,6 @@ TEST(GSYMTest, TestLineTablesWithEmptyRanges) {
   const uint32_t ThreadCount = 1;
   ASSERT_THAT_ERROR(DT.convert(ThreadCount, OSAgg), Succeeded());
   ASSERT_THAT_ERROR(GC.finalize(OSAgg), Succeeded());
-  OS.flush();
   SmallString<512> Str;
   raw_svector_ostream OutStrm(Str);
   const auto ByteOrder = llvm::endianness::native;
@@ -4641,7 +4637,6 @@ TEST(GSYMTest, TestHandlingOfInvalidFileIndexes) {
   const uint32_t ThreadCount = 1;
   ASSERT_THAT_ERROR(DT.convert(ThreadCount, OSAgg), Succeeded());
   ASSERT_THAT_ERROR(GC.finalize(OSAgg), Succeeded());
-  OS.flush();
   SmallString<512> Str;
   raw_svector_ostream OutStrm(Str);
   const auto ByteOrder = llvm::endianness::native;
@@ -4857,7 +4852,6 @@ TEST(GSYMTest, TestLookupsOfOverlappingAndUnequalRanges) {
   const uint32_t ThreadCount = 1;
   ASSERT_THAT_ERROR(DT.convert(ThreadCount, OSAgg), Succeeded());
   ASSERT_THAT_ERROR(GC.finalize(OSAgg), Succeeded());
-  OS.flush();
   SmallString<512> Str;
   raw_svector_ostream OutStrm(Str);
   const auto ByteOrder = llvm::endianness::native;

llvm/unittests/IR/ConstantsTest.cpp

@@ -172,7 +172,6 @@ TEST(ConstantsTest, PointerCast) {
     Instruction *__I = cast<ConstantExpr>(x)->getAsInstruction();              \
     __I->print(__o);                                                           \
     __I->deleteValue();                                                        \
-    __o.flush();                                                               \
     EXPECT_EQ(std::string("  <badref> = " y), __s);                            \
   }
 

llvm/unittests/IR/ManglerTest.cpp

@@ -20,7 +20,6 @@ static std::string mangleStr(StringRef IRName, Mangler &Mang,
   std::string Mangled;
   raw_string_ostream SS(Mangled);
   Mang.getNameWithPrefix(SS, IRName, DL);
-  SS.flush();
   return Mangled;
 }
 
@@ -37,7 +36,6 @@ static std::string mangleFunc(StringRef IRName,
   std::string Mangled;
   raw_string_ostream SS(Mangled);
   Mang.getNameWithPrefix(SS, F, false);
-  SS.flush();
   F->eraseFromParent();
   return Mangled;
 }

llvm/unittests/IR/MetadataTest.cpp

@@ -299,7 +299,6 @@ TEST_F(MDNodeTest, Print) {
     std::string Actual_;                                                       \
     raw_string_ostream OS(Actual_);                                            \
     PRINT;                                                                     \
-    OS.flush();                                                                \
     std::string Expected_(EXPECTED);                                           \
     EXPECT_EQ(Expected_, Actual_);                                             \
   } while (false)

llvm/unittests/IR/ModuleSummaryIndexTest.cpp

@@ -45,7 +45,6 @@ TEST(ModuleSummaryIndexTest, MemProfSummaryPrinting) {
   for (auto &AI : AllocSummary->allocs())
     OS << "\n" << AI;
 
-  OS.flush();
   EXPECT_EQ(Data, R"(
 Callee: 23 Clones: 0 StackIds: 2, 3
 Callee: 23 Clones: 0 StackIds: 2, 4

llvm/unittests/MC/MCInstPrinter.cpp

@@ -53,7 +53,6 @@ class MCInstPrinterTest : public ::testing::Test {
     std::string Buffer;
     raw_string_ostream OS(Buffer);
     OS << Printer->formatHex(i);
-    OS.flush();
     return Buffer;
   }
 };

llvm/unittests/MIR/MachineMetadata.cpp

@@ -106,7 +106,6 @@ static std::string print(std::function<void(raw_ostream &OS)> PrintFn) {
   std::string Str;
   raw_string_ostream OS(Str);
   PrintFn(OS);
-  OS.flush();
   return Str;
 }
 

llvm/unittests/Object/SymbolicFileTest.cpp

@@ -35,7 +35,6 @@ TEST(Object, DataRefImplOstream) {
   }
 
   OS << Data;
-  OS.flush();
 
   EXPECT_EQ(Expected, s);
 }

llvm/unittests/ProfileData/InstrProfTest.cpp

@@ -431,7 +431,6 @@ MATCHER_P(EqualsRecord, Want, "") {
     Want.print(OS);
     OS << "Got:\n";
     Got.print(OS);
-    OS.flush();
     *result_listener << "MemProf Record differs!\n" << Buffer;
     return false;
   };

llvm/unittests/ProfileData/MemProfTest.cpp

@@ -255,7 +255,6 @@ TEST(MemProf, PortableWrapper) {
   std::string Buffer;
   llvm::raw_string_ostream OS(Buffer);
   WriteBlock.serialize(Schema, OS);
-  OS.flush();
 
   PortableMemInfoBlock ReadBlock(
       Schema, reinterpret_cast<const unsigned char *>(Buffer.data()));
@@ -296,7 +295,6 @@ TEST(MemProf, RecordSerializationRoundTripVersion0And1) {
   std::string Buffer;
   llvm::raw_string_ostream OS(Buffer);
   Record.serialize(Schema, OS, llvm::memprof::Version0);
-  OS.flush();
 
   const IndexedMemProfRecord GotRecord = IndexedMemProfRecord::deserialize(
       Schema, reinterpret_cast<const unsigned char *>(Buffer.data()),
@@ -326,7 +324,6 @@ TEST(MemProf, RecordSerializationRoundTripVerion2) {
   std::string Buffer;
   llvm::raw_string_ostream OS(Buffer);
   Record.serialize(Schema, OS, llvm::memprof::Version2);
-  OS.flush();
 
   const IndexedMemProfRecord GotRecord = IndexedMemProfRecord::deserialize(
       Schema, reinterpret_cast<const unsigned char *>(Buffer.data()),
@@ -378,7 +375,6 @@ TEST(MemProf, RecordSerializationRoundTripVersion2HotColdSchema) {
   std::string Buffer;
   llvm::raw_string_ostream OS(Buffer);
   Record.serialize(Schema, OS, llvm::memprof::Version2);
-  OS.flush();
 
   const IndexedMemProfRecord GotRecord = IndexedMemProfRecord::deserialize(
       Schema, reinterpret_cast<const unsigned char *>(Buffer.data()),

llvm/unittests/Support/CommandLineTest.cpp

@@ -520,7 +520,6 @@ TEST(CommandLineTest, LookupFailsInWrongSubCommand) {
 
   const char *args[] = {"prog", "sc1", "-sc2"};
   EXPECT_FALSE(cl::ParseCommandLineOptions(3, args, StringRef(), &OS));
-  OS.flush();
   EXPECT_FALSE(Errs.empty());
 }
 
@@ -616,7 +615,6 @@ TEST(CommandLineTest, AddToAllSubCommands) {
   EXPECT_TRUE(AllOpt);
 
   // Since all parsing succeeded, the error message should be empty.
-  OS.flush();
   EXPECT_TRUE(Errs.empty());
 }
 
@@ -657,14 +655,12 @@ TEST(CommandLineTest, RemoveFromRegularSubCommand) {
   EXPECT_FALSE(RemoveOption);
   EXPECT_TRUE(cl::ParseCommandLineOptions(3, args, StringRef(), &OS));
   EXPECT_TRUE(RemoveOption);
-  OS.flush();
   EXPECT_TRUE(Errs.empty());
 
   RemoveOption.removeArgument();
 
   cl::ResetAllOptionOccurrences();
   EXPECT_FALSE(cl::ParseCommandLineOptions(3, args, StringRef(), &OS));
-  OS.flush();
   EXPECT_FALSE(Errs.empty());
 }
 
@@ -1277,15 +1273,15 @@ TEST(CommandLineTest, PositionalEatArgsError) {
 
   std::string Errs;
   raw_string_ostream OS(Errs);
-  EXPECT_FALSE(cl::ParseCommandLineOptions(2, args, StringRef(), &OS)); OS.flush();
+  EXPECT_FALSE(cl::ParseCommandLineOptions(2, args, StringRef(), &OS));
   EXPECT_FALSE(Errs.empty()); Errs.clear();
-  EXPECT_FALSE(cl::ParseCommandLineOptions(3, args2, StringRef(), &OS)); OS.flush();
+  EXPECT_FALSE(cl::ParseCommandLineOptions(3, args2, StringRef(), &OS));
   EXPECT_FALSE(Errs.empty()); Errs.clear();
-  EXPECT_TRUE(cl::ParseCommandLineOptions(3, args3, StringRef(), &OS)); OS.flush();
+  EXPECT_TRUE(cl::ParseCommandLineOptions(3, args3, StringRef(), &OS));
   EXPECT_TRUE(Errs.empty()); Errs.clear();
 
   cl::ResetAllOptionOccurrences();
-  EXPECT_TRUE(cl::ParseCommandLineOptions(6, args4, StringRef(), &OS)); OS.flush();
+  EXPECT_TRUE(cl::ParseCommandLineOptions(6, args4, StringRef(), &OS));
   EXPECT_EQ(PosEatArgs.size(), 1u);
   EXPECT_EQ(PosEatArgs2.size(), 2u);
   EXPECT_TRUE(Errs.empty());
@@ -1875,15 +1871,15 @@ TEST(CommandLineTest, LongOptions) {
   //
 
   EXPECT_TRUE(
-      cl::ParseCommandLineOptions(4, args1, StringRef(), &OS)); OS.flush();
+      cl::ParseCommandLineOptions(4, args1, StringRef(), &OS));
   EXPECT_TRUE(OptA);
   EXPECT_FALSE(OptBLong);
   EXPECT_STREQ("val1", OptAB.c_str());
   EXPECT_TRUE(Errs.empty()); Errs.clear();
   cl::ResetAllOptionOccurrences();
 
   EXPECT_TRUE(
-      cl::ParseCommandLineOptions(4, args2, StringRef(), &OS)); OS.flush();
+      cl::ParseCommandLineOptions(4, args2, StringRef(), &OS));
   EXPECT_TRUE(OptA);
   EXPECT_FALSE(OptBLong);
   EXPECT_STREQ("val1", OptAB.c_str());
@@ -1893,7 +1889,7 @@ TEST(CommandLineTest, LongOptions) {
   // Fails because `-ab` and `--ab` are treated the same and appear more than
   // once.  Also, `val1` is unexpected.
   EXPECT_FALSE(
-      cl::ParseCommandLineOptions(4, args3, StringRef(), &OS)); OS.flush();
+      cl::ParseCommandLineOptions(4, args3, StringRef(), &OS));
   outs()<< Errs << "\n";
   EXPECT_FALSE(Errs.empty()); Errs.clear();
   cl::ResetAllOptionOccurrences();
@@ -1906,13 +1902,13 @@ TEST(CommandLineTest, LongOptions) {
   // Fails because `-ab` is treated as `-a -b`, so `-a` is seen twice, and
   // `val1` is unexpected.
   EXPECT_FALSE(cl::ParseCommandLineOptions(4, args1, StringRef(),
-                                           &OS, nullptr, true)); OS.flush();
+                                           &OS, nullptr, true));
   EXPECT_FALSE(Errs.empty()); Errs.clear();
   cl::ResetAllOptionOccurrences();
 
   // Works because `-a` is treated differently than `--ab`.
   EXPECT_TRUE(cl::ParseCommandLineOptions(4, args2, StringRef(),
-                                           &OS, nullptr, true)); OS.flush();
+                                           &OS, nullptr, true));
   EXPECT_TRUE(Errs.empty()); Errs.clear();
   cl::ResetAllOptionOccurrences();
 
@@ -1922,7 +1918,6 @@ TEST(CommandLineTest, LongOptions) {
   EXPECT_TRUE(OptA);
   EXPECT_TRUE(OptBLong);
   EXPECT_STREQ("val1", OptAB.c_str());
-  OS.flush();
   EXPECT_TRUE(Errs.empty()); Errs.clear();
   cl::ResetAllOptionOccurrences();
 }
@@ -1941,12 +1936,10 @@ TEST(CommandLineTest, OptionErrorMessage) {
   raw_string_ostream OS(Errs);
 
   OptA.error("custom error", OS);
-  OS.flush();
   EXPECT_NE(Errs.find("for the -a option:"), std::string::npos);
   Errs.clear();
 
   OptLong.error("custom error", OS);
-  OS.flush();
   EXPECT_NE(Errs.find("for the --long option:"), std::string::npos);
   Errs.clear();
 
@@ -1969,7 +1962,6 @@ TEST(CommandLineTest, OptionErrorMessageSuggest) {
   raw_string_ostream OS(Errs);
 
   EXPECT_FALSE(cl::ParseCommandLineOptions(2, args, StringRef(), &OS));
-  OS.flush();
   EXPECT_NE(Errs.find("prog: Did you mean '--aluminium'?\n"),
             std::string::npos);
   Errs.clear();
@@ -1992,7 +1984,6 @@ TEST(CommandLineTest, OptionErrorMessageSuggestNoHidden) {
   raw_string_ostream OS(Errs);
 
   EXPECT_FALSE(cl::ParseCommandLineOptions(2, args, StringRef(), &OS));
-  OS.flush();
   EXPECT_NE(Errs.find("prog: Did you mean '--aluminium'?\n"),
             std::string::npos);
   Errs.clear();
@@ -2082,7 +2073,6 @@ TEST(CommandLineTest, ConsumeAfterOnePositional) {
   std::string Errs;
   raw_string_ostream OS(Errs);
   EXPECT_TRUE(cl::ParseCommandLineOptions(4, Args, StringRef(), &OS));
-  OS.flush();
   EXPECT_EQ("input", Input);
   EXPECT_EQ(ExtraArgs.size(), 2u);
   EXPECT_EQ(ExtraArgs[0], "arg1");
@@ -2105,7 +2095,6 @@ TEST(CommandLineTest, ConsumeAfterTwoPositionals) {
   std::string Errs;
   raw_string_ostream OS(Errs);
   EXPECT_TRUE(cl::ParseCommandLineOptions(5, Args, StringRef(), &OS));
-  OS.flush();
   EXPECT_EQ("input1", Input1);
   EXPECT_EQ("input2", Input2);
   EXPECT_EQ(ExtraArgs.size(), 2u);

llvm/unittests/Support/CrashRecoveryTest.cpp

@@ -111,8 +111,7 @@ TEST(CrashRecoveryTest, LimitedStackTrace) {
   std::string Res;
   llvm::raw_string_ostream RawStream(Res);
   PrintStackTrace(RawStream, 1);
-  std::string Str = RawStream.str();
-  EXPECT_EQ(std::string::npos, Str.find("#1"));
+  EXPECT_EQ(std::string::npos, Res.find("#1"));
 }
 
 #ifdef _WIN32

llvm/unittests/Support/ErrorTest.cpp

@@ -460,13 +460,11 @@ TEST(Error, createStringError) {
   EXPECT_EQ(Msg, "foobar10xff\n")
       << "Unexpected createStringError() log result";
 
-  S.flush();
   Msg.clear();
   logAllUnhandledErrors(createStringError(EC, Bar), S);
   EXPECT_EQ(Msg, "bar\n")
       << "Unexpected createStringError() (overloaded) log result";
 
-  S.flush();
   Msg.clear();
   auto Res = errorToErrorCode(createStringError(EC, "foo%s", Bar));
   EXPECT_EQ(Res, EC)

llvm/unittests/Support/FormatVariadicTest.cpp

@@ -585,7 +585,6 @@ TEST(FormatVariadicTest, BigTest) {
   for (auto &Item : Ts) {
     Stream << std::apply(format_tuple(Line), Item) << "\n";
   }
-  Stream.flush();
   const char *Expected =
       R"foo(There are {14} items in the tuple, and {2} tuple(s) in the array.
   Char|  HexInt|   Str    |   Ref    |  std::str   | double|  float|   pointer|comma  |       exp|          bigint|          bigint2| limit|byte