[Support][CommandLine] Make it possible to get error messages from ParseCommandLineOptions when ignoring errors.

Summary:
Previously, ParseCommandLineOptions returns false and ignores error messages
when IgnoreErrors. It would be useful to also return error messages if users
decide to check parsing result instead of having the program exit on error.

Reviewers: chandlerc, mehdi_amini, rnk

Reviewed By: rnk

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D30893

llvm-svn: 297810

1 files changed, 55 insertions, 21 deletions

diff --git a/llvm/unittests/Support/CommandLineTest.cpp b/llvm/unittests/Support/CommandLineTest.cpp
index 945eb1d4e1c..33573c4e696 100644
--- a/llvm/unittests/Support/CommandLineTest.cpp
+++ b/llvm/unittests/Support/CommandLineTest.cpp
@@ -303,7 +303,8 @@ TEST(CommandLineTest, SetValueInSubcategories) {
   EXPECT_FALSE(SC1Opt);
   EXPECT_FALSE(SC2Opt);
   const char *args[] = {"prog", "-top-level"};
-  EXPECT_TRUE(cl::ParseCommandLineOptions(2, args, StringRef(), true));
+  EXPECT_TRUE(
+      cl::ParseCommandLineOptions(2, args, StringRef(), &llvm::nulls()));
   EXPECT_TRUE(TopLevelOpt);
   EXPECT_FALSE(SC1Opt);
   EXPECT_FALSE(SC2Opt);
@@ -315,7 +316,8 @@ TEST(CommandLineTest, SetValueInSubcategories) {
   EXPECT_FALSE(SC1Opt);
   EXPECT_FALSE(SC2Opt);
   const char *args2[] = {"prog", "sc1", "-sc1"};
-  EXPECT_TRUE(cl::ParseCommandLineOptions(3, args2, StringRef(), true));
+  EXPECT_TRUE(
+      cl::ParseCommandLineOptions(3, args2, StringRef(), &llvm::nulls()));
   EXPECT_FALSE(TopLevelOpt);
   EXPECT_TRUE(SC1Opt);
   EXPECT_FALSE(SC2Opt);
@@ -327,7 +329,8 @@ TEST(CommandLineTest, SetValueInSubcategories) {
   EXPECT_FALSE(SC1Opt);
   EXPECT_FALSE(SC2Opt);
   const char *args3[] = {"prog", "sc2", "-sc2"};
-  EXPECT_TRUE(cl::ParseCommandLineOptions(3, args3, StringRef(), true));
+  EXPECT_TRUE(
+      cl::ParseCommandLineOptions(3, args3, StringRef(), &llvm::nulls()));
   EXPECT_FALSE(TopLevelOpt);
   EXPECT_FALSE(SC1Opt);
   EXPECT_TRUE(SC2Opt);
@@ -342,8 +345,13 @@ TEST(CommandLineTest, LookupFailsInWrongSubCommand) {
   StackOption<bool> SC1Opt("sc1", cl::sub(SC1), cl::init(false));
   StackOption<bool> SC2Opt("sc2", cl::sub(SC2), cl::init(false));
 
+  std::string Errs;
+  raw_string_ostream OS(Errs);
+
   const char *args[] = {"prog", "sc1", "-sc2"};
-  EXPECT_FALSE(cl::ParseCommandLineOptions(3, args, StringRef(), true));
+  EXPECT_FALSE(cl::ParseCommandLineOptions(3, args, StringRef(), &OS));
+  OS.flush();
+  EXPECT_FALSE(Errs.empty());
 }
 
 TEST(CommandLineTest, AddToAllSubCommands) {
@@ -358,23 +366,30 @@ TEST(CommandLineTest, AddToAllSubCommands) {
   const char *args2[] = {"prog", "sc1", "-everywhere"};
   const char *args3[] = {"prog", "sc2", "-everywhere"};
 
+  std::string Errs;
+  raw_string_ostream OS(Errs);
+
   EXPECT_FALSE(AllOpt);
-  EXPECT_TRUE(cl::ParseCommandLineOptions(2, args, StringRef(), true));
+  EXPECT_TRUE(cl::ParseCommandLineOptions(2, args, StringRef(), &OS));
   EXPECT_TRUE(AllOpt);
 
   AllOpt = false;
 
   cl::ResetAllOptionOccurrences();
   EXPECT_FALSE(AllOpt);
-  EXPECT_TRUE(cl::ParseCommandLineOptions(3, args2, StringRef(), true));
+  EXPECT_TRUE(cl::ParseCommandLineOptions(3, args2, StringRef(), &OS));
   EXPECT_TRUE(AllOpt);
 
   AllOpt = false;
 
   cl::ResetAllOptionOccurrences();
   EXPECT_FALSE(AllOpt);
-  EXPECT_TRUE(cl::ParseCommandLineOptions(3, args3, StringRef(), true));
+  EXPECT_TRUE(cl::ParseCommandLineOptions(3, args3, StringRef(), &OS));
   EXPECT_TRUE(AllOpt);
+
+  // Since all parsing succeeded, the error message should be empty.
+  OS.flush();
+  EXPECT_TRUE(Errs.empty());
 }
 
 TEST(CommandLineTest, ReparseCommandLineOptions) {
@@ -386,14 +401,16 @@ TEST(CommandLineTest, ReparseCommandLineOptions) {
   const char *args[] = {"prog", "-top-level"};
 
   EXPECT_FALSE(TopLevelOpt);
-  EXPECT_TRUE(cl::ParseCommandLineOptions(2, args, StringRef(), true));
+  EXPECT_TRUE(
+      cl::ParseCommandLineOptions(2, args, StringRef(), &llvm::nulls()));
   EXPECT_TRUE(TopLevelOpt);
 
   TopLevelOpt = false;
 
   cl::ResetAllOptionOccurrences();
   EXPECT_FALSE(TopLevelOpt);
-  EXPECT_TRUE(cl::ParseCommandLineOptions(2, args, StringRef(), true));
+  EXPECT_TRUE(
+      cl::ParseCommandLineOptions(2, args, StringRef(), &llvm::nulls()));
   EXPECT_TRUE(TopLevelOpt);
 }
 
@@ -406,14 +423,21 @@ TEST(CommandLineTest, RemoveFromRegularSubCommand) {
 
   const char *args[] = {"prog", "sc", "-remove-option"};
 
+  std::string Errs;
+  raw_string_ostream OS(Errs);
+
   EXPECT_FALSE(RemoveOption);
-  EXPECT_TRUE(cl::ParseCommandLineOptions(3, args, StringRef(), true));
+  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(), true));
+  EXPECT_FALSE(cl::ParseCommandLineOptions(3, args, StringRef(), &OS));
+  OS.flush();
+  EXPECT_FALSE(Errs.empty());
 }
 
 TEST(CommandLineTest, RemoveFromTopLevelSubCommand) {
@@ -427,13 +451,15 @@ TEST(CommandLineTest, RemoveFromTopLevelSubCommand) {
   const char *args[] = {"prog", "-top-level-remove"};
 
   EXPECT_FALSE(TopLevelRemove);
-  EXPECT_TRUE(cl::ParseCommandLineOptions(2, args, StringRef(), true));
+  EXPECT_TRUE(
+      cl::ParseCommandLineOptions(2, args, StringRef(), &llvm::nulls()));
   EXPECT_TRUE(TopLevelRemove);
 
   TopLevelRemove.removeArgument();
 
   cl::ResetAllOptionOccurrences();
-  EXPECT_FALSE(cl::ParseCommandLineOptions(2, args, StringRef(), true));
+  EXPECT_FALSE(
+      cl::ParseCommandLineOptions(2, args, StringRef(), &llvm::nulls()));
 }
 
 TEST(CommandLineTest, RemoveFromAllSubCommands) {
@@ -452,32 +478,38 @@ TEST(CommandLineTest, RemoveFromAllSubCommands) {
 
   // It should work for all subcommands including the top-level.
   EXPECT_FALSE(RemoveOption);
-  EXPECT_TRUE(cl::ParseCommandLineOptions(2, args0, StringRef(), true));
+  EXPECT_TRUE(
+      cl::ParseCommandLineOptions(2, args0, StringRef(), &llvm::nulls()));
   EXPECT_TRUE(RemoveOption);
 
   RemoveOption = false;
 
   cl::ResetAllOptionOccurrences();
   EXPECT_FALSE(RemoveOption);
-  EXPECT_TRUE(cl::ParseCommandLineOptions(3, args1, StringRef(), true));
+  EXPECT_TRUE(
+      cl::ParseCommandLineOptions(3, args1, StringRef(), &llvm::nulls()));
   EXPECT_TRUE(RemoveOption);
 
   RemoveOption = false;
 
   cl::ResetAllOptionOccurrences();
   EXPECT_FALSE(RemoveOption);
-  EXPECT_TRUE(cl::ParseCommandLineOptions(3, args2, StringRef(), true));
+  EXPECT_TRUE(
+      cl::ParseCommandLineOptions(3, args2, StringRef(), &llvm::nulls()));
   EXPECT_TRUE(RemoveOption);
 
   RemoveOption.removeArgument();
 
   // It should not work for any subcommands including the top-level.
   cl::ResetAllOptionOccurrences();
-  EXPECT_FALSE(cl::ParseCommandLineOptions(2, args0, StringRef(), true));
+  EXPECT_FALSE(
+      cl::ParseCommandLineOptions(2, args0, StringRef(), &llvm::nulls()));
   cl::ResetAllOptionOccurrences();
-  EXPECT_FALSE(cl::ParseCommandLineOptions(3, args1, StringRef(), true));
+  EXPECT_FALSE(
+      cl::ParseCommandLineOptions(3, args1, StringRef(), &llvm::nulls()));
   cl::ResetAllOptionOccurrences();
-  EXPECT_FALSE(cl::ParseCommandLineOptions(3, args2, StringRef(), true));
+  EXPECT_FALSE(
+      cl::ParseCommandLineOptions(3, args2, StringRef(), &llvm::nulls()));
 }
 
 TEST(CommandLineTest, GetRegisteredSubcommands) {
@@ -491,7 +523,8 @@ TEST(CommandLineTest, GetRegisteredSubcommands) {
   const char *args0[] = {"prog", "sc1"};
   const char *args1[] = {"prog", "sc2"};
 
-  EXPECT_TRUE(cl::ParseCommandLineOptions(2, args0, StringRef(), true));
+  EXPECT_TRUE(
+      cl::ParseCommandLineOptions(2, args0, StringRef(), &llvm::nulls()));
   EXPECT_FALSE(Opt1);
   EXPECT_FALSE(Opt2);
   for (auto *S : cl::getRegisteredSubcommands()) {
@@ -500,7 +533,8 @@ TEST(CommandLineTest, GetRegisteredSubcommands) {
   }
 
   cl::ResetAllOptionOccurrences();
-  EXPECT_TRUE(cl::ParseCommandLineOptions(2, args1, StringRef(), true));
+  EXPECT_TRUE(
+      cl::ParseCommandLineOptions(2, args1, StringRef(), &llvm::nulls()));
   EXPECT_FALSE(Opt1);
   EXPECT_FALSE(Opt2);
   for (auto *S : cl::getRegisteredSubcommands()) {