Add support for prefix-only CLI options

Summary:
Add support for options that always prefix their value, giving an error
if the value is in the next argument or if the option is given a value
assignment (ie. opt=val). This is the desired behavior for the -D option
of FileCheck for instance.

Copyright:
- Linaro (changes in version 2 of revision D55940)
- GraphCore (changes in later versions and introduced when creating
  D56549)

Reviewers: jdenny

Subscribers: llvm-commits, probinson, kristina, hiraditya,
JonChesterfield

Differential Revision: https://reviews.llvm.org/D56549

llvm-svn: 351038

1 files changed, 75 insertions, 1 deletions

diff --git a/llvm/unittests/Support/CommandLineTest.cpp b/llvm/unittests/Support/CommandLineTest.cpp
index a296912a305..9d06f7265a7 100644
--- a/llvm/unittests/Support/CommandLineTest.cpp
+++ b/llvm/unittests/Support/CommandLineTest.cpp
@@ -840,4 +840,78 @@ TEST(CommandLineTest, GetCommandLineArguments) {
 }
 #endif
 
-}  // anonymous namespace
+TEST(CommandLineTest, PrefixOptions) {
+  cl::ResetCommandLineParser();
+
+  StackOption<std::string, cl::list<std::string>> IncludeDirs(
+      "I", cl::Prefix, cl::desc("Declare an include directory"));
+
+  // Test non-prefixed variant works with cl::Prefix options.
+  EXPECT_TRUE(IncludeDirs.empty());
+  const char *args[] = {"prog", "-I=/usr/include"};
+  EXPECT_TRUE(
+      cl::ParseCommandLineOptions(2, args, StringRef(), &llvm::nulls()));
+  EXPECT_TRUE(IncludeDirs.size() == 1);
+  EXPECT_TRUE(IncludeDirs.front().compare("/usr/include") == 0);
+
+  IncludeDirs.erase(IncludeDirs.begin());
+  cl::ResetAllOptionOccurrences();
+
+  // Test non-prefixed variant works with cl::Prefix options when value is
+  // passed in following argument.
+  EXPECT_TRUE(IncludeDirs.empty());
+  const char *args2[] = {"prog", "-I", "/usr/include"};
+  EXPECT_TRUE(
+      cl::ParseCommandLineOptions(3, args2, StringRef(), &llvm::nulls()));
+  EXPECT_TRUE(IncludeDirs.size() == 1);
+  EXPECT_TRUE(IncludeDirs.front().compare("/usr/include") == 0);
+
+  IncludeDirs.erase(IncludeDirs.begin());
+  cl::ResetAllOptionOccurrences();
+
+  // Test prefixed variant works with cl::Prefix options.
+  EXPECT_TRUE(IncludeDirs.empty());
+  const char *args3[] = {"prog", "-I/usr/include"};
+  EXPECT_TRUE(
+      cl::ParseCommandLineOptions(2, args3, StringRef(), &llvm::nulls()));
+  EXPECT_TRUE(IncludeDirs.size() == 1);
+  EXPECT_TRUE(IncludeDirs.front().compare("/usr/include") == 0);
+
+  StackOption<std::string, cl::list<std::string>> MacroDefs(
+      "D", cl::AlwaysPrefix, cl::desc("Define a macro"),
+      cl::value_desc("MACRO[=VALUE]"));
+
+  cl::ResetAllOptionOccurrences();
+
+  // Test non-prefixed variant does not work with cl::AlwaysPrefix options:
+  // equal sign is part of the value.
+  EXPECT_TRUE(MacroDefs.empty());
+  const char *args4[] = {"prog", "-D=HAVE_FOO"};
+  EXPECT_TRUE(
+      cl::ParseCommandLineOptions(2, args4, StringRef(), &llvm::nulls()));
+  EXPECT_TRUE(MacroDefs.size() == 1);
+  EXPECT_TRUE(MacroDefs.front().compare("=HAVE_FOO") == 0);
+
+  MacroDefs.erase(MacroDefs.begin());
+  cl::ResetAllOptionOccurrences();
+
+  // Test non-prefixed variant does not allow value to be passed in following
+  // argument with cl::AlwaysPrefix options.
+  EXPECT_TRUE(MacroDefs.empty());
+  const char *args5[] = {"prog", "-D", "HAVE_FOO"};
+  EXPECT_FALSE(
+      cl::ParseCommandLineOptions(3, args5, StringRef(), &llvm::nulls()));
+  EXPECT_TRUE(MacroDefs.empty());
+
+  cl::ResetAllOptionOccurrences();
+
+  // Test prefixed variant works with cl::AlwaysPrefix options.
+  EXPECT_TRUE(MacroDefs.empty());
+  const char *args6[] = {"prog", "-DHAVE_FOO"};
+  EXPECT_TRUE(
+      cl::ParseCommandLineOptions(2, args6, StringRef(), &llvm::nulls()));
+  EXPECT_TRUE(MacroDefs.size() == 1);
+  EXPECT_TRUE(MacroDefs.front().compare("HAVE_FOO") == 0);
+}
+
+} // anonymous namespace