[llvm] [CommandLine] Add subcommand groups (PR #75678)

[Igor Kudrin via llvm-commits]

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@@ -2274,4 +2274,67 @@ TEST(CommandLineTest, UnknownCommands) {
   EXPECT_EQ(Errs, "prog: Unknown subcommand 'faz'.  Try: 'prog --help'\n");
 }
 
+TEST(CommandLineTest, SubCommandGroups) {
+  cl::ResetCommandLineParser();
+
+  StackSubCommand SC1("sc1", "SC1 subcommand");
+  StackSubCommand SC2("sc2", "SC2 subcommand");
+  StackSubCommand SC3("sc3", "SC3 subcommand");
+  cl::SubCommandGroup Group12 = {&SC1, &SC2};
+  cl::SubCommandGroup Group23 = {&SC2, &SC3};
+
+  StackOption<bool> Opt1("opt1", cl::sub(SC1), cl::init(false));
+  StackOption<bool> Opt2("opt2", cl::sub(SC2), cl::init(false));
+  StackOption<bool> Opt3("opt3", cl::sub(SC3), cl::init(false));
+  StackOption<bool> Opt12("opt12", cl::sub(Group12), cl::init(false));
+  StackOption<bool> Opt23("opt23", cl::sub(Group23), cl::init(false));
+
+  EXPECT_EQ(2, SC1.OptionsMap.size());
+  EXPECT_TRUE(SC1.OptionsMap.contains("opt1"));
+  EXPECT_TRUE(SC1.OptionsMap.contains("opt12"));
+
+  EXPECT_EQ(3, SC2.OptionsMap.size());
+  EXPECT_TRUE(SC2.OptionsMap.contains("opt2"));
+  EXPECT_TRUE(SC2.OptionsMap.contains("opt12"));
+  EXPECT_TRUE(SC2.OptionsMap.contains("opt23"));
+
+  EXPECT_EQ(2, SC3.OptionsMap.size());
+  EXPECT_TRUE(SC3.OptionsMap.contains("opt3"));
+  EXPECT_TRUE(SC3.OptionsMap.contains("opt23"));
+
+  const char *Args1[] = {"prog", "--opt1"};
+  EXPECT_FALSE(cl::ParseCommandLineOptions(std::size(Args1), Args1, StringRef(),
+                                           &llvm::nulls()));
+
+  cl::ResetAllOptionOccurrences();
+
+  const char *Args2[] = {"prog", "sc2", "--opt2"};
+  EXPECT_TRUE(cl::ParseCommandLineOptions(std::size(Args2), Args2, StringRef(),
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igorkudrin wrote:

I have simplified the test and added some comments. Is it better now? It doesn't seem to me that this tiny feature deserves its own test fixture.

https://github.com/llvm/llvm-project/pull/75678