[Tooling] Add operator== to CompileCommand

[simark]

Summary

It does the obvious thing of comparing all fields. This will be needed
for a clangd patch I have in the pipeline.

[dblaikie]

Any chance this can/should be unit tested? (also, in general (though might
not matter in this instance), symmetric operators like == should be
implemented as non-members (though they can still be friends and if they
are, can be defined inline in the class definition as a member could be),
so any implicit conversions apply equally to the LHS as the RHS of the
expression)

[simark]

In D49265#1163740, @dblaikie wrote:

Any chance this can/should be unit tested? (also, in general (though might
not matter in this instance), symmetric operators like == should be
implemented as non-members (though they can still be friends and if they
are, can be defined inline in the class definition as a member could be),
so any implicit conversions apply equally to the LHS as the RHS of the
expression)

Of course, I'm on it.

[simark]

• Add test
• Make operator== a function instead of method
• Add operator!= (so I can use EXPECT_NE in the test, and because it may be useful in general)

[dblaikie]

In theory you'd need separate tests for op== and op!= returning false (currently all the tests would pass if both implementations returned true in all cases), but not the biggest deal.

[simark]

In D49265#1164227, @dblaikie wrote:

In theory you'd need separate tests for op== and op!= returning false (currently all the tests would pass if both implementations returned true in all cases), but not the biggest deal.

Good point, I'll update it, it will take a second.

[simark]

Add tests for both == and !=.

I need to rebuild ~800 files (because I pulled llvm/clang), so I did not
actually test it, but I'll do so before pushing tomorrow, of course.

[dblaikie]

Looks good, Thanks!

include/clang/Tooling/CompilationDatabase.h

struct CompileCommand {
   /// The source file associated with the command.
   std::string Filename;
 
   /// The command line that was executed.
   std::vector<std::string> CommandLine;
 
   /// The output file associated with the command.
   std::string Output;
+
+  friend bool operator==(const CompileCommand &LHS, const CompileCommand &RHS) {
+    return LHS.Directory == RHS.Directory && LHS.Filename == RHS.Filename &&
+           LHS.CommandLine == RHS.CommandLine && LHS.Output == RHS.Output;
+  }
+
+  friend bool operator!=(const CompileCommand &LHS, const CompileCommand &RHS) {
+    return !(LHS == RHS);
+  }
 };
 
 /// Interface for compilation databases.
 ///
 /// A compilation database allows the user to retrieve compile command lines
 /// for the files in a project.
 ///
 /// Many implementations are enumerable, allowing all command lines to be

unittests/Tooling/CompilationDatabaseTest.cpp

 
 TEST_F(InterpolateTest, Case) {
   add("FOO/BAR/BAZ/SHOUT.cc");
   add("foo/bar/baz/quiet.cc");
   // Case mismatches are completely ignored, so we choose the name match.
   EXPECT_EQ(getCommand("foo/bar/baz/shout.C"), "clang -D FOO/BAR/BAZ/SHOUT.cc");
 }
 
+TEST(CompileCommandTest, EqualityOperator) {
+  CompileCommand CCRef("/foo/bar", "hello.c", {"a", "b"}, "hello.o");
+  CompileCommand CCTest = CCRef;
+
+  EXPECT_TRUE(CCRef == CCTest);
+  EXPECT_FALSE(CCRef != CCTest);
+
+  CCTest = CCRef;
+  CCTest.Directory = "/foo/baz";
+  EXPECT_FALSE(CCRef == CCTest);
+  EXPECT_TRUE(CCRef != CCTest);
+
+  CCTest = CCRef;
+  CCTest.Filename = "bonjour.c";
+  EXPECT_FALSE(CCRef == CCTest);
+  EXPECT_TRUE(CCRef != CCTest);
+
+  CCTest = CCRef;
+  CCTest.CommandLine.push_back("c");
+  EXPECT_FALSE(CCRef == CCTest);
+  EXPECT_TRUE(CCRef != CCTest);
+
+  CCTest = CCRef;
+  CCTest.Output = "bonjour.o";
+  EXPECT_FALSE(CCRef == CCTest);
+  EXPECT_TRUE(CCRef != CCTest);
+}
+
 } // end namespace tooling
 } // end namespace clang