[tooling] Provide the compile commands of the JSON database in the order that they were provided in the JSON file.

This is useful for debugging of issues and reduction of test cases.
For example, an issue may show up due to the order that some commands were processed.
It is convenient to be able to remove commands from the file and still preserve the order
that they are returned, instead of getting a completely different order when removing a few commands.

llvm-svn: 248292

3 files changed, 27 insertions, 7 deletions

diff --git a/clang/include/clang/Tooling/JSONCompilationDatabase.h b/clang/include/clang/Tooling/JSONCompilationDatabase.h
index 0e6c893..2a13fc1 100644
--- a/clang/include/clang/Tooling/JSONCompilationDatabase.h
+++ b/clang/include/clang/Tooling/JSONCompilationDatabase.h
@@ -116,6 +116,10 @@ private:
   // Maps file paths to the compile command lines for that file.
   llvm::StringMap<std::vector<CompileCommandRef>> IndexByFile;
 
+  /// All the compile commands in the order that they were provided in the
+  /// JSON stream.
+  std::vector<CompileCommandRef> AllCommands;
+
   FileMatchTrie MatchTrie;
 
   std::unique_ptr<llvm::MemoryBuffer> Database;
diff --git a/clang/lib/Tooling/JSONCompilationDatabase.cpp b/clang/lib/Tooling/JSONCompilationDatabase.cpp
index dd4d7a8..299fbdc 100644
--- a/clang/lib/Tooling/JSONCompilationDatabase.cpp
+++ b/clang/lib/Tooling/JSONCompilationDatabase.cpp
@@ -206,11 +206,7 @@ JSONCompilationDatabase::getAllFiles() const {
 std::vector<CompileCommand>
 JSONCompilationDatabase::getAllCompileCommands() const {
   std::vector<CompileCommand> Commands;
-  for (llvm::StringMap< std::vector<CompileCommandRef> >::const_iterator
-        CommandsRefI = IndexByFile.begin(), CommandsRefEnd = IndexByFile.end();
-      CommandsRefI != CommandsRefEnd; ++CommandsRefI) {
-    getCommands(CommandsRefI->getValue(), Commands);
-  }
+  getCommands(AllCommands, Commands);
   return Commands;
 }
 
@@ -337,8 +333,9 @@ bool JSONCompilationDatabase::parse(std::string &ErrorMessage) {
     } else {
       llvm::sys::path::native(FileName, NativeFilePath);
     }
-    IndexByFile[NativeFilePath].push_back(
-        CompileCommandRef(Directory, File, *Command));
+    auto Cmd = CompileCommandRef(Directory, File, *Command);
+    IndexByFile[NativeFilePath].push_back(Cmd);
+    AllCommands.push_back(Cmd);
     MatchTrie.insert(NativeFilePath);
   }
   return true;
diff --git a/clang/unittests/Tooling/CompilationDatabaseTest.cpp b/clang/unittests/Tooling/CompilationDatabaseTest.cpp
index b7e7a72..380d86f 100644
--- a/clang/unittests/Tooling/CompilationDatabaseTest.cpp
+++ b/clang/unittests/Tooling/CompilationDatabaseTest.cpp
@@ -118,6 +118,25 @@ TEST(JSONCompilationDatabase, GetAllCompileCommands) {
   EXPECT_EQ(FileName2, Commands[1].Filename) << ErrorMessage;
   ASSERT_EQ(1u, Commands[1].CommandLine.size());
   EXPECT_EQ(Command2, Commands[1].CommandLine[0]) << ErrorMessage;
+
+  // Check that order is preserved.
+  Commands = getAllCompileCommands(
+      ("[{\"directory\":\"" + Directory2 + "\"," +
+             "\"command\":\"" + Command2 + "\","
+             "\"file\":\"" + FileName2 + "\"},"
+       " {\"directory\":\"" + Directory1 + "\"," +
+             "\"command\":\"" + Command1 + "\","
+             "\"file\":\"" + FileName1 + "\"}]").str(),
+      ErrorMessage);
+  EXPECT_EQ(2U, Commands.size()) << ErrorMessage;
+  EXPECT_EQ(Directory2, Commands[0].Directory) << ErrorMessage;
+  EXPECT_EQ(FileName2, Commands[0].Filename) << ErrorMessage;
+  ASSERT_EQ(1u, Commands[0].CommandLine.size());
+  EXPECT_EQ(Command2, Commands[0].CommandLine[0]) << ErrorMessage;
+  EXPECT_EQ(Directory1, Commands[1].Directory) << ErrorMessage;
+  EXPECT_EQ(FileName1, Commands[1].Filename) << ErrorMessage;
+  ASSERT_EQ(1u, Commands[1].CommandLine.size());
+  EXPECT_EQ(Command1, Commands[1].CommandLine[0]) << ErrorMessage;
 }
 
 static CompileCommand findCompileArgsInJsonDatabase(StringRef FileName,