rewrite_to_chrome_style: associate replacements with the affected file

tools/clang/rewrite_to_chrome_style/RewriteToChromeStyle.cpp

Index: tools/clang/rewrite_to_chrome_style/RewriteToChromeStyle.cpp
diff --git a/tools/clang/rewrite_to_chrome_style/RewriteToChromeStyle.cpp b/tools/clang/rewrite_to_chrome_style/RewriteToChromeStyle.cpp
index 3e18a280c40e9085490378d33d6ecff3d39bc06c..3374ea29ea6bd6ab8c3f0b796c90c6e5683384c2 100644
--- a/tools/clang/rewrite_to_chrome_style/RewriteToChromeStyle.cpp
+++ b/tools/clang/rewrite_to_chrome_style/RewriteToChromeStyle.cpp
@@ -14,10 +14,9 @@
 
 #include <assert.h>
 #include <algorithm>
-#include <fstream>
 #include <memory>
+#include <set>
 #include <string>
-#include <unordered_map>
 
 #include "clang/AST/ASTContext.h"
 #include "clang/ASTMatchers/ASTMatchFinder.h"
@@ -33,12 +32,7 @@
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/TargetSelect.h"
 
-#if defined(_WIN32)
-#include <windows.h>
-#else
-#include <sys/file.h>
-#include <unistd.h>
-#endif
+#include "EditTracker.h"
 
 using namespace clang::ast_matchers;
 using clang::tooling::CommonOptionsParser;
@@ -694,19 +688,17 @@ class RewriterBase : public MatchFinder::MatchCallback {
 
     clang::SourceLocation loc =
         TargetNodeTraits<TargetNode>::GetLoc(GetTargetNode(result));
+    edit_tracker_.Add(*result.SourceManager, loc, old_name, new_name);

[Łukasz Anforowicz, 2016/12/22 17:34:36]

We might have to be careful when merging the change above with the changes for
handling to##macroArg.  The merge should be straightforward, but we might want
to double check that the edit_tracker_.Add call:
1. Uses |old_name| and |new_name| (rather than the |expected_old_text| and
|new_text|)
2. And I think using any |loc| ("original loc" VS "jumped out of scratch space
loc") is okay here.  Although maybe "original loc" is better...

[dcheng, 2016/12/22 20:49:40]

Yeah I'm not sure what the best approach is. I think we want the original loc,
in case we do any processing though?

+
     clang::CharSourceRange range = clang::CharSourceRange::getTokenRange(loc);
     replacements_->emplace(*result.SourceManager, range, new_name);
-    replacement_names_.emplace(old_name.str(), std::move(new_name));
   }
 
-  const std::unordered_map<std::string, std::string>& replacement_names()
-      const {
-    return replacement_names_;
-  }
+  const EditTracker& edit_tracker() const { return edit_tracker_; }
 
  private:
   std::set<Replacement>* const replacements_;
-  std::unordered_map<std::string, std::string> replacement_names_;
+  EditTracker edit_tracker_;
 };
 
 template <typename DeclNode, typename TargetNode>
@@ -1287,38 +1279,15 @@ int main(int argc, const char* argv[]) {
   if (result != 0)
     return result;
 
-#if defined(_WIN32)
-  HANDLE lockfd = CreateFile("rewrite-sym.lock", GENERIC_READ, FILE_SHARE_READ,
-                             NULL, OPEN_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL);
-  OVERLAPPED overlapped = {};
-  LockFileEx(lockfd, LOCKFILE_EXCLUSIVE_LOCK, 0, 1, 0, &overlapped);
-#else
-  int lockfd = open("rewrite-sym.lock", O_RDWR | O_CREAT, 0666);
-  while (flock(lockfd, LOCK_EX)) {  // :D
-  }
-#endif
-
-  std::ofstream replacement_db_file("rewrite-sym.txt",
-                                    std::ios_base::out | std::ios_base::app);
-  for (const auto& p : field_decl_rewriter.replacement_names())
-    replacement_db_file << "var:" << p.first << ":" << p.second << "\n";
-  for (const auto& p : var_decl_rewriter.replacement_names())
-    replacement_db_file << "var:" << p.first << ":" << p.second << "\n";
-  for (const auto& p : enum_member_decl_rewriter.replacement_names())
-    replacement_db_file << "enu:" << p.first << ":" << p.second << "\n";
-  for (const auto& p : function_decl_rewriter.replacement_names())
-    replacement_db_file << "fun:" << p.first << ":" << p.second << "\n";
-  for (const auto& p : method_decl_rewriter.replacement_names())
-    replacement_db_file << "fun:" << p.first << ":" << p.second << "\n";
-  replacement_db_file.close();
-
-#if defined(_WIN32)
-  UnlockFileEx(lockfd, 0, 1, 0, &overlapped);
-  CloseHandle(lockfd);
-#else
-  flock(lockfd, LOCK_UN);
-  close(lockfd);

[Łukasz Anforowicz, 2016/12/22 17:34:36]

I very much agree with the decision to just emit everything to stdout - this
will play well with run_tool.py

-#endif
+  // Supplemental data for the Blink rename rebase helper.
+  // TODO(dcheng): There's a lot of match rewriters missing from this list.

[dcheng, 2016/12/22 10:26:22]

We'll add these in a followup.

One tricky bit: it's not clear how we're going to disambiguate some of these
(e.g. the matchers for using declarations). Perhaps the rebase helper should
just look at the type of naming change to guess the original variable type?

[Łukasz Anforowicz, 2016/12/22 17:34:36]

1. I don't understand how the rebase helper will use the "prefix" / "tag" - will
it behave differently for "fun" vs "var"?

2. Maybe just use "other" or "unknown" for the unresolved matchers?

[dcheng, 2016/12/22 20:49:40]

I think I'll tweak this to infer based on the type of rename.
It's useful because you can have 

int mainFunction() {
  int mainFunction = 0;
}

And we'll rename those differently.

+  llvm::outs() << "==== BEGIN TRACKED EDITS ====\n";
+  field_decl_rewriter.edit_tracker().SerializeTo("var", llvm::outs());
+  var_decl_rewriter.edit_tracker().SerializeTo("var", llvm::outs());
+  enum_member_decl_rewriter.edit_tracker().SerializeTo("enu", llvm::outs());
+  function_decl_rewriter.edit_tracker().SerializeTo("fun", llvm::outs());
+  method_decl_rewriter.edit_tracker().SerializeTo("fun", llvm::outs());
+  llvm::outs() << "==== END TRACKED EDITS ====\n";

[dcheng, 2016/12/22 10:26:22]

We're going to split run_tool.py in half: one half will run the tool and collect
all the outputs. The other half of the tool will apply the edits from the
scraping the collected output.

Similarly, we'll build the rebase helper DB by scraping the output.

[Łukasz Anforowicz, 2016/12/22 17:34:36]

Acknowledged.

 
   // Serialization format is documented in tools/clang/scripts/run_tool.py
   llvm::outs() << "==== BEGIN EDITS ====\n";