Split library clangRewrite into clangRewriteCore and clangRewriteFrontend.

This is similar to how we divide up the StaticAnalyzer libraries to separate
core functionality to what is clearly associated with Frontend actions.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@163050 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 205 insertions, 0 deletions

diff --git a/lib/Rewrite/Frontend/FixItRewriter.cpp b/lib/Rewrite/Frontend/FixItRewriter.cpp
new file mode 100644
index 0000000000..43a1ab1ac1
--- /dev/null
+++ b/lib/Rewrite/Frontend/FixItRewriter.cpp
@@ -0,0 +1,205 @@
+//===--- FixItRewriter.cpp - Fix-It Rewriter Diagnostic Client --*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This is a diagnostic client adaptor that performs rewrites as
+// suggested by code modification hints attached to diagnostics. It
+// then forwards any diagnostics to the adapted diagnostic client.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Rewrite/Frontend/FixItRewriter.h"
+#include "clang/Edit/Commit.h"
+#include "clang/Edit/EditsReceiver.h"
+#include "clang/Basic/FileManager.h"
+#include "clang/Basic/SourceLocation.h"
+#include "clang/Basic/SourceManager.h"
+#include "clang/Frontend/FrontendDiagnostic.h"
+#include "llvm/Support/raw_ostream.h"
+#include "llvm/Support/Path.h"
+#include "llvm/ADT/OwningPtr.h"
+#include <cstdio>
+
+using namespace clang;
+
+FixItRewriter::FixItRewriter(DiagnosticsEngine &Diags, SourceManager &SourceMgr,
+                             const LangOptions &LangOpts,
+                             FixItOptions *FixItOpts)
+  : Diags(Diags),
+    Editor(SourceMgr, LangOpts),
+    Rewrite(SourceMgr, LangOpts),
+    FixItOpts(FixItOpts),
+    NumFailures(0),
+    PrevDiagSilenced(false) {
+  OwnsClient = Diags.ownsClient();
+  Client = Diags.takeClient();
+  Diags.setClient(this);
+}
+
+FixItRewriter::~FixItRewriter() {
+  Diags.takeClient();
+  Diags.setClient(Client, OwnsClient);
+}
+
+bool FixItRewriter::WriteFixedFile(FileID ID, raw_ostream &OS) {
+  const RewriteBuffer *RewriteBuf = Rewrite.getRewriteBufferFor(ID);
+  if (!RewriteBuf) return true;
+  RewriteBuf->write(OS);
+  OS.flush();
+  return false;
+}
+
+namespace {
+
+class RewritesReceiver : public edit::EditsReceiver {
+  Rewriter &Rewrite;
+
+public:
+  RewritesReceiver(Rewriter &Rewrite) : Rewrite(Rewrite) { }
+
+  virtual void insert(SourceLocation loc, StringRef text) {
+    Rewrite.InsertText(loc, text);
+  }
+  virtual void replace(CharSourceRange range, StringRef text) {
+    Rewrite.ReplaceText(range.getBegin(), Rewrite.getRangeSize(range), text);
+  }
+};
+
+}
+
+bool FixItRewriter::WriteFixedFiles(
+            std::vector<std::pair<std::string, std::string> > *RewrittenFiles) {
+  if (NumFailures > 0 && !FixItOpts->FixWhatYouCan) {
+    Diag(FullSourceLoc(), diag::warn_fixit_no_changes);
+    return true;
+  }
+
+  RewritesReceiver Rec(Rewrite);
+  Editor.applyRewrites(Rec);
+
+  for (iterator I = buffer_begin(), E = buffer_end(); I != E; ++I) {
+    const FileEntry *Entry = Rewrite.getSourceMgr().getFileEntryForID(I->first);
+    int fd;
+    std::string Filename = FixItOpts->RewriteFilename(Entry->getName(), fd);
+    std::string Err;
+    OwningPtr<llvm::raw_fd_ostream> OS;
+    if (fd != -1) {
+      OS.reset(new llvm::raw_fd_ostream(fd, /*shouldClose=*/true));
+    } else {
+      OS.reset(new llvm::raw_fd_ostream(Filename.c_str(), Err,
+                                        llvm::raw_fd_ostream::F_Binary));
+    }
+    if (!Err.empty()) {
+      Diags.Report(clang::diag::err_fe_unable_to_open_output)
+          << Filename << Err;
+      continue;
+    }
+    RewriteBuffer &RewriteBuf = I->second;
+    RewriteBuf.write(*OS);
+    OS->flush();
+
+    if (RewrittenFiles)
+      RewrittenFiles->push_back(std::make_pair(Entry->getName(), Filename));
+  }
+
+  return false;
+}
+
+bool FixItRewriter::IncludeInDiagnosticCounts() const {
+  return Client ? Client->IncludeInDiagnosticCounts() : true;
+}
+
+void FixItRewriter::HandleDiagnostic(DiagnosticsEngine::Level DiagLevel,
+                                     const Diagnostic &Info) {
+  // Default implementation (Warnings/errors count).
+  DiagnosticConsumer::HandleDiagnostic(DiagLevel, Info);
+
+  if (!FixItOpts->Silent ||
+      DiagLevel >= DiagnosticsEngine::Error ||
+      (DiagLevel == DiagnosticsEngine::Note && !PrevDiagSilenced) ||
+      (DiagLevel > DiagnosticsEngine::Note && Info.getNumFixItHints())) {
+    Client->HandleDiagnostic(DiagLevel, Info);
+    PrevDiagSilenced = false;
+  } else {
+    PrevDiagSilenced = true;
+  }
+
+  // Skip over any diagnostics that are ignored or notes.
+  if (DiagLevel <= DiagnosticsEngine::Note)
+    return;
+  // Skip over errors if we are only fixing warnings.
+  if (DiagLevel >= DiagnosticsEngine::Error && FixItOpts->FixOnlyWarnings) {
+    ++NumFailures;
+    return;
+  }
+
+  // Make sure that we can perform all of the modifications we
+  // in this diagnostic.
+  edit::Commit commit(Editor);
+  for (unsigned Idx = 0, Last = Info.getNumFixItHints();
+       Idx < Last; ++Idx) {
+    const FixItHint &Hint = Info.getFixItHint(Idx);
+
+    if (Hint.CodeToInsert.empty()) {
+      if (Hint.InsertFromRange.isValid())
+        commit.insertFromRange(Hint.RemoveRange.getBegin(),
+                           Hint.InsertFromRange, /*afterToken=*/false,
+                           Hint.BeforePreviousInsertions);
+      else
+        commit.remove(Hint.RemoveRange);
+    } else {
+      if (Hint.RemoveRange.isTokenRange() ||
+          Hint.RemoveRange.getBegin() != Hint.RemoveRange.getEnd())
+        commit.replace(Hint.RemoveRange, Hint.CodeToInsert);
+      else
+        commit.insert(Hint.RemoveRange.getBegin(), Hint.CodeToInsert,
+                    /*afterToken=*/false, Hint.BeforePreviousInsertions);
+    }
+  }
+  bool CanRewrite = Info.getNumFixItHints() > 0 && commit.isCommitable();
+
+  if (!CanRewrite) {
+    if (Info.getNumFixItHints() > 0)
+      Diag(Info.getLocation(), diag::note_fixit_in_macro);
+
+    // If this was an error, refuse to perform any rewriting.
+    if (DiagLevel >= DiagnosticsEngine::Error) {
+      if (++NumFailures == 1)
+        Diag(Info.getLocation(), diag::note_fixit_unfixed_error);
+    }
+    return;
+  }
+  
+  if (!Editor.commit(commit)) {
+    ++NumFailures;
+    Diag(Info.getLocation(), diag::note_fixit_failed);
+    return;
+  }
+
+  Diag(Info.getLocation(), diag::note_fixit_applied);
+}
+
+/// \brief Emit a diagnostic via the adapted diagnostic client.
+void FixItRewriter::Diag(SourceLocation Loc, unsigned DiagID) {
+  // When producing this diagnostic, we temporarily bypass ourselves,
+  // clear out any current diagnostic, and let the downstream client
+  // format the diagnostic.
+  Diags.takeClient();
+  Diags.setClient(Client);
+  Diags.Clear();
+  Diags.Report(Loc, DiagID);
+  Diags.takeClient();
+  Diags.setClient(this);
+}
+
+DiagnosticConsumer *FixItRewriter::clone(DiagnosticsEngine &Diags) const {
+  return new FixItRewriter(Diags, Diags.getSourceManager(), 
+                           Rewrite.getLangOpts(), FixItOpts);
+}
+
+FixItOptions::~FixItOptions() {}