Added Fixer implementation and fix() interface in clang-format for removing redundant code.

Summary:
After applying replacements, redundant code like extra commas or empty namespaces
might be introduced. Fixer can detect and remove any redundant code introduced by replacements.
The current implementation only handles redundant commas.

Reviewers: djasper, klimek

Subscribers: ioeric, mprobst, klimek, cfe-commits

Differential Revision: http://reviews.llvm.org/D18551

llvm-svn: 267416

1 files changed, 66 insertions, 0 deletions

diff --git a/clang/lib/Format/AffectedRangeManager.h b/clang/lib/Format/AffectedRangeManager.h
new file mode 100644
index 00000000000..9142315a9f3
--- /dev/null
+++ b/clang/lib/Format/AffectedRangeManager.h
@@ -0,0 +1,66 @@
+//===--- AffectedRangeManager.h - Format C++ code ---------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// \brief AffectedRangeManager class manages affected ranges in the code.
+///
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_LIB_FORMAT_AFFECTEDRANGEMANAGER_H
+#define LLVM_CLANG_LIB_FORMAT_AFFECTEDRANGEMANAGER_H
+
+#include "clang/Basic/SourceManager.h"
+
+namespace clang {
+namespace format {
+
+struct FormatToken;
+class AnnotatedLine;
+
+class AffectedRangeManager {
+public:
+  AffectedRangeManager(SourceManager &SourceMgr,
+                       const ArrayRef<CharSourceRange> Ranges)
+      : SourceMgr(SourceMgr), Ranges(Ranges.begin(), Ranges.end()) {}
+
+  // Determines which lines are affected by the SourceRanges given as input.
+  // Returns \c true if at least one line between I and E or one of their
+  // children is affected.
+  bool computeAffectedLines(SmallVectorImpl<AnnotatedLine *>::iterator I,
+                            SmallVectorImpl<AnnotatedLine *>::iterator E);
+
+  // Returns true if 'Range' intersects with one of the input ranges.
+  bool affectsCharSourceRange(const CharSourceRange &Range);
+
+private:
+  // Returns true if the range from 'First' to 'Last' intersects with one of the
+  // input ranges.
+  bool affectsTokenRange(const FormatToken &First, const FormatToken &Last,
+                         bool IncludeLeadingNewlines);
+
+  // Returns true if one of the input ranges intersect the leading empty lines
+  // before 'Tok'.
+  bool affectsLeadingEmptyLines(const FormatToken &Tok);
+
+  // Marks all lines between I and E as well as all their children as affected.
+  void markAllAsAffected(SmallVectorImpl<AnnotatedLine *>::iterator I,
+                         SmallVectorImpl<AnnotatedLine *>::iterator E);
+
+  // Determines whether 'Line' is affected by the SourceRanges given as input.
+  // Returns \c true if line or one if its children is affected.
+  bool nonPPLineAffected(AnnotatedLine *Line,
+                         const AnnotatedLine *PreviousLine);
+  SourceManager &SourceMgr;
+  const SmallVector<CharSourceRange, 8> Ranges;
+};
+
+} // namespace format
+} // namespace clang
+
+#endif // LLVM_CLANG_LIB_FORMAT_WHITESPACEMANAGER_H