path: root/lib/Frontend/TextDiagnostic.cpp

//===--- TextDiagnostic.cpp - Text Diagnostic Pretty-Printing -------------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//

#include "clang/Frontend/TextDiagnostic.h"
#include "clang/Basic/FileManager.h"
#include "clang/Basic/SourceManager.h"
#include "clang/Frontend/DiagnosticOptions.h"
#include "clang/Lex/Lexer.h"
#include "llvm/Support/MemoryBuffer.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/ADT/SmallString.h"
#include <algorithm>
using namespace clang;

static const enum raw_ostream::Colors noteColor =
  raw_ostream::BLACK;
static const enum raw_ostream::Colors fixitColor =
  raw_ostream::GREEN;
static const enum raw_ostream::Colors caretColor =
  raw_ostream::GREEN;
static const enum raw_ostream::Colors warningColor =
  raw_ostream::MAGENTA;
static const enum raw_ostream::Colors errorColor = raw_ostream::RED;
static const enum raw_ostream::Colors fatalColor = raw_ostream::RED;
// Used for changing only the bold attribute.
static const enum raw_ostream::Colors savedColor =
  raw_ostream::SAVEDCOLOR;

/// \brief Number of spaces to indent when word-wrapping.
const unsigned WordWrapIndentation = 6;

/// \brief When the source code line we want to print is too long for
/// the terminal, select the "interesting" region.
static void selectInterestingSourceRegion(std::string &SourceLine,
                                          std::string &CaretLine,
                                          std::string &FixItInsertionLine,
                                          unsigned EndOfCaretToken,
                                          unsigned Columns) {
  unsigned MaxSize = std::max(SourceLine.size(),
                              std::max(CaretLine.size(), 
                                       FixItInsertionLine.size()));
  if (MaxSize > SourceLine.size())
    SourceLine.resize(MaxSize, ' ');
  if (MaxSize > CaretLine.size())
    CaretLine.resize(MaxSize, ' ');
  if (!FixItInsertionLine.empty() && MaxSize > FixItInsertionLine.size())
    FixItInsertionLine.resize(MaxSize, ' ');
    
  // Find the slice that we need to display the full caret line
  // correctly.
  unsigned CaretStart = 0, CaretEnd = CaretLine.size();
  for (; CaretStart != CaretEnd; ++CaretStart)
    if (!isspace(CaretLine[CaretStart]))
      break;

  for (; CaretEnd != CaretStart; --CaretEnd)
    if (!isspace(CaretLine[CaretEnd - 1]))
      break;

  // Make sure we don't chop the string shorter than the caret token
  // itself.
  if (CaretEnd < EndOfCaretToken)
    CaretEnd = EndOfCaretToken;

  // If we have a fix-it line, make sure the slice includes all of the
  // fix-it information.
  if (!FixItInsertionLine.empty()) {
    unsigned FixItStart = 0, FixItEnd = FixItInsertionLine.size();
    for (; FixItStart != FixItEnd; ++FixItStart)
      if (!isspace(FixItInsertionLine[FixItStart]))
        break;

    for (; FixItEnd != FixItStart; --FixItEnd)
      if (!isspace(FixItInsertionLine[FixItEnd - 1]))
        break;

    if (FixItStart < CaretStart)
      CaretStart = FixItStart;
    if (FixItEnd > CaretEnd)
      CaretEnd = FixItEnd;
  }

  // CaretLine[CaretStart, CaretEnd) contains all of the interesting
  // parts of the caret line. While this slice is smaller than the
  // number of columns we have, try to grow the slice to encompass
  // more context.

  // If the end of the interesting region comes before we run out of
  // space in the terminal, start at the beginning of the line.
  if (Columns > 3 && CaretEnd < Columns - 3)
    CaretStart = 0;

  unsigned TargetColumns = Columns;
  if (TargetColumns > 8)
    TargetColumns -= 8; // Give us extra room for the ellipses.