/// \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 Columns,
const SourceColumnMap &map) {
unsigned MaxColumns = std::max<unsigned>(map.columns(),
std::max(CaretLine.size(),
FixItInsertionLine.size()));
// if the number of columns is less than the desired number we're done
if (MaxColumns <= Columns)
return;
// no special characters allowed in CaretLine or FixItInsertionLine
assert(CaretLine.end() ==
std::find_if(CaretLine.begin(), CaretLine.end(),
char_out_of_range(' ','~')));
assert(FixItInsertionLine.end() ==
std::find_if(FixItInsertionLine.begin(), FixItInsertionLine.end(),
char_out_of_range(' ','~')));
// 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(static_cast<unsigned char>(CaretLine[CaretStart])))
break;
for (; CaretEnd != CaretStart; --CaretEnd)
if (!isspace(static_cast<unsigned char>(CaretLine[CaretEnd - 1])))
break;
// caret has already been inserted into CaretLine so the above whitespace
// check is guaranteed to include the caret
// 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(static_cast<unsigned char>(FixItInsertionLine[FixItStart])))
break;
for (; FixItEnd != FixItStart; --FixItEnd)
if (!isspace(static_cast<unsigned char>(FixItInsertionLine[FixItEnd - 1])))
break;
CaretStart = std::min(FixItStart, CaretStart);
CaretEnd = std::max(FixItEnd, CaretEnd);
}
// CaretEnd may have been set at the middle of a character
// If it's not at a character's first column then advance it past the current
// character.
while (static_cast<int>(CaretEnd) < map.columns() &&
-1 == map.columnToByte(CaretEnd))
++CaretEnd;
assert((static_cast<int>(CaretStart) > map.columns() ||
-1!=map.columnToByte(CaretStart)) &&
"CaretStart must not point to a column in the middle of a source"
" line character");
assert((static_cast<int>(CaretEnd) > map.columns() ||
-1!=map.columnToByte(CaretEnd)) &&
"CaretEnd must not point to a column in the middle of a source line"
" character");
// 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.
unsigned SourceStart = map.columnToByte(std::min<unsigned>(CaretStart,
map.columns()));
unsigned SourceEnd = map.columnToByte(std::min<unsigned>(CaretEnd,
map.columns()));
unsigned CaretColumnsOutsideSource = CaretEnd-CaretStart
- (map.byteToColumn(SourceEnd)-map.byteToColumn(SourceStart));
char const *front_ellipse = " ...";
char const *front_space = " ";
char const *back_ellipse = "...";
unsigned ellipses_space = strlen(front_ellipse) + strlen(back_ellipse);
unsigned TargetColumns = Columns;
// Give us extra room for the ellipses
// and any of the caret line that extends past the source
if (TargetColumns > ellipses_space+CaretColumnsOutsideSource)
TargetColumns -= ellipses_space+CaretColumnsOutsideSource;
while (SourceStart>0 || SourceEnd<SourceLine.size()) {
bool ExpandedRegion = false;
if (SourceStart>0) {
unsigned NewStart = map.startOfPreviousColumn(SourceStart);
// Skip over any whitespace we see here; we're looking for
// another bit of interesting text.
// FIXME: Detect non-ASCII whitespace characters too.
while (NewStart &&
isspace(static_cast<unsigned char>(SourceLine[NewStart])))
NewStart = map.startOfPreviousColumn(NewStart);
// Skip over this bit of "interesting" text.
while (NewStart) {
unsigned Prev = map.startOfPreviousColumn(NewStart);
if (isspace(static_cast<unsigned char>(SourceLine[Prev])))
break;
NewStart = Prev;
}
assert(map.byteToColumn(NewStart) != -1);
unsigned NewColumns = map.byteToColumn(SourceEnd) -
map.byteToColumn(NewStart);
if (NewColumns <= TargetColumns) {
SourceStart = NewStart;
ExpandedRegion = true;
}
}
if (SourceEnd<SourceLine.size()) {
unsigned NewEnd = map.startOfNextColumn(SourceEnd);
// Skip over any whitespace we see here; we're looking for
// another bit of interesting text.
// FIXME: Detect non-ASCII whitespace characters too.
while (NewEnd < SourceLine.size() &&
isspace(static_cast<unsigned char>(SourceLine[NewEnd])))
NewEnd = map.startOfNextColumn(NewEnd);
// Skip over this bit of "interesting" text.
while (NewEnd < SourceLine.size() &&
!isspace(static_cast<unsigned char>(SourceLine[NewEnd])))
NewEnd = map.startOfNextColumn(NewEnd);
assert(map.byteToColumn(NewEnd) != -1);
unsigned NewColumns = map.byteToColumn(NewEnd) -
map.byteToColumn(SourceStart);
if (NewColumns <= TargetColumns) {
SourceEnd = NewEnd;
ExpandedRegion = true;
}
}
if (!ExpandedRegion)
break;
}
CaretStart = map.byteToColumn(SourceStart);
CaretEnd = map.byteToColumn(SourceEnd) + CaretColumnsOutsideSource;
// [CaretStart, CaretEnd) is the slice we want. Update the various
// output lines to show only this slice, with two-space padding
// before the lines so that it looks nicer.
assert(CaretStart!=(unsigned)-1 && CaretEnd!=(unsigned)-1 &&
SourceStart!=(unsigned)-1 && SourceEnd!=(unsigned)-1);
assert(SourceStart <= SourceEnd);
assert(CaretStart <= CaretEnd);
unsigned BackColumnsRemoved
= map.byteToColumn(SourceLine.size())-map.byteToColumn(SourceEnd);
unsigned FrontColumnsRemoved = CaretStart;
unsigned ColumnsKept = CaretEnd-CaretStart;
// We checked up front that the line needed truncation
assert(FrontColumnsRemoved+ColumnsKept+BackColumnsRemoved > Columns);
// The line needs some trunctiona, and we'd prefer to keep the front
// if possible, so remove the back
if (BackColumnsRemoved > strlen(back_ellipse))
SourceLine.replace(SourceEnd, std::string::npos, back_ellipse);
// If that's enough then we're done
if (FrontColumnsRemoved+ColumnsKept <= Columns)
return;
// Otherwise remove the front as well
if (FrontColumnsRemoved > strlen(front_ellipse)) {
SourceLine.replace(0, SourceStart, front_ellipse);
CaretLine.replace(0, CaretStart, front_space);
if (!FixItInsertionLine.empty())
FixItInsertionLine.replace(0, CaretStart, front_space);
}
}
/// \brief Emit a code snippet and caret line.
///
/// This routine emits a single line's code snippet and caret line..
///
/// \param Loc The location for the caret.
/// \param Ranges The underlined ranges for this code snippet.
/// \param Hints The FixIt hints active for this diagnostic.
void TextDiagnostic::emitSnippetAndCaret(
SourceLocation Loc, DiagnosticsEngine::Level Level,
SmallVectorImpl<CharSourceRange>& Ranges,
ArrayRef<FixItHint> Hints,
const SourceManager &SM) {
assert(Loc.isValid() && "must have a valid source location here");
assert(Loc.isFileID() && "must have a file location here");
// If caret diagnostics are enabled and we have location, we want to
// emit the caret. However, we only do this if the location moved
// from the last diagnostic, if the last diagnostic was a note that
// was part of a different warning or error diagnostic, or if the
// diagnostic has ranges. We don't want to emit the same caret
// multiple times if one loc has multiple diagnostics.
if (!DiagOpts->ShowCarets)
return;
if (Loc == LastLoc && Ranges.empty() && Hints.empty() &&
(LastLevel != DiagnosticsEngine::Note || Level == LastLevel))
return;
// Decompose the location into a FID/Offset pair.
std::pair<FileID, unsigned> LocInfo = SM.getDecomposedLoc(Loc);
FileID FID = LocInfo.first;
unsigned FileOffset = LocInfo.second;
// Get information about the buffer it points into.
bool Invalid = false;
StringRef BufData = SM.getBufferData(FID, &Invalid);
if (Invalid)
return;
const char *BufStart = BufData.data();
const char *BufEnd = BufStart + BufData.size();
unsigned LineNo = SM.getLineNumber(FID, FileOffset);
unsigned ColNo = SM.getColumnNumber(FID, FileOffset);
// Arbitrarily stop showing snippets when the line is too long.
static const size_t MaxLineLengthToPrint = 4096;
if (ColNo > MaxLineLengthToPrint)
return;
// Rewind from the current position to the start of the line.
const char *TokPtr = BufStart+FileOffset;
const char *LineStart = TokPtr-ColNo+1; // Column # is 1-based.
// Compute the line end. Scan forward from the error position to the end of
// the line.
const char *LineEnd = TokPtr;
while (*LineEnd != '\n' && *LineEnd != '\r' && LineEnd != BufEnd)
++LineEnd;
// Arbitrarily stop showing snippets when the line is too long.
if (size_t(LineEnd - LineStart) > MaxLineLengthToPrint)
return;
// Trim trailing null-bytes.
StringRef Line(LineStart, LineEnd - LineStart);
while (Line.size() > ColNo && Line.back() == '\0')
Line = Line.drop_back();
// Copy the line of code into an std::string for ease of manipulation.
std::string SourceLine(Line.begin(), Line.end());
// Build the byte to column map.
const SourceColumnMap sourceColMap(SourceLine, DiagOpts->TabStop);
// Create a line for the caret that is filled with spaces that is the same
// number of columns as the line of source code.
std::string CaretLine(sourceColMap.columns(), ' ');
// Highlight all of the characters covered by Ranges with ~ characters.
for (SmallVectorImpl<CharSourceRange>::iterator I = Ranges.begin(),
E = Ranges.end();
I != E; ++I)
highlightRange(*I, LineNo, FID, sourceColMap, CaretLine, SM, LangOpts);
// Next, insert the caret itself.
ColNo = sourceColMap.byteToContainingColumn(ColNo-1);
if (CaretLine.size()<ColNo+1)
CaretLine.resize(ColNo+1, ' ');
CaretLine[ColNo] = '^';
std::string FixItInsertionLine = buildFixItInsertionLine(LineNo,
sourceColMap,
Hints, SM,
DiagOpts.get());
// If the source line is too long for our terminal, select only the
// "interesting" source region within that line.
unsigned Columns = DiagOpts->MessageLength;
if (Columns)
selectInterestingSourceRegion(SourceLine, CaretLine, FixItInsertionLine,
Columns, sourceColMap);
// If we are in -fdiagnostics-print-source-range-info mode, we are trying
// to produce easily machine parsable output. Add a space before the
// source line and the caret to make it trivial to tell the main diagnostic
// line from what the user is intended to see.
if (DiagOpts->ShowSourceRanges) {
SourceLine = ' ' + SourceLine;
CaretLine = ' ' + CaretLine;
}
// Finally, remove any blank spaces from the end of CaretLine.
while (CaretLine[CaretLine.size()-1] == ' ')
CaretLine.erase(CaretLine.end()-1);
// Emit what we have computed.
emitSnippet(SourceLine);
if (DiagOpts->ShowColors)
OS.changeColor(caretColor, true);
OS << CaretLine << '\n';
if (DiagOpts->ShowColors)
OS.resetColor();
if (!FixItInsertionLine.empty()) {
if (DiagOpts->ShowColors)
// Print fixit line in color
OS.changeColor(fixitColor, false);
if (DiagOpts->ShowSourceRanges)
OS << ' ';
OS << FixItInsertionLine << '\n';
if (DiagOpts->ShowColors)
OS.resetColor();
}
// Print out any parseable fixit information requested by the options.
emitParseableFixits(Hints, SM);
}
