scanBlockScalar now reads to a slice... and is a lot more complicated.

This commit is contained in:
Ferdinand Majerech 2014-07-26 02:33:16 +02:00
parent 7bbd5ab5b3
commit fb93ad7cf1

View file

@ -1183,6 +1183,12 @@ final class Scanner
uint indent = max(1, indent_ + 1);
reader_.sliceBuilder.begin();
alias Transaction = SliceBuilder.Transaction;
// Used to strip the last line breaks written to the slice at the end of the
// scalar, which may be needed based on chomping.
Transaction breaksTransaction = Transaction(reader_.sliceBuilder);
// Read the first indentation/line breaks before the scalar.
size_t startLen = reader_.sliceBuilder.length;
if(increment == int.min)
{
auto indentation = scanBlockScalarIndentationToSlice();
@ -1194,25 +1200,32 @@ final class Scanner
indent += increment - 1;
endMark = scanBlockScalarBreaksToSlice(indent);
}
dstring breaks = reader_.sliceBuilder.finish();
size_t endLen = reader_.sliceBuilder.length;
dchar[] lineBreak = ""d.dup;
//Using appender_, so clear it when we're done.
scope(exit){appender_.clear();}
// Scan the inner part of the block scalar.
while(reader_.column == indent && reader_.peek() != '\0')
{
appender_.put(breaks);
breaksTransaction.commit();
const bool leadingNonSpace = !" \t"d.canFind(reader_.peek());
appender_.put(scanToNextBreak());
// This is where the 'interesting' non-whitespace data gets read.
scanToNextBreakToSlice();
lineBreak = [scanLineBreak()];
auto scalarBreaks = scanBlockScalarBreaks(indent);
breaks = scalarBreaks[0];
endMark = scalarBreaks[1];
// This transaction serves to rollback data read in the
// scanBlockScalarBreaksToSlice() call.
breaksTransaction = Transaction(reader_.sliceBuilder);
startLen = reader_.sliceBuilder.length;
// The line breaks should actually be written _after_ the if() block
// below. We work around that by inserting
endMark = scanBlockScalarBreaksToSlice(indent);
endLen = reader_.sliceBuilder.length;
// This will not run during the last iteration (see the if() vs the
// while()), hence breaksTransaction rollback (which happens after this
// loop) will never roll back data written in this if() block.
if(reader_.column == indent && reader_.peek() != '\0')
{
//Unfortunately, folding rules are ambiguous.
@ -1221,9 +1234,20 @@ final class Scanner
if(style == ScalarStyle.Folded && lineBreak == "\n" &&
leadingNonSpace && !" \t"d.canFind(reader_.peek()))
{
if(breaks.length == 0){appender_.put(' ');}
// No breaks were scanned; no need to insert the space in the
// middle of slice.
if(startLen == endLen)
{
reader_.sliceBuilder.write(' ');
}
else{appender_.put(lineBreak);}
}
else
{
// We need to insert in the middle of the slice in case any line
// breaks were scanned.
reader_.sliceBuilder.insertBack(lineBreak[0], endLen - startLen);
}
////this is Clark Evans's interpretation (also in the spec
////examples):
//
@ -1237,12 +1261,38 @@ final class Scanner
//}
//else{appender_.put(lineBreak);}
}
else{break;}
else
{
break;
}
}
if(chomping != Chomping.Strip){appender_.put(lineBreak);}
if(chomping == Chomping.Keep){appender_.put(breaks);}
return scalarToken(startMark, endMark, utf32To8(appender_.data), style);
// If chompint is Keep, we keep (commit) the last scanned line breaks
// (which are at the end of the scalar). Otherwise re remove them (end the
// transaction).
if(chomping == Chomping.Keep) { breaksTransaction.commit(); }
else { breaksTransaction.__dtor(); }
if(chomping != Chomping.Strip && !lineBreak.empty)
{
// If chomping is Keep, we keep the line break but the first line break
// that isn't stripped (since chomping isn't Strip in this branch) must
// be inserted _before_ the other line breaks.
if(chomping == Chomping.Keep)
{
reader_.sliceBuilder.insertBack(lineBreak[0], endLen - startLen);
}
// If chomping is not Keep, breaksTransaction was cancelled so we can
// directly write the first line break (as it isn't stripped - chomping
// is not Strip)
else
{
reader_.sliceBuilder.write(lineBreak[0]);
}
}
const slice = reader_.sliceBuilder.finish();
return scalarToken(startMark, endMark, slice.utf32To8, style);
}
/// Scan chomping and indentation indicators of a scalar token.