Re: EOL control in scintilla

I tracked down the extra spaces problem. It turned out to be a space at  
the end of the line (after the EOL character(s)), not at the beginning,  
which is why it doesn't show up on the first line.

Here's the cause of the problem:
# How many characters are on a line, not including end of line characters?
sub LineLength {
  my ($self, $line) = @_;
  return $self->SendMessage (2350, $line, 0);
}

Scintilla's documentation says:
SCI_LINELENGTH(int line)
This returns the length of the line, including any line end characters. If  
line is negative or beyond the last line in the document, the result is 0.  
If you want the length of the line not including any end of line  
characters, use SCI_GETLINEENDPOSITION(line) - SCI_POSITIONFROMLINE(line).

Laurent's code makes an incorrect assumption about EOL markers and  
SCI_LINELENGTH. (Although it may have been correct when it was coded, and  
Scintilla later changed.) Everywhere Laurent has used LineLength to get  
the text at a line, he has done the following:
my $lenght = $self->LineLength($line);
my $text   = " " x ($lenght + 1);
$self->SendMessageNP (2153, $line, $text);

He has to create the buffer first, because SendMessage requires the memory  
to be already allocated, so he creates a buffer of spaces. But he creates  
it one byte too long, so there's a trailing space in the returned text.

(SendMessageNP is an alias for SendMessage with the second parameter as a  
pointer. There is also SendMessage PN for the first parameter as a pointer  
and SendMessagePP for both parameters as pointers. It would probably be  
better to have a single SendMessage function, and use references when you  
want a parameter to be a pointer, but I don't currently have a compiler,  
so I can't mess with the C code. We'd have to leave the extra methods in  
for a couple versions anyway, to prevent older code from breaking.)

The intermediate solution is to go to line 196 in Scintilla.pm (in the  
GetLine() sub) and take out the '+1'. Then when SaveFile calls GetLine,  
you won't get a trailing space.

The long-term solution is to find every place Laurent has used LineLength,  
and fix it. I am willing to do this and email the fixed file to someone  
with CVS access, so it will be correct in the next version. I'll test it  
via SaveFile, with differrent combinations of EOL markers in source and  
destination files, to make sure it really works. (I'll also fix that  
annoying little misspelling in the local variable while I'm at it.)



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