"Edit right/left file" do not work with `EDITOR=vim`, or any other console editor

[phil-blain]

The command used to "Edit right file" or "Edit left" file is hardcoded to xterm -e vi if EDITOR is not set in the environment:

xxdiff/src/resources.cpp

Lines 335 to 341 in 50cb42b

	const char* editor = getenv( "EDITOR" );
	if ( editor != 0 ) {
	_commands[ CMD_EDIT ] = QString::fromLocal8Bit( editor );
	}
	else {
	_commands[ CMD_EDIT ] = "xterm -e vi";
	}

This is not ideal since EDITOR is meant (by old convention) to refer to a command-line editor like vi or vim, not a graphical program. When these xxdiff menu options are used with EDITOR=vim, nothing happens, which is very confusing. The error message at the end of XxApp::editFIle is not shown, because the if ( ! _editProc[bufIdx]->waitForStarted() ) block is not entered:

xxdiff/src/app.cpp

Lines 2723 to 2738 in 50cb42b

	if ( _editProc[bufIdx] == NULL ) {
	_editProc[bufIdx] = new QProcess;
	connect( _editProc[bufIdx], SIGNAL(finished(int,QProcess::ExitStatus)), SLOT(redoDiff()) );
	}
	_editProc[bufIdx]->start( executable, args );
	if ( ! _editProc[bufIdx]->waitForStarted() ) {
	QString text;
	{
	QTextStream oss( &text );
	oss << "There has been an error spawning the editor ("
	<< executable << "): "
	<< _editProc[bufIdx]->errorString() << Qt::endl;
	}
	new XxSuicideMessageBox(
	_mainWindow, "Error.", text, QMessageBox::Warning
	);

I didn't debug further, but it makes sense that invoking vim outside a terminal would not work. I would have expected the error message to be shown, though.

[blais]

This project is almost 25 years old and I haven't changed it in a while - years (I use tmux-based console diffing tools more these days). You're welcome to send me a patch; unless it looks egregiously bad I will rubberstamp it.