Search matchBackground isn't working in dom renderer

[Tyriar]

Repro:

Set matchBackground in client.ts to #ff0000 and use the search addon to find something with multiple matches.

Webgl:

DOM:

[Tyriar]

@jerch this was due to the fast DOM renderer change, see microsoft/vscode#189600 for more info on the bug.

Pretty sure it's caused by merging cells before the decoration color is resolved as the bg and fg (not border) are rendered as part of the regular grid:

xterm.js/src/browser/renderer/dom/DomRendererRowFactory.ts

Lines 214 to 234 in 18e578b

	// Apply any decoration foreground/background overrides, this must happen after inverse has
	// been applied
	let bgOverride: IColor | undefined;
	let fgOverride: IColor | undefined;
	let isTop = false;
	this._decorationService.forEachDecorationAtCell(x, row, undefined, d => {
	if (d.options.layer !== 'top' && isTop) {
	return;
	}
	if (d.backgroundColorRGB) {
	bgColorMode = Attributes.CM_RGB;
	bg = d.backgroundColorRGB.rgba >> 8 & 0xFFFFFF;
	bgOverride = d.backgroundColorRGB;
	}
	if (d.foregroundColorRGB) {
	fgColorMode = Attributes.CM_RGB;
	fg = d.foregroundColorRGB.rgba >> 8 & 0xFFFFFF;
	fgOverride = d.foregroundColorRGB;
	}
	isTop = d.options.layer === 'top';
	});

[Tyriar]

Another result of this:

Webgl:

DOM:

[jerch]

Yeah, seems this needs an exclusion from the merger.

[jerch]

@Tyriar Is there an easy way to test/repro this? Whats the desired behavior here?

[Tyriar]

@jerch setting matchBackground to something obvious in client.ts and then use the find previous textbox/button. Was pretty easy to repro for me. Only the search term should be highlighted, in this one only the t cells should have red backgrounds: