TextEditorDocument.findMatches ranges off by one

[colin-grant-work]

Bug Description:

The matches returned by the findMatches method of a TextEditorDocument are off by one (higher on each axis) relative to the selection behavior of an editor widget.

Using this code:

            const editorWidget = await this.editorManager.getOrCreateByUri(tasksJSONUri);
            const range = editorWidget.editor.document.findMatches?.({
                searchString: '"should highlight this"',
                isRegex: false,
                matchCase: true,
                matchWholeWord: false,
                limitResultCount: 1,
            })[0]?.range;

            this.editorManager.open(tasksJSONUri, { selection: range });

I expected the string "should highlight this" to be highlighted, but instead I got this:

Steps to Reproduce:

1. Create a text document with at least two lines and some text on each line.
2. Access the editor programmatically and use findMatches as illustrated above.
3. Open the editor with a {selection} or open the editor and set editor.selection = range
4. Observe that the wrong line is highlighted, and the highlighting is one character to the right of where it should be.

Additional Information

• Operating System: RHEL, browser mode (Chrome)
• Theia Version: 1.10.0

[vince-fugnitto]

I noticed the same thing when I proposed a snippet to one of our questions (I had to increase the start line-number to get the proper line): #9041 (reply in thread)

I need to confirm that documents are 0 based:

• Fix off-by-one error in vscode.window.showTextDocument #7310 (comment)

[colin-grant-work]

Similar behavior occurs with the NPM builtin plugin:

clean is selected, and should be highlighted, but the line-highlight falls on lint instead.

[colin-grant-work]

There's also code in the in the plugin system making different assumptions about this:

Assumes that our ranges and VSCode's ranges won't agree:

theia/packages/plugin-ext/src/plugin/type-converters.ts

Lines 111 to 134 in bd12178

	export function toRange(range: model.Range): types.Range {
	// if (!range) {
	// return undefined;
	// }
	const { startLineNumber, startColumn, endLineNumber, endColumn } = range;
	return new types.Range(startLineNumber - 1, startColumn - 1, endLineNumber - 1, endColumn - 1);
	}
	export function fromRange(range: undefined): undefined;
	export function fromRange(range: theia.Range): model.Range;
	export function fromRange(range: theia.Range | undefined): model.Range | undefined;
	export function fromRange(range: theia.Range | undefined): model.Range | undefined {
	if (!range) {
	return undefined;
	}
	const { start, end } = range;
	return {
	startLineNumber: start.line + 1,
	startColumn: start.character + 1,
	endLineNumber: end.line + 1,
	endColumn: end.character + 1
	};
	}

Assumes that our ranges and VSCode's ranges will agree:

theia/packages/plugin-ext/src/main/browser/callhierarchy/callhierarchy-type-converters.ts

Lines 54 to 66 in 112d724

	export function fromRange(range: callhierarchy.Range): model.Range {
	const { start, end } = range;
	return {
	startLineNumber: start.line,
	startColumn: start.character,
	endLineNumber: end.line,
	endColumn: end.character
	};
	}
	export function toRange(range: model.Range): callhierarchy.Range {
	return callhierarchy.Range.create(range.startLineNumber, range.startColumn, range.endLineNumber, range.endColumn);
	}

theia/packages/plugin-ext/src/plugin/languages/call-hierarchy.ts

Lines 70 to 86 in 112d724

	private fromRange(range: theia.Range): model.Range {
	return {
	startLineNumber: range.start.line,
	startColumn: range.start.character,
	endLineNumber: range.end.line,
	endColumn: range.end.character
	};
	}
	private toRange(range: model.Range): types.Range {
	return new types.Range(
	range.startLineNumber,
	range.startColumn,
	range.endLineNumber,
	range.endColumn
	);
	}

There may be some confusion here on my part (it looks like three different range types may be in play, two of which agree and one of which disagrees?), but three different definition of Range is a problem of its own....