Function highlightLine

src/utils/codeHighlight.js:193–243

(text, uri, symbolName = null)

 * @param {string|null} symbolName - Optional symbol to highlight with special styling
 */
export async function highlightLine(text, uri, symbolName = null) {
	if (!text || !text.trim()) return "";

	const themeId = settings?.value?.editorTheme || "one_dark";
	const cacheKey = `line:${themeId}:${uri}:${text}:${symbolName || ""}`;

	if (highlightCache.has(cacheKey)) {
		return highlightCache.get(cacheKey);
	}

	const trimmedText = text.trim();

	try {
		const parser = await getLanguageParser(uri);
		if (parser) {
			const tree = parser.parse(trimmedText);
			let result = "";

			highlightCode(
				trimmedText,
				tree,
				classHighlighter,
				(code, classes) => {
					if (classes) {
						result += `<span class="${classes}">${escapeHtml(code)}</span>`;
					} else {
						result += escapeHtml(code);
					}
				},
				() => {},
			);

			if (result) {
				const highlighted = symbolName
					? addSymbolHighlight(result, symbolName)
					: result;
				setCache(cacheKey, highlighted);
				return highlighted;
			}
		}
	} catch (e) {
		console.warn("Highlighting failed for", uri, e);
	}

	const escaped = escapeHtml(trimmedText);
	const highlighted = symbolName
		? addSymbolHighlight(escaped, symbolName)
		: escaped;
	setCache(cacheKey, highlighted);
	return highlighted;
}

/**
 * Highlights a code block for display in markdown/plugin pages