Function resolveRelativePath

lib/lbt/utils/ModuleName.js:68–117

(path, relativePath)

const SPECIAL_PATH_SEGMENT = /^\.+$/;

export function resolveRelativePath(path, relativePath) {
	// while has segment
	//	 if ( segment == . )
	//			ignore segment
	//	 else if segment == ..
	//			remove one segment from stack, throw exception if there is none
	//	 else
	//			add segment to stack
	// combine segments in stack with '/'

	const match = ANY_SPECIAL_PATH_SEGMENT.exec(relativePath);
	if ( match ) {
		// process segments only if there is at least one special segment
		let segments = [];

		const p = path.lastIndexOf("/");
		if ( match.index == 0 && p > 0 ) {
			// if first segment is ./ or ../, start with parent path, otherwise start empty
			segments = path.slice(0, p).split("/");
		}

		const relativePathSegments = relativePath.split("/");
		for ( let i = 0; i < relativePathSegments.length; i++ ) {
			const segment = relativePathSegments[i];
			if ( SPECIAL_PATH_SEGMENT.test(segment) ) {
				switch ( segment.length ) {
				case 1:
					// segment './' -> ignore
					continue;
				case 2:
					// segment '../' -> navigate to parent if possible
					if ( segments.length === 0 ) {
						throw new Error(`Can't navigate to parent of root (${path}, ${relativePath})`);
					}
					segments.pop();
					break;
				default:
					// segment '...' or more dots: not allowed
					throw new Error(`Illegal path segment '${segment}'`);
				}
			} else {
				// normal segment: add
				segments.push(segment);
			}
		}
		// console.log("resolution of (%s,%s): %s%n", getPackagePath(), relativePath, StringUtils.join(segments, "/"));
		relativePath = segments.join("/");
	}
	return relativePath;
}

export function resolveRelativeRequireJSName(path, relativeName) {
	return resolveRelativePath(path, relativeName + ".js");