Merge pull request #1379 from Victorystick/simpler-resolveId

Consolidate all non-null, `resolveId` return statements

src/utils/defaults.js

@@ -36,16 +36,16 @@ export function resolveId ( importee, importer ) {
 		});
 	}
 
-	// absolute paths are left untouched
-	if ( isAbsolute( importee ) ) return addJsExtensionIfNecessary( resolve( importee ) );
-
-	// if this is the entry point, resolve against cwd
-	if ( importer === undefined ) return addJsExtensionIfNecessary( resolve( process.cwd(), importee ) );
-
-	// external modules are skipped at this stage
-	if ( importee[0] !== '.' ) return null;
-
-	return addJsExtensionIfNecessary( resolve( dirname( importer ), importee ) );
+	// external modules (non-entry modules that start with neither '.' or '/')
+	// are skipped at this stage.
+	if ( importer !== undefined && !isAbsolute( importee ) && importee[0] !== '.' ) return null;
+
+	// `resolve` processes paths from right to left, prepending them until an
+	// absolute path is created. Absolute importees therefore shortcircuit the
+	// resolve call and require no special handing on our part.
+	// See https://nodejs.org/api/path.html#path_path_resolve_paths
+	return addJsExtensionIfNecessary(
+		resolve( importer ? dirname( importer ) : resolve(), importee ) );
 }