Rename vars to improve clarity

Author: jdsutherland

workspace/workspace.go

@@ -97,25 +97,25 @@ func (ws Workspace) Exercises() ([]Exercise, error) {
 
 // ExerciseDir determines the root directory of an exercise.
 // This is the directory that contains the exercise metadata file.
-func (ws Workspace) ExerciseDir(s string) (string, error) {
-	if !strings.HasPrefix(s, ws.Dir) {
+func (ws Workspace) ExerciseDir(dir string) (string, error) {
+	if !strings.HasPrefix(dir, ws.Dir) {
 		return "", errors.New("not in workspace")
 	}
 
-	path := s
+	currentDir := dir
 	for {
-		if path == ws.Dir {
+		if currentDir == ws.Dir {
 			return "", errMissingMetadata
 		}
-		if _, err := os.Lstat(path); os.IsNotExist(err) {
+		if _, err := os.Lstat(currentDir); os.IsNotExist(err) {
 			return "", err
 		}
-		if _, err := os.Lstat(filepath.Join(path, metadataFilepath)); err == nil {
-			return path, nil
+		if _, err := os.Lstat(filepath.Join(currentDir, metadataFilepath)); err == nil {
+			return currentDir, nil
 		}
-		if _, err := os.Lstat(filepath.Join(path, legacyMetadataFilename)); err == nil {
-			return path, nil
+		if _, err := os.Lstat(filepath.Join(currentDir, legacyMetadataFilename)); err == nil {
+			return currentDir, nil
 		}
-		path = filepath.Dir(path)
+		currentDir = filepath.Dir(currentDir)
 	}
 }