status: display count of directories

fixes #112

src/artifact/artifact.go

@@ -85,26 +85,41 @@ type Status struct {
 	ChildrenStatus map[string]*Status
 }
 
-func (stat Status) childStatusCounts(out map[string]int) {
+func (stat Status) dirStatusCounts(counts map[string]int) {
+	// len(nil map) returns 0
+	if len(stat.ChildrenStatus) == 0 {
+		counts["empty directory"]++
+	} else {
+		counts["directory"]++
+	}
 	for _, childStatus := range stat.ChildrenStatus {
 		if childStatus.IsDir {
-			childStatus.childStatusCounts(out)
+			childStatus.dirStatusCounts(counts)
 		} else {
-			out[childStatus.String()]++
+			counts[childStatus.String()]++
 		}
 	}
 }
 
-func sortByValue(counts map[string]int) []string {
+func sortCounts(counts map[string]int) []string {
 	keys := make([]string, len(counts))
 	i := 0
 	for key := range counts {
 		keys[i] = key
 		i++
 	}
-	sort.Slice(keys, func(i, j int) bool {
-		// Sort into descending order.
-		return counts[keys[i]] > counts[keys[j]]
+	sort.Slice(keys, func(a, b int) bool {
+		aKey := keys[a]
+		aVal := counts[aKey]
+		bKey := keys[b]
+		bVal := counts[keys[b]]
+		// If the values are equal, fallback to lexicographic order of the
+		// string keys. This is primarily for writing deterministic tests.
+		if aVal == bVal {
+			return aKey < bKey
+		}
+		// Sort by highest value first.
+		return aVal > bVal
 	})
 	return keys
 }
@@ -166,15 +181,11 @@ func (stat Status) String() string {
 	}
 
 	if stat.IsDir {
-		// len(nil map) returns 0
-		if len(stat.ChildrenStatus) == 0 {
-			return "empty directory"
-		}
 		counts := make(map[string]int)
-		stat.childStatusCounts(counts)
+		stat.dirStatusCounts(counts)
 		countStrings := make([]string, len(counts))
-		for i, status := range sortByValue(counts) {
-			countStrings[i] = fmt.Sprintf("x%d %s", counts[status], status)
+		for i, status := range sortCounts(counts) {
+			countStrings[i] = fmt.Sprintf("%dx %s", counts[status], status)
 		}
 		return strings.Join(countStrings, ", ")
 	}

src/artifact/artifact_test.go

@@ -3,6 +3,7 @@ package artifact
 import (
 	"testing"
 
+	"github.com/google/go-cmp/cmp"
 	"github.com/kevin-hanselman/dud/src/fsutil"
 )
 
@@ -127,7 +128,7 @@ func TestArtifactStatusString(t *testing.T) {
 			},
 		}
 
-		want := "x3 up-to-date, x1 not committed"
+		want := "3x up-to-date, 2x directory, 1x not committed"
 
 		got := status.String()
 		if got != want {
@@ -144,14 +145,40 @@ func TestArtifactStatusString(t *testing.T) {
 			ContentsMatch:       false,
 		}
 
-		want := "empty directory"
+		want := "1x empty directory"
 
 		got := status.String()
 		if got != want {
 			t.Fatalf("Status.String() got %#v, want %#v", got, want)
 		}
 	})
 
+	t.Run("empty sub-directory", func(t *testing.T) {
+		status := Status{
+			Artifact:            Artifact{IsDir: true},
+			WorkspaceFileStatus: fsutil.StatusDirectory,
+			HasChecksum:         true,
+			ChecksumInCache:     true,
+			ContentsMatch:       false,
+			ChildrenStatus: map[string]*Status{
+				"c": {
+					Artifact:            Artifact{IsDir: true},
+					WorkspaceFileStatus: fsutil.StatusDirectory,
+					HasChecksum:         true,
+					ChecksumInCache:     true,
+					ContentsMatch:       false,
+				},
+			},
+		}
+
+		want := "1x directory, 1x empty directory"
+
+		got := status.String()
+		if diff := cmp.Diff(want, got); diff != "" {
+			t.Fatalf("Status.String() -want +got:\n%s", diff)
+		}
+	})
+
 	t.Run("directory but IsDir false", func(t *testing.T) {
 		status := Status{
 			Artifact:            Artifact{IsDir: false},