1 files changed, 141 insertions, 0 deletions
diff --git a/internal/cli/remote_test.go b/internal/cli/remote_test.go
new file mode 100644
index 0000000..b4e20d9
--- /dev/null
+++ b/internal/cli/remote_test.go
@@ -0,0 +1,141 @@
+package cli
+
+import (
+	"sort"
+	"strings"
+	"testing"
+)
+
+func dir(path string) remoteEntry {
+	return remoteEntry{path: path, isDir: true, orderKey: pathOrderKey(path)}
+}
+func file(path string) remoteEntry {
+	return remoteEntry{path: path, orderKey: pathOrderKey(path)}
+}
+
+func deleted(e remoteEntry) remoteEntry {
+	e.deleted = true
+	return e
+}
+
+func emptyDirPaths(entries []remoteEntry) []string {
+	// Reproduce the production ordering (see listRemoteEntries) so the sort rule
+	// and the emptyDirs scan rule are always exercised together, rather than
+	// trusting hand-ordered literals.
+	sort.Slice(entries, func(i, j int) bool {
+		return entries[i].orderKey < entries[j].orderKey
+	})
+	got := emptyDirs(entries)
+	paths := make([]string, len(got))
+	for i, e := range got {
+		paths[i] = e.path
+	}
+	sort.Strings(paths)
+	return paths
+}
+
+func TestEmptyDirs(t *testing.T) {
+	tests := []struct {
+		name    string
+		entries []remoteEntry
+		want    []string
+	}{
+		{
+			name: "dir with only a deleted file is empty",
+			entries: []remoteEntry{
+				dir("a"),
+				deleted(file("a/gone.js")),
+			},
+			want: []string{"a"},
+		},
+		{
+			name: "dir with a surviving file is kept",
+			entries: []remoteEntry{
+				dir("a"),
+				file("a/live.js"),
+			},
+			want: []string{},
+		},
+		{
+			name: "bottom-up cascade removes parent and child",
+			entries: []remoteEntry{
+				dir("a"),
+				dir("a/b"),
+				deleted(file("a/b/gone.js")),
+			},
+			want: []string{"a"},
+		},
+		{
+			name: "deep file deleted but sibling file alive keeps parent",
+			entries: []remoteEntry{
+				dir("a"),
+				dir("a/b"),
+				deleted(file("a/b/gone.js")),
+				file("a/c.js"),
+			},
+			want: []string{"a/b"},
+		},
+		{
+			name: "sibling with shared name prefix is not swallowed",
+			entries: []remoteEntry{
+				dir("a"),
+				deleted(file("a/gone.js")),
+				file("ab/live.js"),
+			},
+			want: []string{"a"},
+		},
+		{
+			name: "sibling colliding on base name does not hide live children",
+			entries: []remoteEntry{
+				dir("a"),
+				file("a.js"),
+				file("a/live.js"),
+			},
+			want: []string{},
+		},
+		{
+			name: "empty dir with no children is removed",
+			entries: []remoteEntry{
+				dir("a"),
+			},
+			want: []string{"a"},
+		},
+		{
+			name: "nested dirs with no files at all are all removed",
+			entries: []remoteEntry{
+				dir("a"),
+				dir("a/b"),
+				dir("a/c"),
+			},
+			want: []string{"a"},
+		},
+		{
+			name: "empty dir nested under a dir holding a live file keeps outer, removes inner",
+			entries: []remoteEntry{
+				dir("a"),
+				dir("a/b"),
+				dir("a/b/c"),
+				file("a/live.js"),
+			},
+			want: []string{"a/b"},
+		},
+		{
+			name: "live file under a nested dir keeps the whole chain",
+			entries: []remoteEntry{
+				dir("a"),
+				dir("a/b"),
+				file("a/b/live.js"),
+			},
+			want: []string{},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got := emptyDirPaths(tt.entries)
+			if strings.Join(got, ",") != strings.Join(tt.want, ",") {
+				t.Fatalf("emptyDirs = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}