Index backend commands for path lookup

internal/cobra/parse_test.go

@@ -2,6 +2,7 @@ package cobra
 
 import (
 	"context"
+	"fmt"
 	"io"
 	"reflect"
 	"strings"
@@ -130,3 +131,51 @@ func TestParseReturnsNeutralFailuresAndFreshState(t *testing.T) {
 		t.Fatalf("unknown flag failure = %#v", failed.Failure)
 	}
 }
+
+func TestSelectedPathsResolveThroughBackendParents(t *testing.T) {
+	root := &Command{Name: "app"}
+	for index := 0; index < 128; index++ {
+		root.Children = append(root.Children, &Command{Name: fmt.Sprintf("wide%03d", index), Runnable: true})
+	}
+	path := make([]string, 24)
+	current := root
+	for index := range path {
+		path[index] = fmt.Sprintf("deep%02d", index)
+		child := &Command{Name: path[index]}
+		if index == len(path)-1 {
+			child.Runnable = true
+		}
+		current.Children = append(current.Children, child)
+		current = child
+	}
+
+	result := Parse(root, path, ParseOptions{})
+	if result.Failure != nil || !reflect.DeepEqual(result.Path, path) {
+		t.Fatalf("deep parse path = %#v", result)
+	}
+	rootResult := Parse(root, nil, ParseOptions{})
+	if rootResult.Failure != nil || len(rootResult.Path) != 0 {
+		t.Fatalf("root parse path = %#v", rootResult)
+	}
+
+	help, failure := RenderHelp(root, path)
+	if failure != nil || !strings.Contains(help, path[len(path)-1]) {
+		t.Fatalf("deep help = %q, %v", help, failure)
+	}
+	if _, failure := RenderHelp(root, []string{"wide128"}); failure == nil {
+		t.Fatal("help accepted an unknown sibling")
+	}
+	line, failure := UsageLine(root, path)
+	if failure != nil || !strings.Contains(line, path[len(path)-1]) {
+		t.Fatalf("deep usage line = %q, %v", line, failure)
+	}
+	if _, failure := UsageLine(root, []string{"wide128"}); failure == nil {
+		t.Fatal("usage accepted an unknown sibling")
+	}
+	if _, failure := RenderHelp(root, nil); failure != nil {
+		t.Fatalf("root help failed: %v", failure)
+	}
+	if _, failure := UsageLine(root, nil); failure != nil {
+		t.Fatalf("root usage failed: %v", failure)
+	}
+}