dagger do: Improve help message

- Only print first line of comment
- Add "Available Options" section header

Fixes #1777

Signed-off-by: Andrea Luzzardi <aluzzardi@gmail.com>

cmd/dagger/cmd/do.go

@@ -128,13 +128,13 @@ func doHelpCmd(cmd *cobra.Command, _ []string) {
 		return
 	}
 
-	fmt.Println("")
+	fmt.Printf("\nAvailable Actions:\n")
 	w := tabwriter.NewWriter(os.Stdout, 0, 0, 1, ' ', tabwriter.StripEscape)
 	defer w.Flush()
 
 	for _, a := range action.Children {
 		if !a.Hidden {
-			lineParts := []string{"", a.Name, strings.TrimSpace(a.Comment)}
+			lineParts := []string{"", a.Name, a.Documentation}
 			fmt.Fprintln(w, strings.Join(lineParts, "\t"))
 		}
 	}

compiler/value.go

@@ -6,6 +6,7 @@ import (
 	"path/filepath"
 	"sort"
 	"strconv"
+	"strings"
 
 	"cuelang.org/go/cue"
 	"cuelang.org/go/cue/ast"
@@ -346,3 +347,16 @@ func (v *Value) Default() (*Value, bool) {
 func (v *Value) Doc() []*ast.CommentGroup {
 	return v.Cue().Doc()
 }
+
+// DocSummary returns the first line of documentation
+func (v *Value) DocSummary() string {
+	doc := ""
+	for _, c := range v.Doc() {
+		doc += c.Text()
+	}
+
+	doc = strings.TrimSpace(doc)
+	doc = strings.SplitN(doc, "\n", 2)[0]
+
+	return doc
+}

plan/action.go

@@ -5,12 +5,11 @@ import (
 )
 
 type Action struct {
-	Name     string
-	Hidden   bool
-	Path     cue.Path
-	Comment  string
-	Children []*Action
-	// pkg      string
+	Name          string
+	Hidden        bool
+	Path          cue.Path
+	Documentation string
+	Children      []*Action
 }
 
 func (a *Action) AddChild(c *Action) {

plan/plan.go

@@ -199,9 +199,7 @@ func (p *Plan) fillAction() {
 	if !actions.Exists() {
 		return
 	}
-	for _, cg := range actions.Doc() {
-		p.action.Comment += cg.Text()
-	}
+	p.action.Documentation = actions.DocSummary()
 
 	tasks := flow.Tasks()
 
@@ -214,17 +212,12 @@ func (p *Plan) fillAction() {
 			a := prevAction.FindByPath(path)
 			if a == nil {
 				v := p.Source().LookupPath(path)
-				childComment := ""
-				for _, cg := range v.Doc() {
-					childComment += cg.Text()
-				}
-
 				a = &Action{
-					Name:     s.String(),
-					Hidden:   s.PkgPath() != "",
-					Path:     path,
-					Comment:  childComment,
-					Children: []*Action{},
+					Name:          s.String(),
+					Hidden:        s.PkgPath() != "",
+					Path:          path,
+					Documentation: v.DocSummary(),
+					Children:      []*Action{},
 				}
 				prevAction.AddChild(a)
 			}