command and help ux pass (#21)

Reviewed-on: #21
Co-authored-by: vickydotbat <vickydotbat@tutamail.com>
Co-committed-by: vickydotbat <vickydotbat@tutamail.com>

internal/menu/menu_test.go

@@ -1,8 +1,10 @@
 package menu
 
 import (
+	"bytes"
 	"io"
 	"reflect"
+	"regexp"
 	"strings"
 	"testing"
 )
@@ -45,3 +47,58 @@ func TestSelectInvalidErrors(t *testing.T) {
 		t.Fatal("out-of-range selection should error")
 	}
 }
+
+func TestSelectAlignsDescriptionsAfterLongestLabel(t *testing.T) {
+	items := []Item{
+		{Label: "hak build", Desc: "build haks", Args: []string{"hak", "build"}},
+		{Label: "topdata exceptionally-long-command", Desc: "long command", Args: []string{"topdata", "long"}},
+	}
+	var out bytes.Buffer
+	if _, err := Select(&out, strings.NewReader("q\n"), items); err != nil {
+		t.Fatalf("select: %v", err)
+	}
+	text := stripANSI(out.String())
+	var positions []int
+	for _, line := range strings.Split(text, "\n") {
+		for _, desc := range []string{"build haks", "long command"} {
+			if index := strings.Index(line, desc); index >= 0 {
+				positions = append(positions, index)
+			}
+		}
+	}
+	if len(positions) != 2 {
+		t.Fatalf("expected two menu descriptions, got %d:\n%s", len(positions), text)
+	}
+	if positions[0] != positions[1] {
+		t.Fatalf("descriptions are not aligned: columns %v\n%s", positions, text)
+	}
+}
+
+func TestSelectShowsCommandGuidanceBeforeArgumentsPrompt(t *testing.T) {
+	items := []Item{{
+		Label:   "topdata build",
+		Desc:    "compile topdata",
+		Args:    []string{"topdata", "build"},
+		Usage:   "crucible topdata build [--force]",
+		Options: []string{"--force   rebuild outputs"},
+	}}
+	var out bytes.Buffer
+	if _, err := Select(&out, strings.NewReader("1\n\n"), items); err != nil {
+		t.Fatalf("select: %v", err)
+	}
+	text := stripANSI(out.String())
+	for _, want := range []string{
+		"usage: crucible topdata build [--force]",
+		"options:",
+		"--force   rebuild outputs",
+		"arguments (press Enter to use defaults):",
+	} {
+		if !strings.Contains(text, want) {
+			t.Errorf("selected command guidance missing %q:\n%s", want, text)
+		}
+	}
+}
+
+func stripANSI(value string) string {
+	return regexp.MustCompile(`\x1b\[[0-9;]*m`).ReplaceAllString(value, "")
+}