Added an option to add a comment to every select's option (#418)

Co-authored-by: Mislav Marohnić <[email protected]>

README.md

@@ -191,6 +191,22 @@ prompt := &survey.MultiSelect{..., PageSize: 10}
 
 // or as an option to Ask or AskOne
 survey.AskOne(prompt, &days, survey.WithPageSize(10))
+
+#### Select option's description
+
+```golang
+color := ""
+prompt := &survey.Select{
+    Message: "Choose a color:",
+    Options: []string{"red", "blue", "green"},
+    Description: func(value string, index int) string {
+        if value == "red" {
+            return "My favorite color"
+        }
+        return ""
+    },
+}
+survey.AskOne(prompt, &color)
 ```
 
 ### MultiSelect

examples/select_description.go

@@ -0,0 +1,47 @@
+package main
+
+import (
+	"fmt"
+
+	"github.com/AlecAivazis/survey/v2"
+)
+
+type Meal struct {
+	Title   string
+	Comment string
+}
+
+func main() {
+	var meals = []Meal{
+		{Title: "Bread", Comment: "Contains gluten"},
+		{Title: "Eggs", Comment: "Free-range"},
+		{Title: "Apple", Comment: ""},
+		{Title: "Burger", Comment: "Veggie patties available"},
+	}
+
+	titles := make([]string, len(meals))
+	for i, m := range meals {
+		titles[i] = m.Title
+	}
+	var qs = &survey.Select{
+		Message: "Choose a meal:",
+		Options: titles,
+		Description: func(value string, index int) string {
+			return meals[index].Comment
+		},
+	}
+
+	answerIndex := 0
+
+	// ask the question
+	err := survey.AskOne(qs, &answerIndex)
+
+	if err != nil {
+		fmt.Println(err.Error())
+		return
+	}
+
+	meal := meals[answerIndex]
+	// print the answers
+	fmt.Printf("you picked %s, nice choice.\n", meal.Title)
+}

select.go

@@ -28,6 +28,7 @@ type Select struct {
 	VimMode       bool
 	FilterMessage string
 	Filter        func(filter string, value string, index int) bool
+	Description   func(value string, index int) string
 	filter        string
 	selectedIndex int
 	useDefault    bool
@@ -42,6 +43,7 @@ type SelectTemplateData struct {
 	Answer        string
 	ShowAnswer    bool
 	ShowHelp      bool
+	Description   func(value string, index int) string
 	Config        *PromptConfig
 
 	// These fields are used when rendering an individual option
@@ -57,10 +59,17 @@ func (s SelectTemplateData) IterateOption(ix int, opt core.OptionAnswer) interfa
 	return copy
 }
 
+func (s SelectTemplateData) GetDescription(opt core.OptionAnswer) string {
+	if s.Description == nil {
+		return ""
+	}
+	return s.Description(opt.Value, opt.Index)
+}
+
 var SelectQuestionTemplate = `
 {{- define "option"}}
     {{- if eq .SelectedIndex .CurrentIndex }}{{color .Config.Icons.SelectFocus.Format }}{{ .Config.Icons.SelectFocus.Text }} {{else}}{{color "default"}}  {{end}}
-    {{- .CurrentOpt.Value}}
+    {{- .CurrentOpt.Value}}{{ if ne ($.GetDescription .CurrentOpt) "" }} - {{color "cyan"}}{{ $.GetDescription .CurrentOpt }}{{end}}
     {{- color "reset"}}
 {{end}}
 {{- if .ShowHelp }}{{- color .Config.Icons.Help.Format }}{{ .Config.Icons.Help.Text }} {{ .Help }}{{color "reset"}}{{"\n"}}{{end}}
@@ -171,6 +180,7 @@ func (s *Select) OnChange(key rune, config *PromptConfig) bool {
 		Select:        *s,
 		SelectedIndex: idx,
 		ShowHelp:      s.showingHelp,
+		Description:   s.Description,
 		PageEntries:   opts,
 		Config:        config,
 	}
@@ -257,6 +267,7 @@ func (s *Select) Prompt(config *PromptConfig) (interface{}, error) {
 	tmplData := SelectTemplateData{
 		Select:        *s,
 		SelectedIndex: idx,
+		Description:   s.Description,
 		ShowHelp:      s.showingHelp,
 		PageEntries:   opts,
 		Config:        config,
@@ -340,10 +351,11 @@ func (s *Select) Cleanup(config *PromptConfig, val interface{}) error {
 	return s.Render(
 		SelectQuestionTemplate,
 		SelectTemplateData{
-			Select:     *s,
-			Answer:     val.(core.OptionAnswer).Value,
-			ShowAnswer: true,
-			Config:     config,
+			Select:      *s,
+			Answer:      val.(core.OptionAnswer).Value,
+			ShowAnswer:  true,
+			Description: s.Description,
+			Config:      config,
 		},
 	)
 }