github.com/abdfnx/gh-api@v0.0.0-20210414084727-f5432eec23b8/pkg/surveyext/editor.go (about)

     1  package surveyext
     2  
     3  // This file extends survey.Editor to give it more flexible behavior. For more context, read
     4  // https://github.com/cli/cli/issues/70
     5  // To see what we extended, search through for EXTENDED comments.
     6  
     7  import (
     8  	"os"
     9  	"path/filepath"
    10  	"runtime"
    11  
    12  	"github.com/AlecAivazis/survey/v2"
    13  	"github.com/AlecAivazis/survey/v2/terminal"
    14  )
    15  
    16  var (
    17  	bom           = []byte{0xef, 0xbb, 0xbf}
    18  	defaultEditor = "nano" // EXTENDED to switch from vim as a default editor
    19  )
    20  
    21  func init() {
    22  	if runtime.GOOS == "windows" {
    23  		defaultEditor = "notepad"
    24  	} else if g := os.Getenv("GIT_EDITOR"); g != "" {
    25  		defaultEditor = g
    26  	} else if v := os.Getenv("VISUAL"); v != "" {
    27  		defaultEditor = v
    28  	} else if e := os.Getenv("EDITOR"); e != "" {
    29  		defaultEditor = e
    30  	}
    31  }
    32  
    33  // EXTENDED to enable different prompting behavior
    34  type GhEditor struct {
    35  	*survey.Editor
    36  	EditorCommand string
    37  	BlankAllowed  bool
    38  }
    39  
    40  func (e *GhEditor) editorCommand() string {
    41  	if e.EditorCommand == "" {
    42  		return defaultEditor
    43  	}
    44  
    45  	return e.EditorCommand
    46  }
    47  
    48  // EXTENDED to change prompt text
    49  var EditorQuestionTemplate = `
    50  {{- if .ShowHelp }}{{- color .Config.Icons.Help.Format }}{{ .Config.Icons.Help.Text }} {{ .Help }}{{color "reset"}}{{"\n"}}{{end}}
    51  {{- color .Config.Icons.Question.Format }}{{ .Config.Icons.Question.Text }} {{color "reset"}}
    52  {{- color "default+hb"}}{{ .Message }} {{color "reset"}}
    53  {{- if .ShowAnswer}}
    54    {{- color "cyan"}}{{.Answer}}{{color "reset"}}{{"\n"}}
    55  {{- else }}
    56    {{- if and .Help (not .ShowHelp)}}{{color "cyan"}}[{{ .Config.HelpInput }} for help]{{color "reset"}} {{end}}
    57    {{- if and .Default (not .HideDefault)}}{{color "white"}}({{.Default}}) {{color "reset"}}{{end}}
    58  	{{- color "cyan"}}[(e) to launch {{ .EditorCommand }}{{- if .BlankAllowed }}, enter to skip{{ end }}] {{color "reset"}}
    59  {{- end}}`
    60  
    61  // EXTENDED to pass editor name (to use in prompt)
    62  type EditorTemplateData struct {
    63  	survey.Editor
    64  	EditorCommand string
    65  	BlankAllowed  bool
    66  	Answer        string
    67  	ShowAnswer    bool
    68  	ShowHelp      bool
    69  	Config        *survey.PromptConfig
    70  }
    71  
    72  // EXTENDED to augment prompt text and keypress handling
    73  func (e *GhEditor) prompt(initialValue string, config *survey.PromptConfig) (interface{}, error) {
    74  	err := e.Render(
    75  		EditorQuestionTemplate,
    76  		// EXTENDED to support printing editor in prompt and BlankAllowed
    77  		EditorTemplateData{
    78  			Editor:        *e.Editor,
    79  			BlankAllowed:  e.BlankAllowed,
    80  			EditorCommand: filepath.Base(e.editorCommand()),
    81  			Config:        config,
    82  		},
    83  	)
    84  	if err != nil {
    85  		return "", err
    86  	}
    87  
    88  	// start reading runes from the standard in
    89  	rr := e.NewRuneReader()
    90  	_ = rr.SetTermMode()
    91  	defer func() { _ = rr.RestoreTermMode() }()
    92  
    93  	cursor := e.NewCursor()
    94  	cursor.Hide()
    95  	defer cursor.Show()
    96  
    97  	for {
    98  		// EXTENDED to handle the e to edit / enter to skip behavior + BlankAllowed
    99  		r, _, err := rr.ReadRune()
   100  		if err != nil {
   101  			return "", err
   102  		}
   103  		if r == 'e' {
   104  			break
   105  		}
   106  		if r == '\r' || r == '\n' {
   107  			if e.BlankAllowed {
   108  				return "", nil
   109  			} else {
   110  				continue
   111  			}
   112  		}
   113  		if r == terminal.KeyInterrupt {
   114  			return "", terminal.InterruptErr
   115  		}
   116  		if r == terminal.KeyEndTransmission {
   117  			break
   118  		}
   119  		if string(r) == config.HelpInput && e.Help != "" {
   120  			err = e.Render(
   121  				EditorQuestionTemplate,
   122  				EditorTemplateData{
   123  					// EXTENDED to support printing editor in prompt, BlankAllowed
   124  					Editor:        *e.Editor,
   125  					BlankAllowed:  e.BlankAllowed,
   126  					EditorCommand: filepath.Base(e.editorCommand()),
   127  					ShowHelp:      true,
   128  					Config:        config,
   129  				},
   130  			)
   131  			if err != nil {
   132  				return "", err
   133  			}
   134  		}
   135  		continue
   136  	}
   137  
   138  	stdio := e.Stdio()
   139  	text, err := Edit(e.editorCommand(), e.FileName, initialValue, stdio.In, stdio.Out, stdio.Err, cursor)
   140  	if err != nil {
   141  		return "", err
   142  	}
   143  
   144  	// check length, return default value on empty
   145  	if len(text) == 0 && !e.AppendDefault {
   146  		return e.Default, nil
   147  	}
   148  
   149  	return text, nil
   150  }
   151  
   152  // EXTENDED This is straight copypasta from survey to get our overridden prompt called.;
   153  func (e *GhEditor) Prompt(config *survey.PromptConfig) (interface{}, error) {
   154  	initialValue := ""
   155  	if e.Default != "" && e.AppendDefault {
   156  		initialValue = e.Default
   157  	}
   158  	return e.prompt(initialValue, config)
   159  }
   160  
   161  func DefaultEditorName() string {
   162  	return filepath.Base(defaultEditor)
   163  }