Asking the same set of questions multiple times corrupts the output

[stoggi]

When asking multiple surveys but with the same question, the output is corrupted for the second survey. The cursor begins on the same line, and overwrites the previous question each time.

Environments Tested

OS: MacOS, Linux Terminal: iTerm2, xfce4-terminal Shell: bash, zsh, elvish Versions:

• github.com/AlecAivazis/survey/v2 v2.0.5
• github.com/AlecAivazis/survey/v2 v2.0.6-0.20200121083222-e4745b24cd43

Example

package main

import (
    "fmt"

    "github.com/AlecAivazis/survey/v2"
)

type Answers struct {
    Name    string
    Age     int
    Hobbies string
}

var questions = []*survey.Question{
    {
        Name:     "Name",
        Prompt:   &survey.Input{Message: "What's your name?"},
        Validate: survey.Required,
    },
    {
        Name:     "Age",
        Prompt:   &survey.Input{Message: "How old are you?"},
        Validate: survey.Required,
    },
    {
        Name:     "Hobbies",
        Prompt:   &survey.Input{Message: "What are your hobbies?"},
        Validate: survey.Required,
    },
}

func main() {
    a1 := Answers{}
    if err := survey.Ask(questions, &a1); err != nil {
        panic(err)
    }
    a2 := Answers{}
    if err := survey.Ask(questions, &a2); err != nil {
        panic(err)
    }
    fmt.Println(a1, a2)
}

Observed output:

What was I expecting to see?

The second survey should appear like the first, instead newlines seem to get lost, and it overwrites the same line for each question.

[stoggi]

After a little more digging, it seems this is because I'm asking the same questions multiple times!

This code is not affected:

package main

import (
    "fmt"

    "github.com/AlecAivazis/survey/v2"
)

type Answers struct {
    Name    string
    Age     int
    Hobbies string
}

var questions1 = []*survey.Question{
    {
        Name:     "Name",
        Prompt:   &survey.Input{Message: "What's your name?"},
        Validate: survey.Required,
    },
    {
        Name:     "Age",
        Prompt:   &survey.Input{Message: "How old are you?"},
        Validate: survey.Required,
    },
    {
        Name:     "Hobbies",
        Prompt:   &survey.Input{Message: "What are your hobbies?"},
        Validate: survey.Required,
    },
}

var questions2 = []*survey.Question{
    {
        Name:     "Name",
        Prompt:   &survey.Input{Message: "What's your name?"},
        Validate: survey.Required,
    },
    {
        Name:     "Age",
        Prompt:   &survey.Input{Message: "How old are you?"},
        Validate: survey.Required,
    },
    {
        Name:     "Hobbies",
        Prompt:   &survey.Input{Message: "What are your hobbies?"},
        Validate: survey.Required,
    },
}

func main() {
    a1 := Answers{}
    if err := survey.Ask(questions1, &a1); err != nil {
        panic(err)
    }
    a2 := Answers{}
    if err := survey.Ask(questions2, &a2); err != nil {
        panic(err)
    }
    fmt.Println(a1, a2)
}

This feels like some internal state is not being cleared.

[mislav]

@stoggi Excellent sleuthing! It looks like some state is being remembered between these prompts that results in extra lines of output being overwritten.

[li-jin-gou]

I had the same problem.