Add executeCommand Prompt

[marakalwa]

• PR Description

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[jesseduffield]

@marakalwa could you explain the use-case behind this PR?

[jwickers]

Hmm I was looking at a way to get the result of a command into an input initialValue, would this somehow allow that since initialValue could be "{{.Form.field}}" where field is the output of executeCommand ?

[marakalwa]

@marakalwa could you explain the use-case behind this PR?

Oh my, I did not want to create a pull request for this PR yet. Must have done that very sleepy, either very early or very late 😅

Hmm I was looking at a way to get the result of a command into an input initialValue, would this somehow allow that since initialValue could be "{{.Form.field}}" where field is the output of executeCommand ?

This is exactly the use case for this PR. Running a command without user interaction and saving the result for use in further inputs is imo absolutely vital for building powerful custom commands.

I will just use the relevant part of the customCommand that led me to create this change:

- key: 'i'
    context: 'commits'
    description: 'Change the commit date of this and all subsequent commits'
    prompts:
      - type: 'executeCommand'
        command: |
          date -r {{.SelectedLocalCommit.UnixTimestamp}} +"%a %b %d %H:%M:%S %Y %z" | tr -d "\n"
        key: 'CurrentTimeStamp'
      - type: 'input'
        title: 'What is the new timestamp? Old: {{.Form.CurrentTimeStamp}}'
        initialValue: '{{.Form.CurrentTimeStamp}}'
        key: 'TimeStamp'

As you can see I used an excecuteCommand prompt here to format the UnixTimeStamp of the SelectedLocalCommit in such a way that it is human readable/editable (and can later be read by git in the 'command' part). Without executeCommand this would (afaik) be impossible in this form and require at least two custom commands and the use of the clipboard to get anything close to this.

I have been running lazygit with this change for over a month with various customCommands using multiple executeCommand prompts without issue.

I will try to now finish this PR asap. Lmk if you think I did something wrong here :) and thank you for this awesome tool @jesseduffield

[jesseduffield]

Okay that makes sense, sounds reasonable. I'll review the code once you've completed the PR