Use colors for some output messages

[andreynering]

This makes identifying specific types of messages easier.

• Green: commands
• Yellow: waning messages
• Red: error messages
• Magenta: debug information
• Etc

Output from commands will be kept untouched.

TODO:

• Add --color=false flag to disable this
• Disable color for version < 3
• Prettify task --list(skipping for now: tabwriter don't play nicely with colors)?

[stephenprater]

I'd like to see the colors exposed in Templater so that you we can control color in echoed strings. For instance, we have a task that does this:

<snip>
cmds:
  - echo "$(tput setaf 1) Press Ctrl-C now to cancel the deploy!"
  - sleep 5
  - task: deploy

It would be nice to expose the colors as format functions so you could do something similar to this:

  - echo "{{.RED}} Press Ctrl-C {{.BOLD}}NOW{{.DEFAULT}} to cancel the deploy"

[andreynering]

@stephenprater I think I'd prefer to have a different flag instead:

print:
  cmds:
    - cmd: echo "Something"
      color: red

This wouldn't solve the use case of having different colors on the same command, though.

[stephenprater]

Hmm - that's good point. Our use case was actually for the prefix string so it's easier to differentiate between tasks.

tasks:
   red_task:
      prefix: '{{.RED}} RED'
      cmds:
         - echo "something"

output would be like

[ RED ] something

Where "RED" is in red.

But the more that I think about it, the less I want to expose a plethora of special variables. Maybe a function that does something like: {{ color('red') }} instead?

[andreynering]

@stephenprater Yeah, we need to mature that idea first.

I gonna finish this PR at some point, and you're free to open another issue with a proposal if you come with a good one. 🙂

[wdscxsj]

Color not working on Windows with 3.0 preview 4?

[andreynering]

@wdscxsj Have you changed your Taskfile from version: 2 to version: 3?

[wdscxsj]

@andreynering Sure. Here is the effect on my machine (Windows 10 64-bit):

[andreynering]

@wdscxsj It may be a Windows-specific issue. Can you open another issue for tracking?

Also, does it also happens on v2?

[wdscxsj]

@andreynering Sure, please see #343.