Add sources special var

[hernandanielg]

Fixes #948

This is my attempt to implement the sources special variable, it does the trick but I am unsure if it should be this way... please provide some feedback ;)

Example test

$ cat ./testdata/special_vars/Taskfile.yml
tasks:
  default:
    cmds:
      - task: print
      - task: included:print

  print:
    cmds:
      - echo root/TASK={{.TASK}}
      - echo root/ROOT_DIR={{.ROOT_DIR}}
      - echo root/TASKFILE_DIR={{.TASKFILE_DIR}}
      - echo root/TASK_VERSION="{{.TASK_VERSION}}"
      - echo root/SOURCES="{{.SOURCES}}"
    sources:
     - '*.sh'

$ go run ./cmd/task --dir ./testdata/special_vars/ -f print
task: [print] echo root/TASK=print
root/TASK=print
task: [print] echo root/ROOT_DIR=/Users/hernandanielg/src/task/testdata/special_vars
root/ROOT_DIR=/Users/hernandanielg/src/task/testdata/special_vars
task: [print] echo root/TASKFILE_DIR=/Users/hernandanielg/src/task/testdata/special_vars
root/TASKFILE_DIR=/Users/hernandanielg/src/task/testdata/special_vars
task: [print] echo root/TASK_VERSION="(devel)"
root/TASK_VERSION=(devel)
task: [print] echo root/SOURCES="install-task.sh"
root/SOURCES=install-task.sh

$ go test -run ^TestSpecialVars$ github.com/go-task/task/v3

=== RUN   TestSpecialVars
--- PASS: TestSpecialVars (0.02s)
PASS
ok      github.com/go-task/task/v3      0.206s


> Test run finished at 5/2/2023, 7:03:21 AM <

[andreynering]

Hi @hernandanielg, thanks for this PR!

As I mentioned on this comment #948 (comment) I think this variable should probably be a slice/array of strings, instead of a string.

This way, the user can use slim-sprig to manipulate the list however they want, adding more flexibility to this variable.

[hernandanielg]

Hey @andreynering

Thanks a lot for the review, would you please help me a bit giving me some insights (first tim contributor here)

I am confused because function func (c *CompilerV3) getSpecialVars(t *taskfile.Task) returns a (map[string]string, error) so that's why I couldn't return a slice of strings, Globs function returns a slice of strings already

The way slim-sprig works seems I should return a space-separated string, am I wrong?

So is this going in a good direction or I should do something different?

Cheers!

[andreynering]

For reference, as said on Discord, this may need some refactor work to support types other than string on the variables map.

There's this old issue about it: #140. In theory it would allow even users themselves to declare array, maps, etc.