v3: expansion doesn't work as expected

[kovetskiy]

I'm using latest version of v3 branch

Taskfile.yml

version: '3'

vars:
  root: 'x'
  exp: 'exp-{{.root}}'

tasks:
  test:
    desc: a
    cmds:
      - echo root is '{{.root}}'
      - echo but exp is '{{.exp}}'

Current output:

$ task test root=y
task: echo root is 'y'
root is y
task: echo but exp is 'exp-x'
but exp is exp-x

$ task root=y test
task: echo root is 'y'
root is y
task: echo but exp is 'exp-y'
but exp is exp-y

Expected: both variants should output the same — exp variable should be exp-y because root is y.

[andreynering]

Hi @kovetskiy, thanks for opening this issue!

I did some testing and found this also happen in v2.

I'm not sure if this is really a bug or a by design behavior of how variables work (their priority, etc)

I plan to take a look at this before the v3 release, though...

[kovetskiy]

@andreynering yes, the same on v2, but I thought v3 was going to address this nasty issue. It's very ambiguous to see such behavior.
Imagine my user case: I have a task that creates docker container of an image with specified version and I print a message like:
echo creating docker container with version {{.version}}
I also defined image: "backend/server:{{.version}}" and run something like docker run --name backend-server-{{.version}} {{.image}}
As result I have a message that task is going to create a container of correct version but ends up with an incorrect one.

On the other hand, GNU's make doesn't care about variables' order and just sets variables values to what users have specified.