computed vars in dotenv paths

[rpf3]

Description

When a dotenv path references a variable computed via sh, the template renders incorrectly — the variable appears empty, causing the resolved path to fall back to the task's working directory.

Expected behavior

{{.DOTENV}} resolves to the output of mktemp and the dotenv file at that path is loaded.

Actual behavior

{{.DOTENV}} renders to an empty string. The empty path is resolved against the task's working directory.

$ task
task: Failed to read env file ...: read /home/user/project: is a directory

Related issues

• Dynamic .env file #434 — variable interpolation in dotenv: paths (implemented for static vars only)
• Updated Environment Variables Before Dotenv File #1912 — CLI-provided vars not visible in dotenv: paths (includes a sh: mktemp example; closed pointing to PR Fix handling of CLI provided global vars. #2288, which was not merged)
• {{.USER_WORKING_DIR}} evaluated after dotenv #1312 — {{.USER_WORKING_DIR}} not available in global dotenv: paths (closed with workarounds only)

Workaround

Avoid dotenv entirely and source the file explicitly in each task that needs it:

cmds:
  - |
    set -a && source {{.DOTENV}} && set +a

Version

3.48.0

Operating system

Ubuntu 20.04

Experiments Enabled

No response

Example Taskfile

version: '3'

vars:
  DOTENV:
    sh: mktemp

tasks:
  default:
    dotenv:
      - '{{.DOTENV}}'
    cmds:
      - echo "AWS_KEY=$AWS_KEY"

[rpf3]

If this is unintended, or intended but a possible feature addition, I'd like to assist in fixing/implementing.

[trulede]

In this PR, on the following line, you might be able to expand the path using the templater already created in the function. It should work.

https://github.com/go-task/task/pull/2711/changes#diff-88a1dcc1be6c418f7d053085cf094890a7a3e4f767c4f8500cf51373589e5bb9R89

If it does work (will be one line change I think) make a review with the suggestion. Add a test case too if you what, the PR already covers a few cases, so add yours.