The problem

VersionGitHubActionsOutput.write_if_possible is writing to $GITHUB_OUTPUT, but fails to add an end-of line afterwards.

If one tries to echo another variable to $GITHUB_OUTPUT, it is then added to the previous line instead of a new line, and can't be used later in the workflow.

Here are the command from the workflow:

And the printed output:

Adding echo "" >> $GITHUB_OUTPUT before the next echo to $GITHUB_OUTPUT solved the issue as a workaround.

Expected behavior

Semantic release should write properly to $GITHUB_OUTPUT, finding out where the issue lies is time-consuming since this happens in the background.

Returning "\n".join(f"{key}={value!s}" for key, value in outputs.items()) + "\n" in VersionGitHubActionsOutput.to_output_text solves the issue.

Context

Linux runner
semantic release v9.3.1
Looking at the latest version, the issue seems still present.