Fixes https://github.com/go-gitea/gitea/issues/37286
Automatic release notes for the first release in a repository were empty
when there was no previous tag.
Before this change, the release notes generator used the tag name to
build the changelog link, but reused that state for pull request
collection. When `PreviousTag` was empty, the PR collection logic did
not scan a useful commit range, so merged pull requests were omitted
from the generated notes.
This pull request fixes that by decoupling the internal PR collection
range from the rendered changelog link:
- when a previous tag exists, behavior stays unchanged
- when no previous tag exists, release notes collect merged pull
requests from the full reachable history up to the target tag
- the displayed full changelog link for the first release still uses the
existing `/commits/tag/{tag}` format
Tests were updated to cover:
- generating notes for a repository with no previous tags
- including merged pull requests before the first tag
- preserving existing behavior when a previous tag exists
Similar to GitHub, release notes can now be generated automatically.
The generator is server-side and gathers the merged PRs and contributors
and returns the corresponding Markdown text.
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Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>
