Add release changelog

Author: max-arnold

.github/workflows/build.yml

@@ -18,7 +18,7 @@ on:
   workflow_dispatch:
     inputs:
       revision:
-        description: "The tag to release, e.g. v1.00"
+        description: "A tag to release, e.g. v1.00"
         type: string
         required: false
 
@@ -119,8 +119,10 @@ jobs:
         env:
           GITHUB_TOKEN: ${{ github.token }}
           SLUG: ${{ needs.build.outputs.slug }}
-        run: |
-          gh release create "$SLUG" --repo '${{ github.repository }}'
+        run: >-
+          cat CHANGELOG.md |
+          python -c 'import os,re,sys; t=sys.stdin.read(); r=re.search(f"""(^## {os.environ["SLUG"][1:].replace(".", "\\.")} .*?)(?=^## \\d|\\Z)""", t, re.MULTILINE | re.DOTALL); print(r.group(0) if r else "")' |
+          gh release create "$SLUG" --repo '${{ github.repository }}' --notes-file -
       - name: Upload release artifact
         env:
           GITHUB_TOKEN: ${{ github.token }}