ci: extract changelog for current version

.github/workflows/ci.yml

@@ -8,6 +8,7 @@ jobs:
   report:
     needs:
       - lint-aux
+      - extract-changelog
       - rustfmt
       - clippy
       - build-and-test
@@ -34,6 +35,17 @@ jobs:
       - name: Run auxilary lints
         run: ./ci/lint-aux.sh
 
+  extract-changelog:
+      - uses: actions/checkout@v4
+      - name: Extract changelog
+        run: ./ci/extract-changelog.sh
+      - name: Upload artifact
+        uses: actions/upload-artifact@v4
+        with:
+          name: version-changelog
+          path: version-changelog
+          if-no-files-found: error
+
   rustfmt:
     runs-on: ubuntu-20.04
     steps:

ci/extract_changelog.sh

@@ -0,0 +1,24 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+. ci/utils.sh
+
+trim_empty_lines() {
+  awk 'NF { x = 1 } x' | tac | awk 'NF { x = 1 } x' | tac
+}
+
+version="$(crate_version rsjsonnet)"
+version="${version%-pre}"
+
+input_file="CHANGELOG.md"
+output_file="version-changelog"
+
+awk_script='/^##[^#]/ { if (x) { exit }; if ($2 == ver) { x = 1; next } } x'
+awk -v ver="$version" "$awk_script" "$input_file" | trim_empty_lines > "$output_file"
+
+if [ ! -s "$output_file" ]; then
+  echo "Changelog for version $version is empty"
+  exit 1
+fi
+
+echo "Extracted changelog for version $version"

version_changelog

@@ -0,0 +1 @@
+- Initial release