Add generate-pending-release-diffs command

bin/generate-pending-release-diffs.sh

@@ -0,0 +1,59 @@
+#!/bin/bash
+# Generate an overview of the plugin changes between the local filesystem and the latest stable (trunk) versions
+# committed to SVN in the WordPress.org Plugin Directory. The output is in Markdown format which is suitable for
+# pasting into a GitHub release preparation PR. Program status updates are sent to STDERR, so STDOUT can be piped
+# either to the clipboard or to a file for posting to GitHub.
+#
+# USAGE:
+# ./generate-pending-release-diffs.sh > overview.md
+# ./generate-pending-release-diffs.sh | pbcopy
+# npm run generate-pending-release-diffs --silent
+
+set -e
+
+for required_command in npm git svn jq rsync; do
+	if ! command -v "$required_command" &> /dev/null; then
+		echo "Error: The $required_command command must be installed to use this script." >&2
+		exit 1
+	fi
+done
+
+cd "$(git rev-parse --show-toplevel)"
+
+npm run build:plugin:performance-lab >&2 # TODO: Remove this as of <https://github.com/WordPress/performance/pull/1182>.
+npm run build-plugins >&2
+
+stable_dir=/tmp/stable-svn
+mkdir -p "$stable_dir"
+for plugin_slug in $(jq '.plugins[]' -r plugins.json) 'performance-lab'; do
+	echo "# $plugin_slug ###############################" >&2
+	if [ ! -d "$stable_dir/$plugin_slug" ]; then
+		svn co "https://plugins.svn.wordpress.org/$plugin_slug/trunk/" "$stable_dir/$plugin_slug" >&2
+	else
+		svn revert "$stable_dir/$plugin_slug" >&2
+		svn up "$stable_dir/$plugin_slug" >&2
+	fi
+
+	rsync -avz --delete --exclude=".svn" "build/$plugin_slug/" "$stable_dir/$plugin_slug/" >&2
+
+	cd "$stable_dir/$plugin_slug/"
+
+	echo "# \`$plugin_slug\`"
+	echo
+	echo "\`svn status\`:"
+	echo '```'
+	svn status
+	echo '```'
+	echo
+	echo '<details><summary><code>svn diff</code></summary>'
+	echo
+	echo '```diff'
+	svn diff
+	echo '```'
+	echo '</details>'
+	echo
+
+	cd - > /dev/null
+
+	echo >&2
+done

package.json

@@ -38,6 +38,7 @@
     "build:plugin:optimization-detective": "webpack --mode production --env plugin=optimization-detective",
     "build:plugin:speculation-rules": "webpack --mode production --env plugin=speculation-rules",
     "build:plugin:webp-uploads": "webpack --mode production --env plugin=webp-uploads",
+    "generate-pending-release-diffs": "bin/generate-pending-release-diffs.sh",
     "format-js": "wp-scripts format",
     "lint-js": "wp-scripts lint-js",
     "format-php": "composer format",