check-links: move review-comment sync to dev/sync-review-comments.sh; update comments whose text changed

Amp-Thread-ID: https://ampcode.com/threads/T-01a08fee-74b4-76dc-aaf9-d1245d68fdc9
Co-authored-by: Amp <amp@ampcode.com>

Author: marcleblanc2

.github/workflows/check-links.yml

@@ -97,34 +97,13 @@ jobs:
                   fi
 
             - name: Suggest fixes as review comments
-              # One suggested change per finding with a fix. Suggestions already on the
-              # PR (same file, line, and link) are not posted again; suggestions for
-              # findings that are gone are deleted. GitHub sets line to null on comments
-              # it could not carry to the new revision, so those are deleted too.
+              # One suggested change per finding with a fix, kept in sync with the
+              # findings; see dev/sync-review-comments.sh
               if: github.event.pull_request.head.repo.full_name == github.repository
               env:
                   GH_TOKEN: ${{ github.token }}
                   PR_NUMBER: ${{ github.event.pull_request.number }}
-              run: |
-                  key='(.path + ":" + (.line | tostring) + ":" + (.body | split("\n")[0]))'
-                  gh api "repos/$GITHUB_REPOSITORY/pulls/$PR_NUMBER/comments" --paginate \
-                      --jq ".[] | select(.body | startswith(\"<!-- check-links-finding:\")) | {id, key: $key}" \
-                      | jq -s . > "$RUNNER_TEMP/posted.json"
-                  jq --slurpfile posted "$RUNNER_TEMP/posted.json" \
-                      ".comments |= map(select($key as \$key | \$posted[0] | any(.key == \$key) | not))" \
-                      "$RUNNER_TEMP/review.json" > "$RUNNER_TEMP/review-new.json"
-
-                  jq -r --slurpfile review "$RUNNER_TEMP/review.json" \
-                      ".[] | select(.key as \$key | \$review[0].comments | any($key == \$key) | not) | .id" \
-                      "$RUNNER_TEMP/posted.json" | while read -r comment_id; do
-                      gh api --method DELETE "repos/$GITHUB_REPOSITORY/pulls/comments/$comment_id"
-                  done
-
-                  if [ "$(jq '.comments | length' "$RUNNER_TEMP/review-new.json")" -gt 0 ]; then
-                      gh api --method POST "repos/$GITHUB_REPOSITORY/pulls/$PR_NUMBER/reviews" \
-                          --input "$RUNNER_TEMP/review-new.json" > /dev/null \
-                          || echo "::warning::Could not post the suggested fixes; they are in the report above"
-                  fi
+              run: dev/sync-review-comments.sh '<!-- check-links-finding:' "$RUNNER_TEMP/review.json"
 
             - name: Fail when this PR introduces broken links
               if: steps.check.outputs.broken == 'true'

dev/sync-review-comments.sh

@@ -0,0 +1,40 @@
+#!/usr/bin/env sh
+# Make a check's suggested-change review comments on a PR match a review.json
+# ({comments: [{path, line, start_line?, body}]}): post the new ones, update
+# the ones whose text changed, and delete the ones whose finding is gone.
+# GitHub sets line to null on comments it could not carry to the new revision,
+# so those are deleted too. Comments are matched by file, line, and the
+# marker comment on their first line, e.g. "<!-- check-links-finding: <url> -->".
+#
+# Usage: dev/sync-review-comments.sh '<!-- check-links-finding:' review.json
+# Needs GH_TOKEN, GITHUB_REPOSITORY, and PR_NUMBER.
+set -eu
+marker=$1
+review=$2
+key='(.path + ":" + (.line | tostring) + ":" + (.body | split("\n")[0]))'
+pulls="repos/$GITHUB_REPOSITORY/pulls"
+
+posted=$(gh api "$pulls/$PR_NUMBER/comments" --paginate \
+    --jq ".[] | select(.body | startswith(\"$marker\")) | {id, body, key: $key}" | jq -s .)
+
+printf '%s' "$posted" | jq -c --slurpfile review "$review" ".[]
+    | .key as \$key
+    | (\$review[0].comments | map(select($key == \$key)) | first) as \$wanted
+    | if \$wanted == null then {id, method: \"DELETE\"}
+      elif \$wanted.body != .body then {id, method: \"PATCH\", body: \$wanted.body}
+      else empty end" \
+| while read -r change; do
+    comment="$pulls/comments/$(printf '%s' "$change" | jq -r .id)"
+    if [ "$(printf '%s' "$change" | jq -r .method)" = DELETE ]; then
+        gh api --method DELETE "$comment" < /dev/null
+    else
+        printf '%s' "$change" | jq '{body}' | gh api --method PATCH "$comment" --input - > /dev/null
+    fi
+done
+
+fresh=$(jq --argjson posted "$posted" \
+    ".comments |= map(select($key as \$key | \$posted | any(.key == \$key) | not))" "$review")
+if [ "$(printf '%s' "$fresh" | jq '.comments | length')" -gt 0 ]; then
+    printf '%s' "$fresh" | gh api --method POST "$pulls/$PR_NUMBER/reviews" --input - > /dev/null \
+        || echo "::warning::Could not post the suggested fixes; they are in the report above"
+fi