fix(action): better logging

Be more clear about why it failed

action.yml

@@ -66,6 +66,8 @@ runs:
         HEAD_BRANCH: ${{ inputs.base-branch }}
         JOB_NAME: ${{ inputs.job-name }}
       run: |
+        . "${GITHUB_ACTION_PATH}/utils.sh"
+
         # USAGE: base_report_url
         base_report_url() {
           curl -X 'GET' \
@@ -77,27 +79,33 @@ runs:
                 --arg head_branch "$HEAD_BRANCH" \
                 '[.workflow_runs[] | select(.name == $name and .head_branch == $head_branch)] | first | .url'
         }
-        # USAGE: has_report <RUN_URL>
+        # USAGE: has_report <REPORT_URL>
         has_report() {
           http_code=$(curl -X 'GET' -o /dev/null --silent -Iw '%{http_code}' \
             -H "Authorization: token $GITHUB_TOKEN" \
-            "$1/artifacts/$ARTIFACT_NAME")
+            "$1")
+          log "Got code $http_code for $url"
           test "$http_code" = '200'
         }
 
         # If we have a previous report compare against it
         if [ "$JOB_NAME" ] && [ "$HEAD_BRANCH" ]; then
           url=$(base_report_url)
-          echo "Found previous run at: $url"
-          if has_report "$url"; then
+          log "Found previous run at: $url"
+          report_url="$url/artifacts/$ARTIFACT_NAME"
+          if has_report "$report_url"; then
+            log 'Found previous report, downloading...'
             curl -X 'GET' \
               -H "Authorization: token $GITHUB_TOKEN" \
               "$url/artifacts/$ARTIFACT_NAME" |
               gunzip > old-report.json
-            echo 'Found previous report'
+            log "Reporting on sizes and comparing to sizes in $HEAD_BRANCH"
             "$GITHUB_ACTION_PATH/comment_on_pr.sh" report.json old-report.json
             exit 0
+          else
+            log "Failed to find previous report, expected at: $report_url"
           fi
         fi
 
+        log 'Reporting on sizes'
         "$GITHUB_ACTION_PATH/comment_on_pr.sh" report.json