Raise errors to top of report

run-scalafmt.sh

@@ -29,8 +29,38 @@ report() {
     echo
 }
 
+errors=$(mktemp)
+
+if grep -q '^error:' "$warnings"; then
+  warnings="$warnings" errors="$errors" perl -e '
+    my $new_warnings = "$ENV{warnings}.new";
+    open my $warnings_in, "<", $ENV{warnings};
+    open my $warnings_out, ">", $new_warnings;
+    open my $errors, ">", $ENV{errors};
+    my $found_error=0;
+    while (<$warnings_in>) {
+      if ($found_error) {
+        print $errors $_;
+      } elsif (/^error:/) {
+        $found_error=1;
+        print $errors $_;
+      } else {
+        print $warnings_out $_;
+      }
+    }
+    close $warnings_in;
+    close $warnings_out;
+    close $errors;
+    rename new_warnings, $ENV{warnings};
+  '
+fi
+
 (
     echo "# scalafmt failed ($result)"
+    if [ -s "$errors" ]; then
+      echo '# Errors'
+      cat "$errors"
+    fi
     report "$output" "Output"
     report "$warnings" "Warnings"
 ) >> "$GITHUB_STEP_SUMMARY"