Adding helper for quickly fixing goldens (#6203)

![](https://media.giphy.com/media/zAL9cDnKmFQIAUGQS4/giphy.gif)

https://github.com/flutter/devtools/assets/1386322/1072bead-b025-46c0-b3d4-423339cfb1b8

.github/workflows/build.yaml

@@ -101,6 +101,12 @@ jobs:
         with:
           name: golden_image_failures.${{ matrix.bot }}
           path: packages/devtools_app/test/**/failures/*.png
+      - name: Notify of Quick Fix
+        if: failure()
+        env:
+          WORKFLOW_ID: ${{ github.run_id }}
+        run: |
+          echo "::notice title=To Quickly Fix Goldens:: Run \`./tool/fix_goldens.sh $WORKFLOW_ID\` on your local branch."
 
   integration-test:
     name: integration-test ${{ matrix.bot }} - ${{ matrix.device }}

tool/fix_goldens.sh

@@ -0,0 +1,65 @@
+#!/bin/bash -e
+RUN_ID=$1
+
+SCRIPT_DIR=$( cd -- "$( dirname -- "${BASH_SOURCE[0]}" )" &> /dev/null && pwd )
+cd "$SCRIPT_DIR/.."
+
+help()
+{
+   # Display Help
+   >&2 echo "A helper script for downloading and applying golden fixes, when they are broken."
+   >&2 echo
+   >&2 echo "Syntax: fix_goldens.sh RUN_ID"
+   >&2 echo "RUN_ID     The ID of the workflow run where the goldens are failing"
+   >&2 echo
+}
+
+if [ $# -gt 1 ]
+  then
+    >&2 echo "ERROR: $0 takes only 1 argument"
+    help
+    exit 1
+fi
+
+if [ -z "$1" ]
+  then
+    >&2 echo "ERROR: Expected a RUN_ID"
+    help
+    exit 1
+fi
+
+DOWNLOAD_DIR=$(mktemp -d)
+
+echo "Downloading the artifacts to $DOWNLOAD_DIR"
+gh run download $RUN_ID -p "*golden_image_failures*" -D "$DOWNLOAD_DIR"
+
+NEW_GOLDENS=$(find $DOWNLOAD_DIR -type f | grep "testImage.png" )
+
+cd packages/devtools_app/test/
+
+while IFS= read -r GOLDEN ; do
+  FILE_NAME=$(basename $GOLDEN | sed "s|_testImage.png$|.png|")
+  FOUND_FILES=$(find . -name "$FILE_NAME" )
+  FOUND_FILE_COUNT=$(echo -n "$FOUND_FILES" | grep -c '^')
+
+  if [[ $FOUND_FILE_COUNT -ne 1 ]] ; then
+    # If there are goldens with conflicting names, we need to pick which one
+    # maps to the artifact.
+    echo "Multiple goldens found for $(echo $GOLDEN| sed 's|^.*golden_image_failures[^/]*/||')"
+    echo "Select which golden should be overridden:"
+
+    select SELECTED_FILE in $FOUND_FILES
+    do
+      DEST_PATH="$SELECTED_FILE"
+      break;
+    done </dev/tty
+  else
+    DEST_PATH=$FOUND_FILES
+  fi
+
+  echo "FIXED: $DEST_PATH"
+  mv "$GOLDEN" "$DEST_PATH"
+done <<< "$NEW_GOLDENS"
+
+echo "Done updating $(echo -n "$NEW_GOLDENS" | grep -c '^') goldens"
+