From dcea9ab42709b776ea5f9cdb3dc3a0aff6fc9f8f Mon Sep 17 00:00:00 2001
From: Joe Hanley <joehanley@google.com>
Date: Fri, 13 Feb 2026 15:39:38 -0800
Subject: [PATCH] Cache lint results for unchanged files

---
 .github/workflows/node-test.yml | 8 ++++++++
 .gitignore                      | 1 +
 package.json                    | 4 ++--
 3 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/.github/workflows/node-test.yml b/.github/workflows/node-test.yml
index 9e3e258232b..7616568c336 100644
--- a/.github/workflows/node-test.yml
+++ b/.github/workflows/node-test.yml
@@ -163,6 +163,14 @@ jobs:
           cache: npm
           cache-dependency-path: npm-shrinkwrap.json
 
+      - name: Cache ESLint
+        uses: actions/cache@v3
+        with:
+          path: .eslintcache
+          key: eslint-${{ runner.os }}-node${{ matrix.node-version }}-${{ hashFiles('**/*.ts', '**/*.js') }}
+          restore-keys: |
+            eslint-${{ runner.os }}-node${{ matrix.node-version }}-
+
       - run: npm i -g npm@9.5
       - run: npm ci
       - run: npm test -- -- --forbid-only
diff --git a/.gitignore b/.gitignore
index 88fd05c2e9f..d84c7bbac09 100644
--- a/.gitignore
+++ b/.gitignore
@@ -20,6 +20,7 @@ test_output.log
 scripts/emulator-tests/functions/index.js
 yarn.lock
 .npmrc
+.eslintcache
 
 .DS_Store
 .idea
diff --git a/package.json b/package.json
index 70ed901e04a..f2ccd500f0d 100644
--- a/package.json
+++ b/package.json
@@ -21,8 +21,8 @@
     "lint": "npm run lint:ts && npm run lint:other",
     "lint:changed-files": "ts-node ./scripts/lint-changed-files.ts",
     "lint:other": "prettier --check '**/*.{md,yaml,yml}'",
-    "lint:quiet": "npm run lint:ts -- --quiet && npm run lint:other",
-    "lint:ts": "eslint --config .eslintrc.js --ext .ts,.js .",
+    "lint:quiet": "npm run lint:ts -- --cache --quiet && npm run lint:other",
+    "lint:ts": "eslint --cache --config .eslintrc.js --ext .ts,.js .",
     "mocha:fast": "mocha 'src/**/*.spec.{ts,js}'",
     "mocha": "nyc --reporter=html mocha 'src/**/*.spec.{ts,js}'",
     "prepare": "npm run clean && npm run build:publish",