build: restore linter stuff

Author: es3n1n

.eslintignore

@@ -0,0 +1,27 @@
+# Include dotfiles
+!.*
+
+# Re-add default ignore patterns
+node_modules/
+**/node_modules/**
+**/node_modules/**/*.mjs
+**/node_modules/**/*.js
+.git/
+
+# Ignore yarn 2 stuff
+.yarn/
+
+# Ignore build folders
+dist
+
+# Ignore coverage reports
+coverage/
+
+# Ignore built docs
+/docs/site
+
+# Duplicate api-types ignore rules here because otherwise their paths get
+# broken when eslint is run from the monorepo root
+/packages/api-types/*.js
+/packages/api-types/*.mjs
+/packages/api-types/*.d.ts

lint-staged.config.js

@@ -0,0 +1,22 @@
+const { CLIEngine } = require('eslint')
+
+const cli = new CLIEngine({})
+
+const tsPackages = ['packages/server/', 'packages/client/']
+
+const extractPackage = file => /packages\/.*?\//.exec(file)?.[0]
+
+module.exports = {
+  '*.{j,t}s?(x)': files =>
+    [
+      'eslint --max-warnings=0 --fix ' +
+        files.filter(file => !cli.isPathIgnored(file)).join(' '),
+      'jest --ci --forceExit --findRelatedTests ' + files.join(' '),
+    ].filter(Boolean),
+  'packages/*/**/*.ts?(x)': files =>
+    Array.from(new Set(files.map(extractPackage)))
+      .filter(packageDir => tsPackages.includes(packageDir))
+      .map(packageDir => `tsc -b ${packageDir}`),
+  '*.({j,t}s?(x)|md?(x)|json|y?(a)ml)': 'prettier --write',
+  'yarn.lock': () => 'yarn dedupe',
+}