Split out Rubocop into a dedicated job and only run once

Exclude both the "bundle" and "tmp" directory.  The former ensures we don't run rubocop against installed gems.  The latter ensures we don't run it against generated code and apps locally.

Author: petergoldstein

.github/workflows/ci.yml

@@ -9,6 +9,19 @@ on:
     branches:
       - '*'
 jobs:
+  rubocop:
+    name: Rubocop
+    runs-on: 'ubuntu-20.04'
+    steps:
+      - uses: actions/checkout@v2
+      - uses: ruby/setup-ruby@v1
+        with:
+          ruby-version: '3.0'
+      - run: script/update_rubygems_and_install_bundler
+      - run: bundle install --standalone
+      - run: bundle binstubs --all
+      - run: script/run_rubocop
+
   test:
     name: 'Ruby: ${{ matrix.ruby }}, Rails: ${{ matrix.env.RAILS_VERSION }}'
     runs-on: ubuntu-20.04

.rubocop.yml

@@ -5,7 +5,9 @@ AllCops:
   Exclude:
     # Templates are really ERB which Rubocop does not parse
     - bin/**/*
+    - bundle/**/*
     - lib/generators/rspec/*/templates/**/*
+    - tmp/**/*
 
 Bundler/DuplicatedGem:
   Enabled: false

script/predicate_functions.sh

@@ -97,11 +97,3 @@ function documentation_enforced {
     return 1
   fi
 }
-
-function style_and_lint_enforced {
- if [ -x ./bin/rubocop ]; then
-   return 0
- else
-   return 1
- fi
-}

script/run_build

@@ -26,10 +26,6 @@ if documentation_enforced; then
   fold "doc check" check_documentation_coverage
 fi
 
-if style_and_lint_enforced; then
-  fold "rubocop" check_style_and_lint
-fi
-
 if is_mri; then
   fold "one-by-one specs" run_specs_one_by_one
   run_all_spec_suites

script/run_rubocop

@@ -0,0 +1,14 @@
+#!/bin/bash
+# This file was generated on 2022-01-10T22:24:10+00:00 from the rspec-dev repo.
+# DO NOT modify it by hand as your changes will get lost the next time it is generated.
+
+set -e
+source script/functions.sh
+
+# Allow repos to override the default functions and add their own
+if [ -f script/custom_build_functions.sh ]; then
+  source script/custom_build_functions.sh
+fi
+
+
+fold "rubocop" check_style_and_lint