1 files changed, 62 insertions, 0 deletions
diff --git a/spec/rubocop/cop/active_model_errors_direct_manipulation_spec.rb b/spec/rubocop/cop/active_model_errors_direct_manipulation_spec.rb
new file mode 100644
index 00000000000..37fcdb38907
--- /dev/null
+++ b/spec/rubocop/cop/active_model_errors_direct_manipulation_spec.rb
@@ -0,0 +1,62 @@
+# frozen_string_literal: true
+
+require 'fast_spec_helper'
+require_relative '../../../rubocop/cop/active_model_errors_direct_manipulation'
+
+RSpec.describe RuboCop::Cop::ActiveModelErrorsDirectManipulation do
+  subject(:cop) { described_class.new }
+
+  context 'when modifying errors' do
+    it 'registers an offense' do
+      expect_offense(<<~PATTERN)
+        user.errors[:name] << 'msg'
+        ^^^^^^^^^^^^^^^^^^^^^^^^^^^ Avoid manipulating errors hash directly. [...]
+      PATTERN
+    end
+
+    context 'when assigning' do
+      it 'registers an offense' do
+        expect_offense(<<~PATTERN)
+        user.errors[:name] = []
+        ^^^^^^^^^^^^^^^^^^^^^^^ Avoid manipulating errors hash directly. [...]
+        PATTERN
+      end
+    end
+  end
+
+  context 'when modifying errors.messages' do
+    it 'registers an offense' do
+      expect_offense(<<~PATTERN)
+        user.errors.messages[:name] << 'msg'
+        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Avoid manipulating errors hash directly. [...]
+      PATTERN
+    end
+
+    context 'when assigning' do
+      it 'registers an offense' do
+        expect_offense(<<~PATTERN)
+        user.errors.messages[:name] = []
+        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Avoid manipulating errors hash directly. [...]
+        PATTERN
+      end
+    end
+  end
+
+  context 'when modifying errors.details' do
+    it 'registers an offense' do
+      expect_offense(<<~PATTERN)
+        user.errors.details[:name] << {}
+        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Avoid manipulating errors hash directly. [...]
+      PATTERN
+    end
+
+    context 'when assigning' do
+      it 'registers an offense' do
+        expect_offense(<<~PATTERN)
+        user.errors.details[:name] = []
+        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Avoid manipulating errors hash directly. [...]
+        PATTERN
+      end
+    end
+  end
+end