From de4e4c57251b95ff9884665db993c0bc27e27c87 Mon Sep 17 00:00:00 2001
From: Ted Johansson <drenmi@gmail.com>
Date: Tue, 17 Jan 2017 00:58:48 +0800
Subject: [PATCH] [Fix #3918] Prevent `Rails/EnumUniqueness` from breaking on a
 non-literal hash value

This cop would break on any enum hash that did not have a literal value.
This change fixes that.
---
 CHANGELOG.md                                  |  1 +
 lib/rubocop/cop/rails/enum_uniqueness.rb      |  2 +-
 .../rubocop/cop/rails/enum_uniqueness_spec.rb | 28 ++++++++++++++++++-
 3 files changed, 29 insertions(+), 2 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index dc58c1822392..65c612dccaf1 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,6 +6,7 @@
 
 * [#3911](https://github.com/bbatsov/rubocop/issues/3911): Prevent a crash in `Performance/RegexpMatch` cop with module definition. ([@pocke][])
 * [#3908](https://github.com/bbatsov/rubocop/issues/3908): Prevent `Style/AlignHash` from breaking on a keyword splat when using enforced `table` style. ([@drenmi][])
+* [#3918](https://github.com/bbatsov/rubocop/issues/3918): Prevent `Rails/EnumUniqueness` from breaking on a non-literal hash value. ([@drenmi][])
 
 ## 0.47.0 (2017-01-16)
 
diff --git a/lib/rubocop/cop/rails/enum_uniqueness.rb b/lib/rubocop/cop/rails/enum_uniqueness.rb
index c1f906d78cfa..768606e225fa 100644
--- a/lib/rubocop/cop/rails/enum_uniqueness.rb
+++ b/lib/rubocop/cop/rails/enum_uniqueness.rb
@@ -23,7 +23,7 @@ class EnumUniqueness < Cop
         MSG = 'Duplicate value `%s` found in `%s` enum declaration.'.freeze
 
         def_node_matcher :enum_declaration, <<-END
-          (send nil :enum (hash (pair (_ $_) $_)))
+          (send nil :enum (hash (pair (_ $_) ${array hash})))
         END
 
         def on_send(node)
diff --git a/spec/rubocop/cop/rails/enum_uniqueness_spec.rb b/spec/rubocop/cop/rails/enum_uniqueness_spec.rb
index f3c0258f8da2..1af9f3ac8ef7 100644
--- a/spec/rubocop/cop/rails/enum_uniqueness_spec.rb
+++ b/spec/rubocop/cop/rails/enum_uniqueness_spec.rb
@@ -64,11 +64,37 @@
   end
 
   context 'when receiving a variable' do
-    it 'does not register an offence' do
+    it 'does not register an offense' do
       inspect_source(cop, ['var = { status: { active: 0, archived: 1 } }',
                            'enum var'])
 
       expect(cop.offenses).to be_empty
     end
   end
+
+  context 'when receiving a hash without literal values' do
+    context 'when value is a variable' do
+      it 'does not register an offense' do
+        inspect_source(cop, 'enum status: statuses')
+
+        expect(cop.offenses).to be_empty
+      end
+    end
+
+    context 'when value is a method chain' do
+      it 'does not register an offense' do
+        inspect_source(cop, 'enum status: User.statuses.keys')
+
+        expect(cop.offenses).to be_empty
+      end
+    end
+
+    context 'when value is a constant' do
+      it 'does not register an offense' do
+        inspect_source(cop, 'enum status: STATUSES')
+
+        expect(cop.offenses).to be_empty
+      end
+    end
+  end
 end