Expand spec coverage and refactor the `Account.find_` methods (#3485)

* Move specs for account finder methods to concern spec

* Move account finder methods to concern

* Improve spec wording

* Use more explicit comparison to ensure correct return value

* Add coverage for .find_local! and .find_remote!

* Add some methods to the finder

* Use arel on matching_username method

* Avoid ternary in matching domain method

* Simplify finder methods

* Use an AccountFinder class to simplify lookup

2 files changed, 93 insertions, 48 deletions

diff --git a/spec/models/account_spec.rb b/spec/models/account_spec.rb
index 08098854b..ebec463e1 100644
--- a/spec/models/account_spec.rb
+++ b/spec/models/account_spec.rb
@@ -301,54 +301,6 @@ RSpec.describe Account, type: :model do
     end
   end
 
-  describe '.find_local' do
-    before do
-      Fabricate(:account, username: 'Alice')
-    end
-
-    it 'returns Alice for alice' do
-      expect(Account.find_local('alice')).to_not be_nil
-    end
-
-    it 'returns Alice for Alice' do
-      expect(Account.find_local('Alice')).to_not be_nil
-    end
-
-    it 'does not return anything for a_ice' do
-      expect(Account.find_local('a_ice')).to be_nil
-    end
-
-    it 'does not return anything for al%' do
-      expect(Account.find_local('al%')).to be_nil
-    end
-  end
-
-  describe '.find_remote' do
-    before do
-      Fabricate(:account, username: 'Alice', domain: 'mastodon.social')
-    end
-
-    it 'returns Alice for alice@mastodon.social' do
-      expect(Account.find_remote('alice', 'mastodon.social')).to_not be_nil
-    end
-
-    it 'returns Alice for ALICE@MASTODON.SOCIAL' do
-      expect(Account.find_remote('ALICE', 'MASTODON.SOCIAL')).to_not be_nil
-    end
-
-    it 'does not return anything for a_ice@mastodon.social' do
-      expect(Account.find_remote('a_ice', 'mastodon.social')).to be_nil
-    end
-
-    it 'does not return anything for alice@m_stodon.social' do
-      expect(Account.find_remote('alice', 'm_stodon.social')).to be_nil
-    end
-
-    it 'does not return anything for alice@m%' do
-      expect(Account.find_remote('alice', 'm%')).to be_nil
-    end
-  end
-
   describe '.following_map' do
     it 'returns an hash' do
       expect(Account.following_map([], 1)).to be_a Hash
diff --git a/spec/models/concerns/account_finder_concern_spec.rb b/spec/models/concerns/account_finder_concern_spec.rb
new file mode 100644
index 000000000..05f0f44f2
--- /dev/null
+++ b/spec/models/concerns/account_finder_concern_spec.rb
@@ -0,0 +1,93 @@
+# frozen_string_literal: true
+
+require 'rails_helper'
+
+describe AccountFinderConcern do
+  describe 'local finders' do
+    before do
+      @account = Fabricate(:account, username: 'Alice')
+    end
+
+    describe '.find_local' do
+      it 'returns case-insensitive result' do
+        expect(Account.find_local('alice')).to eq(@account)
+      end
+
+      it 'returns correctly cased result' do
+        expect(Account.find_local('Alice')).to eq(@account)
+      end
+
+      it 'returns nil without a match' do
+        expect(Account.find_local('a_ice')).to be_nil
+      end
+
+      it 'returns nil for regex style username value' do
+        expect(Account.find_local('al%')).to be_nil
+      end
+    end
+
+    describe '.find_local!' do
+      it 'returns matching result' do
+        expect(Account.find_local!('alice')).to eq(@account)
+      end
+
+      it 'raises on non-matching result' do
+        expect { Account.find_local!('missing') }.to raise_error(ActiveRecord::RecordNotFound)
+      end
+
+      it 'raises with blank username' do
+        expect { Account.find_local!('') }.to raise_error(ActiveRecord::RecordNotFound)
+      end
+
+      it 'raises with nil username' do
+        expect { Account.find_local!(nil) }.to raise_error(ActiveRecord::RecordNotFound)
+      end
+    end
+  end
+
+  describe 'remote finders' do
+    before do
+      @account = Fabricate(:account, username: 'Alice', domain: 'mastodon.social')
+    end
+
+    describe '.find_remote' do
+      it 'returns exact match result' do
+        expect(Account.find_remote('alice', 'mastodon.social')).to eq(@account)
+      end
+
+      it 'returns case-insensitive result' do
+        expect(Account.find_remote('ALICE', 'MASTODON.SOCIAL')).to eq(@account)
+      end
+
+      it 'returns nil when username does not match' do
+        expect(Account.find_remote('a_ice', 'mastodon.social')).to be_nil
+      end
+
+      it 'returns nil when domain does not match' do
+        expect(Account.find_remote('alice', 'm_stodon.social')).to be_nil
+      end
+
+      it 'returns nil for regex style domain value' do
+        expect(Account.find_remote('alice', 'm%')).to be_nil
+      end
+    end
+
+    describe '.find_remote!' do
+      it 'returns matching result' do
+        expect(Account.find_remote!('alice', 'mastodon.social')).to eq(@account)
+      end
+
+      it 'raises on non-matching result' do
+        expect { Account.find_remote!('missing', 'mastodon.host') }.to raise_error(ActiveRecord::RecordNotFound)
+      end
+
+      it 'raises with blank username' do
+        expect { Account.find_remote!('', '') }.to raise_error(ActiveRecord::RecordNotFound)
+      end
+
+      it 'raises with nil username' do
+        expect { Account.find_remote!(nil, nil) }.to raise_error(ActiveRecord::RecordNotFound)
+      end
+    end
+  end
+end