DEV: Rename direct message related models

This is a followup of the previous refactor where we created two new
models to handle all the dedicated logic that was present in the
`ChatChannel` model.

For the sake of consistency, `DMChannel` has been renamed to
`DirectMessageChannel` and the previous `DirectMessageChannel` model is
now named `DirectMessage`. This should help reasoning about direct
messages.

plugins/chat/spec/models/d_m_channel_spec.rb

@@ -1,66 +0,0 @@
-# frozen_string_literal: true
-
-RSpec.describe DMChannel do
-  subject(:channel) { Fabricate.build(:dm_channel) }
-
-  it_behaves_like "a chat channel model"
-
-  it { is_expected.to delegate_method(:allowed_user_ids).to(:direct_message_channel).as(:user_ids) }
-
-  describe "#category_channel?" do
-    it "always returns false" do
-      expect(channel).not_to be_a_category_channel
-    end
-  end
-
-  describe "#public_channel?" do
-    it "always returns false" do
-      expect(channel).not_to be_a_public_channel
-    end
-  end
-
-  describe "#chatable_has_custom_fields?" do
-    it "always returns false" do
-      expect(channel).not_to be_a_chatable_has_custom_fields
-    end
-  end
-
-  describe "#direct_message_channel?" do
-    it "always returns true" do
-      expect(channel).to be_a_direct_message_channel
-    end
-  end
-
-  describe "#read_restricted?" do
-    it "always returns true" do
-      expect(channel).to be_read_restricted
-    end
-  end
-
-  describe "#allowed_group_ids" do
-    it "always returns nothing" do
-      expect(channel.allowed_group_ids).to be_nil
-    end
-  end
-
-  describe "#chatable_url" do
-    it "always returns nothing" do
-      expect(channel.chatable_url).to be_nil
-    end
-  end
-
-  describe "#title" do
-    subject(:title) { channel.title(user) }
-
-    let(:user) { stub }
-    let(:direct_message_channel) { channel.direct_message_channel }
-
-    it "delegates to direct_message_channel" do
-      direct_message_channel
-        .expects(:chat_channel_title_for_user)
-        .with(channel, user)
-        .returns("something")
-      expect(title).to eq("something")
-    end
-  end
-end

plugins/chat/spec/models/direct_message_channel_spec.rb

@@ -1,73 +1,63 @@
 # frozen_string_literal: true
 
-require "rails_helper"
+RSpec.describe DirectMessageChannel do
+  subject(:channel) { Fabricate.build(:direct_message_channel) }
 
-describe DirectMessageChannel do
-  fab!(:user1) { Fabricate(:user, username: "chatdmfellow1") }
-  fab!(:user2) { Fabricate(:user, username: "chatdmuser") }
-  fab!(:chat_channel) { Fabricate(:chat_channel) }
+  it_behaves_like "a chat channel model"
 
-  it_behaves_like "a chatable model" do
-    fab!(:chatable) { Fabricate(:direct_message_channel) }
-    let(:channel_class) { DMChannel }
+  it { is_expected.to delegate_method(:allowed_user_ids).to(:direct_message).as(:user_ids) }
+
+  describe "#category_channel?" do
+    it "always returns false" do
+      expect(channel).not_to be_a_category_channel
+    end
   end
 
-  describe "#chat_channel_title_for_user" do
-    it "returns a nicely formatted name if it's more than one user" do
-      user3 = Fabricate.build(:user, username: "chatdmregent")
-      direct_message_channel = Fabricate(:direct_message_channel, users: [user1, user2, user3])
-
-      expect(direct_message_channel.chat_channel_title_for_user(chat_channel, user1)).to eq(
-        I18n.t(
-          "chat.channel.dm_title.multi_user",
-          users: [user3, user2].map { |u| "@#{u.username}" }.join(", "),
-        ),
-      )
+  describe "#public_channel?" do
+    it "always returns false" do
+      expect(channel).not_to be_a_public_channel
     end
+  end
 
-    it "returns a nicely formatted truncated name if it's more than 5 users" do
-      user3 = Fabricate.build(:user, username: "chatdmregent")
-
-      users = [user1, user2, user3].concat(
-        5.times.map.with_index { |i| Fabricate(:user, username: "chatdmuser#{i}") },
-      )
-      direct_message_channel = Fabricate(:direct_message_channel, users: users)
-
-      expect(direct_message_channel.chat_channel_title_for_user(chat_channel, user1)).to eq(
-        I18n.t(
-          "chat.channel.dm_title.multi_user_truncated",
-          users: users[1..5].sort_by(&:username).map { |u| "@#{u.username}" }.join(", "),
-          leftover: 2,
-        ),
-      )
+  describe "#chatable_has_custom_fields?" do
+    it "always returns false" do
+      expect(channel).not_to be_a_chatable_has_custom_fields
     end
+  end
 
-    it "returns the other user's username if it's a dm to that user" do
-      direct_message_channel = Fabricate(:direct_message_channel, users: [user1, user2])
-
-      expect(direct_message_channel.chat_channel_title_for_user(chat_channel, user1)).to eq(
-        I18n.t("chat.channel.dm_title.single_user", user: "@#{user2.username}"),
-      )
+  describe "#direct_message_channel?" do
+    it "always returns true" do
+      expect(channel).to be_a_direct_message_channel
     end
+  end
 
-    it "returns the current user's username if it's a dm to self" do
-      direct_message_channel = Fabricate(:direct_message_channel, users: [user1])
-
-      expect(direct_message_channel.chat_channel_title_for_user(chat_channel, user1)).to eq(
-        I18n.t("chat.channel.dm_title.single_user", user: "@#{user1.username}"),
-      )
+  describe "#read_restricted?" do
+    it "always returns true" do
+      expect(channel).to be_read_restricted
     end
+  end
 
-    context "when user is deleted" do
-      it "returns a placeholder username" do
-        direct_message_channel = Fabricate(:direct_message_channel, users: [user1, user2])
-        user2.destroy!
-        direct_message_channel.reload
+  describe "#allowed_group_ids" do
+    it "always returns nothing" do
+      expect(channel.allowed_group_ids).to be_nil
+    end
+  end
 
-        expect(direct_message_channel.chat_channel_title_for_user(chat_channel, user1)).to eq(
-          "@#{I18n.t("chat.deleted_chat_username")}",
-        )
-      end
+  describe "#chatable_url" do
+    it "always returns nothing" do
+      expect(channel.chatable_url).to be_nil
+    end
+  end
+
+  describe "#title" do
+    subject(:title) { channel.title(user) }
+
+    let(:user) { stub }
+    let(:direct_message) { channel.direct_message }
+
+    it "delegates to direct_message" do
+      direct_message.expects(:chat_channel_title_for_user).with(channel, user).returns("something")
+      expect(title).to eq("something")
     end
   end
 end

plugins/chat/spec/models/direct_message_spec.rb

@@ -0,0 +1,73 @@
+# frozen_string_literal: true
+
+require "rails_helper"
+
+describe DirectMessage do
+  fab!(:user1) { Fabricate(:user, username: "chatdmfellow1") }
+  fab!(:user2) { Fabricate(:user, username: "chatdmuser") }
+  fab!(:chat_channel) { Fabricate(:direct_message_channel) }
+
+  it_behaves_like "a chatable model" do
+    fab!(:chatable) { Fabricate(:direct_message) }
+    let(:channel_class) { DirectMessageChannel }
+  end
+
+  describe "#chat_channel_title_for_user" do
+    it "returns a nicely formatted name if it's more than one user" do
+      user3 = Fabricate.build(:user, username: "chatdmregent")
+      direct_message = Fabricate(:direct_message, users: [user1, user2, user3])
+
+      expect(direct_message.chat_channel_title_for_user(chat_channel, user1)).to eq(
+        I18n.t(
+          "chat.channel.dm_title.multi_user",
+          users: [user3, user2].map { |u| "@#{u.username}" }.join(", "),
+        ),
+      )
+    end
+
+    it "returns a nicely formatted truncated name if it's more than 5 users" do
+      user3 = Fabricate.build(:user, username: "chatdmregent")
+
+      users = [user1, user2, user3].concat(
+        5.times.map.with_index { |i| Fabricate(:user, username: "chatdmuser#{i}") },
+      )
+      direct_message = Fabricate(:direct_message, users: users)
+
+      expect(direct_message.chat_channel_title_for_user(chat_channel, user1)).to eq(
+        I18n.t(
+          "chat.channel.dm_title.multi_user_truncated",
+          users: users[1..5].sort_by(&:username).map { |u| "@#{u.username}" }.join(", "),
+          leftover: 2,
+        ),
+      )
+    end
+
+    it "returns the other user's username if it's a dm to that user" do
+      direct_message = Fabricate(:direct_message, users: [user1, user2])
+
+      expect(direct_message.chat_channel_title_for_user(chat_channel, user1)).to eq(
+        I18n.t("chat.channel.dm_title.single_user", user: "@#{user2.username}"),
+      )
+    end
+
+    it "returns the current user's username if it's a dm to self" do
+      direct_message = Fabricate(:direct_message, users: [user1])
+
+      expect(direct_message.chat_channel_title_for_user(chat_channel, user1)).to eq(
+        I18n.t("chat.channel.dm_title.single_user", user: "@#{user1.username}"),
+      )
+    end
+
+    context "when user is deleted" do
+      it "returns a placeholder username" do
+        direct_message = Fabricate(:direct_message, users: [user1, user2])
+        user2.destroy!
+        direct_message.reload
+
+        expect(direct_message.chat_channel_title_for_user(chat_channel, user1)).to eq(
+          "@#{I18n.t("chat.deleted_chat_username")}",
+        )
+      end
+    end
+  end
+end