DEV: Move discourse-chat to the core repo. (#18776)

As part of this move, we are also renaming `discourse-chat` to `chat`.

plugins/chat/spec/components/chat_seeder_spec.rb

@@ -0,0 +1,72 @@
+# frozen_string_literal: true
+
+require "rails_helper"
+
+describe ChatSeeder do
+  fab!(:staff_category) { Fabricate(:private_category, name: "Staff", group: Group[:staff]) }
+  fab!(:general_category) { Fabricate(:category, name: "General") }
+
+  fab!(:staff_user1) do
+    Fabricate(:user, last_seen_at: 1.minute.ago, groups: [Group[:staff], Group[:everyone]])
+  end
+  fab!(:staff_user2) do
+    Fabricate(:user, last_seen_at: 1.minute.ago, groups: [Group[:staff], Group[:everyone]])
+  end
+
+  fab!(:regular_user) { Fabricate(:user, last_seen_at: 1.minute.ago, groups: [Group[:everyone]]) }
+
+  before do
+    SiteSetting.staff_category_id = staff_category.id
+    SiteSetting.general_category_id = general_category.id
+    Jobs.run_immediately!
+  end
+
+  def assert_channel_was_correctly_seeded(channel, group)
+    expect(channel).to be_present
+    expect(channel.auto_join_users).to eq(true)
+
+    expected_members_count = GroupUser.where(group: group).count
+    memberships_count =
+      UserChatChannelMembership.automatic.where(chat_channel: channel, following: true).count
+
+    expect(memberships_count).to eq(expected_members_count)
+  end
+
+  it "seeds default channels" do
+    ChatSeeder.new.execute
+
+    staff_channel = ChatChannel.find_by(chatable: staff_category)
+    general_channel = ChatChannel.find_by(chatable: general_category)
+
+    assert_channel_was_correctly_seeded(staff_channel, Group[:staff])
+    assert_channel_was_correctly_seeded(general_channel, Group[:everyone])
+
+    expect(staff_category.custom_fields[Chat::HAS_CHAT_ENABLED]).to eq(true)
+    expect(general_category.reload.custom_fields[Chat::HAS_CHAT_ENABLED]).to eq(true)
+    expect(SiteSetting.needs_chat_seeded).to eq(false)
+  end
+
+  it "applies a name to the general category channel" do
+    expected_name = general_category.name
+
+    ChatSeeder.new.execute
+
+    general_channel = ChatChannel.find_by(chatable: general_category)
+    expect(general_channel.name).to eq(expected_name)
+  end
+
+  it "applies a name to the staff category channel" do
+    expected_name = staff_category.name
+
+    ChatSeeder.new.execute
+
+    staff_channel = ChatChannel.find_by(chatable: staff_category)
+    expect(staff_channel.name).to eq(expected_name)
+  end
+
+  it "does nothing when 'SiteSetting.needs_chat_seeded' is false" do
+    SiteSetting.needs_chat_seeded = false
+
+    expect { ChatSeeder.new.execute }.not_to change { ChatChannel.count }
+  end
+end