Use conversations_list instead of deprecated channels_list

lib/slack/web/api/endpoints.rb

@@ -64,6 +64,7 @@ module Slack
   module Web
     module Api
       module Endpoints
+        include Slack::Web::Api::Mixins::Conversations
         include Slack::Web::Api::Mixins::Channels
         include Slack::Web::Api::Mixins::Users
         include Slack::Web::Api::Mixins::Groups

lib/slack/web/api/mixins.rb

@@ -1,5 +1,6 @@
 # frozen_string_literal: true
 require_relative 'mixins/channels.id'
+require_relative 'mixins/conversations.id'
 require_relative 'mixins/users.id'
 require_relative 'mixins/users.search'
 require_relative 'mixins/groups.id'

lib/slack/web/api/mixins/conversations.id.rb

@@ -0,0 +1,27 @@
+# frozen_string_literal: true
+require_relative 'ids.id'
+
+module Slack
+  module Web
+    module Api
+      module Mixins
+        module Conversations
+          include Ids
+          #
+          # This method returns a channel ID given a channel name.
+          #
+          # @option options [channel] :channel
+          #   Channel to get ID for, prefixed with #.
+          def conversations_id(options = {})
+            name = options[:channel]
+            throw ArgumentError.new('Required arguments :channel missing') if name.nil?
+
+            id_for(:channel, name, '#', :channels, 'channel_not_found') do
+              conversations_list
+            end
+          end
+        end
+      end
+    end
+  end
+end

lib/slack/web/api/templates/method.erb

@@ -40,7 +40,7 @@ module Slack
 <% if data['group'] == 'groups' && data['args']['channel'] && !data['args']['channel']['desc'].include?('Can be an encoded ID, or a name.') %>
             options = options.merge(channel: groups_id(options)['group']['id']) if options[:channel]
 <% elsif data['args']['channel'] && !data['args']['channel']['desc'].include?('Can be an encoded ID, or a name.') %>
-            options = options.merge(channel: channels_id(options)['channel']['id']) if options[:channel]
+            options = options.merge(channel: conversations_id(options)['channel']['id']) if options[:channel]
 <% end %>
 <% if data['args']['user'] %>
             options = options.merge(user: users_id(options)['user']['id']) if options[:user]

lib/tasks/web.rake

@@ -2,6 +2,8 @@
 # largely from https://github.com/aki017/slack-ruby-gem
 require 'json-schema'
 require 'erubis'
+require 'active_support'
+require 'active_support/core_ext'
 
 namespace :slack do
   namespace :web do

spec/slack/web/api/mixins/conversations_spec.rb

@@ -0,0 +1,43 @@
+# frozen_string_literal: true
+require 'spec_helper'
+
+RSpec.describe Slack::Web::Api::Mixins::Conversations do
+  subject(:conversations) do
+    klass.new
+  end
+
+  let(:klass) do
+    Class.new do
+      include Slack::Web::Api::Mixins::Conversations
+    end
+  end
+
+  before do
+    allow(conversations).to receive(:conversations_list).and_return(
+      Slack::Messages::Message.new(
+        'channels' => [{
+          'id' => 'CDEADBEEF',
+          'name' => 'general'
+        }]
+      )
+    )
+  end
+
+  context '#conversations_id' do
+    it 'leaves channels specified by ID alone' do
+      expect(conversations.conversations_id(channel: 'C123456')).to(
+        eq('ok' => true, 'channel' => { 'id' => 'C123456' })
+      )
+    end
+    it 'translates a channel that starts with a #' do
+      expect(conversations.conversations_id(channel: '#general')).to(
+        eq('ok' => true, 'channel' => { 'id' => 'CDEADBEEF' })
+      )
+    end
+    it 'fails with an exception' do
+      expect { conversations.conversations_id(channel: '#invalid') }.to(
+        raise_error(Slack::Web::Api::Errors::SlackError, 'channel_not_found')
+      )
+    end
+  end
+end