Merge pull request #30 from cjlarose/allow-missing-manifest-file

Consider manifest to be empty if the corresponding manifest file does not exist

Author: rmacklin

lib/external_asset_pipeline/manifest.rb

@@ -29,6 +29,11 @@ def data
 
     def load
       JSON.parse(@config.manifest_path.read)
+    rescue Errno::ENOENT
+      warning = "No file exists at path #{@config.manifest_path}; "\
+        'treating it as an empty manifest'
+      @config.logger.warn warning
+      {}
     end
   end
 end

test/external_asset_pipeline/logger_double.rb

@@ -0,0 +1,12 @@
+# frozen_string_literal: true
+
+module ExternalAssetPipeline
+  class LoggerDouble
+    attr_reader :messages
+
+    def warn(message)
+      @messages ||= []
+      @messages << message
+    end
+  end
+end

test/external_asset_pipeline/manifest_test.rb

@@ -3,6 +3,7 @@
 require 'test_helper'
 
 require 'external_asset_pipeline/configuration'
+require 'external_asset_pipeline/logger_double'
 require 'external_asset_pipeline/manifest'
 
 module ExternalAssetPipeline
@@ -46,6 +47,20 @@ def test_find_when_manifest_values_include_prefix
       assert_nil manifest.find('missing-asset.css')
     end
 
+    def test_find_when_manifest_file_does_not_exist
+      config = Configuration.new
+      config.public_path = Pathname.new(TEST_APP_PUBLIC_PATH)
+      config.manifest_filename = 'bogus_manifest.json'
+      config.logger = LoggerDouble.new
+
+      manifest = Manifest.new(config)
+      assert_nil manifest.find 'application.js'
+
+      expected_log_warning = "No file exists at path #{config.manifest_path}; "\
+        'treating it as an empty manifest'
+      assert_equal [expected_log_warning], config.logger.messages
+    end
+
     def test_manifest_caching
       config = Configuration.new
       config.public_path = Pathname.new(TEST_APP_PUBLIC_PATH)

test/external_asset_pipeline/server_manifest_test.rb

@@ -3,6 +3,7 @@
 require 'test_helper'
 
 require 'external_asset_pipeline/configuration'
+require 'external_asset_pipeline/logger_double'
 require 'external_asset_pipeline/server_double'
 require 'external_asset_pipeline/server_manifest'
 require 'json'
@@ -49,14 +50,5 @@ def test_find
       assert_equal [expected_log_warning] * 3, @config.logger.messages
       assert_equal '/packs/manifest.json', server_stub.path
     end
-
-    class LoggerDouble
-      attr_reader :messages
-
-      def warn(message)
-        @messages ||= []
-        @messages << message
-      end
-    end
   end
 end