Fix a regression with aliases on `Mash.load` (#459)

By switching to `YAML.safe_load`, we accidentally regressed the behavior of `Mash.load` by limiting the use of aliases within the YAML file. This restores the original behavior, but still uses `YAML.safe_load`.

5 files changed, 24 insertions, 4 deletions

diff --git a/.rubocop_todo.yml b/.rubocop_todo.yml
index e4e05c7..5d3da74 100644
--- a/.rubocop_todo.yml
+++ b/.rubocop_todo.yml
@@ -1,6 +1,6 @@
 # This configuration was generated by
 # `rubocop --auto-gen-config`
-# on 2018-08-11 15:53:09 -0500 using RuboCop version 0.52.1.
+# on 2018-08-14 21:37:22 -0500 using RuboCop version 0.52.1.
 # The point is for the user to remove these configuration records
 # one by one as the offenses are removed from the code base.
 # Note that changes in the inspected code, or installation of new
@@ -13,7 +13,7 @@ Metrics/AbcSize:
 # Offense count: 58
 # Configuration parameters: CountComments, ExcludedMethods.
 Metrics/BlockLength:
-  Max: 620
+  Max: 626
 
 # Offense count: 2
 # Configuration parameters: CountComments.
@@ -48,7 +48,7 @@ Style/IfUnlessModifier:
   Exclude:
     - 'lib/hashie/extensions/strict_key_access.rb'
 
-# Offense count: 261
+# Offense count: 263
 # Configuration parameters: AllowHeredoc, AllowURI, URISchemes, IgnoreCopDirectives, IgnoredPatterns.
 # URISchemes: http, https
 Metrics/LineLength:
diff --git a/CHANGELOG.md b/CHANGELOG.md
index ebebbb1..1cfbe5e 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -28,6 +28,7 @@ scheme are considered to be bugs.
 
 ### Fixed
 
+* [#459](https://github.com/intridea/hashie/pull/459): Fixed a regression in `Mash.load` that disallowed aliases - [@arekt](https://github.com/arekt) and [@michaelherold](https://github.com/michaelherold).
 * Your contribution here.
 
 ### Security
diff --git a/lib/hashie/extensions/parsers/yaml_erb_parser.rb b/lib/hashie/extensions/parsers/yaml_erb_parser.rb
index c2808de..d3b5c80 100644
--- a/lib/hashie/extensions/parsers/yaml_erb_parser.rb
+++ b/lib/hashie/extensions/parsers/yaml_erb_parser.rb
@@ -14,7 +14,7 @@ module Hashie
         def perform
           template = ERB.new(@content)
           template.filename = @file_path
-          YAML.safe_load template.result
+          YAML.safe_load template.result, [], [], true
         end
 
         def self.perform(file_path)
diff --git a/spec/fixtures/yaml_with_aliases.yml b/spec/fixtures/yaml_with_aliases.yml
new file mode 100644
index 0000000..f442c03
--- /dev/null
+++ b/spec/fixtures/yaml_with_aliases.yml
@@ -0,0 +1,11 @@
+accounts: &base_accounts
+  admin:
+    password: secret
+
+company_a:
+  accounts: &accounts
+    <<: *base_accounts
+
+# company_b:
+#   accounts: &accounts
+#     <<: *base_accounts
diff --git a/spec/hashie/mash_spec.rb b/spec/hashie/mash_spec.rb
index 680f403..b46bd6c 100644
--- a/spec/hashie/mash_spec.rb
+++ b/spec/hashie/mash_spec.rb
@@ -694,6 +694,14 @@ describe Hashie::Mash do
         expect(subject.object_id).to eq subject.object_id
       end
     end
+
+    context 'when the file has aliases in it' do
+      it 'can use the aliases and does not raise an error' do
+        mash = Hashie::Mash.load('spec/fixtures/yaml_with_aliases.yml')
+
+        expect(mash.company_a.accounts.admin.password).to eq('secret')
+      end
+    end
   end
 
   describe '#to_module(mash_method_name)' do