(#8709) Add hash merging function

In Puppet, it is not possible to reassign hash
values.

This function allows a reasonable way to perform
hash munging in Puppet.

Reviewed-by: Jeff McCune

1 files changed, 54 insertions, 0 deletions

diff --git a/spec/unit/puppet/parser/functions/merge_spec.rb b/spec/unit/puppet/parser/functions/merge_spec.rb
new file mode 100644
index 0000000..71e1869
--- /dev/null
+++ b/spec/unit/puppet/parser/functions/merge_spec.rb
@@ -0,0 +1,54 @@
+require 'puppet'
+require 'mocha'
+describe Puppet::Parser::Functions.function(:merge) do
+
+  # Pulled from Dan's create_resources function
+  # TODO - these let statements should be moved somewhere
+  # where they can be resued
+  let(:compiler) {
+    topscope = Puppet::Parser::Scope.new
+    # This is necessary so we don't try to use the compiler to discover our parent.
+    topscope.parent = nil
+    my_scope = Puppet::Parser::Scope.new
+    my_scope.compiler = Puppet::Parser::Compiler.new(Puppet::Node.new("floppy", :environment => 'production'))
+    my_scope.parent = topscope
+    compiler = my_scope.compiler
+  }
+  let(:scope) {
+    scope = Puppet::Parser::Scope.new
+    scope.stubs(:environment).returns(Puppet::Node::Environment.new('production'))
+    scope
+  }
+
+  describe 'when calling merge from puppet' do
+    it "should not compile when no arguments are passed" do
+      Puppet[:code] = 'merge()'
+      expect { compiler.compile }.should raise_error(Puppet::ParseError, /wrong number of arguments/)
+    end
+    it "should not compile when 1 argument is passed" do
+      Puppet[:code] = "$my_hash={'one' => 1}\nmerge($my_hash)"
+      expect { compiler.compile }.should raise_error(Puppet::ParseError, /wrong number of arguments/)
+    end
+  end
+  describe 'when calling merge on the scope instance' do
+    it 'should require all parameters are hashes' do
+      expect { new_hash = scope.function_merge([{}, '2'])}.should raise_error(Puppet::ParseError, /unexpected argument type String/)
+
+    end
+    it 'should be able to merge two hashes' do
+      new_hash = scope.function_merge([{'one' => '1', 'two' => '1'}, {'two' => '2', 'three' => '2'}])
+      new_hash['one'].should   == '1'
+      new_hash['two'].should   == '2'
+      new_hash['three'].should == '2'
+    end
+    it 'should merge multiple hashes' do
+      hash = scope.function_merge([{'one' => 1}, {'one' => '2'}, {'one' => '3'}])
+      hash['one'].should == '3'
+    end
+    it 'should accept empty hashes' do
+      scope.function_merge([{},{},{}]).should == {}
+    end
+
+  end
+
+end