(HC-33) Support adding element when array does not exist yet

lib/puppet/provider/hocon_setting/ruby.rb

@@ -11,16 +11,21 @@ def self.namevar(section_name, setting)
   end
 
   def exists?
-    if resource[:type] == 'array_element'
-      Array(@resource[:value]).each do |v|
-        if value.flatten.include?(v)
-          return true
+    ret_value = false
+
+    if conf_file.has_value?(setting)
+      if resource[:type] == 'array_element'
+        Array(@resource[:value]).each do |v|
+          if value.flatten.include?(v)
+            return true
+          end
         end
+      else
+        ret_value = true
       end
-      return false
-    else
-      conf_file.has_value?(setting)
     end
+
+    return ret_value
   end
 
   def create
@@ -44,13 +49,22 @@ def type=(value)
   end
 
   def value
-    val = conf_object.get_value(setting).unwrapped
-
-    # This is required because of :array_matching => :all.
-    # Without this, Puppet will almost always register changes
-    # to a hocon_setting even when it shouldn't.
+    val = conf_file.has_value?(setting) ?
+        conf_object.get_value(setting).unwrapped : []
     unless val.is_a?(Array)
-      val = [val]
+      if resource[:type] == 'array_element'
+        # If the current value of the target setting is not an array,
+        # present the current value as an empty array so that an
+        # element is added to an empty array (as opposed to converting
+        # the current value into the first element in an array and
+        # adding the value to set as a second element in the array).
+        val = []
+      else
+        # This is required because of :array_matching => :all.
+        # Without this, Puppet will almost always register changes
+        # to a hocon_setting even when it shouldn't.
+        val = [val]
+      end
     end
     val
   end

spec/unit/puppet/provider/conf_setting/ruby_spec.rb

@@ -110,6 +110,90 @@ def validate_file(expected_content,tmpfile = tmpfile)
       EOS
 )
     end
+
+    it "should add an array element even if the target setting does not yet exist" do
+      resource = Puppet::Type::Hocon_setting.new(
+          common_params.merge(:setting => 'test_key_2',
+                              :ensure => 'present',
+                              :value => { 'foo' => 'foovalue3' },
+                              :type => 'array_element'))
+      provider = described_class.new(resource)
+      expect(provider.exists?).to be false
+      provider.create
+      validate_file(
+          <<-EOS
+test_key_1: [
+  {
+    foo: foovalue
+    bar: barvalue
+    master: true
+  }
+,
+  {
+    foo: foovalue2
+    baz: bazvalue
+    url: "http://192.168.1.1:8080"
+  }
+,
+  {
+    foo: foovalue3
+  }
+]
+test_key_2 : [
+
+    {
+
+        "foo" : "foovalue3"
+
+    }
+
+
+
+]
+      EOS
+      )
+    end
+
+    it "should add an array element even if the target setting is not an array" do
+      File.open(tmpfile, 'a') do |fh|
+        fh.write('test_key_2: 3')
+      end
+      resource = Puppet::Type::Hocon_setting.new(
+          common_params.merge(:setting => 'test_key_2',
+                              :ensure => 'present',
+                              :value => { 'foo' => 'foovalue3' },
+                              :type => 'array_element'))
+      provider = described_class.new(resource)
+      expect(provider.exists?).to be false
+      provider.create
+      validate_file(
+          <<-EOS
+test_key_1: [
+  {
+    foo: foovalue
+    bar: barvalue
+    master: true
+  }
+,
+  {
+    foo: foovalue2
+    baz: bazvalue
+    url: "http://192.168.1.1:8080"
+  }
+,
+  {
+    foo: foovalue3
+  }
+]
+test_key_2: [
+    {
+        "foo" : "foovalue3"
+    }
+
+]
+      EOS
+      )
+    end
   end
 
   context "when ensuring that a setting is present" do