Correct deep merge behavior #264

app/controllers/lookups_controller.rb

@@ -5,8 +5,8 @@ class LookupsController < ApplicationController
 
   def show
     @result = @key.lookup(@node)
-  rescue Hdm::Error => error
-    @error = error
+  rescue Hdm::Error => e
+    @error = e
 
     render action: "error"
   end

app/models/hiera_data/lookup.rb

@@ -51,7 +51,6 @@ def flat_hash_merge(values)
     def deep_merge(values)
       values.inject do |memo, value|
         memo ||= {}
-        raise Hdm::Error, "Merge strategy `deep` can only be used with hashes and arrays." unless value.is_a?(Hash) || value.is_a?(Array)
 
         DeepMerge.deep_merge!(memo, value, merge_hash_arrays: true)
       end

test/fixtures/files/puppet/environments/lookup_tests/data/common.yaml

@@ -19,6 +19,8 @@ hdm_nested_hash:
     integer: 32
     added_by_common: common
 hdm_mixed_types: 42
+hdm_mixed_types2:
+  from_common: 42
 lookup_options:
   '^hdm_duplicates':
     merge: hash

test/fixtures/files/puppet/environments/lookup_tests/data/nodes/lookup.betadots.training.yaml

@@ -16,3 +16,4 @@ hdm_nested_hash:
     integer: 5
 hdm_mixed_types:
   from_node: 23
+hdm_mixed_types2: 23

test/models/hiera_data/lookup_test.rb

@@ -118,6 +118,18 @@ class LookupTest < ActiveSupport::TestCase
       assert_equal expected, result
     end
 
+    test "looking up a mixed value key where a hash is on the highest layer with merge strategy `deep`" do
+      result = perform_lookup("hdm_mixed_types", merge_strategy: :deep)
+
+      assert_equal({ "from_node" => 23 }, result)
+    end
+
+    test "looking up a mixed value key where a hash is on the lowest layer with merge strategy `deep`" do
+      result = perform_lookup("hdm_mixed_types2", merge_strategy: :deep)
+
+      assert_equal 23, result
+    end
+
     private
 
     def perform_lookup(key, merge_strategy:)