Check the hash given to #from_hash is a hash

hash_kit.gemspec

@@ -18,9 +18,9 @@ Gem::Specification.new do |spec|
   spec.executables   = spec.files.grep(%r{^exe/}) { |f| File.basename(f) }
   spec.require_paths = ['lib']
 
-  spec.add_development_dependency 'bundler', '~> 1.11'
+  spec.add_development_dependency 'bundler'
   spec.add_development_dependency 'pry'
-  spec.add_development_dependency 'rake', '~> 10.0'
+  spec.add_development_dependency 'rake'
   spec.add_development_dependency 'rspec'
   spec.add_development_dependency 'simplecov'
 end

lib/hash_kit/helper.rb

@@ -1,13 +1,15 @@
+# frozen_string_literal: true
+
 module HashKit
+  # Hash kit Helper class
   class Helper
-
-    #This method is called to make a hash allow indifferent access (it will accept both strings & symbols for a valid key).
+    # This method is called to make a hash allow indifferent access (it will
+    # accept both strings & symbols for a valid key).
     def indifferent!(hash)
-      unless hash.is_a?(Hash)
-        return
-      end
+      return unless hash.is_a?(Hash)
 
-      #set the default proc to allow the key to be either string or symbol if a matching key is found.
+      # Set the default proc to allow the key to be either string or symbol if
+      # a matching key is found.
       hash.default_proc = proc do |h, k|
         if h.key?(k.to_s)
           h[k.to_s]
@@ -18,9 +20,9 @@ def indifferent!(hash)
         end
       end
 
-      #recursively process any child hashes
+      # Recursively process any child hashes
       hash.each do |key,value|
-        if hash[key] != nil
+        unless hash[key].nil?
           if hash[key].is_a?(Hash)
             indifferent!(hash[key])
           elsif hash[key].is_a?(Array)
@@ -33,9 +35,7 @@ def indifferent!(hash)
     end
 
     def indifferent_array!(array)
-      unless array.is_a?(Array)
-        return
-      end
+      return unless array.is_a?(Array)
 
       array.each do |i|
         if i.is_a?(Hash)
@@ -46,14 +46,16 @@ def indifferent_array!(array)
       end
     end
 
-    #This method is called to convert all the keys of a hash into symbols to allow consistent usage of hashes within your Ruby application.
+    # This method is called to convert all the keys of a hash into symbols to
+    # allow consistent usage of hashes within your Ruby application.
     def symbolize(hash)
       {}.tap do |h|
         hash.each { |key, value| h[key.to_sym] = map_value_symbol(value) }
       end
     end
 
-    #This method is called to convert all the keys of a hash into strings to allow consistent usage of hashes within your Ruby application.
+    # This method is called to convert all the keys of a hash into strings to
+    # allow consistent usage of hashes within your Ruby application.
     def stringify(hash)
       {}.tap do |h|
         hash.each { |key, value| h[key.to_s] = map_value_string(value) }
@@ -73,18 +75,22 @@ def to_hash(obj)
       hash
     end
 
-    def from_hash(hash, klass, transforms =  [])
+    # Return an object of type klass from the values in the given hash
+    #
+    # @param [Hash] hash
+    # @param [Class] klass
+    # @param [Array] transforms
+    # @return [Object]
+    def from_hash(hash, klass, transforms = [])
       obj = klass.new
-      if hash ==nil || hash == {}
-        return obj
-      end
+      return obj if hash.nil? || hash.empty?
+      raise ArgumentError, "#{hash.inspect} is not a hash" unless hash.is_a?(Hash)
+
+      hash.each do |k, v|
+        next unless obj.respond_to?(k)
 
-      hash.each do |k,v|
-        if !obj.respond_to?(k)
-          next
-        end
         transform = transforms.detect { |t| t.key.to_sym == k.to_sym }
-        if transform != nil
+        if !transform.nil?
           if v.is_a?(Hash)
             child = from_hash(v, transform.klass, transforms)
             obj.instance_variable_set("@#{k}", child)
@@ -98,7 +104,8 @@ def from_hash(hash, klass, transforms =  [])
           obj.instance_variable_set("@#{k}", v)
         end
       end
-      return obj
+
+      obj
     end
 
     private

script/docker-compose.yml

@@ -1,6 +1,7 @@
-gem_test_runner:
-  image: codeguru/ruby:2.3.1-alpine-3.4
-  container_name: gem_test_runner
-  command: bash -c "while true; do echo 'Container is running...'; sleep 2; done"
-  volumes:
-      - ../:/gem_src
+services:
+  gem_test_runner:
+    image: ruby:2.7.6-bullseye
+    container_name: gem_test_runner
+    command: bash -c "while true; do echo 'Container is running...'; sleep 2; done"
+    volumes:
+        - ../:/gem_src

spec/hash_kit/helper_spec.rb

@@ -1,8 +1,9 @@
+# frozen_string_literal: true
+
 require 'spec_helper'
 
 RSpec.describe HashKit::Helper do
   describe '#symbolize' do
-
     context 'when a single layer hash with string keys is specified' do
       let(:hash) { { 'key1' => 'value1', 'key2' => 'value2' } }
 
@@ -64,7 +65,6 @@
   end
 
   describe '#stringify' do
-
     context 'when a single layer hash with symbol keys is specified' do
       let(:hash) { { :key1 => 'value1', :key2 => 'value2' } }
 
@@ -122,11 +122,9 @@
         expect(new_hash['key3'][1].has_key?(:key4)).to be false
       end
     end
-
   end
 
   describe '#to_hash' do
-
     let(:key1) do
       { key1: 'value1' }
     end
@@ -195,7 +193,7 @@
     end
 
     [
-      "string"    ,  
+      'string'    ,  
       101         ,
       1.01        ,
       Time.now    ,
@@ -237,36 +235,35 @@
   end
 
   describe '#from_hash' do
-
     let(:child_hash) do
       {
-          text: 'abc',
-          numeric: 5,
-          time: Time.now,
-          invalid_key: 5,
-          bool: true
+        text: 'abc',
+        numeric: 5,
+        time: Time.now,
+        invalid_key: 5,
+        bool: true
       }
     end
 
     let(:parent_hash) do
       {
-          text: 'abc',
-          numeric: 5,
-          time: Time.now,
-          entity: child_hash,
-          entity_array: [child_hash, child_hash],
-          invalid_key: 5,
-          bool: true
+        text: 'abc',
+        numeric: 5,
+        time: Time.now,
+        entity: child_hash,
+        entity_array: [child_hash, child_hash],
+        invalid_key: 5,
+        bool: true
       }
     end
 
     let(:string_hash) do
       {
-          'text' => 'abc',
-          'numeric' => 5,
-          'time' => Time.now,
-          'invalid_key' => 5,
-          'bool' => true
+        'text' => 'abc',
+        'numeric' => 5,
+        'time' => Time.now,
+        'invalid_key' => 5,
+        'bool' => true
       }
     end
 
@@ -337,6 +334,12 @@
         expect(obj.entity_array[1]).to be_a(TestEntity)
       end
     end
+
+    context 'when hash is not a hash' do
+      it 'raises an ArgumentError' do
+        expect { subject.from_hash('Not a hash', TestEntity, transforms) }.to raise_error(ArgumentError)
+      end
+    end
   end
 
   describe '#indifferent' do
@@ -356,18 +359,22 @@
           }
       }
     end
+
     it 'should allow access to a string key from a symbol' do
       subject.indifferent!(hash)
       expect(hash[:key1]).to eq 'value1'
     end
+
     it 'should allow access to a symbol key from a string' do
       subject.indifferent!(hash)
       expect(hash['key2']).to eq 'value2'
     end
+
     it 'should allow indifferent access to a key within an array' do
       subject.indifferent!(hash)
       expect(hash[:key3][0]['key4']).to eq 'value4'
     end
+
     it 'should allow indifferent access to a key within an nested hash' do
       subject.indifferent!(hash)
       expect(hash[:key6]['key7']).to eq 'value7'