feat(format): add * format option

Preserves source formatting

README.md

@@ -641,6 +641,7 @@ The content that may contain CoffeeScript classes to convert to AngularJS module
 
 #### options
 Type: `Object`  
+Default: `undefined`  
 
 
 ##### options.appName
@@ -710,6 +711,7 @@ Default: `{format: 'camelCase'}`
 ### Supported Formats
 Format | Example
 --- | ---
+* | *no change*
 camelCase | camelCase
 lowerCamelCase | lowerCamelCase
 lowerCase | lowercase

lib/changeCase.coffee

@@ -1,6 +1,9 @@
 caseChangeRegEx = /([a-z\d])([A-Z])/g
 
 module.exports = (input, caseFormat) ->
+	return if caseFormat is '*'
+		input
+
 	return if caseFormat in ['camelCase', 'lowerCamelCase']
 		input[0].toLowerCase() + input[1..]
 

test/changeCase.spec.coffee

@@ -1,6 +1,20 @@
 changeCase = require '../lib/changeCase'
 
 describe 'formatOptions', ->
+	it 'should not change the source casing', ->
+		format      = '*'
+		input       = 'myInput'
+		result      = changeCase input, format
+		expectation = 'myInput'
+
+		expect(result).toEqual(expectation)
+
+		input       = 'MyInput'
+		result      = changeCase input, format
+		expectation = 'MyInput'
+
+		expect(result).toEqual(expectation)
+
 	it 'should change to camelCase', ->
 		format      = 'camelCase'
 		input       = 'myInput'