Further improved objc compatibility

- Models: Expose non-optional variables to @objc. Otherwise e.g. Int64 is not visible in objc
- Models: Try avoiding generated code that has boolVariable.map ({ return NSNumber(value: $0) }) as map does not exist for Bool in Swift (see Issue OpenAPITools#1456)
- API: Avoid Void? arguments with @objc, as they are not available in objc

modules/openapi-generator/src/main/resources/swift4/api.mustache

@@ -40,18 +40,20 @@ extension {{projectName}}API {
      - parameter {{paramName}}: ({{#isFormParam}}form{{/isFormParam}}{{#isQueryParam}}query{{/isQueryParam}}{{#isPathParam}}path{{/isPathParam}}{{#isHeaderParam}}header{{/isHeaderParam}}{{#isBodyParam}}body{{/isBodyParam}}) {{description}} {{^required}}(optional{{#defaultValue}}, default to {{{.}}}{{/defaultValue}}){{/required}}{{/allParams}}
      - parameter completion: completion handler to receive the data and the error objects
      */
-    {{#objcCompatible}}@objc {{/objcCompatible}}open class func {{operationId}}({{#allParams}}{{paramName}}: {{#isEnum}}{{#isContainer}}{{{dataType}}}{{/isContainer}}{{^isContainer}}{{{datatypeWithEnum}}}_{{operationId}}{{/isContainer}}{{/isEnum}}{{^isEnum}}{{{dataType}}}{{/isEnum}}{{^required}}? = nil{{/required}}{{#hasMore}}, {{/hasMore}}{{/allParams}}{{#hasParams}}, {{/hasParams}}completion: @escaping ((_ data: {{#returnType}}{{{returnType}}}{{/returnType}}{{^returnType}}Void{{/returnType}}?,_ error: Error?) -> Void)) {
+    {{#objcCompatible}}@objc {{/objcCompatible}}open class func {{operationId}}({{#allParams}}{{paramName}}: {{#isEnum}}{{#isContainer}}{{{dataType}}}{{/isContainer}}{{^isContainer}}{{{datatypeWithEnum}}}_{{operationId}}{{/isContainer}}{{/isEnum}}{{^isEnum}}{{{dataType}}}{{/isEnum}}{{^required}}? = nil{{/required}}{{#hasMore}}, {{/hasMore}}{{/allParams}}{{#hasParams}}, {{/hasParams}}completion: @escaping (({{#returnType}}_ data: {{{returnType}}}?,{{/returnType}}{{^returnType}}{{^objcCompatible}}_ data: Void?,{{/objcCompatible}}{{/returnType}}_ error: Error?) -> Void)) {
         {{operationId}}WithRequestBuilder({{#allParams}}{{paramName}}: {{paramName}}{{#hasMore}}, {{/hasMore}}{{/allParams}}).execute { (response, error) -> Void in
         {{#returnType}}
             completion(response?.body, error)
         {{/returnType}}
-        {{^returnType}}
+        {{^returnType}}{{#objcCompatible}}
+        completion(error)
+        {{/objcCompatible}}{{^objcCompatible}}
             if error == nil {
                 completion((), error)
             } else {
                 completion(nil, error)
             }
-        {{/returnType}}
+        {{/objcCompatible}}{{/returnType}}
         }
     }
 

modules/openapi-generator/src/main/resources/swift4/modelObject.mustache

@@ -13,17 +13,17 @@
 {{/isEnum}}
 {{^isEnum}}
     {{#description}}/** {{description}} */
-    {{/description}}{{#objcCompatible}}@objc {{/objcCompatible}}public var {{name}}: {{{datatype}}}{{#unwrapRequired}}?{{/unwrapRequired}}{{^unwrapRequired}}{{^required}}?{{/required}}{{/unwrapRequired}}{{#defaultValue}} = {{{defaultValue}}}{{/defaultValue}}{{#objcCompatible}}{{#vendorExtensions.x-swift-optional-scalar}}
+    {{/description}}{{#objcCompatible}}{{#required}}@objc {{/required}}{{^required}}{{^vendorExtensions.x-swift-optional-scalar}}@objc {{/vendorExtensions.x-swift-optional-scalar}}{{/required}}{{/objcCompatible}}public var {{name}}: {{{datatype}}}{{#unwrapRequired}}?{{/unwrapRequired}}{{^unwrapRequired}}{{^required}}?{{/required}}{{/unwrapRequired}}{{#defaultValue}} = {{{defaultValue}}}{{/defaultValue}}{{#objcCompatible}}{{#vendorExtensions.x-swift-optional-scalar}}
     @objc public var {{name}}Num: NSNumber? {
         get {
-            return {{name}}.map({ return NSNumber(value: $0) })
+            return {{name}} as NSNumber?
         }
     }{{/vendorExtensions.x-swift-optional-scalar}}{{/objcCompatible}}
 {{/isEnum}}
 {{/allVars}}
 
 {{#hasVars}}
-    {{#objcCompatible}}@objc {{/objcCompatible}}public init({{#allVars}}{{name}}: {{{datatypeWithEnum}}}{{#unwrapRequired}}?{{/unwrapRequired}}{{^unwrapRequired}}{{^required}}?{{/required}}{{/unwrapRequired}}{{#hasMore}}, {{/hasMore}}{{/allVars}}) {
+   public init({{#allVars}}{{name}}: {{{datatypeWithEnum}}}{{#unwrapRequired}}?{{/unwrapRequired}}{{^unwrapRequired}}{{^required}}?{{/required}}{{/unwrapRequired}}{{#hasMore}}, {{/hasMore}}{{/allVars}}) {
         {{#allVars}}
         self.{{name}} = {{name}}
         {{/allVars}}