Implement BigDecimal to Decimal in swift4 for currency data as type=string format=number (#3910)

Author: siilats

modules/openapi-generator/src/main/java/org/openapitools/codegen/DefaultCodegen.java

@@ -1068,7 +1068,7 @@ public DefaultCodegen() {
         typeMapping.put("file", "File");
         typeMapping.put("UUID", "UUID");
         typeMapping.put("URI", "URI");
-        //typeMapping.put("BigDecimal", "BigDecimal"); //TODO need the mapping?
+        typeMapping.put("BigDecimal", "BigDecimal"); //TODO need the mapping?
 
 
         instantiationTypes = new HashMap<String, String>();

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/Swift4Codegen.java

@@ -101,7 +101,8 @@ public Swift4Codegen() {
                         "UUID",
                         "URL",
                         "AnyObject",
-                        "Any")
+                        "Any",
+                        "Decimal")
         );
         defaultIncludes = new HashSet<>(
                 Arrays.asList(
@@ -115,7 +116,8 @@ public Swift4Codegen() {
                         "Any",
                         "Empty",
                         "AnyObject",
-                        "Any")
+                        "Any",
+                        "Decimal")
         );
 
         objcReservedWords = new HashSet<>(
@@ -198,6 +200,7 @@ public Swift4Codegen() {
         typeMapping.put("ByteArray", "Data");
         typeMapping.put("UUID", "UUID");
         typeMapping.put("URI", "String");
+        typeMapping.put("BigDecimal", "Decimal");
 
         importMapping = new HashMap<>();