[all] add "x-enum-varnames" extension to control enum varname (#917)

* add "x-enum-varnames" extension to control the naming of the enum parameter name
* allow to set different size from target enum

Author: osjupiter

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

@@ -287,6 +287,8 @@ public Map<String, Object> postProcessModelsEnum(Map<String, Object> objs) {
                     enumVar.put("isString", isDataTypeString(cm.dataType));
                     enumVars.add(enumVar);
                 }
+                // if "x-enum-varnames" defined, update varnames
+                updateEnumVarsWithExtensions(enumVars, cm.getVendorExtensions());
                 cm.allowableValues.put("enumVars", enumVars);
             }
 
@@ -4003,6 +4005,8 @@ public void updateCodegenPropertyEnum(CodegenProperty var) {
             enumVar.put("isString", isDataTypeString(dataType));
             enumVars.add(enumVar);
         }
+        // if "x-enum-varnames" defined, update varnames
+        updateEnumVarsWithExtensions(enumVars, var.getVendorExtensions());
         allowableValues.put("enumVars", enumVars);
 
         // handle default value for enum, e.g. available => StatusEnum.AVAILABLE
@@ -4020,6 +4024,16 @@ public void updateCodegenPropertyEnum(CodegenProperty var) {
         }
     }
 
+    private void updateEnumVarsWithExtensions(List<Map<String, Object>> enumVars, Map<String, Object> vendorExtensions) {
+        if (vendorExtensions != null && vendorExtensions.containsKey("x-enum-varnames")) {
+            List<String> alias = (List<String>) vendorExtensions.get("x-enum-varnames");
+            int size = Math.min(enumVars.size(), alias.size());
+            for (int i = 0; i < size; i++) {
+                enumVars.get(i).put("name", alias.get(i));
+            }
+        }
+    }
+
     /**
      * If the pattern misses the delimiter, add "/" to the beginning and end
      * Otherwise, return the original pattern

modules/openapi-generator/src/test/java/org/openapitools/codegen/DefaultCodegenTest.java

@@ -306,6 +306,66 @@ public void updateCodegenPropertyEnum() {
         Assert.assertEquals(testedEnumVar.getOrDefault("isString", ""), false);
     }
 
+    @Test
+    public void updateCodegenPropertyEnumWithExtention() {
+        {
+            CodegenProperty enumProperty = codegenPropertyWithXEnumVarName(Arrays.asList("dog", "cat"), Arrays.asList("DOGVAR", "CATVAR"));
+            (new DefaultCodegen()).updateCodegenPropertyEnum(enumProperty);
+            List<Map<String, Object>> enumVars = (List<Map<String, Object>>) enumProperty.getAllowableValues().get("enumVars");
+            Assert.assertNotNull(enumVars);
+            Assert.assertNotNull(enumVars.get(0));
+            Assert.assertEquals(enumVars.get(0).getOrDefault("name", ""), "DOGVAR");
+            Assert.assertEquals(enumVars.get(0).getOrDefault("value", ""), "\"dog\"");
+            Assert.assertNotNull(enumVars.get(1));
+            Assert.assertEquals(enumVars.get(1).getOrDefault("name", ""), "CATVAR");
+            Assert.assertEquals(enumVars.get(1).getOrDefault("value", ""), "\"cat\"");
+        }
+        {
+            CodegenProperty enumProperty = codegenPropertyWithXEnumVarName(Arrays.asList("1", "2"), Arrays.asList("ONE", "TWO"));
+            (new DefaultCodegen()).updateCodegenPropertyEnum(enumProperty);
+            List<Map<String, Object>> enumVars = (List<Map<String, Object>>) enumProperty.getAllowableValues().get("enumVars");
+            Assert.assertEquals(enumVars.get(0).getOrDefault("name", ""), "ONE");
+            Assert.assertEquals(enumVars.get(0).getOrDefault("value", ""), "\"1\"");
+            Assert.assertEquals(enumVars.get(1).getOrDefault("name", ""), "TWO");
+            Assert.assertEquals(enumVars.get(1).getOrDefault("value", ""), "\"2\"");
+        }
+        {
+            CodegenProperty enumProperty = codegenPropertyWithXEnumVarName(Arrays.asList("a", "b", "c", "d"), Arrays.asList("FOO", "BAR"));
+            (new DefaultCodegen()).updateCodegenPropertyEnum(enumProperty);
+            List<Map<String, Object>> enumVars = (List<Map<String, Object>>) enumProperty.getAllowableValues().get("enumVars");
+            Assert.assertEquals(enumVars.get(0).getOrDefault("name", ""), "FOO");
+            Assert.assertEquals(enumVars.get(1).getOrDefault("name", ""), "BAR");
+            Assert.assertEquals(enumVars.get(2).getOrDefault("name", ""), "C");
+            Assert.assertEquals(enumVars.get(3).getOrDefault("name", ""), "D");
+        }
+        {
+            CodegenProperty enumProperty = codegenPropertyWithXEnumVarName(Arrays.asList("a", "b"), Arrays.asList("FOO", "BAR", "BAZ"));
+            (new DefaultCodegen()).updateCodegenPropertyEnum(enumProperty);
+            List<Map<String, Object>> enumVars = (List<Map<String, Object>>) enumProperty.getAllowableValues().get("enumVars");
+            Assert.assertEquals(enumVars.get(0).getOrDefault("name", ""), "FOO");
+            Assert.assertEquals(enumVars.get(1).getOrDefault("name", ""), "BAR");
+            Assert.assertEquals(enumVars.size(), 2);
+        }
+    }
+
+    @Test
+    public void postProcessModelsEnumWithExtention() {
+        final DefaultCodegen codegen = new DefaultCodegen();
+        Map<String, Object> objs = codegenModelWithXEnumVarName();
+        CodegenModel cm = (CodegenModel) ((Map<String, Object>) ((List<Object>) objs.get("models")).get(0)).get("model");
+
+        codegen.postProcessModelsEnum(objs);
+
+        List<Map<String, Object>> enumVars = (List<Map<String, Object>>) cm.getAllowableValues().get("enumVars");
+        Assert.assertNotNull(enumVars);
+        Assert.assertNotNull(enumVars.get(0));
+        Assert.assertEquals(enumVars.get(0).getOrDefault("name", ""), "DOGVAR");
+        Assert.assertEquals(enumVars.get(0).getOrDefault("value", ""), "\"dog\"");
+        Assert.assertNotNull(enumVars.get(1));
+        Assert.assertEquals(enumVars.get(1).getOrDefault("name", ""), "CATVAR");
+        Assert.assertEquals(enumVars.get(1).getOrDefault("value", ""), "\"cat\"");
+    }
+
     @Test
     public void testExample1() {
         final OpenAPI openAPI = new OpenAPIParser().readLocation("src/test/resources/3_0/examples.yaml", null, new ParseOptions()).getOpenAPI();
@@ -478,4 +538,30 @@ private CodegenProperty codegenPropertyWithArrayOfIntegerValues() {
         array.dataType = "Array";
         return array;
     }
+
+    private CodegenProperty codegenPropertyWithXEnumVarName(List<String> values, List<String> aliases) {
+        final CodegenProperty var = new CodegenProperty();
+        final HashMap<String, Object> allowableValues = new HashMap<>();
+        allowableValues.put("values", values);
+        var.setAllowableValues(allowableValues);
+        var.dataType = "String";
+        Map<String, Object> extentions = Collections.singletonMap("x-enum-varnames", aliases);
+        var.setVendorExtensions(extentions);
+        return var;
+    }
+
+    private Map<String, Object> codegenModelWithXEnumVarName() {
+        final CodegenModel cm = new CodegenModel();
+        cm.isEnum = true;
+        final HashMap<String, Object> allowableValues = new HashMap<>();
+        allowableValues.put("values", Arrays.asList("dog", "cat"));
+        cm.setAllowableValues(allowableValues);
+        cm.dataType = "String";
+        final List<String> aliases = Arrays.asList("DOGVAR", "CATVAR");
+        Map<String, Object> extentions = Collections.singletonMap("x-enum-varnames", aliases);
+        cm.setVendorExtensions(extentions);
+        cm.setVars(Collections.emptyList());
+        Map<String, Object> objs = Collections.singletonMap("models", Collections.singletonList(Collections.singletonMap("model", cm)));
+        return objs;
+    }
 }