Do not add schema / class name mapping where custom mapping exists

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

@@ -1209,10 +1209,25 @@ public String toString() {
         return sb.toString();
     }
 
-    public void addDiscriminatorMappedModelsImports() {
+    /*
+     * To clean up mapped models if needed and add mapped models to imports
+     *
+     * @param cleanUpMappedModels Clean up mapped models if set to true
+     */
+    public void addDiscriminatorMappedModelsImports(boolean cleanUpMappedModels) {
         if (discriminator == null || discriminator.getMappedModels() == null) {
             return;
         }
+
+        if (cleanUpMappedModels && !this.hasChildren && // no child
+                (this.oneOf == null || this.oneOf.isEmpty()) && // not oneOf
+                (this.anyOf == null || this.anyOf.isEmpty())) { // not anyOf
+            //clear the mapping
+            discriminator.setMappedModels(null);
+            return;
+        }
+
+        // import child schemas defined in mapped models
         for (CodegenDiscriminator.MappedModel mm : discriminator.getMappedModels()) {
             if (!"".equals(mm.getModelName())) {
                 imports.add(mm.getModelName());

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

@@ -50,6 +50,7 @@
 import org.openapitools.codegen.api.TemplatingEngineAdapter;
 import org.openapitools.codegen.config.GlobalSettings;
 import org.openapitools.codegen.examples.ExampleGenerator;
+import org.openapitools.codegen.languages.PythonClientCodegen;
 import org.openapitools.codegen.languages.RustServerCodegen;
 import org.openapitools.codegen.meta.FeatureSet;
 import org.openapitools.codegen.meta.GeneratorMetadata;
@@ -611,6 +612,7 @@ public Map<String, CodegenModel> getAllModels(Map<String, ModelsMap> objs) {
 
     /**
      * Loop through all models to update different flags (e.g. isSelfReference), children models, etc
+     * and update mapped models for import.
      *
      * @param objs Map of models
      * @return maps of models with various updates
@@ -661,10 +663,17 @@ public Map<String, ModelsMap> updateAllModels(Map<String, ModelsMap> objs) {
         }
 
         // loop through properties of each model to detect self-reference
+        // and update mapped models for import
         for (ModelsMap entry : objs.values()) {
             for (ModelMap mo : entry.getModels()) {
                 CodegenModel cm = mo.getModel();
                 removeSelfReferenceImports(cm);
+
+                if (!this.getLegacyDiscriminatorBehavior()) {
+                    // skip cleaning up mapped models for python client generator
+                    // which uses its own logic
+                    cm.addDiscriminatorMappedModelsImports(!(this instanceof PythonClientCodegen));
+                }
             }
         }
         setCircularReferences(allModels);
@@ -2655,9 +2664,6 @@ protected void updateModelForComposedSchema(CodegenModel m, Schema schema, Map<S
                     if (m.discriminator == null && innerSchema.getDiscriminator() != null) {
                         LOGGER.debug("discriminator is set to null (not correctly set earlier): {}", m.name);
                         m.setDiscriminator(createDiscriminator(m.name, innerSchema, this.openAPI));
-                        if (!this.getLegacyDiscriminatorBehavior()) {
-                            m.addDiscriminatorMappedModelsImports();
-                        }
                         modelDiscriminators++;
                     }
 
@@ -2812,6 +2818,7 @@ protected void updateModelForComposedSchema(CodegenModel m, Schema schema, Map<S
         if (Boolean.TRUE.equals(schema.getNullable())) {
             m.isNullable = Boolean.TRUE;
         }
+
         // end of code block for composed schema
     }
 
@@ -2999,9 +3006,6 @@ public CodegenModel fromModel(String name, Schema schema) {
         m.isAlias = (typeAliases.containsKey(name)
                 || isAliasOfSimpleTypes(schema)); // check if the unaliased schema is an alias of simple OAS types
         m.setDiscriminator(createDiscriminator(name, schema, this.openAPI));
-        if (!this.getLegacyDiscriminatorBehavior()) {
-            m.addDiscriminatorMappedModelsImports();
-        }
 
         if (schema.getDeprecated() != null) {
             m.isDeprecated = schema.getDeprecated();
@@ -3455,15 +3459,15 @@ protected List<MappedModel> getAllOfDescendants(String thisSchemaName, OpenAPI o
                 break;
             }
             currentSchemaName = queue.remove(0);
-            MappedModel mm = new MappedModel(currentSchemaName, toModelName(currentSchemaName));
-            descendentSchemas.add(mm);
             Schema cs = schemas.get(currentSchemaName);
             Map<String, Object> vendorExtensions = cs.getExtensions();
-            if (vendorExtensions != null && !vendorExtensions.isEmpty() && vendorExtensions.containsKey("x-discriminator-value")) {
-                String xDiscriminatorValue = (String) vendorExtensions.get("x-discriminator-value");
-                mm = new MappedModel(xDiscriminatorValue, toModelName(currentSchemaName));
-                descendentSchemas.add(mm);
-            }
+            String mappingName =
+                Optional.ofNullable(vendorExtensions)
+                    .map(ve -> ve.get("x-discriminator-value"))
+                    .map(discriminatorValue -> (String) discriminatorValue)
+                    .orElse(currentSchemaName);
+            MappedModel mm = new MappedModel(mappingName, toModelName(currentSchemaName));
+            descendentSchemas.add(mm);
         }
         return descendentSchemas;
     }
@@ -3513,10 +3517,11 @@ protected CodegenDiscriminator createDiscriminator(String schemaName, Schema sch
             // for schemas that allOf inherit from this schema, add those descendants to this discriminator map
             List<MappedModel> otherDescendants = getAllOfDescendants(schemaName, openAPI);
             for (MappedModel otherDescendant : otherDescendants) {
-                // add only if the mapping names are not the same
+                // add only if the mapping names are not the same and the model names are not the same
                 boolean matched = false;
                 for (MappedModel uniqueDescendant : uniqueDescendants) {
-                    if (uniqueDescendant.getMappingName().equals(otherDescendant.getMappingName())) {
+                    if (uniqueDescendant.getMappingName().equals(otherDescendant.getMappingName())
+                        || (uniqueDescendant.getModelName().equals(otherDescendant.getModelName()))) {
                         matched = true;
                         break;
                     }
@@ -7756,9 +7761,7 @@ public void addOneOfInterfaceModel(ComposedSchema cs, String type, OpenAPI openA
         CodegenModel cm = new CodegenModel();
 
         cm.setDiscriminator(createDiscriminator("", cs, openAPI));
-        if (!this.getLegacyDiscriminatorBehavior()) {
-            cm.addDiscriminatorMappedModelsImports();
-        }
+
         for (Schema o : Optional.ofNullable(cs.getOneOf()).orElse(Collections.emptyList())) {
             if (o.get$ref() == null) {
                 if (cm.discriminator != null && o.get$ref() == null) {

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

@@ -337,12 +337,6 @@ public ModelsMap postProcessModels(ModelsMap objs) {
         objs = super.postProcessModels(objs);
         List<ModelMap> models = objs.getModels();
         ProcessUtils.addIndexToProperties(models, 1);
-
-        for (ModelMap mo : models) {
-            CodegenModel cm = mo.getModel();
-            cm.imports = rewriteImports(cm.imports, true);
-            cm.vendorExtensions.put("x-has-vars", !cm.vars.isEmpty());
-        }
         return objs;
     }
 
@@ -583,6 +577,16 @@ public Map<String, ModelsMap> postProcessAllModels(Map<String, ModelsMap> objs)
             adaptToDartInheritance(objs);
             syncRootTypesWithInnerVars(objs);
         }
+
+        // loop through models to update the imports
+        for (ModelsMap entry : objs.values()) {
+            for (ModelMap mo : entry.getModels()) {
+                CodegenModel cm = mo.getModel();
+                cm.imports = rewriteImports(cm.imports, true);
+                cm.vendorExtensions.put("x-has-vars", !cm.vars.isEmpty());
+            }
+        }
+
         return objs;
     }
 
@@ -730,6 +734,10 @@ private Set<String> rewriteImports(Set<String> originalImports, boolean isModel)
                 resultImports.add(i);
             } else if (importMapping().containsKey(modelImport)) {
                 resultImports.add(importMapping().get(modelImport));
+            } else if (modelImport.startsWith("dart:")) { // import dart:* directly
+                resultImports.add(modelImport);
+            } else if (modelImport.startsWith("package:")) { // e.g. package:openapi/src/model/child.dart
+                resultImports.add(modelImport);
             } else {
                 resultImports.add("package:" + pubName + "/" + sourceFolder + "/" + modelPackage() + "/" + underscore(modelImport) + ".dart");
             }

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

@@ -2438,8 +2438,17 @@ protected void updateModelForComposedSchema(CodegenModel m, Schema schema, Map<S
                 if (m.discriminator == null && innerSchema.getDiscriminator() != null) {
                     LOGGER.debug("discriminator is set to null (not correctly set earlier): {}", m.name);
                     m.setDiscriminator(createDiscriminator(m.name, innerSchema, this.openAPI));
+                    // directly include the function `addDiscriminatorMappedModelsImports` inline below
+                    // as the function has been updated
+                    //m.addDiscriminatorMappedModelsImports();
                     if (!this.getLegacyDiscriminatorBehavior()) {
-                        m.addDiscriminatorMappedModelsImports();
+                        if (m.discriminator != null && m.discriminator.getMappedModels() != null) {
+                            for (CodegenDiscriminator.MappedModel mm : m.discriminator.getMappedModels()) {
+                                if (!"".equals(mm.getModelName())) {
+                                    m.getImports().add(mm.getModelName());
+                                }
+                            }
+                        }
                     }
                     modelDiscriminators++;
                 }

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

@@ -1101,7 +1101,6 @@ public void testComposedSchemaAllOfDiscriminatorMap() {
         cm = codegen.fromModel(modelName, sc);
         hs.clear();
         hs.add(new CodegenDiscriminator.MappedModel("b", codegen.toModelName("B")));
-        hs.add(new CodegenDiscriminator.MappedModel("B", codegen.toModelName("B")));
         hs.add(new CodegenDiscriminator.MappedModel("C", codegen.toModelName("C")));
         Assert.assertEquals(cm.getHasDiscriminatorWithNonEmptyMapping(), true);
         Assert.assertEquals(cm.discriminator.getMappedModels(), hs);
@@ -1585,8 +1584,6 @@ public void verifyXDiscriminatorValue() {
         discriminator.setPropertyBaseName(prop);
         discriminator.setMapping(null);
         discriminator.setMappedModels(new HashSet<CodegenDiscriminator.MappedModel>() {{
-            add(new CodegenDiscriminator.MappedModel("DailySubObj", "DailySubObj"));
-            add(new CodegenDiscriminator.MappedModel("SubObj", "SubObj"));
             add(new CodegenDiscriminator.MappedModel("daily", "DailySubObj"));
             add(new CodegenDiscriminator.MappedModel("sub-obj", "SubObj"));
         }});
@@ -1984,8 +1981,6 @@ private void verifyPersonDiscriminator(CodegenDiscriminator discriminator) {
         test.getMapping().put("c", "Child");
         test.getMappedModels().add(new CodegenDiscriminator.MappedModel("a", "Adult"));
         test.getMappedModels().add(new CodegenDiscriminator.MappedModel("c", "Child"));
-        test.getMappedModels().add(new CodegenDiscriminator.MappedModel("Adult", "Adult"));
-        test.getMappedModels().add(new CodegenDiscriminator.MappedModel("Child", "Child"));
         Assert.assertEquals(discriminator, test);
     }