[dart-dio] Fixes --model-name-suffix having no effect (OpenAPITools#5669)

Fixes OpenAPITools#5409

Author: josh-burton

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

@@ -19,6 +19,7 @@
 
 import io.swagger.v3.oas.models.media.ArraySchema;
 import io.swagger.v3.oas.models.media.Schema;
+
 import org.apache.commons.io.FilenameUtils;
 import org.apache.commons.lang3.StringUtils;
 import org.openapitools.codegen.*;
@@ -366,16 +367,23 @@ public String toModelName(String name) {
             name = "model_" + name; // e.g. 200Response => Model200Response (after camelize)
         }
 
-        // camelize the model name
-        // phone_number => PhoneNumber
-        return camelize(name);
+        if (typeMapping.containsValue(name)) {
+            return camelize(name);
+        } else {
+            // camelize the model name
+            return camelize(modelNamePrefix + "_" + name + "_" + modelNameSuffix);
+        }
     }
 
     @Override
     public String toModelFilename(String name) {
         return underscore(toModelName(name));
     }
 
+    @Override public String toModelDocFilename(String name) {
+        return super.toModelDocFilename(toModelName(name));
+    }
+
     @Override
     public String toApiFilename(String name) {
         return underscore(toApiName(name));

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

@@ -293,7 +293,7 @@ public void modelNameTest(String name, String expectedName) {
         final CodegenModel cm = codegen.fromModel(name, model);
 
         Assert.assertEquals(cm.name, name);
-        Assert.assertEquals(cm.classname, expectedName);
+        Assert.assertEquals(cm.classname, codegen.toModelName(expectedName));
     }
 
     @Test(description = "test enum variable names for reserved words")

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

@@ -366,7 +366,7 @@ public static Object[][] primeNumbers() {
             {"sample_name", "SampleName"},
             {"sample__name", "SampleName"},
             {"/sample", "Sample"},
-            {"\\sample", "\\Sample"},
+            {"\\sample", "Sample"},
             {"sample.name", "SampleName"},
             {"_sample", "Sample"},
         };

samples/client/petstore/dart-dio/.openapi-generator/VERSION

@@ -1 +1 @@
-4.2.3-SNAPSHOT
+4.3.0-SNAPSHOT