fix: kotlin multiplatform inline enum toString uses enum value instead of constant

modules/openapi-generator/src/main/resources/kotlin-client/data_class.mustache

@@ -176,6 +176,9 @@ import {{packageName}}.infrastructure.ITransformForStorage
         {{/multiplatform}}
     {{/enumVars}}
     {{/allowableValues}}
+    {{#multiplatform}}
+        override fun toString(): kotlin.String = value{{^isString}}.toString(){{/isString}}
+    {{/multiplatform}}
     }
     {{#kotlinx_serialization}}
     {{#enumUnknownDefaultCase}}

modules/openapi-generator/src/main/resources/kotlin-client/libraries/multiplatform/api.mustache

@@ -47,6 +47,7 @@ import kotlinx.serialization.encoding.*
         @SerialName(value = {{^isString}}"{{/isString}}{{{value}}}{{^isString}}"{{/isString}})
         {{&name}}({{{value}}}){{^-last}},{{/-last}}{{#-last}};{{/-last}}
         {{/enumVars}}{{/allowableValues}}
+        override fun toString(): kotlin.String = value{{^isString}}.toString(){{/isString}}
     }
 
     {{/isEnum}}

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

@@ -1064,6 +1064,39 @@ public void testMultiplatformInlineEnumDropsUnknownDefaultCase() throws IOExcept
         TestUtils.assertFileContains(apiKt, "ONE(\"1\");");
     }
 
+    @Test
+    public void testMultiplatformEnumWithCustomVariableNamesOverridesToString() throws IOException {
+        File output = Files.createTempDirectory("test").toFile();
+        output.deleteOnExit();
+
+        final CodegenConfigurator configurator = new CodegenConfigurator()
+                .setGeneratorName(KOTLIN_GENERATOR)
+                .setLibrary("multiplatform")
+                .setAdditionalProperties(new HashMap<>() {{
+                    put(CodegenConstants.SERIALIZATION_LIBRARY, "jackson");
+                    put(CodegenConstants.MODEL_PACKAGE, "model");
+                    put("dateLibrary", "kotlinx-datetime");
+                }})
+                .setInputSpec("src/test/resources/3_0/kotlin/multiplatform-inline-query-enum.yaml")
+                .setOutputDir(output.getAbsolutePath().replace("\\", "/"));
+
+        final ClientOptInput clientOptInput = configurator.toClientOptInput();
+        DefaultGenerator generator = new DefaultGenerator();
+
+        generator.opts(clientOptInput).generate();
+
+        final Path definedEnumKt = Paths.get(output + "/src/commonMain/kotlin/model/ApiError.kt");
+        final Path inlineEnumKt = Paths.get(output + "/src/commonMain/kotlin/model/AllowFoo.kt");
+        final Path headerEnumKt = Paths.get(output + "/src/commonMain/kotlin/org/openapitools/client/apis/DefaultApi.kt");
+
+        TestUtils.assertFileContains(definedEnumKt, "override fun toString(): kotlin.String = value.toString()");
+        TestUtils.assertFileContains(definedEnumKt, "@SerialName(value = \"100\") ERROR(100);");
+        TestUtils.assertFileContains(inlineEnumKt, "override fun toString(): kotlin.String = value");
+        TestUtils.assertFileContains(inlineEnumKt, "ALLOW(\"1\");");
+        TestUtils.assertFileContains(headerEnumKt, "override fun toString(): kotlin.String = value");
+        TestUtils.assertFileContains(headerEnumKt, "ALLOW(\"1\");");
+    }
+
     @Test(description = "convert an empty model to object")
     public void emptyModelKotlinxSerializationTest() throws IOException {
         final Schema<?> schema = new ObjectSchema()

samples/client/petstore/kotlin-multiplatform-kotlinx-datetime/src/commonMain/kotlin/org/openapitools/client/apis/PetApi.kt

@@ -137,6 +137,7 @@ open class PetApi : ApiClient {
         @SerialName(value = "sold")
         sold("sold");
 
+        override fun toString(): kotlin.String = value.toString()
     }
 
     /**

samples/client/petstore/kotlin-multiplatform-kotlinx-datetime/src/commonMain/kotlin/org/openapitools/client/models/Order.kt

@@ -67,6 +67,7 @@ data class Order (
         @SerialName(value = "placed") placed("placed"),
         @SerialName(value = "approved") approved("approved"),
         @SerialName(value = "delivered") delivered("delivered");
+        override fun toString(): kotlin.String = value
     }
 
 }

samples/client/petstore/kotlin-multiplatform-kotlinx-datetime/src/commonMain/kotlin/org/openapitools/client/models/Pet.kt

@@ -69,6 +69,7 @@ data class Pet (
         @SerialName(value = "available") available("available"),
         @SerialName(value = "pending") pending("pending"),
         @SerialName(value = "sold") sold("sold");
+        override fun toString(): kotlin.String = value
     }
 
 }

samples/client/petstore/kotlin-multiplatform/src/commonMain/kotlin/org/openapitools/client/apis/PetApi.kt

@@ -137,6 +137,7 @@ open class PetApi : ApiClient {
         @SerialName(value = "sold")
         sold("sold");
 
+        override fun toString(): kotlin.String = value.toString()
     }
 
     /**

samples/client/petstore/kotlin-multiplatform/src/commonMain/kotlin/org/openapitools/client/models/Order.kt

@@ -67,6 +67,7 @@ data class Order (
         @SerialName(value = "placed") placed("placed"),
         @SerialName(value = "approved") approved("approved"),
         @SerialName(value = "delivered") delivered("delivered");
+        override fun toString(): kotlin.String = value
     }
 
 }

samples/client/petstore/kotlin-multiplatform/src/commonMain/kotlin/org/openapitools/client/models/Pet.kt

@@ -69,6 +69,7 @@ data class Pet (
         @SerialName(value = "available") available("available"),
         @SerialName(value = "pending") pending("pending"),
         @SerialName(value = "sold") sold("sold");
+        override fun toString(): kotlin.String = value
     }
 
 }