fix: disableDiscriminatorJsonIgnoreProperties no working in Spring generator (#23640)

Co-authored-by: Krste Nikoloski <Krste.Nikoloski@netcetera.com>

Author: knikolos

modules/openapi-generator/src/main/resources/JavaSpring/typeInfoAnnotation.mustache

@@ -1,11 +1,16 @@
 {{#jackson}}
 {{#discriminator.mappedModels}}
 {{#-first}}
+{{^disableDiscriminatorJsonIgnoreProperties}}
 @JsonIgnoreProperties(
   value = "{{{discriminator.propertyBaseName}}}", // ignore manually set {{{discriminator.propertyBaseName}}}, it will be automatically generated by Jackson during serialization
   allowSetters = true // allows the {{{discriminator.propertyBaseName}}} to be set during deserialization
 )
 @JsonTypeInfo(use = JsonTypeInfo.Id.NAME, include = JsonTypeInfo.As.PROPERTY, property = "{{{discriminator.propertyBaseName}}}", visible = true)
+{{/disableDiscriminatorJsonIgnoreProperties}}
+{{#disableDiscriminatorJsonIgnoreProperties}}
+    @JsonTypeInfo(use = JsonTypeInfo.Id.NAME, include = JsonTypeInfo.As.EXISTING_PROPERTY, property = "{{{discriminator.propertyBaseName}}}", visible = true)
+{{/disableDiscriminatorJsonIgnoreProperties}}
 @JsonSubTypes({
 {{/-first}}
   {{^vendorExtensions.x-discriminator-value}}

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

@@ -7596,4 +7596,20 @@ void oneOf_issue_14769() throws IOException {
                 .isNormalClass()
                 .extendsClass("VehicleDto");
     }
+
+    @Test
+    void disableDiscriminatorJsonIgnorePropertiesIsTrueThenJsonIgnorePropertiesShouldBeNotAdded() throws IOException {
+        final Map<String, File> files = generateFromContract("src/test/resources/3_0/java/issue12777.yaml", SPRING_BOOT,
+            Map.of(DISABLE_DISCRIMINATOR_JSON_IGNORE_PROPERTIES, "true"));
+        JavaFileAssert.assertThat(files.get("BaseConfiguration.java"))
+            .assertTypeAnnotations().doesNotContainWithName("JsonIgnoreProperties");
+    }
+
+    @Test
+    void disableDiscriminatorJsonIgnorePropertiesIsTrueThenJsonIgnorePropertiesShouldBeAdded() throws IOException {
+        final Map<String, File> files = generateFromContract("src/test/resources/3_0/java/issue12777.yaml", SPRING_BOOT,
+            Map.of(DISABLE_DISCRIMINATOR_JSON_IGNORE_PROPERTIES, "false"));
+        JavaFileAssert.assertThat(files.get("BaseConfiguration.java"))
+            .assertTypeAnnotations().containsWithName("JsonIgnoreProperties");
+    }
 }