Emit InnerClasses on enum variants too, not just the main enum class, to enable correct processing of enums in IntelliJ.

Author: IntegralPilot

java-linker/src/main.rs

@@ -766,14 +766,15 @@ fn run_r8_optimizer(
         .arg("--lib")
         .arg(java_runtime_lib_path)
         .arg("--classfile");
-
     // Add all the *other* input JARs as libraries
     for lib_path in library_jar_paths {
         cmd.arg("--classpath").arg(lib_path);
     }
 
     if release_mode {
         cmd.arg("--release"); // Add release mode flag if specified
+    } else {
+        cmd.arg("--debug"); // Add debug mode flag if not release
     }
 
     // Add the program input JAR (containing app classes) last

src/lower2.rs

@@ -173,10 +173,23 @@ pub fn oomir_to_jvm_bytecode(
                 interfaces,
             } => {
                 let mut subclasses = Vec::new();
+                let mut nest_host = None;
+                // does our class name contain '$'?
+                let mut potential_nest_host = None;
+                if dt_name_oomir.contains('$') {
+                    // strip everything after the last '$', including $
+                    let last_dollar_index = dt_name_oomir.rfind('$').unwrap();
+                    potential_nest_host = Some(dt_name_oomir[..last_dollar_index].to_string());
+                }
                 for (other_dt_name, _) in &module.data_types {
                     if other_dt_name.starts_with(&format!("{}$", dt_name_oomir)) {
                         subclasses.push(other_dt_name.clone());
                     }
+                    if let Some(potential_nest_host) = &potential_nest_host {
+                        if other_dt_name == potential_nest_host {
+                            nest_host = Some(potential_nest_host.clone());
+                        }
+                    }
                 }
                 // Create and serialize the class file for this data type
                 let dt_bytecode = create_data_type_classfile_for_class(
@@ -188,6 +201,7 @@ pub fn oomir_to_jvm_bytecode(
                     interfaces.clone(),
                     &module,
                     subclasses,
+                    nest_host,
                 )?;
                 generated_classes.insert(dt_name_oomir.clone(), dt_bytecode);
             }

src/lower2/jvm_gen.rs

@@ -92,6 +92,7 @@ pub(super) fn create_data_type_classfile_for_class(
     implements_interfaces: Vec<String>,
     module: &oomir::Module,
     subclasses: Vec<String>,
+    nest_host: Option<String>,
 ) -> jvm::Result<Vec<u8>> {
     let mut cp = ConstantPool::default();
 
@@ -246,7 +247,7 @@ pub(super) fn create_data_type_classfile_for_class(
     }
 
     // --- Add InnerClasses Attribute (for nested/member classes) ---
-    if !subclasses.is_empty() {
+    if !subclasses.is_empty() || nest_host.is_some() {
         let mut inner_classes_vec: Vec<InnerClass> = Vec::with_capacity(subclasses.len());
 
         for subclass_name in &subclasses {
@@ -283,6 +284,26 @@ pub(super) fn create_data_type_classfile_for_class(
             });
         }
 
+        // If this class has a nest host, add it as well
+        // make it like [us]=class Host$[us] of class Host
+        if let Some(nest_host_name) = nest_host {
+            let class_info_index = class_file.constant_pool.add_class(class_name_jvm)?;
+            let outer_class_info_index = class_file.constant_pool.add_class(&nest_host_name)?;
+            let name_index =  class_file
+                    .constant_pool
+                    .add_utf8(class_name_jvm
+                        .rsplit('$')
+                        .next()
+                        .unwrap_or(class_name_jvm))?;
+            let access_flags = NestedClassAccessFlags::PUBLIC | NestedClassAccessFlags::STATIC;
+            inner_classes_vec.push(InnerClass {
+                class_info_index,
+                outer_class_info_index,
+                name_index,
+                access_flags,
+            });
+        }
+
         let inner_classes_attr_name_index = class_file.constant_pool.add_utf8("InnerClasses")?;
         class_file.attributes.push(Attribute::InnerClasses {
             name_index: inner_classes_attr_name_index,