properly handle duplicate names in vcd

crates/fayalite/tests/sim.rs

@@ -1246,3 +1246,33 @@ fn test_memories3() {
         panic!();
     }
 }
+
+#[hdl_module(outline_generated)]
+pub fn duplicate_names() {
+    #[hdl]
+    let w = wire();
+    connect(w, 5u8);
+    #[hdl]
+    let w = wire();
+    connect(w, 6u8);
+}
+
+#[test]
+fn test_duplicate_names() {
+    let _n = SourceLocation::normalize_files_for_tests();
+    let mut sim = Simulation::new(duplicate_names());
+    let mut writer = RcWriter::default();
+    sim.add_trace_writer(VcdWriterDecls::new(writer.clone()));
+    sim.advance_time(SimDuration::from_micros(1));
+    sim.flush_traces().unwrap();
+    let vcd = String::from_utf8(writer.take()).unwrap();
+    println!("####### VCD:\n{vcd}\n#######");
+    if vcd != include_str!("sim/expected/duplicate_names.vcd") {
+        panic!();
+    }
+    let sim_debug = format!("{sim:#?}");
+    println!("#######\n{sim_debug}\n#######");
+    if sim_debug != include_str!("sim/expected/duplicate_names.txt") {
+        panic!();
+    }
+}