Tests(MIR): add extern_call console.log lowering test and verbose MIR dump assertion.

src/mir/mod.rs

@@ -187,6 +187,26 @@ mod tests {
         assert!(has_typeop, "Expected TypeOp lowering for print(obj.is(...))");
     }
 
+    #[test]
+    fn test_lowering_extern_console_log() {
+        // Build AST: console.log("hi") → ExternCall env.console.log
+        let ast = ASTNode::Expression {
+            expr: Box::new(ASTNode::MethodCall {
+                object: Box::new(ASTNode::Variable { name: "console".to_string(), span: crate::ast::Span::unknown() }),
+                method: "log".to_string(),
+                arguments: vec![ ASTNode::Literal { value: LiteralValue::String("hi".to_string()), span: crate::ast::Span::unknown() } ],
+                span: crate::ast::Span::unknown(),
+            }),
+            span: crate::ast::Span::unknown(),
+        };
+
+        let mut compiler = MirCompiler::new();
+        let result = compiler.compile(ast).expect("compile should succeed");
+        let dump = MirPrinter::verbose().print_module(&result.module);
+
+        assert!(dump.contains("extern_call env.console.log"), "Expected extern_call env.console.log in MIR dump. Got:\n{}", dump);
+    }
+    
     #[test]
     fn test_throw_compilation() {
         let mut compiler = MirCompiler::new();