feat: 实现模块引入功能以及测试

src/interpreter/tests.rs

@@ -1626,3 +1626,110 @@ fn error_string_unknown_property() {
     });
     assert!(result.is_err(), "Expected error for unknown string property");
 }
+
+// =========================================================================
+// Module system (require)
+// =========================================================================
+
+#[test]
+fn eval_require_math_module() {
+    let interp = run("let math = require(\"tests/fixtures/math.ast\");");
+    let math = get_var(&interp, "math");
+    match math {
+        Value::Object(obj) => {
+            let obj = obj.borrow();
+            assert!(obj.contains_key("add"), "math should contain 'add'");
+            assert!(obj.contains_key("mul"), "math should contain 'mul'");
+            assert!(obj.contains_key("version"), "math should contain 'version'");
+        }
+        v => panic!("Expected Object, got {:?}", v),
+    }
+}
+
+#[test]
+fn eval_require_call_exported_function() {
+    let interp = run(r#"
+        let math = require("tests/fixtures/math.ast");
+        let result = math.add(10, 32);
+    "#);
+    assert_num(&get_var(&interp, "result"), 42.0);
+}
+
+#[test]
+fn eval_require_cache_returns_same_object() {
+    let interp = run(r#"
+        let a = require("tests/fixtures/math.ast");
+        let b = require("tests/fixtures/math.ast");
+        let same = a == b;
+    "#);
+    assert_bool(&get_var(&interp, "same"), true);
+}
+
+#[test]
+fn eval_require_module_isolation() {
+    // 模块看不到调用者的变量，但模块内部定义可以正常工作
+    let interp = run(r#"
+        let secret = 99;
+        let g = require("tests/fixtures/greet.ast");
+        let msg = g.greet("Aster");
+    "#);
+    match get_var(&interp, "msg") {
+        Value::String(s) => assert_eq!(s, "Hello!"),
+        v => panic!("Expected String, got {:?}", v),
+    }
+}
+
+#[test]
+fn eval_require_module_with_builtins() {
+    // 模块内部可以使用内置函数（因为 builtins_env 是模块 env 的祖先）
+    let interp = run(r#"
+        let m = require("tests/fixtures/math.ast");
+        let r = m.add(5, 7);
+    "#);
+    assert_num(&get_var(&interp, "r"), 12.0);
+}
+
+#[test]
+fn eval_require_error_file_not_found() {
+    let result = std::panic::catch_unwind(|| {
+        run("let x = require(\"nonexistent_file_xyz.ast\");");
+    });
+    assert!(result.is_err(), "Expected error for missing module file");
+}
+
+#[test]
+fn eval_require_error_no_args() {
+    let result = std::panic::catch_unwind(|| {
+        run("let x = require();");
+    });
+    assert!(result.is_err(), "Expected error for require() with no args");
+}
+
+#[test]
+fn eval_require_error_non_string_arg() {
+    let result = std::panic::catch_unwind(|| {
+        run("let x = require(42);");
+    });
+    assert!(result.is_err(), "Expected error for require() with non-string arg");
+}
+
+#[test]
+fn eval_require_error_broken_syntax() {
+    let result = std::panic::catch_unwind(|| {
+        run("let x = require(\"tests/fixtures/broken_syntax.ast\");");
+    });
+    assert!(result.is_err(), "Expected error for module with syntax error");
+}
+
+#[test]
+fn eval_require_empty_module() {
+    // 空模块应该返回空对象
+    let interp = run("let empty = require(\"tests/fixtures/sub/mod.ast\");");
+    match get_var(&interp, "empty") {
+        Value::Object(obj) => {
+            let obj = obj.borrow();
+            assert!(obj.contains_key("sub"), "empty module should contain 'sub'");
+        }
+        v => panic!("Expected Object, got {:?}", v),
+    }
+}