fix: sloppy 模式属性赋值静默 no-op——写失败按写方严格模式分派，内置写路径一律按严格

crates/oxide_vm/tests/builtins_object_tests.rs

@@ -124,8 +124,8 @@ fn object_define_property_rejects_mixed_descriptor() {
 }
 
 #[test]
-fn object_define_property_non_writable_assignment_throws() {
-    let err = match eval("var o={}; Object.defineProperty(o,'x',{value:1}); o.x=2") {
+fn object_define_property_non_writable_assignment_throws_in_strict() {
+    let err = match eval("var o={}; Object.defineProperty(o,'x',{value:1}); (function(){'use strict'; o.x=2})()") {
         Ok(_) => panic!("expected assignment to fail"),
         Err(err) => err,
     };

crates/oxide_vm/tests/member_write_ic_tests.rs

@@ -90,16 +90,18 @@ fn proto_setter_called_both_write_paths() {
     assert_eq!(r, "2:0", "setter 被调 2 次（IC_SET 与 member 各 1），o 无 own 属性");
 }
 
-/// 原型只读 data：两条写路径都按 ordinary_set 抛 TypeError。
+/// 严格模式原型只读 data：两条写路径都按 ordinary_set 抛 TypeError。
 #[test]
-fn readonly_inherited_data_raises() {
+fn readonly_inherited_data_raises_in_strict() {
     let (r, _hits, _misses) = run_once(
         r#"var p = {};
            Object.defineProperty(p, 'x', { value: 1, writable: false });
            var o = Object.create(p);
            var msg = '';
-           try { o.x = 5; } catch (e) { msg = e.message; }
-           try { o.x += 1; } catch (e) { msg += '|' + e.message; }
+           (function() { 'use strict';
+             try { o.x = 5; } catch (e) { msg = e.message; }
+             try { o.x += 1; } catch (e) { msg += '|' + e.message; }
+           })();
            msg"#,
     );
     assert_eq!(
@@ -108,6 +110,21 @@ fn readonly_inherited_data_raises() {
     );
 }
 
+/// sloppy 原型只读 data：两条写路径都静默 no-op（值不变、不抛）。
+#[test]
+fn readonly_inherited_data_silently_fails_in_sloppy() {
+    let (r, _hits, _misses) = run_once(
+        r#"var p = {};
+           Object.defineProperty(p, 'x', { value: 1, writable: false });
+           var o = Object.create(p);
+           var threw = false;
+           try { o.x = 5; } catch (e) { threw = true; }
+           try { o.x += 1; } catch (e) { threw = true; }
+           threw + ':' + o.x + ':' + o.hasOwnProperty('x')"#,
+    );
+    assert_eq!(r, "false:1:false", "sloppy 只读继承属性写静默失败，值保持 1，不创建 own 属性");
+}
+
 /// 写新属性（shape 转换）：快路径建 shape + 写回，循环内同 shape 写全命中。
 #[test]
 fn write_new_prop_then_hit() {

crates/oxide_vm/tests/property_array_fastpath_tests.rs

@@ -89,16 +89,26 @@ fn accessor_getter_and_setter_still_trigger() {
     );
 }
 
-// 非写属性（writable:false）写入：fast path 不命中，走完整协议抛 TypeError。
+// 非写属性（writable:false）写入（严格模式）：fast path 不命中，走完整协议抛 TypeError。
 #[test]
-fn non_writable_index_write_throws() {
+fn non_writable_index_write_throws_in_strict() {
     let r = eval_str(
-        "var a=[1,2,3]; Object.defineProperty(a,0,{writable:false,value:1}); try { a[0]=9; 'no' } catch(e) { e instanceof TypeError ? 'throws' : 'wrong' }"
+        "var a=[1,2,3]; Object.defineProperty(a,0,{writable:false,value:1}); var r='no'; (function(){'use strict'; try { a[0]=9; } catch(e) { r = (e instanceof TypeError ? 'throws' : 'wrong'); } })(); r"
     )
     .unwrap();
     assert_eq!(r, "throws", "expected TypeError, got {r:?}");
 }
 
+// 非写属性（writable:false）写入（sloppy）：静默 no-op，值不变。
+#[test]
+fn non_writable_index_write_silently_fails_in_sloppy() {
+    let r = eval_str(
+        "var a=[1,2,3]; Object.defineProperty(a,0,{writable:false,value:1}); try { a[0]=9; 'no' } catch(e) { 'threw' }; a[0]"
+    )
+    .unwrap();
+    assert_eq!(r, "1", "sloppy 只读元素写应静默 no-op，值保持 1，实际 {r:?}");
+}
+
 // 非规范数字串（前导零）不映射整数键，走字符串键慢路径（不命中 fast path）。
 #[test]
 fn non_canonical_index_string_uses_slow_path() {

crates/oxide_vm/tests/property_write_protection_tests.rs

@@ -33,17 +33,30 @@ fn assert_err_contains(result: Result<JsValue, String>, expected: &str) {
     }
 }
 
-// ── 向不可写自身属性赋值抛 TypeError ──
+// ── 严格模式向不可写自身属性赋值抛 TypeError ──
 #[test]
-fn assign_to_non_writable_throws() {
+fn assign_to_non_writable_throws_in_strict() {
     let result = eval_many(&[
         "var obj = {}",
         "Object.defineProperty(obj, 'x', {value: 1, writable: false})",
-        "obj.x = 2",
+        "(function() { 'use strict'; obj.x = 2 })()",
     ]);
     assert_err_contains(result, "read-only");
 }
 
+// ── sloppy 向不可写自身属性赋值静默失败（值不变、不抛） ──
+#[test]
+fn assign_to_non_writable_silently_fails_in_sloppy() {
+    let r = eval_many(&[
+        "var obj = {}",
+        "Object.defineProperty(obj, 'x', {value: 1, writable: false})",
+        "obj.x = 2",
+        "obj.x",
+    ])
+    .unwrap();
+    assert!(r.is_int() && r.as_int() == 1, "sloppy 只读属性写应静默 no-op，值保持 1，实际 {:?}", r);
+}
+
 // ── 向可写自身属性赋值成功 ──
 #[test]
 fn assign_to_writable_succeeds() {
@@ -57,46 +70,87 @@ fn assign_to_writable_succeeds() {
     assert!(r.is_int() && r.as_int() == 2, "assign to writable should set value to 2, got {:?}", r);
 }
 
-// ── 向原型上不可写的继承属性赋值抛错 ──
+// ── 严格模式向原型上不可写的继承属性赋值抛错 ──
 #[test]
-fn assign_to_inherited_non_writable_throws() {
+fn assign_to_inherited_non_writable_throws_in_strict() {
     let result = eval_many(&[
         "var proto = {}",
         "Object.defineProperty(proto, 'x', {value: 1, writable: false, enumerable: true, configurable: true})",
         "var child = Object.create(proto)",
-        "child.x = 2",
+        "(function() { 'use strict'; child.x = 2 })()",
     ]);
     assert_err_contains(result, "read-only");
 }
 
-// ── 原型属性不可写但子对象无自有属性时，赋值会在子对象上创建自有属性
-// ponytail: spec allows shadowing when proto prop is configurable; engine doesn't yet.
-// 引擎对不可写原型属性正确抛错；完整遮蔽作为后续工作。
+// ── 继承只读数据属性：sloppy 赋值静默失败，不创建自有属性（不遮蔽） ──
 #[test]
-fn assign_non_writable_proto_configurable_prop_throws() {
+fn assign_to_inherited_non_writable_silently_fails_in_sloppy() {
+    let (_vm, r) = eval_keep_vm(
+        &[
+            "var proto = {}",
+            "Object.defineProperty(proto, 'x', {value: 1, writable: false, enumerable: true, configurable: true})",
+            "var child = Object.create(proto)",
+            "child.x = 99",
+            "[child.x, child.hasOwnProperty('x')]",
+        ]
+        .join("; "),
+    )
+    .unwrap();
+    let arr = unsafe { &*r.as_js_object_ptr() };
+    assert!(
+        arr.get_prop_at(0).is_int() && arr.get_prop_at(0).as_int() == 1,
+        "sloppy 写只读继承属性应静默 no-op，值保持 1"
+    );
+    assert!(
+        arr.get_prop_at(1).is_bool() && !arr.get_prop_at(1).as_bool(),
+        "静默失败不得在子对象上创建自有属性"
+    );
+}
+
+// ── 严格模式：原型只读可配置属性赋值抛错（不可写数据属性不可遮蔽） ──
+#[test]
+fn assign_non_writable_proto_configurable_prop_throws_in_strict() {
     let result = eval_many(&[
         "var proto = {}",
         "Object.defineProperty(proto, 'x', {value: 1, writable: false, enumerable: true, configurable: true})",
         "var child = Object.create(proto)",
-        "child.x = 99",
+        "(function() { 'use strict'; child.x = 99 })()",
     ]);
     assert_err_contains(result, "read-only");
 }
 
-// ── Object.freeze 后写已有属性抛 TypeError ──
+// ── 严格模式 Object.freeze 后写已有属性抛 TypeError ──
 #[test]
-fn frozen_write_existing_prop_throws() {
-    let result = eval_many(&["var o = Object.freeze({a: 1})", "o.a = 2"]);
+fn frozen_write_existing_prop_throws_in_strict() {
+    let result = eval_many(&["var o = Object.freeze({a: 1})", "(function() { 'use strict'; o.a = 2 })()"]);
     assert_err_contains(result, "read-only");
 }
 
-// ── Object.freeze 后写新属性抛 TypeError ──
+// ── sloppy Object.freeze 后写已有属性静默失败 ──
 #[test]
-fn frozen_write_new_prop_throws() {
-    let result = eval_many(&["var o = Object.freeze({a: 1})", "o.b = 2"]);
+fn frozen_write_existing_prop_silently_fails_in_sloppy() {
+    let r = eval_many(&["var o = Object.freeze({a: 1})", "o.a = 2", "o.a"]).unwrap();
+    assert!(r.is_int() && r.as_int() == 1, "sloppy 冻结对象写应静默 no-op，值保持 1，实际 {:?}", r);
+}
+
+// ── 严格模式 Object.freeze 后写新属性抛 TypeError ──
+#[test]
+fn frozen_write_new_prop_throws_in_strict() {
+    let result = eval_many(&["var o = Object.freeze({a: 1})", "(function() { 'use strict'; o.b = 2 })()"]);
     assert_err_contains(result, "not extensible");
 }
 
+// ── sloppy Object.freeze 后写新属性静默失败（属性不创建） ──
+#[test]
+fn frozen_write_new_prop_silently_fails_in_sloppy() {
+    let r = eval_many(&["var o = Object.freeze({a: 1})", "o.b = 2", "o.b === undefined"]).unwrap();
+    assert!(
+        r.is_bool() && r.as_bool(),
+        "sloppy 冻结对象写新属性应静默 no-op，属性不创建，实际 {:?}",
+        r
+    );
+}
+
 // ── Object.freeze 后 defineProperty 抛 TypeError ──
 #[test]
 fn frozen_define_property_throws() {
@@ -104,13 +158,14 @@ fn frozen_define_property_throws() {
     assert_err_contains(result, "not extensible");
 }
 
-// ── Object.seal 后写新属性抛错、删属性返回 false、改值生效 ──
+// ── 严格模式 Object.seal 后写新属性抛错、删属性返回 false、改值生效 ──
 #[test]
 fn sealed_semantics() {
     let (_vm, r) = eval_keep_vm(
         &[
             "var o = Object.seal({a: 1})",
-            "var new_throws = false; try { o.b = 2 } catch (e) { new_throws = true }",
+            "var new_throws = false",
+            "(function() { 'use strict'; try { o.b = 2 } catch (e) { new_throws = true } })()",
             "var del = delete o.a",
             "o.a = 5",
             "[new_throws, del, o.a, o.hasOwnProperty('a')]",
@@ -121,30 +176,30 @@ fn sealed_semantics() {
     let arr = unsafe { &*r.as_js_object_ptr() };
     assert!(
         arr.get_prop_at(0).is_bool() && arr.get_prop_at(0).as_bool(),
-        "new prop write should throw"
+        "strict new prop write should throw"
     );
     assert!(arr.get_prop_at(1).is_bool() && !arr.get_prop_at(1).as_bool(), "delete should be false");
     assert!(arr.get_prop_at(2).is_int() && arr.get_prop_at(2).as_int() == 5, "value write should work");
     assert!(arr.get_prop_at(3).is_bool() && arr.get_prop_at(3).as_bool(), "prop should remain own");
 }
 
-// ── Object.preventExtensions 后新属性不生效（sloppy 抛错），已有属性可写 ──
+// ── Object.preventExtensions 后新属性写静默失效（sloppy），已有属性可写 ──
 #[test]
 fn prevent_extensions_semantics() {
     let (_vm, r) = eval_keep_vm(
         &[
             "var o = Object.preventExtensions({a: 1})",
-            "var new_throws = false; try { o.b = 3 } catch (e) { new_throws = true }",
+            "var new_threw = false; try { o.b = 3 } catch (e) { new_threw = true }",
             "o.a = 2",
-            "[new_throws, o.a, o.b === undefined]",
+            "[new_threw, o.a, o.b === undefined]",
         ]
         .join("; "),
     )
     .unwrap();
     let arr = unsafe { &*r.as_js_object_ptr() };
     assert!(
-        arr.get_prop_at(0).is_bool() && arr.get_prop_at(0).as_bool(),
-        "new prop write should throw"
+        arr.get_prop_at(0).is_bool() && !arr.get_prop_at(0).as_bool(),
+        "sloppy new prop write should silently fail"
     );
     assert!(
         arr.get_prop_at(1).is_int() && arr.get_prop_at(1).as_int() == 2,
@@ -153,15 +208,15 @@ fn prevent_extensions_semantics() {
     assert!(arr.get_prop_at(2).is_bool() && arr.get_prop_at(2).as_bool(), "new prop should be absent");
 }
 
-// ── Object.freeze 数组：元素写与 length 收缩均被拦截 ──
+// ── 严格模式 Object.freeze 数组：元素写与 length 收缩均抛错 ──
 #[test]
-fn frozen_array_write_and_length_throws() {
+fn frozen_array_write_and_length_throws_in_strict() {
     let (_vm, r) = eval_keep_vm(
         &[
             "var a = Object.freeze([1, 2])",
             "var e1 = false, e2 = false",
-            "try { a[0] = 9 } catch (e) { e1 = true }",
-            "try { a.length = 0 } catch (e) { e2 = true }",
+            "(function() { 'use strict'; try { a[0] = 9 } catch (e) { e1 = true } })()",
+            "(function() { 'use strict'; try { a.length = 0 } catch (e) { e2 = true } })()",
             "[e1, e2, a[0], a.length, Object.getOwnPropertyDescriptor(a, '0').writable]",
         ]
         .join("; "),
@@ -178,6 +233,27 @@ fn frozen_array_write_and_length_throws() {
     );
 }
 
+// ── sloppy Object.freeze 数组：元素写静默失败（length 冻结检查仍抛错） ──
+#[test]
+fn frozen_array_element_write_silently_fails_in_sloppy() {
+    let (_vm, r) = eval_keep_vm(
+        &[
+            "var a = Object.freeze([1, 2])",
+            "var e1 = false",
+            "try { a[0] = 9 } catch (e) { e1 = true }",
+            "[e1, a[0]]",
+        ]
+        .join("; "),
+    )
+    .unwrap();
+    let arr = unsafe { &*r.as_js_object_ptr() };
+    assert!(
+        arr.get_prop_at(0).is_bool() && !arr.get_prop_at(0).as_bool(),
+        "sloppy 冻结数组元素写应静默 no-op"
+    );
+    assert!(arr.get_prop_at(1).is_int() && arr.get_prop_at(1).as_int() == 1, "element value unchanged");
+}
+
 // ── isFrozen/isSealed：手动 defineProperty 全部冻结（未调 freeze）也应判 true ──
 #[test]
 fn is_frozen_manual_define_props() {
@@ -212,19 +288,40 @@ fn reflect_ops_on_frozen_return_false() {
     }
 }
 
-// ── freeze/seal 后 IC 直写路径失效：循环写仍被拦截 ──
+// ── 严格模式 freeze 后 IC 直写路径失效：循环写仍被拦截 ──
 #[test]
-fn frozen_ic_path_still_blocks_write() {
+fn frozen_ic_path_still_blocks_write_in_strict() {
     let r = eval_many(&[
         "var o = Object.freeze({a: 1})",
         "var threw = false",
-        "for (var i = 0; i < 3; i++) { try { o.a = i } catch (e) { threw = true } }",
+        "(function() { 'use strict'; for (var i = 0; i < 3; i++) { try { o.a = i } catch (e) { threw = true } } })()",
         "threw",
     ])
     .unwrap();
     assert!(r.is_bool() && r.as_bool(), "IC path should still throw on frozen write");
 }
 
+// ── sloppy freeze 后循环写静默失效（值不变、不抛） ──
+#[test]
+fn frozen_ic_path_silently_fails_in_sloppy() {
+    let (_vm, r) = eval_keep_vm(
+        &[
+            "var o = Object.freeze({a: 1})",
+            "var threw = false",
+            "for (var i = 0; i < 3; i++) { try { o.a = i } catch (e) { threw = true } }",
+            "[threw, o.a]",
+        ]
+        .join("; "),
+    )
+    .unwrap();
+    let arr = unsafe { &*r.as_js_object_ptr() };
+    assert!(
+        arr.get_prop_at(0).is_bool() && !arr.get_prop_at(0).as_bool(),
+        "sloppy frozen write should silently fail"
+    );
+    assert!(arr.get_prop_at(1).is_int() && arr.get_prop_at(1).as_int() == 1, "value unchanged");
+}
+
 // ── sealed 对象 IC 路径：已有属性写正常 ──
 #[test]
 fn sealed_ic_path_allows_existing_write() {

crates/oxide_vm/tests/sloppy_assignment_silent_tests.rs

@@ -0,0 +1,196 @@
+//! sloppy 模式赋值静默失败语义测试：ordinary_set 失败分支（自身/继承只读数据、
+//! 无 setter 访问器、不可扩展新属性）在 sloppy 静默 no-op，严格模式抛 TypeError。
+//! 覆盖脚本顶层（`top_level_strict`）、函数级（帧 `strict`）与内联内置回调
+//! （forEach 等，`inline_strict` + 帧基线）三种执行上下文。
+
+use oxide_compiler::compiler::Compiler;
+use oxide_types::value::JsValue;
+use oxide_vm::vm::Vm;
+
+fn eval(source: &str) -> Result<JsValue, String> {
+    let allocator = oxide_parser::Allocator::default();
+    let program = oxide_parser::parse(&allocator, source).map_err(|e| format!("Parse error: {:?}", e))?;
+    let module = Compiler::new().compile(&program).map_err(|e| format!("Compile error: {}", e))?;
+    let mut vm = Vm::new();
+    vm.run(&module)
+}
+
+fn eval_many(lines: &[&str]) -> Result<JsValue, String> {
+    eval(&lines.join("; "))
+}
+
+fn assert_err_contains(result: Result<JsValue, String>, expected: &str) {
+    match result {
+        Ok(_) => panic!("expected error containing '{}', got Ok", expected),
+        Err(e) => assert!(e.contains(expected), "expected error containing '{}', got: {}", expected, e),
+    }
+}
+
+/// 求值并把结果按字符串提取（`JsValue` Display 不携带字符串内容）。
+fn eval_str(source: &str) -> String {
+    let allocator = oxide_parser::Allocator::default();
+    let program = oxide_parser::parse(&allocator, source).expect("parse");
+    let module = Compiler::new().compile(&program).expect("compile");
+    let mut vm = Vm::new();
+    let result = vm.run(&module).expect("run");
+    vm.lookup_str(result).unwrap_or_else(|| format!("{result}"))
+}
+
+// ── sloppy 脚本顶层：无 setter 访问器赋值静默 no-op（值不变、不抛） ──
+#[test]
+fn sloppy_script_top_level_accessor_no_setter_silently_fails() {
+    let r = eval_many(&["var o = { get h() { return 1 } }", "o.h = 2", "o.h"]).unwrap();
+    assert!(
+        r.is_int() && r.as_int() == 1,
+        "sloppy 无 setter 访问器写应静默 no-op，值保持 1，实际 {:?}",
+        r
+    );
+}
+
+// ── 严格脚本（顶层指令）：无 setter 访问器赋值抛 TypeError ──
+#[test]
+fn strict_script_top_level_accessor_no_setter_throws() {
+    let result = eval("'use strict'; var o = { get h() { return 1 } }; o.h = 2");
+    assert_err_contains(result, "no setter");
+}
+
+// ── sloppy 脚本顶层：只读自身属性赋值静默失败 ──
+#[test]
+fn sloppy_script_top_level_readonly_silently_fails() {
+    let r = eval("var o = {}; Object.defineProperty(o, 'x', {value: 1, writable: false}); o.x = 2; o.x").unwrap();
+    assert!(r.is_int() && r.as_int() == 1, "sloppy 只读属性写应静默 no-op，值保持 1，实际 {:?}", r);
+}
+
+// ── 严格脚本（顶层指令）：只读自身属性赋值抛 TypeError ──
+#[test]
+fn strict_script_top_level_readonly_throws() {
+    let result = eval("'use strict'; var o = {}; Object.defineProperty(o, 'x', {value: 1, writable: false}); o.x = 2");
+    assert_err_contains(result, "read-only");
+}
+
+// ── sloppy 函数级（非严格函数）：不可扩展对象写新属性静默失败 ──
+#[test]
+fn sloppy_function_write_new_prop_on_non_extensible_silently_fails() {
+    let r = eval_many(&[
+        "var o = Object.preventExtensions({})",
+        "function w() { o.n = 3 }",
+        "w()",
+        "o.n === undefined",
+    ])
+    .unwrap();
+    assert!(
+        r.is_bool() && r.as_bool(),
+        "sloppy 函数写不可扩展对象新属性应静默 no-op，属性不创建，实际 {:?}",
+        r
+    );
+}
+
+// ── 严格函数：不可扩展对象写新属性抛 TypeError ──
+#[test]
+fn strict_function_write_new_prop_on_non_extensible_throws() {
+    let result = eval_many(&["var o = Object.preventExtensions({})", "(function() { 'use strict'; o.n = 3 })()"]);
+    assert_err_contains(result, "not extensible");
+}
+
+// ── 继承只读数据属性：sloppy 赋值静默失败且不创建自有属性 ──
+#[test]
+fn sloppy_inherited_readonly_silently_fails_without_shadow() {
+    let s = eval_str(
+        "var p = {}; Object.defineProperty(p, 'x', {value: 1, writable: false, configurable: true}); \
+         var c = Object.create(p); c.x = 9; c.x + ':' + c.hasOwnProperty('x')",
+    );
+    assert_eq!(s, "1:false", "sloppy 只读继承属性写应静默 no-op，值保持 1 且不遮蔽");
+}
+
+// ── 内联回调（forEach）：sloppy 顶层 + sloppy 回调，只读属性写静默失败 ──
+#[test]
+fn sloppy_inline_callback_write_to_readonly_silently_fails() {
+    let r = eval_many(&[
+        "var o = {}",
+        "Object.defineProperty(o, 'p', {value: 0, writable: false, configurable: true})",
+        "[1].forEach(function() { o.p = 1 })",
+        "o.p",
+    ])
+    .unwrap();
+    assert!(r.is_int() && r.as_int() == 0, "sloppy 内联回调内只读属性写应静默 no-op，实际 {:?}", r);
+}
+
+// ── 内联回调：严格函数上下文（回调继承严格），只读属性写抛 TypeError ──
+#[test]
+fn strict_inline_callback_write_to_readonly_throws() {
+    let r = eval_many(&[
+        "var o = {}",
+        "Object.defineProperty(o, 'p', {value: 0, writable: false, configurable: true})",
+        "var threw = false",
+        "(function() { 'use strict'; [1].forEach(function() { try { o.p = 1 } catch (e) { threw = true } }) })()",
+        "threw",
+    ])
+    .unwrap();
+    assert!(r.is_bool() && r.as_bool(), "严格内联回调内只读属性写应抛 TypeError，实际 {:?}", r);
+}
+
+// ── 嵌套内联：sloppy 回调内调用严格动态函数，写只读属性抛 TypeError
+//    （严格性随内联快照逐层保存/恢复，内层取内层目标） ──
+#[test]
+fn nested_inline_strict_target_write_throws() {
+    let r = eval_many(&[
+        "var o = {}",
+        "Object.defineProperty(o, 'p', {value: 0, writable: false, configurable: true})",
+        "var strictWrite = new Function('o', \"'use strict'; o.p = 1\")",
+        "var threw = false",
+        "[1].forEach(function() { try { strictWrite(o) } catch (e) { threw = true } })",
+        "threw",
+    ])
+    .unwrap();
+    assert!(
+        r.is_bool() && r.as_bool(),
+        "嵌套内联中严格目标函数的只读属性写应抛 TypeError，实际 {:?}",
+        r
+    );
+}
+
+// ── 嵌套内联反向：严格回调内调用 sloppy 动态函数，写只读属性静默失败 ──
+#[test]
+fn nested_inline_sloppy_target_write_silently_fails() {
+    let r = eval_many(&[
+        "var o = {}",
+        "Object.defineProperty(o, 'p', {value: 0, writable: false, configurable: true})",
+        "var sloppyWrite = new Function('o', 'o.p = 1')",
+        "(function() { 'use strict'; [1].forEach(function() { sloppyWrite(o) }) })()",
+        "o.p",
+    ])
+    .unwrap();
+    assert!(
+        r.is_int() && r.as_int() == 0,
+        "嵌套内联中 sloppy 目标函数的只读属性写应静默 no-op，实际 {:?}",
+        r
+    );
+}
+
+// ── 链式赋值中间对象只读（冻结）：sloppy 对中间对象写新属性静默失败 ──
+#[test]
+fn sloppy_chained_write_through_readonly_middle_silently_fails() {
+    let s = eval_str(
+        "var holder = Object.freeze({}); var o = { b: holder }; o.b.c = 1; \
+         Object.keys(o.b).length + ':' + (o.b.c === undefined)",
+    );
+    assert_eq!(s, "0:true", "sloppy 链式中间冻结对象写新属性应静默 no-op，c 不创建");
+}
+
+// ── 链式赋值中间对象只读（冻结）：严格模式抛 TypeError ──
+#[test]
+fn strict_chained_write_through_readonly_middle_throws() {
+    let result = eval_many(&[
+        "var holder = Object.freeze({})",
+        "var o = { b: holder }",
+        "(function() { 'use strict'; o.b.c = 1 })()",
+    ]);
+    assert_err_contains(result, "not extensible");
+}
+
+// ── 顶层脚本 sloppy 赋值只读全局属性（undefined）不抛错 ──
+#[test]
+fn sloppy_top_level_assign_to_readonly_global_no_throw() {
+    let r = eval_many(&["undefined = 1", "typeof undefined"]).unwrap();
+    assert!(r.is_string(), "sloppy 顶层对只读全局属性赋值不得抛错，实际 {:?}", r);
+}