fix: 块内函数声明预声明支持（Annex B 块级绑定）
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@@ -405,6 +405,87 @@ impl Emitter {
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}
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}
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/// 预声明当前块直接子树中的函数声明（ES2015 块级绑定，kind=Let 落当前块），
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/// 使块内声明点之前的引用在编译期可见。递归进入嵌套块时压/弹作用域，
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/// 与 emit 阶段嵌套块 push_scope 的时机对齐。
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///
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/// # 边界与前提
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/// - 只处理块内函数声明；switch 不推 scope（其 case 内函数声明随 switch
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/// 作用域修复一并处理）；export 声明不可能出现在块内。
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/// - 与 lexical 预声明的顺序：本函数在前，`{ let g; function g(){} }` 时
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/// lexical 的 `declare_predeclared` 命中已存在的函数绑定自然报重复声明错，
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/// 避免函数预声明被 lexical 占位静默覆盖而破坏 let 的 TDZ。
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/// - var 与函数同名（`{ var g; function g(){} }`）：var 落函数作用域、
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/// 函数落当前块，不同 scope 互不冲突。
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pub(crate) fn predeclare_block_function_declarations(&self, statements: &[Statement], ctx: &mut CompileCtx) {
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for statement in statements {
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match statement {
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Statement::FunctionDeclaration(f) => {
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let Some(identifier) = &f.id else {
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continue;
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};
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let reg = ctx.alloc_reg();
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let _ = ctx.declare_initialized(identifier.name.as_str(), reg, VariableDeclarationKind::Let, false);
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}
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Statement::BlockStatement(bs) => {
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ctx.push_scope();
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self.predeclare_block_function_declarations(&bs.body, ctx);
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ctx.pop_scope();
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}
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Statement::IfStatement(is) => {
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self.predeclare_block_function_declarations(std::slice::from_ref(&is.consequent), ctx);
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if let Some(alt) = &is.alternate {
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self.predeclare_block_function_declarations(std::slice::from_ref(alt), ctx);
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}
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}
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Statement::WhileStatement(wh) => {
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self.predeclare_block_function_declarations(std::slice::from_ref(&wh.body), ctx);
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}
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Statement::DoWhileStatement(dw) => {
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self.predeclare_block_function_declarations(std::slice::from_ref(&dw.body), ctx);
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}
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Statement::ForStatement(fs) => {
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// 循环推独立作用域（头声明所在），函数声明落该作用域与 emit 对齐。
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ctx.push_scope();
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self.predeclare_block_function_declarations(std::slice::from_ref(&fs.body), ctx);
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ctx.pop_scope();
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}
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Statement::ForInStatement(fi) => {
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ctx.push_scope();
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self.predeclare_block_function_declarations(std::slice::from_ref(&fi.body), ctx);
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ctx.pop_scope();
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}
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Statement::ForOfStatement(fo) => {
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ctx.push_scope();
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self.predeclare_block_function_declarations(std::slice::from_ref(&fo.body), ctx);
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ctx.pop_scope();
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}
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Statement::TryStatement(ts) => {
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ctx.push_scope();
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self.predeclare_block_function_declarations(&ts.block.body, ctx);
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ctx.pop_scope();
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if let Some(handler) = &ts.handler {
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ctx.push_scope();
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self.predeclare_block_function_declarations(&handler.body.body, ctx);
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ctx.pop_scope();
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}
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if let Some(finalizer) = &ts.finalizer {
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ctx.push_scope();
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self.predeclare_block_function_declarations(&finalizer.body, ctx);
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ctx.pop_scope();
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}
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}
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Statement::LabeledStatement(ls) => {
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self.predeclare_block_function_declarations(std::slice::from_ref(&ls.body), ctx);
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}
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Statement::WithStatement(ws) => {
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self.predeclare_block_function_declarations(std::slice::from_ref(&ws.body), ctx);
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}
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_ => {}
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}
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}
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}
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/// 预声明当前作用域直接子语句中的 `let`/`const`/`class` 绑定（未初始化，
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/// 建立 TDZ 占位）。使声明点之前的读取在编译期可分辨为 TDZ 而非隐式全局，
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/// 声明点复用预登记槽位。
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@@ -9,6 +9,9 @@ impl Emitter {
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return Ok(None);
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};
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ctx.push_scope();
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// 函数预声明先于 lexical：`{ let g; function g(){} }` 时 lexical 的预声明
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// 命中已存在的函数绑定自然报重复声明错，不被静默覆盖破坏 TDZ。
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self.predeclare_block_function_declarations(&block.body, ctx);
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self.predeclare_lexical_declarations(&block.body, ctx);
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let mut r = None;
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for s in &block.body {
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@@ -0,0 +1,82 @@
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//! 块内函数声明：块级绑定预声明后，声明点前后引用均可编译并执行。
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//!
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//! 覆盖：普通块内函数、块内后续调用、提前调用（阶段 1 现状）、与 let 同名冲突、
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//! 捕获路径、嵌套块作用域隔离、重复声明（Annex B 最后生效）、单语句块体。
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use oxide_compiler::compiler::Compiler;
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use oxide_types::value::JsValue;
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use oxide_vm::vm::Vm;
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fn eval(source: &str) -> Result<JsValue, String> {
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let allocator = oxide_parser::Allocator::default();
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let program = oxide_parser::parse(&allocator, source).map_err(|e| format!("Parse: {:?}", e))?;
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let module = Compiler::new().compile(&program).map_err(|e| format!("Compile: {}", e))?;
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let mut vm = Vm::new();
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vm.run(&module)
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}
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#[test]
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fn block_function_decl_compiles_and_runs() {
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// 块内函数声明可编译执行，无返回值。
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let result = eval("{ function g(){} }").unwrap();
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assert!(result.is_undefined());
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}
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#[test]
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fn block_function_decl_call_after_decl() {
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// 块内声明点之后调用：正常返回函数值。
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let result = eval("{ function g(){return 1;} g(); }").unwrap();
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assert_eq!(result.as_int(), 1);
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}
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#[test]
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fn block_function_decl_hoisted_call_before_decl_is_not_callable() {
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// 阶段 1：声明点之前调用读到未初始化槽 undefined，报 not callable
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// （比修复前的编译错好；完整 hoisting 属后续阶段）。
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let err = eval("{ g(); function g(){return 1;} }").unwrap_err();
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assert!(err.contains("not callable") || err.contains("not an object"), "got: {err}");
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}
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#[test]
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fn block_function_decl_conflicts_with_let() {
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// 块内函数与块内 let 同名：早期错误（重复声明），顺序无关。
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let err = eval("{ let g; function g(){} }").unwrap_err();
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assert!(err.contains("already been declared"), "got: {err}");
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let err = eval("{ function g(){} let g; }").unwrap_err();
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assert!(err.contains("already been declared"), "got: {err}");
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}
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#[test]
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fn block_function_decl_capture_escape() {
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// 块内函数被外层变量引用（捕获路径 MAKE_CELL），块外可调用。
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let result = eval("var f; { function g(){return 1;} f = g; } f()").unwrap();
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assert_eq!(result.as_int(), 1);
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}
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#[test]
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fn block_function_decl_scope_isolated() {
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// 嵌套块内函数是块级绑定：块外不可见（typeof 未声明标识符返回 undefined）。
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let result = eval("{ { function g(){return 2;} } } typeof g === 'undefined'").unwrap();
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assert!(result.as_bool());
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}
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#[test]
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fn block_function_decl_duplicate_last_wins() {
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// 重复块内函数声明（sloppy）：最后声明生效（Annex B 语义）。
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let result = eval("{ function g(){} function g(){return 3;} g(); }").unwrap();
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assert_eq!(result.as_int(), 3);
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}
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#[test]
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fn block_function_decl_in_if_body() {
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// 单语句块体（if consequent 为块）：递归预声明生效。
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let result = eval("if (true) { function g(){return 8;} g(); }").unwrap();
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assert_eq!(result.as_int(), 8);
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}
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#[test]
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fn block_function_decl_nested_outer_var_capture() {
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// 嵌套块内函数引用外层变量，赋值逃逸后取值正确。
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let result = eval("var r; { { function g(){return 4;} r = g(); } } r").unwrap();
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assert_eq!(result.as_int(), 4);
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}
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