feat: allow to get current StmtInfo in visiting ast (#370)

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### Description

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### Test Plan

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---

crates/rolldown/src/bundler/module/normal_module.rs

@@ -76,7 +76,7 @@ impl NormalModule {
     );
 
     let render_kind = RenderKind::from_wrap_kind(&self_linking_info.wrap_kind);
-    let mut renderer = AstRenderer::new(base, render_kind);
+    let mut renderer = AstRenderer::new(base, &self.stmt_infos, render_kind);
     renderer.render();
 
     source.prepend(format!("// {}\n", self.pretty_path));

crates/rolldown/src/bundler/renderer/impl_visit.rs

@@ -16,7 +16,11 @@ impl<'ast, 'r> Visit<'ast> for AstRenderer<'r> {
     for directive in &program.directives {
       self.visit_directive(directive);
     }
-    self.visit_statements(&program.body);
+    for (stmt_idx, stmt) in program.body.iter().enumerate() {
+      self.current_stmt_info.next();
+      debug_assert!(self.current_stmt_info.get().stmt_idx == Some(stmt_idx));
+      self.visit_statement(stmt);
+    }
   }
 
   fn visit_binding_identifier(&mut self, ident: &oxc::ast::ast::BindingIdentifier) {

crates/rolldown/src/bundler/renderer/mod.rs

@@ -9,7 +9,7 @@ use oxc::{
   ast::Visit,
   span::{Atom, GetSpan, Span},
 };
-use rolldown_common::{ExportsKind, SymbolRef, WrapKind};
+use rolldown_common::{ExportsKind, StmtInfo, StmtInfoId, StmtInfos, SymbolRef, WrapKind};
 use rolldown_oxc::BindingIdentifierExt;
 use rolldown_utils::MagicStringExt;
 use rustc_hash::FxHashMap;
@@ -88,21 +88,47 @@ impl RenderKind {
   }
 }
 
+#[derive(Debug)]
+struct CurrentStmtInfo<'a> {
+  stmts_infos: &'a StmtInfos,
+  current_idx: StmtInfoId,
+}
+
+impl<'a> CurrentStmtInfo<'a> {
+  pub fn new(stmts_infos: &'a StmtInfos) -> Self {
+    Self { stmts_infos, current_idx: StmtInfoId::from_raw(0) }
+  }
+
+  pub fn get(&self) -> &StmtInfo {
+    // 0 represents the facade namespace declaration statement, so it should not be used here.
+    debug_assert!(self.current_idx.raw() != 0);
+    let stmt_info = &self.stmts_infos[self.current_idx];
+    debug_assert!(stmt_info.stmt_idx.is_some(), "Facade statement should not be used here");
+    stmt_info
+  }
+
+  pub fn next(&mut self) {
+    self.current_idx = StmtInfoId::from_raw(self.current_idx.raw() + 1);
+  }
+}
+
 #[derive(Debug)]
 pub struct AstRenderer<'r> {
   ctx: AstRenderContext<'r>,
   wrapped_esm_ctx: WrappedEsmCtx,
   kind: RenderKind,
   indentor: String,
+  current_stmt_info: CurrentStmtInfo<'r>,
 }
 
 impl<'r> AstRenderer<'r> {
-  pub fn new(ctx: AstRenderContext<'r>, kind: RenderKind) -> Self {
+  pub fn new(ctx: AstRenderContext<'r>, stmts_infos: &'r StmtInfos, kind: RenderKind) -> Self {
     Self {
       kind,
       indentor: ctx.source.guessed_indentor().to_string(),
       ctx,
       wrapped_esm_ctx: WrappedEsmCtx::default(),
+      current_stmt_info: CurrentStmtInfo::new(stmts_infos),
     }
   }
 }