diff --git a/crates/hir-def/src/item_tree/pretty.rs b/crates/hir-def/src/item_tree/pretty.rs
index d8a0cb5698..520034d213 100644
--- a/crates/hir-def/src/item_tree/pretty.rs
+++ b/crates/hir-def/src/item_tree/pretty.rs
@@ -2,6 +2,8 @@
 
 use std::fmt::{self, Write};
 
+use span::ErasedFileAstId;
+
 use crate::{
     generics::{TypeOrConstParamData, WherePredicate, WherePredicateTypeTarget},
     pretty::{print_path, print_type_bounds, print_type_ref},
@@ -118,7 +120,11 @@ impl Printer<'_> {
                 w!(self, "{{");
                 self.indented(|this| {
                     for field in fields.clone() {
-                        let Field { visibility, name, type_ref, ast_id: _ } = &this.tree[field];
+                        let Field { visibility, name, type_ref, ast_id } = &this.tree[field];
+                        this.print_ast_id(match ast_id {
+                            FieldAstId::Record(it) => it.erase(),
+                            FieldAstId::Tuple(it) => it.erase(),
+                        });
                         this.print_attrs_of(field, "\n");
                         this.print_visibility(*visibility);
                         w!(this, "{}: ", name.display(self.db.upcast()));
@@ -132,7 +138,11 @@ impl Printer<'_> {
                 w!(self, "(");
                 self.indented(|this| {
                     for field in fields.clone() {
-                        let Field { visibility, name, type_ref, ast_id: _ } = &this.tree[field];
+                        let Field { visibility, name, type_ref, ast_id } = &this.tree[field];
+                        this.print_ast_id(match ast_id {
+                            FieldAstId::Record(it) => it.erase(),
+                            FieldAstId::Tuple(it) => it.erase(),
+                        });
                         this.print_attrs_of(field, "\n");
                         this.print_visibility(*visibility);
                         w!(this, "{}: ", name.display(self.db.upcast()));
@@ -200,14 +210,16 @@ impl Printer<'_> {
 
         match item {
             ModItem::Use(it) => {
-                let Use { visibility, use_tree, ast_id: _ } = &self.tree[it];
+                let Use { visibility, use_tree, ast_id } = &self.tree[it];
+                self.print_ast_id(ast_id.erase());
                 self.print_visibility(*visibility);
                 w!(self, "use ");
                 self.print_use_tree(use_tree);
                 wln!(self, ";");
             }
             ModItem::ExternCrate(it) => {
-                let ExternCrate { name, alias, visibility, ast_id: _ } = &self.tree[it];
+                let ExternCrate { name, alias, visibility, ast_id } = &self.tree[it];
+                self.print_ast_id(ast_id.erase());
                 self.print_visibility(*visibility);
                 w!(self, "extern crate {}", name.display(self.db.upcast()));
                 if let Some(alias) = alias {
@@ -216,7 +228,8 @@ impl Printer<'_> {
                 wln!(self, ";");
             }
             ModItem::ExternBlock(it) => {
-                let ExternBlock { abi, ast_id: _, children } = &self.tree[it];
+                let ExternBlock { abi, ast_id, children } = &self.tree[it];
+                self.print_ast_id(ast_id.erase());
                 w!(self, "extern ");
                 if let Some(abi) = abi {
                     w!(self, "\"{}\" ", abi);
@@ -237,9 +250,10 @@ impl Printer<'_> {
                     abi,
                     params,
                     ret_type,
-                    ast_id: _,
+                    ast_id,
                     flags,
                 } = &self.tree[it];
+                self.print_ast_id(ast_id.erase());
                 self.print_visibility(*visibility);
                 if flags.contains(FnFlags::HAS_DEFAULT_KW) {
                     w!(self, "default ");
@@ -263,7 +277,12 @@ impl Printer<'_> {
                     self.indented(|this| {
                         for param in params.clone() {
                             this.print_attrs_of(param, "\n");
-                            match &this.tree[param].type_ref {
+                            let Param { type_ref, ast_id } = &this.tree[param];
+                            this.print_ast_id(match ast_id {
+                                ParamAstId::Param(it) => it.erase(),
+                                ParamAstId::SelfParam(it) => it.erase(),
+                            });
+                            match type_ref {
                                 Some(ty) => {
                                     if flags.contains(FnFlags::HAS_SELF_PARAM) {
                                         w!(this, "self: ");
@@ -288,7 +307,8 @@ impl Printer<'_> {
                 }
             }
             ModItem::Struct(it) => {
-                let Struct { visibility, name, fields, generic_params, ast_id: _ } = &self.tree[it];
+                let Struct { visibility, name, fields, generic_params, ast_id } = &self.tree[it];
+                self.print_ast_id(ast_id.erase());
                 self.print_visibility(*visibility);
                 w!(self, "struct {}", name.display(self.db.upcast()));
                 self.print_generic_params(generic_params);
@@ -300,7 +320,8 @@ impl Printer<'_> {
                 }
             }
             ModItem::Union(it) => {
-                let Union { name, visibility, fields, generic_params, ast_id: _ } = &self.tree[it];
+                let Union { name, visibility, fields, generic_params, ast_id } = &self.tree[it];
+                self.print_ast_id(ast_id.erase());
                 self.print_visibility(*visibility);
                 w!(self, "union {}", name.display(self.db.upcast()));
                 self.print_generic_params(generic_params);
@@ -312,14 +333,16 @@ impl Printer<'_> {
                 }
             }
             ModItem::Enum(it) => {
-                let Enum { name, visibility, variants, generic_params, ast_id: _ } = &self.tree[it];
+                let Enum { name, visibility, variants, generic_params, ast_id } = &self.tree[it];
+                self.print_ast_id(ast_id.erase());
                 self.print_visibility(*visibility);
                 w!(self, "enum {}", name.display(self.db.upcast()));
                 self.print_generic_params(generic_params);
                 self.print_where_clause_and_opening_brace(generic_params);
                 self.indented(|this| {
                     for variant in FileItemTreeId::range_iter(variants.clone()) {
-                        let Variant { name, fields, ast_id: _ } = &this.tree[variant];
+                        let Variant { name, fields, ast_id } = &this.tree[variant];
+                        this.print_ast_id(ast_id.erase());
                         this.print_attrs_of(variant, "\n");
                         w!(this, "{}", name.display(self.db.upcast()));
                         this.print_fields(fields);
@@ -329,7 +352,8 @@ impl Printer<'_> {
                 wln!(self, "}}");
             }
             ModItem::Const(it) => {
-                let Const { name, visibility, type_ref, ast_id: _ } = &self.tree[it];
+                let Const { name, visibility, type_ref, ast_id } = &self.tree[it];
+                self.print_ast_id(ast_id.erase());
                 self.print_visibility(*visibility);
                 w!(self, "const ");
                 match name {
@@ -341,7 +365,8 @@ impl Printer<'_> {
                 wln!(self, " = _;");
             }
             ModItem::Static(it) => {
-                let Static { name, visibility, mutable, type_ref, ast_id: _ } = &self.tree[it];
+                let Static { name, visibility, mutable, type_ref, ast_id } = &self.tree[it];
+                self.print_ast_id(ast_id.erase());
                 self.print_visibility(*visibility);
                 w!(self, "static ");
                 if *mutable {
@@ -353,15 +378,9 @@ impl Printer<'_> {
                 wln!(self);
             }
             ModItem::Trait(it) => {
-                let Trait {
-                    name,
-                    visibility,
-                    is_auto,
-                    is_unsafe,
-                    items,
-                    generic_params,
-                    ast_id: _,
-                } = &self.tree[it];
+                let Trait { name, visibility, is_auto, is_unsafe, items, generic_params, ast_id } =
+                    &self.tree[it];
+                self.print_ast_id(ast_id.erase());
                 self.print_visibility(*visibility);
                 if *is_unsafe {
                     w!(self, "unsafe ");
@@ -380,7 +399,8 @@ impl Printer<'_> {
                 wln!(self, "}}");
             }
             ModItem::TraitAlias(it) => {
-                let TraitAlias { name, visibility, generic_params, ast_id: _ } = &self.tree[it];
+                let TraitAlias { name, visibility, generic_params, ast_id } = &self.tree[it];
+                self.print_ast_id(ast_id.erase());
                 self.print_visibility(*visibility);
                 w!(self, "trait {}", name.display(self.db.upcast()));
                 self.print_generic_params(generic_params);
@@ -397,8 +417,9 @@ impl Printer<'_> {
                     is_unsafe,
                     items,
                     generic_params,
-                    ast_id: _,
+                    ast_id,
                 } = &self.tree[it];
+                self.print_ast_id(ast_id.erase());
                 if *is_unsafe {
                     w!(self, "unsafe");
                 }
@@ -422,8 +443,9 @@ impl Printer<'_> {
                 wln!(self, "}}");
             }
             ModItem::TypeAlias(it) => {
-                let TypeAlias { name, visibility, bounds, type_ref, generic_params, ast_id: _ } =
+                let TypeAlias { name, visibility, bounds, type_ref, generic_params, ast_id } =
                     &self.tree[it];
+                self.print_ast_id(ast_id.erase());
                 self.print_visibility(*visibility);
                 w!(self, "type {}", name.display(self.db.upcast()));
                 self.print_generic_params(generic_params);
@@ -440,7 +462,8 @@ impl Printer<'_> {
                 wln!(self);
             }
             ModItem::Mod(it) => {
-                let Mod { name, visibility, kind, ast_id: _ } = &self.tree[it];
+                let Mod { name, visibility, kind, ast_id } = &self.tree[it];
+                self.print_ast_id(ast_id.erase());
                 self.print_visibility(*visibility);
                 w!(self, "mod {}", name.display(self.db.upcast()));
                 match kind {
@@ -459,15 +482,24 @@ impl Printer<'_> {
                 }
             }
             ModItem::MacroCall(it) => {
-                let MacroCall { path, ast_id: _, expand_to: _, call_site: _ } = &self.tree[it];
+                let MacroCall { path, ast_id, expand_to, call_site } = &self.tree[it];
+                let _ = writeln!(
+                    self,
+                    "// AstId: {:?}, Span: {}, ExpandTo: {:?}",
+                    ast_id.erase().into_raw(),
+                    call_site,
+                    expand_to
+                );
                 wln!(self, "{}!(...);", path.display(self.db.upcast()));
             }
             ModItem::MacroRules(it) => {
-                let MacroRules { name, ast_id: _ } = &self.tree[it];
+                let MacroRules { name, ast_id } = &self.tree[it];
+                self.print_ast_id(ast_id.erase());
                 wln!(self, "macro_rules! {} {{ ... }}", name.display(self.db.upcast()));
             }
             ModItem::Macro2(it) => {
-                let Macro2 { name, visibility, ast_id: _ } = &self.tree[it];
+                let Macro2 { name, visibility, ast_id } = &self.tree[it];
+                self.print_ast_id(ast_id.erase());
                 self.print_visibility(*visibility);
                 wln!(self, "macro {} {{ ... }}", name.display(self.db.upcast()));
             }
@@ -583,6 +615,10 @@ impl Printer<'_> {
         });
         true
     }
+
+    fn print_ast_id(&mut self, ast_id: ErasedFileAstId) {
+        wln!(self, "// AstId: {:?}", ast_id.into_raw());
+    }
 }
 
 impl Write for Printer<'_> {
diff --git a/crates/hir-def/src/item_tree/tests.rs b/crates/hir-def/src/item_tree/tests.rs
index f97ae0d8e4..26f7b41c77 100644
--- a/crates/hir-def/src/item_tree/tests.rs
+++ b/crates/hir-def/src/item_tree/tests.rs
@@ -34,17 +34,23 @@ use a::{c, d::{e}};
             #![no_std]
             #![doc = " another file comment"]
 
+            // AstId: 1
             pub(self) extern crate self as renamed;
 
+            // AstId: 2
             pub(super) extern crate bli;
 
+            // AstId: 3
             pub use crate::path::{nested, items as renamed, Trait as _};
 
+            // AstId: 4
             pub(self) use globs::*;
 
             #[doc = " docs on import"]
+            // AstId: 5
             pub(self) use crate::{A, B};
 
+            // AstId: 6
             pub(self) use a::{c, d::{e}};
         "##]],
     );
@@ -68,14 +74,18 @@ extern "C" {
         "#,
         expect![[r##"
             #[on_extern_block]
+            // AstId: 1
             extern "C" {
                 #[on_extern_type]
+                // AstId: 2
                 pub(self) type ExType;
 
                 #[on_extern_static]
+                // AstId: 3
                 pub(self) static EX_STATIC: u8 = _;
 
                 #[on_extern_fn]
+                // AstId: 4
                 pub(self) fn ex_fn() -> ();
             }
         "##]],
@@ -112,38 +122,52 @@ enum E {
     }
 }
         "#,
-        expect![[r##"
+        expect![[r#"
+            // AstId: 1
             pub(self) struct Unit;
 
             #[derive(Debug)]
+            // AstId: 2
             pub(self) struct Struct {
+                // AstId: 6
                 #[doc = " fld docs"]
                 pub(self) fld: (),
             }
 
+            // AstId: 3
             pub(self) struct Tuple(
+                // AstId: 7
                 #[attr]
                 pub(self) 0: u8,
             );
 
+            // AstId: 4
             pub(self) union Ize {
+                // AstId: 8
                 pub(self) a: (),
+                // AstId: 9
                 pub(self) b: (),
             }
 
+            // AstId: 5
             pub(self) enum E {
+                // AstId: 10
                 #[doc = " comment on Unit"]
                 Unit,
+                // AstId: 11
                 #[doc = " comment on Tuple"]
                 Tuple(
+                    // AstId: 13
                     pub(self) 0: u8,
                 ),
+                // AstId: 12
                 Struct {
+                    // AstId: 14
                     #[doc = " comment on a: u8"]
                     pub(self) a: u8,
                 },
             }
-        "##]],
+        "#]],
     );
 }
 
@@ -166,26 +190,35 @@ trait Tr: SuperTrait + 'lifetime {
 }
         "#,
         expect![[r#"
+            // AstId: 1
             pub static mut ST: () = _;
 
+            // AstId: 2
             pub(self) const _: Anon = _;
 
             #[attr]
             #[inner_attr_in_fn]
+            // AstId: 3
             pub(self) fn f(
                 #[attr]
+                // AstId: 5
                 u8,
+                // AstId: 6
                 (),
             ) -> () { ... }
 
+            // AstId: 4
             pub(self) trait Tr<Self>
             where
                 Self: SuperTrait,
                 Self: 'lifetime
             {
+                // AstId: 8
                 pub(self) type Assoc: AssocBound = Default;
 
+                // AstId: 9
                 pub(self) fn method(
+                    // AstId: 10
                     self: &Self,
                 ) -> ();
             }
@@ -211,12 +244,16 @@ mod outline;
         expect![[r##"
             #[doc = " outer"]
             #[doc = " inner"]
+            // AstId: 1
             pub(self) mod inline {
+                // AstId: 3
                 pub(self) use super::*;
 
+                // AstId: 4
                 pub(self) fn fn_in_module() -> () { ... }
             }
 
+            // AstId: 2
             pub(self) mod outline;
         "##]],
     );
@@ -235,10 +272,13 @@ pub macro m2() {}
 m!();
         "#,
         expect![[r#"
+            // AstId: 1
             macro_rules! m { ... }
 
+            // AstId: 2
             pub macro m2 { ... }
 
+            // AstId: 3, Span: 0:3@0..5#0, ExpandTo: Items
             m!(...);
         "#]],
     );
@@ -258,12 +298,19 @@ struct S {
 }
         "#,
         expect![[r#"
+            // AstId: 1
             pub(self) struct S {
+                // AstId: 2
                 pub(self) a: self::Ty,
+                // AstId: 3
                 pub(self) b: super::SuperTy,
+                // AstId: 4
                 pub(self) c: super::super::SuperSuperTy,
+                // AstId: 5
                 pub(self) d: ::abs::Path,
+                // AstId: 6
                 pub(self) e: crate::Crate,
+                // AstId: 7
                 pub(self) f: plain::path::Ty,
             }
         "#]],
@@ -282,10 +329,15 @@ struct S {
 }
         "#,
         expect![[r#"
+            // AstId: 1
             pub(self) struct S {
+                // AstId: 2
                 pub(self) a: Mixed::<'a, T, Item = (), OtherItem = u8>,
+                // AstId: 3
                 pub(self) b: Qualified::<Self=Fully>::Syntax,
+                // AstId: 4
                 pub(self) c: <TypeAnchored>::Path::<'a>,
+                // AstId: 5
                 pub(self) d: dyn for<'a> Trait::<'a>,
             }
         "#]],
@@ -312,42 +364,53 @@ union Union<'a, T, const U: u8> {}
 trait Tr<'a, T: 'a>: Super where Self: for<'a> Tr<'a, T> {}
         "#,
         expect![[r#"
+            // AstId: 1
             pub(self) struct S<'a, 'b, T, const K: u8>
             where
                 T: Copy,
                 T: 'a,
                 T: 'b
             {
+                // AstId: 8
                 pub(self) field: &'a &'b T,
             }
 
+            // AstId: 2
             pub(self) struct Tuple<T, U>(
+                // AstId: 9
                 pub(self) 0: T,
+                // AstId: 10
                 pub(self) 1: U,
             )
             where
                 T: Copy,
                 U: ?Sized;
 
+            // AstId: 3
             impl<'a, 'b, T, const K: u8> S::<'a, 'b, T, K>
             where
                 T: Copy,
                 T: 'a,
                 T: 'b
             {
+                // AstId: 12
                 pub(self) fn f<G>(
+                    // AstId: 13
                     impl Copy,
                 ) -> impl Copy
                 where
                     G: 'a { ... }
             }
 
+            // AstId: 4
             pub(self) enum Enum<'a, T, const U: u8> {
             }
 
+            // AstId: 5
             pub(self) union Union<'a, T, const U: u8> {
             }
 
+            // AstId: 6
             pub(self) trait Tr<'a, Self, T>
             where
                 Self: Super,
@@ -366,6 +429,7 @@ fn generics_with_attributes() {
 struct S<#[cfg(never)] T>;
         "#,
         expect![[r#"
+            // AstId: 1
             pub(self) struct S<#[cfg(never)] T>;
         "#]],
     )
@@ -378,6 +442,7 @@ fn pub_self() {
 pub(self) struct S;
         "#,
         expect![[r#"
+            // AstId: 1
             pub(self) struct S;
         "#]],
     )