Auto merge of #16728 - Veykril:span-docs, r=Veykril

minor: Move span stuff around

Author: bors

Cargo.lock

@@ -6,14 +6,14 @@ use std::mem;
 use base_db::CrateId;
 use either::Either;
 use hir_expand::{
-    ast_id_map::AstIdMap,
     name::{name, AsName, Name},
     ExpandError, InFile,
 };
 use intern::Interned;
 use profile::Count;
 use rustc_hash::FxHashMap;
 use smallvec::SmallVec;
+use span::AstIdMap;
 use syntax::{
     ast::{
         self, ArrayExprKind, AstChildren, BlockExpr, HasArgList, HasAttrs, HasLoopBody, HasName,

crates/hir-def/src/body/lower.rs

@@ -47,18 +47,13 @@ use std::{
 use ast::{AstNode, StructKind};
 use base_db::CrateId;
 use either::Either;
-use hir_expand::{
-    ast_id_map::{AstIdNode, FileAstId},
-    attrs::RawAttrs,
-    name::Name,
-    ExpandTo, HirFileId, InFile,
-};
+use hir_expand::{attrs::RawAttrs, name::Name, ExpandTo, HirFileId, InFile};
 use intern::Interned;
 use la_arena::{Arena, Idx, IdxRange, RawIdx};
 use profile::Count;
 use rustc_hash::FxHashMap;
 use smallvec::SmallVec;
-use span::Span;
+use span::{AstIdNode, FileAstId, Span};
 use stdx::never;
 use syntax::{ast, match_ast, SyntaxKind};
 use triomphe::Arc;

crates/hir-def/src/item_tree.rs

@@ -2,10 +2,9 @@
 
 use std::collections::hash_map::Entry;
 
-use hir_expand::{
-    ast_id_map::AstIdMap, mod_path::path, name, name::AsName, span_map::SpanMapRef, HirFileId,
-};
+use hir_expand::{mod_path::path, name, name::AsName, span_map::SpanMapRef, HirFileId};
 use la_arena::Arena;
+use span::AstIdMap;
 use syntax::{
     ast::{self, HasModuleItem, HasName, HasTypeBounds, IsString},
     AstNode,

crates/hir-def/src/item_tree/lower.rs

@@ -76,7 +76,6 @@ use base_db::{
     CrateId, Edition,
 };
 use hir_expand::{
-    ast_id_map::{AstIdNode, FileAstId},
     builtin_attr_macro::BuiltinAttrExpander,
     builtin_derive_macro::BuiltinDeriveExpander,
     builtin_fn_macro::{BuiltinFnLikeExpander, EagerExpander},
@@ -91,7 +90,7 @@ use hir_expand::{
 use item_tree::ExternBlock;
 use la_arena::Idx;
 use nameres::DefMap;
-use span::{FileId, Span};
+use span::{AstIdNode, FileAstId, FileId, Span};
 use stdx::impl_from;
 use syntax::{ast, AstNode};
 

crates/hir-def/src/lib.rs

@@ -2,10 +2,10 @@
 use std::cell::OnceCell;
 
 use hir_expand::{
-    ast_id_map::{AstIdMap, AstIdNode},
     span_map::{SpanMap, SpanMapRef},
     AstId, HirFileId, InFile,
 };
+use span::{AstIdMap, AstIdNode};
 use syntax::ast;
 use triomphe::Arc;
 

crates/hir-def/src/lower.rs

@@ -61,13 +61,13 @@ use std::ops::Deref;
 
 use base_db::{CrateId, Edition, FileId};
 use hir_expand::{
-    ast_id_map::FileAstId, name::Name, proc_macro::ProcMacroKind, HirFileId, InFile, MacroCallId,
-    MacroDefId,
+    name::Name, proc_macro::ProcMacroKind, HirFileId, InFile, MacroCallId, MacroDefId,
 };
 use itertools::Itertools;
 use la_arena::Arena;
 use profile::Count;
 use rustc_hash::{FxHashMap, FxHashSet};
+use span::FileAstId;
 use stdx::format_to;
 use syntax::{ast, SmolStr};
 use triomphe::Arc;

crates/hir-def/src/nameres.rs

@@ -9,7 +9,6 @@ use base_db::{CrateId, Dependency, Edition, FileId};
 use cfg::{CfgExpr, CfgOptions};
 use either::Either;
 use hir_expand::{
-    ast_id_map::FileAstId,
     attrs::{Attr, AttrId},
     builtin_attr_macro::{find_builtin_attr, BuiltinAttrExpander},
     builtin_derive_macro::find_builtin_derive,
@@ -23,7 +22,7 @@ use itertools::{izip, Itertools};
 use la_arena::Idx;
 use limit::Limit;
 use rustc_hash::{FxHashMap, FxHashSet};
-use span::{ErasedFileAstId, Span, SyntaxContextId};
+use span::{ErasedFileAstId, FileAstId, Span, SyntaxContextId};
 use stdx::always;
 use syntax::{ast, SmolStr};
 use triomphe::Arc;

crates/hir-def/src/nameres/collector.rs

@@ -5,24 +5,20 @@ use either::Either;
 use limit::Limit;
 use mbe::{syntax_node_to_token_tree, ValueResult};
 use rustc_hash::FxHashSet;
-use span::SyntaxContextId;
+use span::{AstIdMap, SyntaxContextData, SyntaxContextId};
 use syntax::{
     ast::{self, HasAttrs},
     AstNode, Parse, SyntaxError, SyntaxNode, SyntaxToken, T,
 };
 use triomphe::Arc;
 
 use crate::{
-    ast_id_map::AstIdMap,
     attrs::collect_attrs,
     builtin_attr_macro::pseudo_derive_attr_expansion,
     builtin_fn_macro::EagerExpander,
     declarative::DeclarativeMacroExpander,
     fixup::{self, reverse_fixups, SyntaxFixupUndoInfo},
-    hygiene::{
-        span_with_call_site_ctxt, span_with_def_site_ctxt, span_with_mixed_site_ctxt,
-        SyntaxContextData,
-    },
+    hygiene::{span_with_call_site_ctxt, span_with_def_site_ctxt, span_with_mixed_site_ctxt},
     proc_macro::ProcMacros,
     span_map::{RealSpanMap, SpanMap, SpanMapRef},
     tt, AstId, BuiltinAttrExpander, BuiltinDeriveExpander, BuiltinFnLikeExpander,
@@ -61,7 +57,6 @@ pub trait ExpandDatabase: SourceDatabase {
     #[salsa::input]
     fn proc_macros(&self) -> Arc<ProcMacros>;
 
-    #[salsa::invoke(AstIdMap::new)]
     fn ast_id_map(&self, file_id: HirFileId) -> Arc<AstIdMap>;
 
     /// Main public API -- parses a hir file, not caring whether it's a real
@@ -256,6 +251,10 @@ pub fn expand_speculative(
     Some((node.syntax_node(), token))
 }
 
+fn ast_id_map(db: &dyn ExpandDatabase, file_id: span::HirFileId) -> triomphe::Arc<AstIdMap> {
+    triomphe::Arc::new(AstIdMap::from_source(&db.parse_or_expand(file_id)))
+}
+
 fn parse_or_expand(db: &dyn ExpandDatabase, file_id: HirFileId) -> SyntaxNode {
     match file_id.repr() {
         HirFileIdRepr::FileId(file_id) => db.parse(file_id).syntax_node(),

crates/hir-expand/src/db.rs

@@ -2,10 +2,16 @@
 use std::iter;
 
 use either::Either;
-use span::{FileId, FileRange, HirFileId, HirFileIdRepr, MacroFileId, SyntaxContextId};
-use syntax::{AstNode, SyntaxNode, SyntaxToken, TextRange, TextSize};
+use span::{
+    AstIdNode, ErasedFileAstId, FileAstId, FileId, FileRange, HirFileId, HirFileIdRepr,
+    MacroFileId, SyntaxContextId,
+};
+use syntax::{AstNode, AstPtr, SyntaxNode, SyntaxNodePtr, SyntaxToken, TextRange, TextSize};
 
-use crate::{db, map_node_range_up, span_for_offset, MacroFileIdExt};
+use crate::{
+    db::{self, ExpandDatabase},
+    map_node_range_up, span_for_offset, MacroFileIdExt,
+};
 
 /// `InFile<T>` stores a value of `T` inside a particular file/syntax tree.
 ///
@@ -23,6 +29,31 @@ pub type InFile<T> = InFileWrapper<HirFileId, T>;
 pub type InMacroFile<T> = InFileWrapper<MacroFileId, T>;
 pub type InRealFile<T> = InFileWrapper<FileId, T>;
 
+/// `AstId` points to an AST node in any file.
+///
+/// It is stable across reparses, and can be used as salsa key/value.
+pub type AstId<N> = crate::InFile<FileAstId<N>>;
+
+impl<N: AstIdNode> AstId<N> {
+    pub fn to_node(&self, db: &dyn ExpandDatabase) -> N {
+        self.to_ptr(db).to_node(&db.parse_or_expand(self.file_id))
+    }
+    pub fn to_in_file_node(&self, db: &dyn ExpandDatabase) -> crate::InFile<N> {
+        crate::InFile::new(self.file_id, self.to_ptr(db).to_node(&db.parse_or_expand(self.file_id)))
+    }
+    pub fn to_ptr(&self, db: &dyn ExpandDatabase) -> AstPtr<N> {
+        db.ast_id_map(self.file_id).get(self.value)
+    }
+}
+
+pub type ErasedAstId = crate::InFile<ErasedFileAstId>;
+
+impl ErasedAstId {
+    pub fn to_ptr(&self, db: &dyn ExpandDatabase) -> SyntaxNodePtr {
+        db.ast_id_map(self.file_id).get_erased(self.value)
+    }
+}
+
 impl<FileKind, T> InFileWrapper<FileKind, T> {
     pub fn new(file_id: FileKind, value: T) -> Self {
         Self { file_id, value }