Merge pull request #18821 from ChayimFriedman2/coerce-pointee

feat: Support the new `CoercePointee` derive

Author: ChayimFriedman2

src/tools/rust-analyzer/crates/hir-def/src/macro_expansion_tests/builtin_derive_macro.rs

@@ -2,7 +2,7 @@
 
 use expect_test::expect;
 
-use crate::macro_expansion_tests::check;
+use crate::macro_expansion_tests::{check, check_errors};
 
 #[test]
 fn test_copy_expand_simple() {
@@ -16,7 +16,7 @@ struct Foo;
 #[derive(Copy)]
 struct Foo;
 
-impl < > $crate::marker::Copy for Foo< > where {}"#]],
+impl <> $crate::marker::Copy for Foo< > where {}"#]],
     );
 }
 
@@ -40,7 +40,7 @@ macro Copy {}
 #[derive(Copy)]
 struct Foo;
 
-impl < > $crate::marker::Copy for Foo< > where {}"#]],
+impl <> $crate::marker::Copy for Foo< > where {}"#]],
     );
 }
 
@@ -225,14 +225,14 @@ enum Bar {
     Bar,
 }
 
-impl < > $crate::default::Default for Foo< > where {
+impl <> $crate::default::Default for Foo< > where {
     fn default() -> Self {
         Foo {
             field1: $crate::default::Default::default(), field2: $crate::default::Default::default(),
         }
     }
 }
-impl < > $crate::default::Default for Bar< > where {
+impl <> $crate::default::Default for Bar< > where {
     fn default() -> Self {
         Bar::Bar
     }
@@ -260,7 +260,7 @@ enum Command {
     Jump,
 }
 
-impl < > $crate::cmp::PartialEq for Command< > where {
+impl <> $crate::cmp::PartialEq for Command< > where {
     fn eq(&self , other: &Self ) -> bool {
         match (self , other) {
             (Command::Move {
@@ -273,7 +273,7 @@ impl < > $crate::cmp::PartialEq for Command< > where {
         }
     }
 }
-impl < > $crate::cmp::Eq for Command< > where {}"#]],
+impl <> $crate::cmp::Eq for Command< > where {}"#]],
     );
 }
 
@@ -298,7 +298,7 @@ enum Command {
     Jump,
 }
 
-impl < > $crate::cmp::PartialEq for Command< > where {
+impl <> $crate::cmp::PartialEq for Command< > where {
     fn eq(&self , other: &Self ) -> bool {
         match (self , other) {
             (Command::Move {
@@ -311,7 +311,7 @@ impl < > $crate::cmp::PartialEq for Command< > where {
         }
     }
 }
-impl < > $crate::cmp::Eq for Command< > where {}"#]],
+impl <> $crate::cmp::Eq for Command< > where {}"#]],
     );
 }
 
@@ -335,7 +335,7 @@ enum Command {
     Jump,
 }
 
-impl < > $crate::cmp::PartialOrd for Command< > where {
+impl <> $crate::cmp::PartialOrd for Command< > where {
     fn partial_cmp(&self , other: &Self ) -> $crate::option::Option::Option<$crate::cmp::Ordering> {
         match $crate::intrinsics::discriminant_value(self ).partial_cmp(&$crate::intrinsics::discriminant_value(other)) {
             $crate::option::Option::Some($crate::cmp::Ordering::Equal)=> {
@@ -370,7 +370,7 @@ impl < > $crate::cmp::PartialOrd for Command< > where {
         }
     }
 }
-impl < > $crate::cmp::Ord for Command< > where {
+impl <> $crate::cmp::Ord for Command< > where {
     fn cmp(&self , other: &Self ) -> $crate::cmp::Ordering {
         match $crate::intrinsics::discriminant_value(self ).cmp(&$crate::intrinsics::discriminant_value(other)) {
             $crate::cmp::Ordering::Equal=> {
@@ -432,7 +432,7 @@ struct Foo {
     z: (i32, u64),
 }
 
-impl < > $crate::hash::Hash for Foo< > where {
+impl <> $crate::hash::Hash for Foo< > where {
     fn hash<H: $crate::hash::Hasher>(&self , ra_expand_state: &mut H) {
         match self {
             Foo {
@@ -470,7 +470,7 @@ enum Command {
     Jump,
 }
 
-impl < > $crate::hash::Hash for Command< > where {
+impl <> $crate::hash::Hash for Command< > where {
     fn hash<H: $crate::hash::Hasher>(&self , ra_expand_state: &mut H) {
         $crate::mem::discriminant(self ).hash(ra_expand_state);
         match self {
@@ -516,7 +516,7 @@ enum Command {
     Jump,
 }
 
-impl < > $crate::fmt::Debug for Command< > where {
+impl <> $crate::fmt::Debug for Command< > where {
     fn fmt(&self , f: &mut $crate::fmt::Formatter) -> $crate::fmt::Result {
         match self {
             Command::Move {
@@ -578,7 +578,7 @@ enum HideAndShowEnum {
     }
 }
 
-impl < > $crate::fmt::Debug for HideAndShow< > where {
+impl <> $crate::fmt::Debug for HideAndShow< > where {
     fn fmt(&self , f: &mut $crate::fmt::Formatter) -> $crate::fmt::Result {
         match self {
             HideAndShow {
@@ -588,7 +588,7 @@ impl < > $crate::fmt::Debug for HideAndShow< > where {
         }
     }
 }
-impl < > $crate::fmt::Debug for HideAndShowEnum< > where {
+impl <> $crate::fmt::Debug for HideAndShowEnum< > where {
     fn fmt(&self , f: &mut $crate::fmt::Formatter) -> $crate::fmt::Result {
         match self {
             HideAndShowEnum::AlwaysShow {
@@ -640,17 +640,109 @@ enum Bar {
     Bar,
 }
 
-impl < > $crate::default::Default for Foo< > where {
+impl <> $crate::default::Default for Foo< > where {
     fn default() -> Self {
         Foo {
             field1: $crate::default::Default::default(), field4: $crate::default::Default::default(),
         }
     }
 }
-impl < > $crate::default::Default for Bar< > where {
+impl <> $crate::default::Default for Bar< > where {
     fn default() -> Self {
         Bar::Bar
     }
 }"##]],
     );
 }
+
+#[test]
+fn coerce_pointee_expansion() {
+    check(
+        r#"
+//- minicore: coerce_pointee
+
+use core::marker::CoercePointee;
+
+pub trait Trait<T: ?Sized> {}
+
+#[derive(CoercePointee)]
+#[repr(transparent)]
+pub struct Foo<'a, T: ?Sized + Trait<U>, #[pointee] U: ?Sized, const N: u32>(T)
+where
+    U: Trait<U> + ToString;"#,
+        expect![[r#"
+
+use core::marker::CoercePointee;
+
+pub trait Trait<T: ?Sized> {}
+
+#[derive(CoercePointee)]
+#[repr(transparent)]
+pub struct Foo<'a, T: ?Sized + Trait<U>, #[pointee] U: ?Sized, const N: u32>(T)
+where
+    U: Trait<U> + ToString;
+impl <T, U, const N: u32, __S> $crate::ops::DispatchFromDyn<Foo<'a, T, __S, N>> for Foo<T, U, N, > where U: Trait<U> +ToString, T: Trait<__S>, __S: ?Sized, __S: Trait<__S> +ToString, U: ::core::marker::Unsize<__S>, T:?Sized+Trait<U>, U:?Sized, {}
+impl <T, U, const N: u32, __S> $crate::ops::CoerceUnsized<Foo<'a, T, __S, N>> for Foo<T, U, N, > where U: Trait<U> +ToString, T: Trait<__S>, __S: ?Sized, __S: Trait<__S> +ToString, U: ::core::marker::Unsize<__S>, T:?Sized+Trait<U>, U:?Sized, {}"#]],
+    );
+}
+
+#[test]
+fn coerce_pointee_errors() {
+    check_errors(
+        r#"
+//- minicore: coerce_pointee
+
+use core::marker::CoercePointee;
+
+#[derive(CoercePointee)]
+enum Enum {}
+
+#[derive(CoercePointee)]
+struct Struct1;
+
+#[derive(CoercePointee)]
+struct Struct2();
+
+#[derive(CoercePointee)]
+struct Struct3 {}
+
+#[derive(CoercePointee)]
+struct Struct4<T: ?Sized>(T);
+
+#[derive(CoercePointee)]
+#[repr(transparent)]
+struct Struct5(i32);
+
+#[derive(CoercePointee)]
+#[repr(transparent)]
+struct Struct6<#[pointee] T: ?Sized, #[pointee] U: ?Sized>(T, U);
+
+#[derive(CoercePointee)]
+#[repr(transparent)]
+struct Struct7<T: ?Sized, U: ?Sized>(T, U);
+
+#[derive(CoercePointee)]
+#[repr(transparent)]
+struct Struct8<#[pointee] T, U: ?Sized>(T);
+
+#[derive(CoercePointee)]
+#[repr(transparent)]
+struct Struct9<T>(T);
+
+#[derive(CoercePointee)]
+#[repr(transparent)]
+struct Struct9<#[pointee] T, U>(T) where T: ?Sized;
+"#,
+        expect![[r#"
+            35..72: `CoercePointee` can only be derived on `struct`s
+            74..114: `CoercePointee` can only be derived on `struct`s with at least one field
+            116..158: `CoercePointee` can only be derived on `struct`s with at least one field
+            160..202: `CoercePointee` can only be derived on `struct`s with at least one field
+            204..258: `CoercePointee` can only be derived on `struct`s with `#[repr(transparent)]`
+            260..326: `CoercePointee` can only be derived on `struct`s that are generic over at least one type
+            328..439: only one type parameter can be marked as `#[pointee]` when deriving `CoercePointee` traits
+            441..530: exactly one generic type parameter must be marked as `#[pointee]` to derive `CoercePointee` traits
+            532..621: `derive(CoercePointee)` requires `T` to be marked `?Sized`
+            623..690: `derive(CoercePointee)` requires `T` to be marked `?Sized`"#]],
+    );
+}

src/tools/rust-analyzer/crates/hir-def/src/macro_expansion_tests/mod.rs

@@ -16,14 +16,16 @@ mod proc_macros;
 
 use std::{iter, ops::Range, sync};
 
+use base_db::SourceDatabase;
 use expect_test::Expect;
 use hir_expand::{
     db::ExpandDatabase,
     proc_macro::{ProcMacro, ProcMacroExpander, ProcMacroExpansionError, ProcMacroKind},
     span_map::SpanMapRef,
-    InFile, MacroFileId, MacroFileIdExt,
+    InFile, MacroCallKind, MacroFileId, MacroFileIdExt,
 };
 use intern::Symbol;
+use itertools::Itertools;
 use span::{Edition, Span};
 use stdx::{format_to, format_to_acc};
 use syntax::{
@@ -44,6 +46,36 @@ use crate::{
     AdtId, AsMacroCall, Lookup, ModuleDefId,
 };
 
+#[track_caller]
+fn check_errors(ra_fixture: &str, expect: Expect) {
+    let db = TestDB::with_files(ra_fixture);
+    let krate = db.fetch_test_crate();
+    let def_map = db.crate_def_map(krate);
+    let errors = def_map
+        .modules()
+        .flat_map(|module| module.1.scope.all_macro_calls())
+        .filter_map(|macro_call| {
+            let errors = db.parse_macro_expansion_error(macro_call)?;
+            let errors = errors.err.as_ref()?.render_to_string(&db);
+            let macro_loc = db.lookup_intern_macro_call(macro_call);
+            let ast_id = match macro_loc.kind {
+                MacroCallKind::FnLike { ast_id, .. } => ast_id.map(|it| it.erase()),
+                MacroCallKind::Derive { ast_id, .. } => ast_id.map(|it| it.erase()),
+                MacroCallKind::Attr { ast_id, .. } => ast_id.map(|it| it.erase()),
+            };
+            let ast = db
+                .parse(ast_id.file_id.file_id().expect("macros inside macros are not supported"))
+                .syntax_node();
+            let ast_id_map = db.ast_id_map(ast_id.file_id);
+            let node = ast_id_map.get_erased(ast_id.value).to_node(&ast);
+            Some((node.text_range(), errors))
+        })
+        .sorted_unstable_by_key(|(range, _)| range.start())
+        .format_with("\n", |(range, err), format| format(&format_args!("{range:?}: {err}")))
+        .to_string();
+    expect.assert_eq(&errors);
+}
+
 #[track_caller]
 fn check(ra_fixture: &str, mut expect: Expect) {
     let extra_proc_macros = vec![(
@@ -245,7 +277,9 @@ fn pretty_print_macro_expansion(
     let mut res = String::new();
     let mut prev_kind = EOF;
     let mut indent_level = 0;
-    for token in iter::successors(expn.first_token(), |t| t.next_token()) {
+    for token in iter::successors(expn.first_token(), |t| t.next_token())
+        .take_while(|token| token.text_range().start() < expn.text_range().end())
+    {
         let curr_kind = token.kind();
         let space = match (prev_kind, curr_kind) {
             _ if prev_kind.is_trivia() || curr_kind.is_trivia() => "",