Auto merge of #117450 - oli-obk:rustdoc_verify, r=estebank

Accept less invalid Rust in rustdoc

pulled out of #117213 where this change was already approved

This only affects rustdoc, and has up to [20% perf regressions in rustdoc](#117213 (comment)). These are unavoidable, as we are simply doing more checks now, but it's part of the longer term plan of making rustdoc more resistant to ICEs by only accepting valid Rust code.

library/core/src/primitive_docs.rs

@@ -1077,26 +1077,6 @@ mod prim_tuple {}
 #[doc(hidden)]
 impl<T> (T,) {}
 
-// Fake impl that's only really used for docs.
-#[cfg(doc)]
-#[stable(feature = "rust1", since = "1.0.0")]
-#[doc(fake_variadic)]
-/// This trait is implemented on arbitrary-length tuples.
-impl<T: Clone> Clone for (T,) {
-    fn clone(&self) -> Self {
-        loop {}
-    }
-}
-
-// Fake impl that's only really used for docs.
-#[cfg(doc)]
-#[stable(feature = "rust1", since = "1.0.0")]
-#[doc(fake_variadic)]
-/// This trait is implemented on arbitrary-length tuples.
-impl<T: Copy> Copy for (T,) {
-    // empty
-}
-
 #[rustc_doc_primitive = "f32"]
 /// A 32-bit floating point type (specifically, the "binary32" type defined in IEEE 754-2008).
 ///

src/librustdoc/core.rs

@@ -319,10 +319,14 @@ pub(crate) fn run_global_ctxt(
         tcx.hir().for_each_module(|module| tcx.ensure().collect_mod_item_types(module))
     });
 
-    // NOTE: This is copy/pasted from typeck/lib.rs and should be kept in sync with those changes.
+    // NOTE: These are copy/pasted from typeck/lib.rs and should be kept in sync with those changes.
+    let _ = tcx.sess.time("wf_checking", || {
+        tcx.hir().try_par_for_each_module(|module| tcx.ensure().check_mod_type_wf(module))
+    });
     tcx.sess.time("item_types_checking", || {
         tcx.hir().for_each_module(|module| tcx.ensure().check_mod_item_types(module))
     });
+
     tcx.sess.abort_if_errors();
     tcx.sess.time("missing_docs", || rustc_lint::check_crate(tcx));
     tcx.sess.time("check_mod_attrs", || {

tests/rustdoc-gui/src/lib2/lib.rs

@@ -147,13 +147,13 @@ pub struct LongItemInfo2;
 #[doc(cfg(any(target_os = "android", target_os = "linux", target_os = "emscripten", target_os = "dragonfly", target_os = "freebsd", target_os = "netbsd", target_os = "openbsd")))]
 impl SimpleTrait for LongItemInfo2 {}
 
-pub struct WhereWhitespace<T>;
+pub struct WhereWhitespace<T>(T);
 
 impl<T> WhereWhitespace<T> {
     pub fn new<F>(f: F) -> Self
     where
         F: FnMut() -> i32,
-    {}
+    {todo!()}
 }
 
 impl<K, T> Whitespace<&K> for WhereWhitespace<T>
@@ -187,6 +187,11 @@ impl ItemInfoAlignmentTest {
 pub mod scroll_traits {
     use std::iter::*;
 
+    struct Intersperse<T>(T);
+    struct IntersperseWith<T, U>(T, U);
+    struct Flatten<T>(T);
+    struct Peekable<T>(T);
+
     /// Shamelessly (partially) copied from `std::iter::Iterator`.
     /// It allows us to check that the scroll is working as expected on "hidden" items.
     pub trait Iterator {

tests/rustdoc-json/enums/field_hidden.rs

@@ -1,7 +1,10 @@
 // Regression test for <https://github.com/rust-lang/rust/issues/100529>.
 
 #![no_core]
-#![feature(no_core)]
+#![feature(no_core, lang_items)]
+
+#[lang = "sized"]
+trait Sized {}
 
 // @has "$.index[*][?(@.name=='ParseError')]"
 // @has "$.index[*][?(@.name=='UnexpectedEndTag')]"

tests/rustdoc-json/enums/kind.rs

@@ -1,8 +1,11 @@
 // ignore-tidy-linelength
 
-#![feature(no_core)]
+#![feature(no_core, lang_items)]
 #![no_core]
 
+#[lang = "sized"]
+trait Sized {}
+
 pub enum Foo {
     // @set Unit = "$.index[*][?(@.name=='Unit')].id"
     // @is "$.index[*][?(@.name=='Unit')].inner.variant.kind" '"plain"'

tests/rustdoc-json/enums/tuple_fields_hidden.rs

@@ -1,6 +1,9 @@
-#![feature(no_core)]
+#![feature(no_core, lang_items)]
 #![no_core]
 
+#[lang = "sized"]
+trait Sized {}
+
 // @set 1.1.0 = "$.index[*][?(@.docs=='1.1.0')].id"
 // @set 2.1.0 = "$.index[*][?(@.docs=='2.1.0')].id"
 // @set 2.1.1 = "$.index[*][?(@.docs=='2.1.1')].id"

tests/rustdoc-json/generic-associated-types/gats.rs

@@ -1,11 +1,14 @@
 // ignore-tidy-linelength
 
 #![no_core]
-#![feature(lang_items, no_core)]
+#![feature(lang_items, no_core, arbitrary_self_types)]
 
 #[lang = "sized"]
 pub trait Sized {}
 
+#[lang = "receiver"]
+pub trait Receiver {}
+
 pub trait Display {}
 
 pub trait LendingIterator {

tests/rustdoc-json/impls/auto.rs

@@ -1,9 +1,12 @@
-#![feature(no_core, auto_traits, lang_items)]
+#![feature(no_core, auto_traits, lang_items, arbitrary_self_types)]
 #![no_core]
 
 #[lang = "sized"]
 trait Sized {}
 
+#[lang = "receiver"]
+pub trait Receiver {}
+
 pub auto trait Bar {}
 
 /// has span
@@ -12,8 +15,8 @@ impl Foo {
 }
 
 // Testing spans, so all tests below code
-// @is "$.index[*][?(@.docs=='has span')].span.begin" "[10, 0]"
-// @is "$.index[*][?(@.docs=='has span')].span.end" "[12, 1]"
+// @is "$.index[*][?(@.docs=='has span')].span.begin" "[13, 0]"
+// @is "$.index[*][?(@.docs=='has span')].span.end" "[15, 1]"
 // FIXME: this doesn't work due to https://github.com/freestrings/jsonpath/issues/91
 // is "$.index[*][?(@.inner.impl.synthetic==true)].span" null
 pub struct Foo;

tests/rustdoc-json/type/inherent_associated_type_bound.rs

@@ -16,5 +16,5 @@ pub struct Carrier<'a>(&'a ());
 pub fn user(_: for<'b> fn(Carrier<'b>::Focus<i32>)) {}
 
 impl<'a> Carrier<'a> {
-    pub type Focus<T> = &'a mut T;
+    pub type Focus<T> = &'a mut T where T: 'a;
 }

tests/rustdoc-ui/error-in-impl-trait/infinite-recursive-type-2.rs

@@ -1,7 +1,6 @@
-// check-pass
-
 pub fn f() -> impl Sized {
     pub enum E {
+        //~^ ERROR: recursive type
         V(E),
     }
 

tests/rustdoc-ui/error-in-impl-trait/infinite-recursive-type-2.stderr

@@ -0,0 +1,17 @@
+error[E0072]: recursive type `f::E` has infinite size
+  --> $DIR/infinite-recursive-type-2.rs:2:5
+   |
+LL |     pub enum E {
+   |     ^^^^^^^^^^
+LL |
+LL |         V(E),
+   |           - recursive without indirection
+   |
+help: insert some indirection (e.g., a `Box`, `Rc`, or `&`) to break the cycle
+   |
+LL |         V(Box<E>),
+   |           ++++ +
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0072`.

tests/rustdoc-ui/error-in-impl-trait/infinite-recursive-type.rs

@@ -1,7 +1,6 @@
-// check-pass
-
 fn f() -> impl Sized {
     enum E {
+        //~^ ERROR: recursive type
         V(E),
     }
 

tests/rustdoc-ui/error-in-impl-trait/infinite-recursive-type.stderr

@@ -0,0 +1,17 @@
+error[E0072]: recursive type `f::E` has infinite size
+  --> $DIR/infinite-recursive-type.rs:2:5
+   |
+LL |     enum E {
+   |     ^^^^^^
+LL |
+LL |         V(E),
+   |           - recursive without indirection
+   |
+help: insert some indirection (e.g., a `Box`, `Rc`, or `&`) to break the cycle
+   |
+LL |         V(Box<E>),
+   |           ++++ +
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0072`.

tests/rustdoc-ui/invalid_const_in_lifetime_position.rs

@@ -4,3 +4,8 @@ trait X {
 fn f<'a>(arg : Box<dyn X<Y<1> = &'a ()>>) {}
 //~^ ERROR associated type takes 1 lifetime argument but 0 lifetime arguments
 //~| ERROR associated type takes 0 generic arguments but 1 generic argument
+//~| ERROR associated type takes 1 lifetime argument but 0 lifetime arguments
+//~| ERROR associated type takes 0 generic arguments but 1 generic argument
+//~| ERROR associated type takes 1 lifetime argument but 0 lifetime arguments
+//~| ERROR associated type takes 0 generic arguments but 1 generic argument
+//~| ERROR trait `X` cannot be made into an object

tests/rustdoc-ui/invalid_const_in_lifetime_position.stderr

@@ -28,6 +28,86 @@ note: associated type defined here, with 0 generic parameters
 LL |     type Y<'a>;
    |          ^
 
-error: aborting due to 2 previous errors
+error[E0107]: associated type takes 1 lifetime argument but 0 lifetime arguments were supplied
+  --> $DIR/invalid_const_in_lifetime_position.rs:4:26
+   |
+LL | fn f<'a>(arg : Box<dyn X<Y<1> = &'a ()>>) {}
+   |                          ^ expected 1 lifetime argument
+   |
+note: associated type defined here, with 1 lifetime parameter: `'a`
+  --> $DIR/invalid_const_in_lifetime_position.rs:2:10
+   |
+LL |     type Y<'a>;
+   |          ^ --
+   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
+help: add missing lifetime argument
+   |
+LL | fn f<'a>(arg : Box<dyn X<Y<'_, 1> = &'a ()>>) {}
+   |                            +++
+
+error[E0107]: associated type takes 0 generic arguments but 1 generic argument was supplied
+  --> $DIR/invalid_const_in_lifetime_position.rs:4:26
+   |
+LL | fn f<'a>(arg : Box<dyn X<Y<1> = &'a ()>>) {}
+   |                          ^--- help: remove these generics
+   |                          |
+   |                          expected 0 generic arguments
+   |
+note: associated type defined here, with 0 generic parameters
+  --> $DIR/invalid_const_in_lifetime_position.rs:2:10
+   |
+LL |     type Y<'a>;
+   |          ^
+   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
+
+error[E0107]: associated type takes 1 lifetime argument but 0 lifetime arguments were supplied
+  --> $DIR/invalid_const_in_lifetime_position.rs:4:26
+   |
+LL | fn f<'a>(arg : Box<dyn X<Y<1> = &'a ()>>) {}
+   |                          ^ expected 1 lifetime argument
+   |
+note: associated type defined here, with 1 lifetime parameter: `'a`
+  --> $DIR/invalid_const_in_lifetime_position.rs:2:10
+   |
+LL |     type Y<'a>;
+   |          ^ --
+   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
+help: add missing lifetime argument
+   |
+LL | fn f<'a>(arg : Box<dyn X<Y<'_, 1> = &'a ()>>) {}
+   |                            +++
+
+error[E0107]: associated type takes 0 generic arguments but 1 generic argument was supplied
+  --> $DIR/invalid_const_in_lifetime_position.rs:4:26
+   |
+LL | fn f<'a>(arg : Box<dyn X<Y<1> = &'a ()>>) {}
+   |                          ^--- help: remove these generics
+   |                          |
+   |                          expected 0 generic arguments
+   |
+note: associated type defined here, with 0 generic parameters
+  --> $DIR/invalid_const_in_lifetime_position.rs:2:10
+   |
+LL |     type Y<'a>;
+   |          ^
+   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
+
+error[E0038]: the trait `X` cannot be made into an object
+  --> $DIR/invalid_const_in_lifetime_position.rs:4:20
+   |
+LL | fn f<'a>(arg : Box<dyn X<Y<1> = &'a ()>>) {}
+   |                    ^^^^^^^^^^^^^^^^^^^^ `X` cannot be made into an object
+   |
+note: for a trait to be "object safe" it needs to allow building a vtable to allow the call to be resolvable dynamically; for more information visit <https://doc.rust-lang.org/reference/items/traits.html#object-safety>
+  --> $DIR/invalid_const_in_lifetime_position.rs:2:10
+   |
+LL | trait X {
+   |       - this trait cannot be made into an object...
+LL |     type Y<'a>;
+   |          ^ ...because it contains the generic associated type `Y`
+   = help: consider moving `Y` to another trait
+
+error: aborting due to 7 previous errors
 
-For more information about this error, try `rustc --explain E0107`.
+Some errors have detailed explanations: E0038, E0107.
+For more information about an error, try `rustc --explain E0038`.

tests/rustdoc-ui/issues/issue-105742.rs

@@ -21,6 +21,8 @@ pub trait SVec: Index<
     //~| missing generics for associated type `SVec::Item`
     //~| missing generics for associated type `SVec::Item`
     //~| missing generics for associated type `SVec::Item`
+    //~| missing generics for associated type `SVec::Item`
+    //~| missing generics for associated type `SVec::Item`
     Output = <Index<<Self as SVec>::Item,
     //~^ expected 1 lifetime argument
     //~| expected 1 generic argument
@@ -30,6 +32,8 @@ pub trait SVec: Index<
     //~| missing generics for associated type `SVec::Item`
     //~| missing generics for associated type `SVec::Item`
     //~| missing generics for associated type `SVec::Item`
+    //~| missing generics for associated type `SVec::Item`
+    //~| missing generics for associated type `SVec::Item`
     Output = <Self as SVec>::Item> as SVec>::Item,
     //~^ expected 1 lifetime argument
     //~| expected 1 generic argument
@@ -47,6 +51,10 @@ pub trait SVec: Index<
     //~| missing generics for associated type `SVec::Item`
     //~| missing generics for associated type `SVec::Item`
     //~| missing generics for associated type `SVec::Item`
+    //~| missing generics for associated type `SVec::Item`
+    //~| missing generics for associated type `SVec::Item`
+    //~| missing generics for associated type `SVec::Item`
+    //~| missing generics for associated type `SVec::Item`
 > {
     type Item<'a, T>;