Auto merge of rust-lang#98152 - JohnTitor:rollup-osr17j6, r=JohnTitor

Rollup of 7 pull requests

Successful merges:

 - rust-lang#97202 (os str capacity documentation)
 - rust-lang#97964 (Fix suggestions for `&a: T` parameters)
 - rust-lang#98053 (Fix generic impl rustdoc json output)
 - rust-lang#98059 (Inline `const_eval_select`)
 - rust-lang#98092 (Fix sidebar items expand collapse)
 - rust-lang#98119 (Refactor path segment parameter error)
 - rust-lang#98135 (Add regression test for rust-lang#93775)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup

Author: bors

compiler/rustc_ast_lowering/src/path.rs

@@ -196,25 +196,32 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
                     ParenthesizedGenericArgs::Err => {
                         let mut err = struct_span_err!(self.sess, data.span, E0214, "{}", msg);
                         err.span_label(data.span, "only `Fn` traits may use parentheses");
-                        if let Ok(snippet) = self.sess.source_map().span_to_snippet(data.span) {
-                            // Do not suggest going from `Trait()` to `Trait<>`
-                            if !data.inputs.is_empty() {
-                                // Suggest replacing `(` and `)` with `<` and `>`
-                                // The snippet may be missing the closing `)`, skip that case
-                                if snippet.ends_with(')') {
-                                    if let Some(split) = snippet.find('(') {
-                                        let trait_name = &snippet[0..split];
-                                        let args = &snippet[split + 1..snippet.len() - 1];
-                                        err.span_suggestion(
-                                            data.span,
-                                            "use angle brackets instead",
-                                            format!("{}<{}>", trait_name, args),
-                                            Applicability::MaybeIncorrect,
-                                        );
-                                    }
-                                }
-                            }
-                        };
+                        // Suggest replacing parentheses with angle brackets `Trait(params...)` to `Trait<params...>`
+                        if !data.inputs.is_empty() {
+                            // Start of the span to the 1st character of 1st argument
+                            let open_param = data.inputs_span.shrink_to_lo().to(data
+                                .inputs
+                                .first()
+                                .unwrap()
+                                .span
+                                .shrink_to_lo());
+                            // Last character position of last argument to the end of the span
+                            let close_param = data
+                                .inputs
+                                .last()
+                                .unwrap()
+                                .span
+                                .shrink_to_hi()
+                                .to(data.inputs_span.shrink_to_hi());
+                            err.multipart_suggestion(
+                                &format!("use angle brackets instead",),
+                                vec![
+                                    (open_param, String::from("<")),
+                                    (close_param, String::from(">")),
+                                ],
+                                Applicability::MaybeIncorrect,
+                            );
+                        }
                         err.emit();
                         (
                             self.lower_angle_bracketed_parameter_data(

compiler/rustc_typeck/src/check/pat.rs

@@ -649,39 +649,41 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         }
     }
 
-    fn borrow_pat_suggestion(
-        &self,
-        err: &mut Diagnostic,
-        pat: &Pat<'_>,
-        inner: &Pat<'_>,
-        expected: Ty<'tcx>,
-    ) {
+    // Precondition: pat is a Ref(_) pattern
+    fn borrow_pat_suggestion(&self, err: &mut Diagnostic, pat: &Pat<'_>) {
         let tcx = self.tcx;
-        if let PatKind::Binding(..) = inner.kind {
+        if let PatKind::Ref(inner, mutbl) = pat.kind
+        && let PatKind::Binding(_, _, binding, ..) = inner.kind {
             let binding_parent_id = tcx.hir().get_parent_node(pat.hir_id);
             let binding_parent = tcx.hir().get(binding_parent_id);
-            debug!("inner {:?} pat {:?} parent {:?}", inner, pat, binding_parent);
+            debug!(?inner, ?pat, ?binding_parent);
+
+            let mutability = match mutbl {
+                ast::Mutability::Mut => "mut",
+                ast::Mutability::Not => "",
+            };
+
             match binding_parent {
-                hir::Node::Param(hir::Param { span, .. })
-                    if let Ok(snippet) = tcx.sess.source_map().span_to_snippet(inner.span) =>
-                {
-                    err.span_suggestion(
-                        *span,
-                        &format!("did you mean `{snippet}`"),
-                        format!(" &{expected}"),
-                        Applicability::MachineApplicable,
+                // Check that there is explicit type (ie this is not a closure param with inferred type)
+                // so we don't suggest moving something to the type that does not exist
+                hir::Node::Param(hir::Param { ty_span, .. }) if binding.span != *ty_span => {
+                    err.multipart_suggestion_verbose(
+                        format!("to take parameter `{binding}` by reference, move `&{mutability}` to the type"),
+                        vec![
+                            (pat.span.until(inner.span), "".to_owned()),
+                            (ty_span.shrink_to_lo(), format!("&{}", mutbl.prefix_str())),
+                        ],
+                        Applicability::MachineApplicable
                     );
                 }
-                hir::Node::Arm(_) | hir::Node::Pat(_) => {
+                hir::Node::Param(_) | hir::Node::Arm(_) | hir::Node::Pat(_) => {
                     // rely on match ergonomics or it might be nested `&&pat`
-                    if let Ok(snippet) = tcx.sess.source_map().span_to_snippet(inner.span) {
-                        err.span_suggestion(
-                            pat.span,
-                            "you can probably remove the explicit borrow",
-                            snippet,
-                            Applicability::MaybeIncorrect,
-                        );
-                    }
+                    err.span_suggestion_verbose(
+                        pat.span.until(inner.span),
+                        format!("consider removing `&{mutability}` from the pattern"),
+                        "",
+                        Applicability::MaybeIncorrect,
+                    );
                 }
                 _ => {} // don't provide suggestions in other cases #55175
             }
@@ -1836,6 +1838,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         box_ty
     }
 
+    // Precondition: Pat is Ref(inner)
     fn check_pat_ref(
         &self,
         pat: &'tcx Pat<'tcx>,
@@ -1853,7 +1856,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
 
             // Take region, inner-type from expected type if we can,
             // to avoid creating needless variables. This also helps with
-            // the bad  interactions of the given hack detailed in (note_1).
+            // the bad interactions of the given hack detailed in (note_1).
             debug!("check_pat_ref: expected={:?}", expected);
             match *expected.kind() {
                 ty::Ref(_, r_ty, r_mutbl) if r_mutbl == mutbl => (expected, r_ty),
@@ -1869,7 +1872,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                     // Look for a case like `fn foo(&foo: u32)` and suggest
                     // `fn foo(foo: &u32)`
                     if let Some(mut err) = err {
-                        self.borrow_pat_suggestion(&mut err, pat, inner, expected);
+                        self.borrow_pat_suggestion(&mut err, pat);
                         err.emit();
                     }
                     (rptr_ty, inner_ty)

library/core/src/intrinsics.rs

@@ -2363,6 +2363,7 @@ pub const unsafe fn write_bytes<T>(dst: *mut T, val: u8, count: usize) {
 #[rustc_const_unstable(feature = "const_eval_select", issue = "none")]
 #[lang = "const_eval_select"]
 #[rustc_do_not_const_check]
+#[inline]
 pub const unsafe fn const_eval_select<ARG, F, G, RET>(
     arg: ARG,
     _called_in_const: F,

library/std/src/ffi/os_str.rs

@@ -45,6 +45,22 @@ use crate::sys_common::{AsInner, FromInner, IntoInner};
 /// values, encoded in a less-strict variant of UTF-8. This is useful to
 /// understand when handling capacity and length values.
 ///
+/// # Capacity of `OsString`
+///
+/// Capacity uses units of UTF-8 bytes for OS strings which were created from valid unicode, and
+/// uses units of bytes in an unspecified encoding for other contents. On a given target, all
+/// `OsString` and `OsStr` values use the same units for capacity, so the following will work:
+/// ```
+/// use std::ffi::{OsStr, OsString};
+///
+/// fn concat_os_strings(a: &OsStr, b: &OsStr) -> OsString {
+///     let mut ret = OsString::with_capacity(a.len() + b.len()); // This will allocate
+///     ret.push(a); // This will not allocate further
+///     ret.push(b); // This will not allocate further
+///     ret
+/// }
+/// ```
+///
 /// # Creating an `OsString`
 ///
 /// **From a Rust string**: `OsString` implements
@@ -186,7 +202,7 @@ impl OsString {
     /// OS strings without reallocating. If `capacity` is 0, the string will not
     /// allocate.
     ///
-    /// See main `OsString` documentation information about encoding.
+    /// See the main `OsString` documentation information about encoding and capacity units.
     ///
     /// # Examples
     ///
@@ -229,7 +245,7 @@ impl OsString {
 
     /// Returns the capacity this `OsString` can hold without reallocating.
     ///
-    /// See `OsString` introduction for information about encoding.
+    /// See the main `OsString` documentation information about encoding and capacity units.
     ///
     /// # Examples
     ///
@@ -251,6 +267,8 @@ impl OsString {
     ///
     /// The collection may reserve more space to avoid frequent reallocations.
     ///
+    /// See the main `OsString` documentation information about encoding and capacity units.
+    ///
     /// # Examples
     ///
     /// ```
@@ -272,6 +290,8 @@ impl OsString {
     /// greater than or equal to `self.len() + additional`. Does nothing if
     /// capacity is already sufficient.
     ///
+    /// See the main `OsString` documentation information about encoding and capacity units.
+    ///
     /// # Errors
     ///
     /// If the capacity overflows, or the allocator reports a failure, then an error
@@ -313,6 +333,8 @@ impl OsString {
     ///
     /// [`reserve`]: OsString::reserve
     ///
+    /// See the main `OsString` documentation information about encoding and capacity units.
+    ///
     /// # Examples
     ///
     /// ```
@@ -340,6 +362,8 @@ impl OsString {
     ///
     /// [`try_reserve`]: OsString::try_reserve
     ///
+    /// See the main `OsString` documentation information about encoding and capacity units.
+    ///
     /// # Errors
     ///
     /// If the capacity overflows, or the allocator reports a failure, then an error
@@ -373,6 +397,8 @@ impl OsString {
 
     /// Shrinks the capacity of the `OsString` to match its length.
     ///
+    /// See the main `OsString` documentation information about encoding and capacity units.
+    ///
     /// # Examples
     ///
     /// ```
@@ -399,6 +425,8 @@ impl OsString {
     ///
     /// If the current capacity is less than the lower limit, this is a no-op.
     ///
+    /// See the main `OsString` documentation information about encoding and capacity units.
+    ///
     /// # Examples
     ///
     /// ```
@@ -773,6 +801,8 @@ impl OsStr {
     /// This number is simply useful for passing to other methods, like
     /// [`OsString::with_capacity`] to avoid reallocations.
     ///
+    /// See the main `OsString` documentation information about encoding and capacity units.
+    ///
     /// # Examples
     ///
     /// ```

src/librustdoc/html/static/js/source-script.js

@@ -32,10 +32,10 @@ function createDirEntry(elem, parent, fullPath, currentFile, hasFoundFile) {
     fullPath += elem["name"] + "/";
 
     name.onclick = () => {
-        if (hasClass(this, "expand")) {
-            removeClass(this, "expand");
+        if (hasClass(name, "expand")) {
+            removeClass(name, "expand");
         } else {
-            addClass(this, "expand");
+            addClass(name, "expand");
         }
     };
     name.innerText = elem["name"];

src/librustdoc/json/mod.rs

@@ -181,15 +181,44 @@ impl<'tcx> FormatRenderer<'tcx> for JsonRenderer<'tcx> {
         let name = item.name;
         let item_id = item.item_id;
         if let Some(mut new_item) = self.convert_item(item) {
-            if let types::ItemEnum::Trait(ref mut t) = new_item.inner {
-                t.implementations = self.get_trait_implementors(item_id.expect_def_id())
-            } else if let types::ItemEnum::Struct(ref mut s) = new_item.inner {
-                s.impls = self.get_impls(item_id.expect_def_id())
-            } else if let types::ItemEnum::Enum(ref mut e) = new_item.inner {
-                e.impls = self.get_impls(item_id.expect_def_id())
-            } else if let types::ItemEnum::Union(ref mut u) = new_item.inner {
-                u.impls = self.get_impls(item_id.expect_def_id())
-            }
+            let can_be_ignored = match new_item.inner {
+                types::ItemEnum::Trait(ref mut t) => {
+                    t.implementations = self.get_trait_implementors(item_id.expect_def_id());
+                    false
+                }
+                types::ItemEnum::Struct(ref mut s) => {
+                    s.impls = self.get_impls(item_id.expect_def_id());
+                    false
+                }
+                types::ItemEnum::Enum(ref mut e) => {
+                    e.impls = self.get_impls(item_id.expect_def_id());
+                    false
+                }
+                types::ItemEnum::Union(ref mut u) => {
+                    u.impls = self.get_impls(item_id.expect_def_id());
+                    false
+                }
+
+                types::ItemEnum::Method(_)
+                | types::ItemEnum::AssocConst { .. }
+                | types::ItemEnum::AssocType { .. } => true,
+                types::ItemEnum::Module(_)
+                | types::ItemEnum::ExternCrate { .. }
+                | types::ItemEnum::Import(_)
+                | types::ItemEnum::StructField(_)
+                | types::ItemEnum::Variant(_)
+                | types::ItemEnum::Function(_)
+                | types::ItemEnum::TraitAlias(_)
+                | types::ItemEnum::Impl(_)
+                | types::ItemEnum::Typedef(_)
+                | types::ItemEnum::OpaqueTy(_)
+                | types::ItemEnum::Constant(_)
+                | types::ItemEnum::Static(_)
+                | types::ItemEnum::ForeignType
+                | types::ItemEnum::Macro(_)
+                | types::ItemEnum::ProcMacro(_)
+                | types::ItemEnum::PrimitiveType(_) => false,
+            };
             let removed = self
                 .index
                 .borrow_mut()
@@ -199,7 +228,11 @@ impl<'tcx> FormatRenderer<'tcx> for JsonRenderer<'tcx> {
             // to make sure the items are unique. The main place this happens is when an item, is
             // reexported in more than one place. See `rustdoc-json/reexport/in_root_and_mod`
             if let Some(old_item) = removed {
-                assert_eq!(old_item, new_item);
+                // In case of generic implementations (like `impl<T> Trait for T {}`), all the
+                // inner items will be duplicated so we can ignore if they are slightly different.
+                if !can_be_ignored {
+                    assert_eq!(old_item, new_item);
+                }
             }
         }
 

src/test/rustdoc-gui/source-code-page.goml

@@ -1,4 +1,4 @@
-// Checks that the interactions with the source code pages are workined as expected.
+// Checks that the interactions with the source code pages are working as expected.
 goto: file://|DOC_PATH|/src/test_docs/lib.rs.html
 // Check that we can click on the line number.
 click: ".line-numbers > span:nth-child(4)" // This is the span for line 4.
@@ -27,3 +27,26 @@ assert-position: ("//*[@id='1']", {"x": 104, "y": 103})
 // We click on the left of the "1" span but still in the "line-number" `<pre>`.
 click: (103, 103)
 assert-document-property: ({"URL": "/lib.rs.html"}, ENDS_WITH)
+
+// Checking the source code sidebar.
+
+// First we "open" it.
+click: "#sidebar-toggle"
+assert: ".sidebar.expanded"
+
+// We check that the first entry of the sidebar is collapsed (which, for whatever reason,
+// is number 2 and not 1...).
+assert-attribute: ("#source-sidebar .name:nth-child(2)", {"class": "name"})
+assert-text: ("#source-sidebar .name:nth-child(2)", "implementors")
+// We also check its children are hidden too.
+assert-css: ("#source-sidebar .name:nth-child(2) + .children", {"display": "none"})
+// We now click on it.
+click: "#source-sidebar .name:nth-child(2)"
+assert-attribute: ("#source-sidebar .name:nth-child(2)", {"class": "name expand"})
+// Checking that its children are displayed as well.
+assert-css: ("#source-sidebar .name:nth-child(2) + .children", {"display": "block"})
+
+// And now we collapse it again.
+click: "#source-sidebar .name:nth-child(2)"
+assert-attribute: ("#source-sidebar .name:nth-child(2)", {"class": "name"})
+assert-css: ("#source-sidebar .name:nth-child(2) + .children", {"display": "none"})

src/test/rustdoc-json/generic_impl.rs

@@ -0,0 +1,24 @@
+// Regression test for <https://github.com/rust-lang/rust/issues/97986>.
+
+// @has generic_impl.json
+// @has - "$.index[*][?(@.name=='f')]"
+// @has - "$.index[*][?(@.name=='AssocTy')]"
+// @has - "$.index[*][?(@.name=='AssocConst')]"
+
+pub mod m {
+    pub struct S;
+}
+
+pub trait F {
+    type AssocTy;
+    const AssocConst: usize;
+    fn f() -> m::S;
+}
+
+impl<T> F for T {
+    type AssocTy = u32;
+    const AssocConst: usize = 0;
+    fn f() -> m::S {
+        m::S
+    }
+}