Rollup of 7 pull requests

compiler/rustc_parse/src/parser/item.rs

@@ -1283,12 +1283,10 @@ impl<'a> Parser<'a> {
     /// Parses an enum declaration.
     fn parse_item_enum(&mut self) -> PResult<'a, ItemInfo> {
         if self.token.is_keyword(kw::Struct) {
-            let mut err = self.struct_span_err(
-                self.prev_token.span.to(self.token.span),
-                "`enum` and `struct` are mutually exclusive",
-            );
+            let span = self.prev_token.span.to(self.token.span);
+            let mut err = self.struct_span_err(span, "`enum` and `struct` are mutually exclusive");
             err.span_suggestion(
-                self.prev_token.span.to(self.token.span),
+                span,
                 "replace `enum struct` with",
                 "enum",
                 Applicability::MachineApplicable,
@@ -1307,7 +1305,8 @@ impl<'a> Parser<'a> {
 
         let (variants, _) = self
             .parse_delim_comma_seq(Delimiter::Brace, |p| p.parse_enum_variant())
-            .map_err(|e| {
+            .map_err(|mut e| {
+                e.span_label(id.span, "while parsing this enum");
                 self.recover_stmt();
                 e
             })?;
@@ -1332,7 +1331,8 @@ impl<'a> Parser<'a> {
 
                 let struct_def = if this.check(&token::OpenDelim(Delimiter::Brace)) {
                     // Parse a struct variant.
-                    let (fields, recovered) = this.parse_record_struct_body("struct", false)?;
+                    let (fields, recovered) =
+                        this.parse_record_struct_body("struct", ident.span, false)?;
                     VariantData::Struct(fields, recovered)
                 } else if this.check(&token::OpenDelim(Delimiter::Parenthesis)) {
                     VariantData::Tuple(this.parse_tuple_struct_body()?, DUMMY_NODE_ID)
@@ -1386,17 +1386,23 @@ impl<'a> Parser<'a> {
                 VariantData::Unit(DUMMY_NODE_ID)
             } else {
                 // If we see: `struct Foo<T> where T: Copy { ... }`
-                let (fields, recovered) =
-                    self.parse_record_struct_body("struct", generics.where_clause.has_where_token)?;
+                let (fields, recovered) = self.parse_record_struct_body(
+                    "struct",
+                    class_name.span,
+                    generics.where_clause.has_where_token,
+                )?;
                 VariantData::Struct(fields, recovered)
             }
         // No `where` so: `struct Foo<T>;`
         } else if self.eat(&token::Semi) {
             VariantData::Unit(DUMMY_NODE_ID)
         // Record-style struct definition
         } else if self.token == token::OpenDelim(Delimiter::Brace) {
-            let (fields, recovered) =
-                self.parse_record_struct_body("struct", generics.where_clause.has_where_token)?;
+            let (fields, recovered) = self.parse_record_struct_body(
+                "struct",
+                class_name.span,
+                generics.where_clause.has_where_token,
+            )?;
             VariantData::Struct(fields, recovered)
         // Tuple-style struct definition with optional where-clause.
         } else if self.token == token::OpenDelim(Delimiter::Parenthesis) {
@@ -1425,12 +1431,18 @@ impl<'a> Parser<'a> {
 
         let vdata = if self.token.is_keyword(kw::Where) {
             generics.where_clause = self.parse_where_clause()?;
-            let (fields, recovered) =
-                self.parse_record_struct_body("union", generics.where_clause.has_where_token)?;
+            let (fields, recovered) = self.parse_record_struct_body(
+                "union",
+                class_name.span,
+                generics.where_clause.has_where_token,
+            )?;
             VariantData::Struct(fields, recovered)
         } else if self.token == token::OpenDelim(Delimiter::Brace) {
-            let (fields, recovered) =
-                self.parse_record_struct_body("union", generics.where_clause.has_where_token)?;
+            let (fields, recovered) = self.parse_record_struct_body(
+                "union",
+                class_name.span,
+                generics.where_clause.has_where_token,
+            )?;
             VariantData::Struct(fields, recovered)
         } else {
             let token_str = super::token_descr(&self.token);
@@ -1446,6 +1458,7 @@ impl<'a> Parser<'a> {
     fn parse_record_struct_body(
         &mut self,
         adt_ty: &str,
+        ident_span: Span,
         parsed_where: bool,
     ) -> PResult<'a, (Vec<FieldDef>, /* recovered */ bool)> {
         let mut fields = Vec::new();
@@ -1460,6 +1473,7 @@ impl<'a> Parser<'a> {
                 match field {
                     Ok(field) => fields.push(field),
                     Err(mut err) => {
+                        err.span_label(ident_span, format!("while parsing this {adt_ty}"));
                         err.emit();
                         break;
                     }

library/core/src/fmt/mod.rs

@@ -709,12 +709,19 @@ pub use macros::Debug;
 
 /// Format trait for an empty format, `{}`.
 ///
+/// Implementing this trait for a type will automatically implement the
+/// [`ToString`][tostring] trait for the type, allowing the usage
+/// of the [`.to_string()`][tostring_function] method. Prefer implementing
+/// the `Display` trait for a type, rather than [`ToString`][tostring].
+///
 /// `Display` is similar to [`Debug`], but `Display` is for user-facing
 /// output, and so cannot be derived.
 ///
 /// For more information on formatters, see [the module-level documentation][module].
 ///
 /// [module]: ../../std/fmt/index.html
+/// [tostring]: ../../std/string/trait.ToString.html
+/// [tostring_function]: ../../std/string/trait.ToString.html#tymethod.to_string
 ///
 /// # Examples
 ///

library/core/src/option.rs

@@ -834,20 +834,12 @@ impl<T> Option<T> {
     ///
     /// # Examples
     ///
-    /// Converts a string to an integer, turning poorly-formed strings
-    /// into 0 (the default value for integers). [`parse`] converts
-    /// a string to any other type that implements [`FromStr`], returning
-    /// [`None`] on error.
-    ///
     /// ```
-    /// let good_year_from_input = "1909";
-    /// let bad_year_from_input = "190blarg";
-    /// // Result::ok() converts a Result<T> to an Option<T>
-    /// let good_year = good_year_from_input.parse().ok().unwrap_or_default();
-    /// let bad_year = bad_year_from_input.parse().ok().unwrap_or_default();
+    /// let x: Option<u32> = None;
+    /// let y: Option<u32> = Some(12);
     ///
-    /// assert_eq!(1909, good_year);
-    /// assert_eq!(0, bad_year);
+    /// assert_eq!(x.unwrap_or_default(), 0);
+    /// assert_eq!(y.unwrap_or_default(), 12);
     /// ```
     ///
     /// [default value]: Default::default

library/core/src/slice/mod.rs

@@ -2076,7 +2076,7 @@ impl<T> [T] {
         SplitN::new(self.split(pred), n)
     }
 
-    /// Returns an iterator over subslices separated by elements that match
+    /// Returns an iterator over mutable subslices separated by elements that match
     /// `pred`, limited to returning at most `n` items. The matched element is
     /// not contained in the subslices.
     ///

src/librustdoc/html/sources.rs

@@ -274,7 +274,7 @@ pub(crate) fn print_src(
 ) {
     let lines = s.lines().count();
     let mut line_numbers = Buffer::empty_from(buf);
-    line_numbers.write_str("<pre class=\"line-numbers\">");
+    line_numbers.write_str("<pre class=\"src-line-numbers\">");
     match source_context {
         SourceContext::Standalone => {
             for line in 1..=lines {

src/librustdoc/html/static/css/rustdoc.css

@@ -299,15 +299,6 @@ summary {
 
 /* Fix some style changes due to normalize.css 8 */
 
-td,
-th {
-	padding: 0;
-}
-
-table {
-	border-collapse: collapse;
-}
-
 button,
 input,
 optgroup,
@@ -578,7 +569,7 @@ h2.location a {
 	position: relative;
 }
 
-.example-wrap > pre.line-number {
+pre.example-line-numbers {
 	overflow: initial;
 	border: 1px solid;
 	padding: 13px 8px;
@@ -591,15 +582,15 @@ h2.location a {
 	text-decoration: underline;
 }
 
-.line-numbers {
+.src-line-numbers {
 	text-align: right;
 }
-.rustdoc:not(.source) .example-wrap > pre:not(.line-number) {
+.rustdoc:not(.source) .example-wrap > pre:not(.example-line-numbers) {
 	width: 100%;
 	overflow-x: auto;
 }
 
-.rustdoc:not(.source) .example-wrap > pre.line-numbers {
+.rustdoc:not(.source) .example-wrap > pre.src-line-numbers {
 	width: auto;
 	overflow-x: visible;
 }
@@ -612,14 +603,14 @@ h2.location a {
 	text-align: center;
 }
 
-.content > .example-wrap pre.line-numbers {
+.content > .example-wrap pre.src-line-numbers {
 	position: relative;
 	-webkit-user-select: none;
 	-moz-user-select: none;
 	-ms-user-select: none;
 	user-select: none;
 }
-.line-numbers span {
+.src-line-numbers span {
 	cursor: pointer;
 }
 
@@ -695,6 +686,7 @@ pre, .rustdoc.source .example-wrap {
 	width: calc(100% - 2px);
 	overflow-x: auto;
 	display: block;
+	border-collapse: collapse;
 }
 
 .docblock table td {
@@ -2067,7 +2059,7 @@ in storage.js plus the media query with (min-width: 701px)
 	padding-bottom: 0;
 }
 
-.scraped-example:not(.expanded) .code-wrapper pre.line-numbers {
+.scraped-example:not(.expanded) .code-wrapper pre.src-line-numbers {
 	overflow-x: hidden;
 }
 
@@ -2113,12 +2105,12 @@ in storage.js plus the media query with (min-width: 701px)
 	bottom: 0;
 }
 
-.scraped-example .code-wrapper .line-numbers {
+.scraped-example .code-wrapper .src-line-numbers {
 	margin: 0;
 	padding: 14px 0;
 }
 
-.scraped-example .code-wrapper .line-numbers span {
+.scraped-example .code-wrapper .src-line-numbers span {
 	padding: 0 14px;
 }
 

src/librustdoc/html/static/css/themes/ayu.css

@@ -93,8 +93,8 @@ pre, .rustdoc.source .example-wrap {
 	color: #ff7733;
 }
 
-.line-numbers span { color: #5c6773; }
-.line-numbers .line-highlighted {
+.src-line-numbers span { color: #5c6773; }
+.src-line-numbers .line-highlighted {
 	color: #708090;
 	background-color: rgba(255, 236, 164, 0.06);
 	padding-right: 4px;
@@ -171,7 +171,7 @@ details.rustdoc-toggle > summary::before {
 	color: #788797;
 }
 
-.line-numbers :target { background-color: transparent; }
+.src-line-numbers :target { background-color: transparent; }
 
 /* Code highlighting */
 pre.rust .number, pre.rust .string { color: #b8cc52; }
@@ -190,7 +190,7 @@ pre.rust .attribute {
 	color: #e6e1cf;
 }
 
-.example-wrap > pre.line-number {
+pre.example-line-numbers {
 	color: #5c67736e;
 	border: none;
 }

src/librustdoc/html/static/css/themes/dark.css

@@ -54,8 +54,8 @@ input:focus + .slider {
 	background: #444;
 }
 
-.line-numbers span { color: #3B91E2; }
-.line-numbers .line-highlighted {
+.src-line-numbers span { color: #3B91E2; }
+.src-line-numbers .line-highlighted {
 	background-color: #0a042f !important;
 }
 
@@ -141,7 +141,7 @@ details.rustdoc-toggle > summary::before {
 	background: none;
 }
 
-.line-numbers :target { background-color: transparent; }
+.src-line-numbers :target { background-color: transparent; }
 
 /* Code highlighting */
 pre.rust .kw { color: #ab8ac1; }
@@ -155,7 +155,7 @@ pre.rust .question-mark {
 	color: #ff9011;
 }
 
-.example-wrap > pre.line-number {
+pre.example-line-numbers {
 	border-color: #4a4949;
 }
 

src/librustdoc/html/static/css/themes/light.css

@@ -53,8 +53,8 @@ input:focus + .slider {
 	background-color: #fff;
 }
 
-.line-numbers span { color: #c67e2d; }
-.line-numbers .line-highlighted {
+.src-line-numbers span { color: #c67e2d; }
+.src-line-numbers .line-highlighted {
 	background-color: #FDFFD3 !important;
 }
 
@@ -125,7 +125,7 @@ body.source .example-wrap pre.rust a {
 .stab { background: #FFF5D6; border-color: #FFC600; }
 .stab.portability > code { background: none; }
 
-.line-numbers :target { background-color: transparent; }
+.src-line-numbers :target { background-color: transparent; }
 
 /* Code highlighting */
 pre.rust .kw { color: #8959A8; }
@@ -141,7 +141,7 @@ pre.rust .question-mark {
 	color: #ff9011;
 }
 
-.example-wrap > pre.line-number {
+pre.example-line-numbers {
 	border-color: #c7c7c7;
 }
 

src/librustdoc/html/static/js/main.js

@@ -699,7 +699,7 @@ function loadCss(cssFileName) {
     window.rustdoc_add_line_numbers_to_examples = () => {
         onEachLazy(document.getElementsByClassName("rust-example-rendered"), x => {
             const parent = x.parentNode;
-            const line_numbers = parent.querySelectorAll(".line-number");
+            const line_numbers = parent.querySelectorAll(".example-line-numbers");
             if (line_numbers.length > 0) {
                 return;
             }
@@ -709,7 +709,7 @@ function loadCss(cssFileName) {
                 elems.push(i + 1);
             }
             const node = document.createElement("pre");
-            addClass(node, "line-number");
+            addClass(node, "example-line-numbers");
             node.innerHTML = elems.join("\n");
             parent.insertBefore(node, x);
         });
@@ -718,7 +718,7 @@ function loadCss(cssFileName) {
     window.rustdoc_remove_line_numbers_from_examples = () => {
         onEachLazy(document.getElementsByClassName("rust-example-rendered"), x => {
             const parent = x.parentNode;
-            const line_numbers = parent.querySelectorAll(".line-number");
+            const line_numbers = parent.querySelectorAll(".example-line-numbers");
             for (const node of line_numbers) {
                 parent.removeChild(node);
             }

src/librustdoc/html/static/js/scrape-examples.js

@@ -8,7 +8,7 @@
 
     // Scroll code block to the given code location
     function scrollToLoc(elt, loc) {
-        const lines = elt.querySelector(".line-numbers");
+        const lines = elt.querySelector(".src-line-numbers");
         let scrollOffset;
 
         // If the block is greater than the size of the viewer,

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

@@ -183,7 +183,7 @@ function highlightSourceLines(match) {
     if (x) {
         x.scrollIntoView();
     }
-    onEachLazy(document.getElementsByClassName("line-numbers"), e => {
+    onEachLazy(document.getElementsByClassName("src-line-numbers"), e => {
         onEachLazy(e.getElementsByTagName("span"), i_e => {
             removeClass(i_e, "line-highlighted");
         });
@@ -245,7 +245,7 @@ window.addEventListener("hashchange", () => {
     }
 });
 
-onEachLazy(document.getElementsByClassName("line-numbers"), el => {
+onEachLazy(document.getElementsByClassName("src-line-numbers"), el => {
     el.addEventListener("click", handleSourceHighlight);
 });