Rollup merge of #99079 - compiler-errors:issue-99073, r=oli-obk

[rust.git] / src / librustdoc / html / render / print_item.rs

diff --git a/src/librustdoc/html/render/print_item.rs b/src/librustdoc/html/render/print_item.rs
index 81cc12c9d55961dc23407e07c9488d00ee6ec7d2..69d66693f752e92b9528917f15f82aad73c22696 100644 (file)
--- a/src/librustdoc/html/render/print_item.rs
+++ b/src/librustdoc/html/render/print_item.rs
@@ -1,9 +1,5 @@
 use clean::AttributesExt;
 
-use std::cmp::Ordering;
-use std::fmt;
-use std::rc::Rc;
-
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_hir as hir;
 use rustc_hir::def::CtorKind;
@@ -15,6 +11,9 @@
 use rustc_span::hygiene::MacroKind;
 use rustc_span::symbol::{kw, sym, Symbol};
 use rustc_target::abi::{Layout, Primitive, TagEncoding, Variants};
+use std::cmp::Ordering;
+use std::fmt;
+use std::rc::Rc;
 
 use super::{
     collect_paths_for_type, document, ensure_trailing_slash, item_ty_to_section,
@@ -37,6 +36,7 @@
 use crate::html::url_parts_builder::UrlPartsBuilder;
 
 use askama::Template;
+use itertools::Itertools;
 
 const ITEM_TABLE_OPEN: &str = "<div class=\"item-table\">";
 const ITEM_TABLE_CLOSE: &str = "</div>";
@@ -539,6 +539,8 @@ fn item_trait(w: &mut Buffer, cx: &mut Context<'_>, it: &clean::Item, t: &clean:
     let count_types = required_types.len() + provided_types.len();
     let count_consts = required_consts.len() + provided_consts.len();
     let count_methods = required_methods.len() + provided_methods.len();
+    let must_implement_one_of_functions =
+        cx.tcx().trait_def(t.def_id).must_implement_one_of.clone();
 
     // Output the trait definition
     wrap_into_docblock(w, |w| {
@@ -784,13 +786,22 @@ fn trait_item(w: &mut Buffer, cx: &mut Context<'_>, m: &clean::Item, t: &clean::
     }
 
     // Output the documentation for each function individually
-    if !required_methods.is_empty() {
+    if !required_methods.is_empty() || must_implement_one_of_functions.is_some() {
         write_small_section_header(
             w,
             "required-methods",
             "Required Methods",
             "<div class=\"methods\">",
         );
+
+        if let Some(list) = must_implement_one_of_functions.as_deref() {
+            write!(
+                w,
+                "<div class=\"stab must_implement\">At least one of the `{}` methods is required.</div>",
+                list.iter().join("`, `")
+            );
+        }
+
         for m in required_methods {
             trait_item(w, cx, m, it);
         }
@@ -1869,7 +1880,11 @@ fn write_size_of_layout(w: &mut Buffer, layout: Layout<'_>, tag_size: u64) {
         return;
     }
 
-    writeln!(w, "<h2 class=\"small-section-header\">Layout</h2>");
+    writeln!(
+        w,
+        "<h2 id=\"layout\" class=\"small-section-header\"> \
+        Layout<a href=\"#layout\" class=\"anchor\"></a></h2>"
+    );
     writeln!(w, "<div class=\"docblock\">");
 
     let tcx = cx.tcx();