diff --git a/src/librustdoc/clean/mod.rs b/src/librustdoc/clean/mod.rs
index 6160783f652f1..2c63f381851f4 100644
--- a/src/librustdoc/clean/mod.rs
+++ b/src/librustdoc/clean/mod.rs
@@ -1991,6 +1991,7 @@ fn clean_maybe_renamed_item<'tcx>(
ItemKind::Trait(_, _, generics, bounds, item_ids) => {
let items =
item_ids.iter().map(|ti| cx.tcx.hir().trait_item(ti.id).clean(cx)).collect();
+
TraitItem(Trait {
def_id,
items,
diff --git a/src/librustdoc/html/render/print_item.rs b/src/librustdoc/html/render/print_item.rs
index 81cc12c9d5596..dcd2eaac7ea60 100644
--- 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_middle::ty::{Adt, TyCtxt};
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::markdown::{HeadingOffset, MarkdownSummaryLine};
use crate::html::url_parts_builder::UrlPartsBuilder;
use askama::Template;
+use itertools::Itertools;
const ITEM_TABLE_OPEN: &str = "
";
const ITEM_TABLE_CLOSE: &str = "
";
@@ -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 item_trait(w: &mut Buffer, cx: &mut Context<'_>, it: &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",
"",
);
+
+ if let Some(list) = must_implement_one_of_functions.as_deref() {
+ write!(
+ w,
+ "
At least one of the `{}` methods is required.
",
+ list.iter().join("`, `")
+ );
+ }
+
for m in required_methods {
trait_item(w, cx, m, it);
}
diff --git a/src/librustdoc/html/static/css/themes/ayu.css b/src/librustdoc/html/static/css/themes/ayu.css
index 7ff8063904ace..c42cac59bd6fa 100644
--- a/src/librustdoc/html/static/css/themes/ayu.css
+++ b/src/librustdoc/html/static/css/themes/ayu.css
@@ -205,11 +205,13 @@ details.rustdoc-toggle > summary::before {
/* Created this empty rule to satisfy the theme checks. */
.stab.empty-impl {}
+.stab.must_implement {}
.stab.unstable,
.stab.deprecated,
.stab.portability,
-.stab.empty-impl {
+.stab.empty-impl,
+.stab.must_implement {
color: #c5c5c5;
background: #314559 !important;
border-style: none !important;
diff --git a/src/librustdoc/html/static/css/themes/dark.css b/src/librustdoc/html/static/css/themes/dark.css
index 8e753f5768206..62d9eaa02e6a7 100644
--- a/src/librustdoc/html/static/css/themes/dark.css
+++ b/src/librustdoc/html/static/css/themes/dark.css
@@ -180,6 +180,7 @@ details.rustdoc-toggle > summary::before {
.stab.empty-impl { background: #FFF5D6; border-color: #FFC600; color: #2f2f2f; }
.stab.unstable { background: #FFF5D6; border-color: #FFC600; color: #2f2f2f; }
.stab.deprecated { background: #ffc4c4; border-color: #db7b7b; color: #2f2f2f; }
+.stab.must_implement { background: #F3DFFF; border-color: #b07bdb; color: #2f2f2f; }
.stab.portability { background: #F3DFFF; border-color: #b07bdb; color: #2f2f2f; }
.stab.portability > code { background: none; }
diff --git a/src/librustdoc/html/static/css/themes/light.css b/src/librustdoc/html/static/css/themes/light.css
index 40d965c39c390..b751acff152cb 100644
--- a/src/librustdoc/html/static/css/themes/light.css
+++ b/src/librustdoc/html/static/css/themes/light.css
@@ -163,6 +163,7 @@ details.rustdoc-toggle > summary::before {
.stab.empty-impl { background: #FFF5D6; border-color: #FFC600; }
.stab.unstable { background: #FFF5D6; border-color: #FFC600; }
.stab.deprecated { background: #ffc4c4; border-color: #db7b7b; }
+.stab.must_implement { background: #F3DFFF; border-color: #b07bdb; }
.stab.portability { background: #F3DFFF; border-color: #b07bdb; }
.stab.portability > code { background: none; }
diff --git a/src/test/rustdoc/must_implement_one_of.rs b/src/test/rustdoc/must_implement_one_of.rs
new file mode 100644
index 0000000000000..1f1dd5d5796ee
--- /dev/null
+++ b/src/test/rustdoc/must_implement_one_of.rs
@@ -0,0 +1,10 @@
+#![crate_name = "c"]
+#![feature(rustc_attrs)]
+
+#[rustc_must_implement_one_of(a, b)]
+// @matches c/trait.Trait.html '//*[@class="stab must_implement"]' \
+// 'At least one of the `a`, `b` methods is required.$'
+pub trait Trait {
+ fn a() {}
+ fn b() {}
+}