rustdoc: split toolbar when screen is small

src/librustdoc/html/layout.rs

@@ -25,6 +25,7 @@ pub(crate) struct Layout {
 
 pub(crate) struct Page<'a> {
     pub(crate) title: &'a str,
+    pub(crate) short_title: &'a str,
     pub(crate) css_class: &'a str,
     pub(crate) root_path: &'a str,
     pub(crate) static_root_path: Option<&'a str>,

src/librustdoc/html/render/context.rs

@@ -191,6 +191,18 @@ impl<'tcx> Context<'tcx> {
         if !is_module {
             title.push_str(it.name.unwrap().as_str());
         }
+        let short_title;
+        let short_title = if is_module {
+            let module_name = self.current.last().unwrap();
+            short_title = if it.is_crate() {
+                format!("Crate {module_name}")
+            } else {
+                format!("Module {module_name}")
+            };
+            &short_title[..]
+        } else {
+            it.name.as_ref().unwrap().as_str()
+        };
         if !it.is_primitive() && !it.is_keyword() {
             if !is_module {
                 title.push_str(" in ");
@@ -227,6 +239,7 @@ impl<'tcx> Context<'tcx> {
                 root_path: &self.root_path(),
                 static_root_path: clone_shared.static_root_path.as_deref(),
                 title: &title,
+                short_title,
                 description: &desc,
                 resource_suffix: &clone_shared.resource_suffix,
                 rust_logo: has_doc_flag(self.tcx(), LOCAL_CRATE.as_def_id(), sym::rust_logo),
@@ -610,6 +623,7 @@ impl<'tcx> FormatRenderer<'tcx> for Context<'tcx> {
         let shared = Rc::clone(&self.shared);
         let mut page = layout::Page {
             title: "List of all items in this crate",
+            short_title: "All",
             css_class: "mod sys",
             root_path: "../",
             static_root_path: shared.static_root_path.as_deref(),

src/librustdoc/html/render/print_item.rs

@@ -36,6 +36,7 @@ use crate::html::format::{
     print_constness_with_space, print_where_clause, visibility_print_with_space,
 };
 use crate::html::markdown::{HeadingOffset, MarkdownSummaryLine};
+use crate::html::render::sidebar::filters;
 use crate::html::render::{document_full, document_item_info};
 use crate::html::url_parts_builder::UrlPartsBuilder;
 

src/librustdoc/html/render/write_shared.rs

@@ -427,6 +427,7 @@ impl CratesIndexPart {
     fn blank(cx: &Context<'_>) -> SortedTemplate<<Self as CciPart>::FileFormat> {
         let page = layout::Page {
             title: "Index of crates",
+            short_title: "Crates",
             css_class: "mod sys",
             root_path: "./",
             static_root_path: cx.shared.static_root_path.as_deref(),

src/librustdoc/html/sources.rs

@@ -238,6 +238,7 @@ impl SourceCollector<'_, '_> {
             format!("Source of the Rust file `{}`.", filename.prefer_remapped_unconditionaly());
         let page = layout::Page {
             title: &title,
+            short_title: &src_fname.to_string_lossy(),
             css_class: "src",
             root_path: &root_path,
             static_root_path: shared.static_root_path.as_deref(),