Open trait implementations' toggles by default.

This makes it possible to use Ctrl-F to find methods defined in traits.

Author: jsha

src/librustdoc/html/render/mod.rs

@@ -488,7 +488,7 @@ fn settings(root_path: &str, suffix: &str, themes: &[StylePath]) -> Result<Strin
             .into(),
         ("auto-hide-large-items", "Auto-hide item contents for large items.", true).into(),
         ("auto-hide-method-docs", "Auto-hide item methods' documentation", false).into(),
-        ("auto-hide-trait-implementations", "Auto-hide trait implementation documentation", true)
+        ("auto-hide-trait-implementations", "Auto-hide trait implementation documentation", false)
             .into(),
         ("auto-collapse-implementors", "Auto-hide implementors of a trait", true).into(),
         ("go-to-only-result", "Directly go to item in search if there is only one result", false)
@@ -1543,15 +1543,10 @@ fn render_impl(
         }
     }
     if render_mode == RenderMode::Normal {
-        let is_implementing_trait = i.inner_impl().trait_.is_some();
         let toggled = !impl_items.is_empty() || !default_impl_items.is_empty();
         if toggled {
             close_tags.insert_str(0, "</details>");
-            if is_implementing_trait {
-                write!(w, "<details class=\"rustdoc-toggle implementors-toggle\">");
-            } else {
-                write!(w, "<details class=\"rustdoc-toggle implementors-toggle\" open>");
-            }
+            write!(w, "<details class=\"rustdoc-toggle implementors-toggle\" open>");
         }
         if toggled {
             write!(w, "<summary>")

src/librustdoc/html/static/main.js

@@ -779,25 +779,25 @@ function hideThemeButtonState() {
 
         var hideMethodDocs = getSettingValue("auto-hide-method-docs") === "true";
         var hideImplementors = getSettingValue("auto-collapse-implementors") !== "false";
-        var hideImplementations = getSettingValue("auto-hide-trait-implementations") !== "false";
+        var hideImplementations = getSettingValue("auto-hide-trait-implementations") === "true";
         var hideLargeItemContents = getSettingValue("auto-hide-large-items") !== "false";
 
-        function openImplementors(id) {
+        function setImplementorsTogglesOpen(id, open) {
             var list = document.getElementById(id);
             if (list !== null) {
                 onEachLazy(list.getElementsByClassName("implementors-toggle"), function(e) {
-                    e.open = true;
+                    e.open = open;
                 });
             }
         }
 
-        if (!hideImplementations) {
-            openImplementors("trait-implementations-list");
-            openImplementors("blanket-implementations-list");
+        if (hideImplementations) {
+            setImplementorsTogglesOpen("trait-implementations-list", false);
+            setImplementorsTogglesOpen("blanket-implementations-list", false);
         }
 
         if (!hideImplementors) {
-            openImplementors("implementors-list");
+            setImplementorsTogglesOpen("implementors-list", true);
         }
 
         onEachLazy(document.getElementsByClassName("rustdoc-toggle"), function (e) {

src/test/rustdoc-gui/toggled-open-implementations.goml

@@ -0,0 +1,5 @@
+// This tests that the "implementations" section on struct/enum pages
+// has all the implementations toggled open by default, so users can
+// find method names in those implementations with Ctrl-F.
+goto: file://|DOC_PATH|/test_docs/struct.Foo.html
+assert: (".rustdoc-toggle.implementors-toggle", "open", "")