From 7a5cd2be84623011dd7d4d77e510a39d7c8bf657 Mon Sep 17 00:00:00 2001
From: Jacob Hoffman-Andrews <github@hoffman-andrews.com>
Date: Tue, 23 Nov 2021 21:23:54 -0800
Subject: [PATCH] Consistentize the system for image URLs in CSS.

---
 src/librustdoc/html/render/write_shared.rs | 48 +++++++++-------------
 src/librustdoc/html/static/css/rustdoc.css | 11 +++++
 src/librustdoc/html/templates/page.html    |  5 ---
 3 files changed, 31 insertions(+), 33 deletions(-)

diff --git a/src/librustdoc/html/render/write_shared.rs b/src/librustdoc/html/render/write_shared.rs
index cbb5755863613..0d5ba8e80d242 100644
--- a/src/librustdoc/html/render/write_shared.rs
+++ b/src/librustdoc/html/render/write_shared.rs
@@ -181,42 +181,34 @@ pub(super) fn write_shared(
         cx.write_shared(SharedResource::InvocationSpecific { basename: p }, content, &options.emit)
     };
 
-    fn add_background_image_to_css(
-        cx: &Context<'_>,
-        css: &mut String,
-        rule: &str,
-        file: &'static str,
-    ) {
-        css.push_str(&format!(
-            "{} {{ background-image: url({}); }}",
-            rule,
-            SharedResource::ToolchainSpecific { basename: file }
+    // Given "foo.svg", return e.g. "url(\"foo1.58.0.svg\")"
+    fn ver_url(cx: &Context<'_>, basename: &'static str) -> String {
+        format!(
+            "url(\"{}\")",
+            SharedResource::ToolchainSpecific { basename }
                 .path(cx)
                 .file_name()
                 .unwrap()
                 .to_str()
                 .unwrap()
-        ))
+        )
     }
 
-    // Add all the static files. These may already exist, but we just
-    // overwrite them anyway to make sure that they're fresh and up-to-date.
-    let mut rustdoc_css = static_files::RUSTDOC_CSS.to_owned();
-    add_background_image_to_css(
-        cx,
-        &mut rustdoc_css,
-        "details.undocumented[open] > summary::before, \
-         details.rustdoc-toggle[open] > summary::before, \
-         details.rustdoc-toggle[open] > summary.hideme::before",
-        "toggle-minus.svg",
-    );
-    add_background_image_to_css(
+    // We use the AUTOREPLACE mechanism to inject into our static JS and CSS certain
+    // values that are only known at doc build time. Since this mechanism is somewhat
+    // surprising when reading the code, please limit it to rustdoc.css.
+    write_minify(
+        "rustdoc.css",
+        static_files::RUSTDOC_CSS
+            .replace(
+                "/* AUTOREPLACE: */url(\"toggle-minus.svg\")",
+                &ver_url(cx, "toggle-minus.svg"),
+            )
+            .replace("/* AUTOREPLACE: */url(\"toggle-plus.svg\")", &ver_url(cx, "toggle-plus.svg"))
+            .replace("/* AUTOREPLACE: */url(\"down-arrow.svg\")", &ver_url(cx, "down-arrow.svg")),
         cx,
-        &mut rustdoc_css,
-        "details.undocumented > summary::before, details.rustdoc-toggle > summary::before",
-        "toggle-plus.svg",
-    );
-    write_minify("rustdoc.css", rustdoc_css, cx, options)?;
+        options,
+    )?;
 
     // Add all the static files. These may already exist, but we just
     // overwrite them anyway to make sure that they're fresh and up-to-date.
diff --git a/src/librustdoc/html/static/css/rustdoc.css b/src/librustdoc/html/static/css/rustdoc.css
index 89a763ef6d707..fbc26fb55d3b3 100644
--- a/src/librustdoc/html/static/css/rustdoc.css
+++ b/src/librustdoc/html/static/css/rustdoc.css
@@ -825,6 +825,7 @@ h2.small-section-header > .anchor {
 	background-color: transparent;
 	background-size: 20px;
 	background-position: calc(100% - 1px) 56%;
+	background-image: /* AUTOREPLACE: */url("down-arrow.svg");
 }
 .search-container > .top-button {
 	position: absolute;
@@ -1611,6 +1612,16 @@ details.rustdoc-toggle[open] > summary.hideme > span {
 	display: none;
 }
 
+details.undocumented[open] > summary::before,
+details.rustdoc-toggle[open] > summary::before,
+details.rustdoc-toggle[open] > summary.hideme::before {
+	background-image: /* AUTOREPLACE: */url("toggle-minus.svg");
+}
+
+details.undocumented > summary::before, details.rustdoc-toggle > summary::before {
+	background-image: /* AUTOREPLACE: */url("toggle-plus.svg");
+}
+
 details.rustdoc-toggle[open] > summary::before,
 details.rustdoc-toggle[open] > summary.hideme::before {
 	width: 17px;
diff --git a/src/librustdoc/html/templates/page.html b/src/librustdoc/html/templates/page.html
index e1a9a01588673..2c81dca3891c5 100644
--- a/src/librustdoc/html/templates/page.html
+++ b/src/librustdoc/html/templates/page.html
@@ -48,11 +48,6 @@
             href="{{static_root_path | safe}}favicon{{page.resource_suffix}}.svg"> {#- -#}
     {%- endif -%}
     {{- layout.external_html.in_header | safe -}}
-    <style type="text/css"> {#- -#}
-    #crate-search{ {#- -#}
-        background-image:url("{{static_root_path | safe}}down-arrow{{page.resource_suffix}}.svg"); {#- -#}
-    } {#- -#}
-    </style> {#- -#}
 </head> {#- -#}
 <body class="rustdoc {{page.css_class}}"> {#- -#}
     <!--[if lte IE 11]> {#- -#}