From 7a718f3be217a17e00de317fba6d1d60facfd613 Mon Sep 17 00:00:00 2001
From: Michael Howell <michael@notriddle.com>
Date: Wed, 21 Sep 2022 15:26:15 -0700
Subject: [PATCH 1/3] rustdoc: use block flex for line-number CSS

`display: inline-flex` was used as part of
e961d397cab900c55f8d8c104648852e2b63664e, the original commit that added
these line numbers. Does anyone know why it was done this way?
---
 src/librustdoc/html/static/css/rustdoc.css | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/src/librustdoc/html/static/css/rustdoc.css b/src/librustdoc/html/static/css/rustdoc.css
index e985e6c43ad..1d37c4f60d0 100644
--- a/src/librustdoc/html/static/css/rustdoc.css
+++ b/src/librustdoc/html/static/css/rustdoc.css
@@ -577,13 +577,9 @@ h2.location a {
 }
 
 .rustdoc .example-wrap {
-	display: inline-flex;
+	display: flex;
 	margin-bottom: 10px;
-}
-
-.example-wrap {
 	position: relative;
-	width: 100%;
 }
 
 .example-wrap > pre.line-number {

From f66769fe8d71d9d5d15f845e6ef918f2e417598f Mon Sep 17 00:00:00 2001
From: Michael Howell <michael@notriddle.com>
Date: Wed, 21 Sep 2022 15:43:38 -0700
Subject: [PATCH 2/3] rustdoc: dynamically show-hide line numbers on code
 examples

---
 src/librustdoc/html/static/js/main.js         | 41 ++++++++++++++-----
 src/librustdoc/html/static/js/settings.js     |  7 ++++
 .../docblock-code-block-line-number.goml      | 17 ++++++++
 3 files changed, 54 insertions(+), 11 deletions(-)

diff --git a/src/librustdoc/html/static/js/main.js b/src/librustdoc/html/static/js/main.js
index 6e9660ddcc9..5fbe540c320 100644
--- a/src/librustdoc/html/static/js/main.js
+++ b/src/librustdoc/html/static/js/main.js
@@ -697,20 +697,39 @@ function loadCss(cssFileName) {
         }
     }());
 
+    window.rustdoc_add_line_numbers_to_examples = () => {
+        onEachLazy(document.getElementsByClassName("rust-example-rendered"), x => {
+            const parent = x.parentNode;
+            const line_numbers = parent.querySelectorAll(".line-number");
+            if (line_numbers.length > 0) {
+                return;
+            }
+            const count = x.textContent.split("\n").length;
+            const elems = [];
+            for (let i = 0; i < count; ++i) {
+                elems.push(i + 1);
+            }
+            const node = document.createElement("pre");
+            addClass(node, "line-number");
+            node.innerHTML = elems.join("\n");
+            parent.insertBefore(node, x);
+        });
+    };
+
+    window.rustdoc_remove_line_numbers_from_examples = () => {
+        onEachLazy(document.getElementsByClassName("rust-example-rendered"), x => {
+            const parent = x.parentNode;
+            const line_numbers = parent.querySelectorAll(".line-number");
+            for (const node of line_numbers) {
+                parent.removeChild(node);
+            }
+        });
+    };
+
     (function() {
         // To avoid checking on "rustdoc-line-numbers" value on every loop...
         if (getSettingValue("line-numbers") === "true") {
-            onEachLazy(document.getElementsByClassName("rust-example-rendered"), x => {
-                const count = x.textContent.split("\n").length;
-                const elems = [];
-                for (let i = 0; i < count; ++i) {
-                    elems.push(i + 1);
-                }
-                const node = document.createElement("pre");
-                addClass(node, "line-number");
-                node.innerHTML = elems.join("\n");
-                x.parentNode.insertBefore(node, x);
-            });
+            window.rustdoc_add_line_numbers_to_examples();
         }
     }());
 
diff --git a/src/librustdoc/html/static/js/settings.js b/src/librustdoc/html/static/js/settings.js
index 797b931afc6..1c5d33e2127 100644
--- a/src/librustdoc/html/static/js/settings.js
+++ b/src/librustdoc/html/static/js/settings.js
@@ -19,6 +19,13 @@
                 updateSystemTheme();
                 updateLightAndDark();
                 break;
+            case "line-numbers":
+                if (value === true) {
+                    window.rustdoc_add_line_numbers_to_examples();
+                } else {
+                    window.rustdoc_remove_line_numbers_from_examples();
+                }
+                break;
         }
     }
 
diff --git a/src/test/rustdoc-gui/docblock-code-block-line-number.goml b/src/test/rustdoc-gui/docblock-code-block-line-number.goml
index baf9651c40d..ebfffbce715 100644
--- a/src/test/rustdoc-gui/docblock-code-block-line-number.goml
+++ b/src/test/rustdoc-gui/docblock-code-block-line-number.goml
@@ -20,3 +20,20 @@ assert-css: ("pre.line-number", {
 })
 // The first code block has two lines so let's check its `<pre>` elements lists both of them.
 assert-text: ("pre.line-number", "1\n2")
+
+// Now, try changing the setting dynamically. We'll turn it off, using the settings menu,
+// and make sure it goes away.
+
+// First, open the settings menu.
+click: "#settings-menu"
+wait-for: "#settings"
+assert-css: ("#settings", {"display": "block"})
+
+// Then, click the toggle button.
+click: "input#line-numbers + .slider"
+wait-for: 100 // wait-for-false does not exist
+assert-false: "pre.line-number"
+
+// Finally, turn it on again.
+click: "input#line-numbers + .slider"
+wait-for: "pre.line-number"

From 8b4c0d90dc403cb9727e80d73c27d4f3de574d60 Mon Sep 17 00:00:00 2001
From: Michael Howell <michael@notriddle.com>
Date: Wed, 21 Sep 2022 16:44:33 -0700
Subject: [PATCH 3/3] rustdoc: adjust test to cope with slightly different
 scrolling behaviour

---
 src/test/rustdoc-gui/source-anchor-scroll.goml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/test/rustdoc-gui/source-anchor-scroll.goml b/src/test/rustdoc-gui/source-anchor-scroll.goml
index 4e51c8dcac0..47e40aa8e3b 100644
--- a/src/test/rustdoc-gui/source-anchor-scroll.goml
+++ b/src/test/rustdoc-gui/source-anchor-scroll.goml
@@ -10,7 +10,7 @@ assert-property: ("html", {"scrollTop": "0"})
 click: '//a[text() = "barbar"]'
 assert-property: ("html", {"scrollTop": "125"})
 click: '//a[text() = "bar"]'
-assert-property: ("html", {"scrollTop": "166"})
+assert-property: ("html", {"scrollTop": "156"})
 click: '//a[text() = "sub_fn"]'
 assert-property: ("html", {"scrollTop": "53"})