Add new setting to wrap source code lines when too long

4 files changed, 99 insertions, 61 deletions

diff --git a/src/librustdoc/html/static/css/rustdoc.css b/src/librustdoc/html/static/css/rustdoc.css
index 4f5f8f92264..8e904c6200e 100644
--- a/src/librustdoc/html/static/css/rustdoc.css
+++ b/src/librustdoc/html/static/css/rustdoc.css
@@ -41,6 +41,7 @@ xmlns="http://www.w3.org/2000/svg" fill="black" height="18px">\
 	--font-family: "Source Serif 4", NanumBarunGothic, serif;
 	--font-family-code: "Source Code Pro", monospace;
 	--line-number-padding: 4px;
+	--line-number-right-margin: 20px;
 	/* scraped examples icons (34x33px) */
 	--prev-arrow-image: url('data:image/svg+xml,<svg width="16" height="16" viewBox="0 0 16 16" \
 	enable-background="new 0 0 16 16" xmlns="http://www.w3.org/2000/svg"><path fill="none" \
@@ -848,22 +849,6 @@ ul.block, .block li, .block ul {
 	border-radius: 6px;
 }
 
-/*
-If the code example line numbers are displayed, there will be a weird radius in the middle from
-both the code example and the line numbers, so we need to remove the radius in this case.
-*/
-.rustdoc .example-wrap > .example-line-numbers,
-.rustdoc .scraped-example .src-line-numbers,
-.rustdoc .scraped-example .src-line-numbers > pre {
-	border-top-right-radius: 0;
-	border-bottom-right-radius: 0;
-}
-.rustdoc .example-wrap > .example-line-numbers + pre,
-.rustdoc .scraped-example .rust {
-	border-top-left-radius: 0;
-	border-bottom-left-radius: 0;
-}
-
 .rustdoc .scraped-example {
 	position: relative;
 }
@@ -908,45 +893,31 @@ both the code example and the line numbers, so we need to remove the radius in t
 	overflow: auto;
 }
 
-.rustdoc .example-wrap pre.example-line-numbers,
-.rustdoc .example-wrap .src-line-numbers {
-	min-width: fit-content; /* prevent collapsing into nothing in truncated scraped examples */
-	flex-grow: 0;
-	text-align: right;
-	-moz-user-select: none;
-	-webkit-user-select: none;
-	-ms-user-select: none;
-	user-select: none;
-	padding: 14px 8px;
-	padding-right: 2px;
-	color: var(--src-line-numbers-span-color);
-}
-
-.example-wrap.digits-1 [data-nosnippet] {
+.example-wrap.digits-1:not(.hide-lines) [data-nosnippet] {
 	width: calc(1ch + var(--line-number-padding) * 2);
 }
-.example-wrap.digits-2 [data-nosnippet] {
+.example-wrap.digits-2:not(.hide-lines) [data-nosnippet] {
 	width: calc(2ch + var(--line-number-padding) * 2);
 }
-.example-wrap.digits-3 [data-nosnippet] {
+.example-wrap.digits-3:not(.hide-lines) [data-nosnippet] {
 	width: calc(3ch + var(--line-number-padding) * 2);
 }
-.example-wrap.digits-4 [data-nosnippet] {
+.example-wrap.digits-4:not(.hide-lines) [data-nosnippet] {
 	width: calc(4ch + var(--line-number-padding) * 2);
 }
-.example-wrap.digits-5 [data-nosnippet] {
+.example-wrap.digits-5:not(.hide-lines) [data-nosnippet] {
 	width: calc(5ch + var(--line-number-padding) * 2);
 }
-.example-wrap.digits-6 [data-nosnippet] {
+.example-wrap.digits-6:not(.hide-lines) [data-nosnippet] {
 	width: calc(6ch + var(--line-number-padding) * 2);
 }
-.example-wrap.digits-7 [data-nosnippet] {
+.example-wrap.digits-7:not(.hide-lines) [data-nosnippet] {
 	width: calc(7ch + var(--line-number-padding) * 2);
 }
-.example-wrap.digits-8 [data-nosnippet] {
+.example-wrap.digits-8:not(.hide-lines) [data-nosnippet] {
 	width: calc(8ch + var(--line-number-padding) * 2);
 }
-.example-wrap.digits-9 [data-nosnippet] {
+.example-wrap.digits-9:not(.hide-lines) [data-nosnippet] {
 	width: calc(9ch + var(--line-number-padding) * 2);
 }
 
@@ -954,12 +925,12 @@ both the code example and the line numbers, so we need to remove the radius in t
 	color: var(--src-line-numbers-span-color);
 	text-align: right;
 	display: inline-block;
-	margin-right: 20px;
+	margin-right: var(--line-number-right-margin);
 	-moz-user-select: none;
 	-webkit-user-select: none;
 	-ms-user-select: none;
 	user-select: none;
-	padding: 0 4px;
+	padding: 0 var(--line-number-padding);
 }
 .example-wrap [data-nosnippet]:target {
 	border-right: none;
@@ -967,6 +938,60 @@ both the code example and the line numbers, so we need to remove the radius in t
 .example-wrap .line-highlighted[data-nosnippet] {
 	background-color: var(--src-line-number-highlighted-background-color);
 }
+:root.wrap-source-code .example-wrap [data-nosnippet] {
+	position: absolute;
+	left: 0;
+}
+.wrap-source-code .example-wrap pre > code {
+	position: relative;
+	word-break: break-all;
+}
+:root.wrap-source-code .example-wrap pre > code {
+	display: block;
+	white-space: pre-wrap;
+}
+:root.wrap-source-code .example-wrap pre > code * {
+	word-break: break-all;
+}
+:root.wrap-source-code .example-wrap.digits-1 pre > code {
+	padding-left: calc(
+		1ch + var(--line-number-padding) * 2 + var(--line-number-right-margin));
+}
+:root.wrap-source-code .example-wrap.digits-2 pre > code {
+	padding-left: calc(
+		2ch + var(--line-number-padding) * 2 + var(--line-number-right-margin));
+}
+:root.wrap-source-code .example-wrap.digits-3 pre > code {
+	padding-left: calc(
+		3ch + var(--line-number-padding) * 2 + var(--line-number-right-margin));
+}
+:root.wrap-source-code .example-wrap.digits-4 pre > code {
+	padding-left: calc(
+		4ch + var(--line-number-padding) * 2 + var(--line-number-right-margin));
+}
+:root.wrap-source-code .example-wrap.digits-5 pre > code {
+	padding-left: calc(
+		5ch + var(--line-number-padding) * 2 + var(--line-number-right-margin));
+}
+:root.wrap-source-code .example-wrap.digits-6 pre > code {
+	padding-left: calc(
+		6ch + var(--line-number-padding) * 2 + var(--line-number-right-margin));
+}
+:root.wrap-source-code .example-wrap.digits-7 pre > code {
+	padding-left: calc(
+		7ch + var(--line-number-padding) * 2 + var(--line-number-right-margin));
+}
+:root.wrap-source-code .example-wrap.digits-8 pre > code {
+	padding-left: calc(
+		8ch + var(--line-number-padding) * 2 + var(--line-number-right-margin));
+}
+:root.wrap-source-code .example-wrap.digits-9 pre > code {
+	padding-left: calc(
+		9ch + var(--line-number-padding) * 2 + var(--line-number-right-margin));
+}
+.example-wrap.hide-lines [data-nosnippet] {
+	display: none;
+}
 
 .search-loading {
 	text-align: center;
diff --git a/src/librustdoc/html/static/js/main.js b/src/librustdoc/html/static/js/main.js
index a348c6c5678..67cc48f4cb2 100644
--- a/src/librustdoc/html/static/js/main.js
+++ b/src/librustdoc/html/static/js/main.js
@@ -1112,35 +1112,32 @@ function preLoadCss(cssUrl) {
 
     // @ts-expect-error
     window.rustdoc_add_line_numbers_to_examples = () => {
-        if (document.querySelector(".rustdoc.src")) {
-            // We are in the source code page, nothing to be done here!
-            return;
+        // @ts-expect-error
+        function generateLine(nb) {
+            return `<span data-nosnippet>${nb}</span>`;
         }
+
         onEachLazy(document.querySelectorAll(
-            ":not(.scraped-example) > .example-wrap > pre:not(.example-line-numbers)",
-        ), x => {
-            const parent = x.parentNode;
-            const line_numbers = parent.querySelectorAll(".example-line-numbers");
-            if (line_numbers.length > 0) {
+            ".rustdoc:not(.src) :not(.scraped-example) > .example-wrap > pre > code",
+        ), code => {
+            if (hasClass(code.parentElement.parentElement, "hide-lines")) {
+                removeClass(code.parentElement.parentElement, "hide-lines");
                 return;
             }
-            const count = x.textContent.split("\n").length;
-            const elems = [];
-            for (let i = 0; i < count; ++i) {
-                elems.push(i + 1);
-            }
-            const node = document.createElement("pre");
-            addClass(node, "example-line-numbers");
-            node.innerHTML = elems.join("\n");
-            parent.insertBefore(node, x);
+            const lines = code.innerHTML.split("\n");
+            const digits = (lines.length + "").length;
+            // @ts-expect-error
+            code.innerHTML = lines.map((line, index) => generateLine(index + 1) + line).join("\n");
+            addClass(code.parentElement.parentElement, `digits-${digits}`);
         });
     };
 
     // @ts-expect-error
     window.rustdoc_remove_line_numbers_from_examples = () => {
-        onEachLazy(document.querySelectorAll(".example-wrap > .example-line-numbers"), x => {
-            x.parentNode.removeChild(x);
-        });
+        onEachLazy(
+            document.querySelectorAll(".rustdoc:not(.src) :not(.scraped-example) > .example-wrap"),
+            x => addClass(x, "hide-lines"),
+        );
     };
 
     if (getSettingValue("line-numbers") === "true") {
diff --git a/src/librustdoc/html/static/js/settings.js b/src/librustdoc/html/static/js/settings.js
index bf33e0f17e5..2cf6d6fde8f 100644
--- a/src/librustdoc/html/static/js/settings.js
+++ b/src/librustdoc/html/static/js/settings.js
@@ -59,6 +59,14 @@
                 } else {
                     removeClass(document.documentElement, "sans-serif");
                 }
+                break;
+            case "wrap-source-code":
+                if (value === true) {
+                    addClass(document.documentElement, "wrap-source-code");
+                } else {
+                    removeClass(document.documentElement, "wrap-source-code");
+                }
+                break;
         }
     }
 
@@ -246,6 +254,11 @@
                 "js_name": "sans-serif-fonts",
                 "default": false,
             },
+            {
+                "name": "Wrap source codes",
+                "js_name": "wrap-source-code",
+                "default": false,
+            },
         ];
 
         // Then we build the DOM.
diff --git a/src/librustdoc/html/static/js/storage.js b/src/librustdoc/html/static/js/storage.js
index 3042373fb09..4f70166848c 100644
--- a/src/librustdoc/html/static/js/storage.js
+++ b/src/librustdoc/html/static/js/storage.js
@@ -286,6 +286,9 @@ if (getSettingValue("hide-modnav") === "true") {
 if (getSettingValue("sans-serif-fonts") === "true") {
     addClass(document.documentElement, "sans-serif");
 }
+if (getSettingValue("wrap-source-code") === "true") {
+    addClass(document.documentElement, "wrap-source-code");
+}
 function updateSidebarWidth() {
     const desktopSidebarWidth = getSettingValue("desktop-sidebar-width");
     if (desktopSidebarWidth && desktopSidebarWidth !== "null") {