Rollup merge of rust-lang#71237 - Cldfire:rustdoc-ayu-theme, r=GuilliaumeGomez

Add Ayu theme to rustdoc

This is a port of a theme I maintain (https://github.com/Cldfire/ayu-rs) to the native rustdoc theme system. [Ayu](https://github.com/dempfi/ayu) (dark) is a richly-colored dark theme that many people enjoy using across a wide variety of environments.

Corresponds to the Ayu theme in [mdBook](https://github.com/rust-lang/mdBook).

Some screenshots:

![image](https://user-images.githubusercontent.com/13814214/79547087-6c935780-8061-11ea-8a33-38e9472e9fec.png)

![image](https://user-images.githubusercontent.com/13814214/79547150-8339ae80-8061-11ea-97be-9e13a8b275d7.png)

![image](https://user-images.githubusercontent.com/13814214/79547221-98164200-8061-11ea-9649-9b11ccbb33e3.png)

![image](https://user-images.githubusercontent.com/13814214/79547310-b419e380-8061-11ea-9965-d4f90b2280ab.png)

![image](https://user-images.githubusercontent.com/13814214/79547443-e7f50900-8061-11ea-8872-06d74010691e.png)

Note that this pull request also makes some small code changes to allow for disabling theme stylesheets, preventing the rules from all the different themes from conflicting with one another. The only stylesheet that is not disabled is `light.css`; the theming system (quite hackily) switches themes by changing the href on this stylesheet and so permanently disabling all the others works perfectly fine.

Author: Dylan-DPC

src/librustdoc/config.rs

@@ -20,6 +20,7 @@ use crate::core::new_handler;
 use crate::externalfiles::ExternalHtml;
 use crate::html;
 use crate::html::markdown::IdMap;
+use crate::html::render::StylePath;
 use crate::html::static_files;
 use crate::opts;
 use crate::passes::{self, Condition, DefaultPassOption};
@@ -207,7 +208,7 @@ pub struct RenderOptions {
     pub sort_modules_alphabetically: bool,
     /// List of themes to extend the docs with. Original argument name is included to assist in
     /// displaying errors if it fails a theme check.
-    pub themes: Vec<PathBuf>,
+    pub themes: Vec<StylePath>,
     /// If present, CSS file that contains rules to add to the default CSS.
     pub extension_css: Option<PathBuf>,
     /// A map of crate names to the URL to use instead of querying the crate's `html_root_url`.
@@ -410,7 +411,7 @@ impl Options {
                     ))
                     .emit();
                 }
-                themes.push(theme_file);
+                themes.push(StylePath { path: theme_file, disabled: true });
             }
         }
 

src/librustdoc/html/layout.rs

@@ -3,7 +3,7 @@ use std::path::PathBuf;
 use crate::externalfiles::ExternalHtml;
 use crate::html::escape::Escape;
 use crate::html::format::{Buffer, Print};
-use crate::html::render::ensure_trailing_slash;
+use crate::html::render::{ensure_trailing_slash, StylePath};
 
 #[derive(Clone)]
 pub struct Layout {
@@ -36,7 +36,7 @@ pub fn render<T: Print, S: Print>(
     page: &Page<'_>,
     sidebar: S,
     t: T,
-    themes: &[PathBuf],
+    style_files: &[StylePath],
 ) -> String {
     let static_root_path = page.static_root_path.unwrap_or(page.root_path);
     format!(
@@ -52,10 +52,7 @@ pub fn render<T: Print, S: Print>(
     <link rel=\"stylesheet\" type=\"text/css\" href=\"{static_root_path}normalize{suffix}.css\">\
     <link rel=\"stylesheet\" type=\"text/css\" href=\"{static_root_path}rustdoc{suffix}.css\" \
           id=\"mainThemeStyle\">\
-    {themes}\
-    <link rel=\"stylesheet\" type=\"text/css\" href=\"{static_root_path}dark{suffix}.css\">\
-    <link rel=\"stylesheet\" type=\"text/css\" href=\"{static_root_path}light{suffix}.css\" \
-          id=\"themeStyle\">\
+    {style_files}\
     <script src=\"{static_root_path}storage{suffix}.js\"></script>\
     <noscript><link rel=\"stylesheet\" href=\"{static_root_path}noscript{suffix}.css\"></noscript>\
     {css_extension}\
@@ -172,13 +169,19 @@ pub fn render<T: Print, S: Print>(
         after_content = layout.external_html.after_content,
         sidebar = Buffer::html().to_display(sidebar),
         krate = layout.krate,
-        themes = themes
+        style_files = style_files
             .iter()
-            .filter_map(|t| t.file_stem())
-            .filter_map(|t| t.to_str())
+            .filter_map(|t| {
+                if let Some(stem) = t.path.file_stem() { Some((stem, t.disabled)) } else { None }
+            })
+            .filter_map(|t| {
+                if let Some(path) = t.0.to_str() { Some((path, t.1)) } else { None }
+            })
             .map(|t| format!(
-                r#"<link rel="stylesheet" type="text/css" href="{}.css">"#,
-                Escape(&format!("{}{}{}", static_root_path, t, page.resource_suffix))
+                r#"<link rel="stylesheet" type="text/css" href="{}.css" {} {}>"#,
+                Escape(&format!("{}{}{}", static_root_path, t.0, page.resource_suffix)),
+                if t.1 { "disabled" } else { "" },
+                if t.0 == "light" { "id=\"themeStyle\"" } else { "" }
             ))
             .collect::<String>(),
         suffix = page.resource_suffix,

src/librustdoc/html/render.rs

@@ -188,8 +188,8 @@ crate struct SharedContext {
     /// This flag indicates whether listings of modules (in the side bar and documentation itself)
     /// should be ordered alphabetically or in order of appearance (in the source code).
     pub sort_modules_alphabetically: bool,
-    /// Additional themes to be added to the generated docs.
-    pub themes: Vec<PathBuf>,
+    /// Additional CSS files to be added to the generated docs.
+    pub style_files: Vec<StylePath>,
     /// Suffix to be added on resource files (if suffix is "-v2" then "light.css" becomes
     /// "light-v2.css").
     pub resource_suffix: String,
@@ -418,6 +418,14 @@ impl Serialize for TypeWithKind {
     }
 }
 
+#[derive(Debug, Clone)]
+pub struct StylePath {
+    /// The path to the theme
+    pub path: PathBuf,
+    /// What the `disabled` attribute should be set to in the HTML tag
+    pub disabled: bool,
+}
+
 thread_local!(static CACHE_KEY: RefCell<Arc<Cache>> = Default::default());
 thread_local!(pub static CURRENT_DEPTH: Cell<usize> = Cell::new(0));
 
@@ -461,7 +469,7 @@ pub fn run(
         id_map,
         playground_url,
         sort_modules_alphabetically,
-        themes,
+        themes: style_files,
         extension_css,
         extern_html_root_urls,
         resource_suffix,
@@ -531,7 +539,7 @@ pub fn run(
         layout,
         created_dirs: Default::default(),
         sort_modules_alphabetically,
-        themes,
+        style_files,
         resource_suffix,
         static_root_path,
         fs: DocFS::new(&errors),
@@ -540,6 +548,19 @@ pub fn run(
         playground,
     };
 
+    // Add the default themes to the `Vec` of stylepaths
+    //
+    // Note that these must be added before `sources::render` is called
+    // so that the resulting source pages are styled
+    //
+    // `light.css` is not disabled because it is the stylesheet that stays loaded
+    // by the browser as the theme stylesheet. The theme system (hackily) works by
+    // changing the href to this stylesheet. All other themes are disabled to
+    // prevent rule conflicts
+    scx.style_files.push(StylePath { path: PathBuf::from("light.css"), disabled: false });
+    scx.style_files.push(StylePath { path: PathBuf::from("dark.css"), disabled: true });
+    scx.style_files.push(StylePath { path: PathBuf::from("ayu.css"), disabled: true });
+
     let dst = output;
     scx.ensure_dir(&dst)?;
     krate = sources::render(&dst, &mut scx, krate)?;
@@ -616,11 +637,40 @@ fn write_shared(
     // then we'll run over the "official" styles.
     let mut themes: FxHashSet<String> = FxHashSet::default();
 
-    for entry in &cx.shared.themes {
-        let content = try_err!(fs::read(&entry), &entry);
-        let theme = try_none!(try_none!(entry.file_stem(), &entry).to_str(), &entry);
-        let extension = try_none!(try_none!(entry.extension(), &entry).to_str(), &entry);
-        cx.shared.fs.write(cx.path(&format!("{}.{}", theme, extension)), content.as_slice())?;
+    for entry in &cx.shared.style_files {
+        let theme = try_none!(try_none!(entry.path.file_stem(), &entry.path).to_str(), &entry.path);
+        let extension =
+            try_none!(try_none!(entry.path.extension(), &entry.path).to_str(), &entry.path);
+
+        // Handle the official themes
+        match theme {
+            "light" => write_minify(
+                &cx.shared.fs,
+                cx.path("light.css"),
+                static_files::themes::LIGHT,
+                options.enable_minification,
+            )?,
+            "dark" => write_minify(
+                &cx.shared.fs,
+                cx.path("dark.css"),
+                static_files::themes::DARK,
+                options.enable_minification,
+            )?,
+            "ayu" => write_minify(
+                &cx.shared.fs,
+                cx.path("ayu.css"),
+                static_files::themes::AYU,
+                options.enable_minification,
+            )?,
+            _ => {
+                // Handle added third-party themes
+                let content = try_err!(fs::read(&entry.path), &entry.path);
+                cx.shared
+                    .fs
+                    .write(cx.path(&format!("{}.{}", theme, extension)), content.as_slice())?;
+            }
+        };
+
         themes.insert(theme.to_owned());
     }
 
@@ -634,20 +684,6 @@ fn write_shared(
     write(cx.path("brush.svg"), static_files::BRUSH_SVG)?;
     write(cx.path("wheel.svg"), static_files::WHEEL_SVG)?;
     write(cx.path("down-arrow.svg"), static_files::DOWN_ARROW_SVG)?;
-    write_minify(
-        &cx.shared.fs,
-        cx.path("light.css"),
-        static_files::themes::LIGHT,
-        options.enable_minification,
-    )?;
-    themes.insert("light".to_owned());
-    write_minify(
-        &cx.shared.fs,
-        cx.path("dark.css"),
-        static_files::themes::DARK,
-        options.enable_minification,
-    )?;
-    themes.insert("dark".to_owned());
 
     let mut themes: Vec<&String> = themes.iter().collect();
     themes.sort();
@@ -958,7 +994,7 @@ themePicker.onblur = handleThemeButtonsBlur;
                     })
                     .collect::<String>()
             );
-            let v = layout::render(&cx.shared.layout, &page, "", content, &cx.shared.themes);
+            let v = layout::render(&cx.shared.layout, &page, "", content, &cx.shared.style_files);
             cx.shared.fs.write(&dst, v.as_bytes())?;
         }
     }
@@ -1376,7 +1412,7 @@ impl Context {
             &page,
             sidebar,
             |buf: &mut Buffer| all.print(buf),
-            &self.shared.themes,
+            &self.shared.style_files,
         );
         self.shared.fs.write(&final_file, v.as_bytes())?;
 
@@ -1385,9 +1421,9 @@ impl Context {
         page.description = "Settings of Rustdoc";
         page.root_path = "./";
 
-        let mut themes = self.shared.themes.clone();
+        let mut style_files = self.shared.style_files.clone();
         let sidebar = "<p class='location'>Settings</p><div class='sidebar-elems'></div>";
-        themes.push(PathBuf::from("settings.css"));
+        style_files.push(StylePath { path: PathBuf::from("settings.css"), disabled: false });
         let v = layout::render(
             &self.shared.layout,
             &page,
@@ -1396,7 +1432,7 @@ impl Context {
                 self.shared.static_root_path.as_deref().unwrap_or("./"),
                 &self.shared.resource_suffix,
             ),
-            &themes,
+            &style_files,
         );
         self.shared.fs.write(&settings_file, v.as_bytes())?;
 
@@ -1458,7 +1494,7 @@ impl Context {
                 &page,
                 |buf: &mut _| print_sidebar(self, it, buf),
                 |buf: &mut _| print_item(self, it, buf),
-                &self.shared.themes,
+                &self.shared.style_files,
             )
         } else {
             let mut url = self.root_path();

src/librustdoc/html/sources.rs

@@ -123,7 +123,7 @@ impl<'a> SourceCollector<'a> {
             &page,
             "",
             |buf: &mut _| print_src(buf, &contents),
-            &self.scx.themes,
+            &self.scx.style_files,
         );
         self.scx.fs.write(&cur, v.as_bytes())?;
         self.scx.local_sources.insert(p, href);