[Draft] Feature/links preprocessor

examples/nop-preprocessor.rs

@@ -73,6 +73,7 @@ mod nop_lib {
     use super::*;
 
     /// A no-op preprocessor.
+    #[derive(Clone)]
     pub struct Nop;
 
     impl Nop {

examples/remove-emphasis/mdbook-remove-emphasis/src/main.rs

@@ -28,6 +28,7 @@ fn main() {
     }
 }
 
+#[derive(Clone)]
 struct RemoveEmphasis;
 
 impl Preprocessor for RemoveEmphasis {

guide/src/format/configuration/general.md

@@ -72,7 +72,7 @@ edition = "2015"   # the default edition for code blocks
 ```
 
 - **edition**: Rust edition to use by default for the code snippets. Default
-  is `"2015"`. Individual code blocks can be controlled with the `edition2015`,
+  is `"2015"`. Individual code blocks can be controlled with the `edition2015`, 
   `edition2018` or `edition2021` annotations, such as:
 
   ~~~text

guide/src/format/configuration/preprocessors.md

@@ -28,6 +28,7 @@ For information on how to create a new preprocessor, see the [Preprocessors for
 Preprocessors can be added by including a `preprocessor` table in `book.toml` with the name of the preprocessor.
 For example, if you have a preprocessor called `mdbook-example`, then you can include it with:
 
+**book.toml**
 ```toml
 [preprocessor.example]
 ```

guide/src/format/configuration/renderers.md

@@ -144,6 +144,10 @@ The following configuration options are available:
 - **no-section-label:** mdBook by defaults adds numeric section labels in the table of
   contents column. For example, "1.", "2.1". Set this option to true to disable
   those labels. Defaults to `false`.
+- **fold:** A subtable for configuring sidebar section-folding behavior.
+- **playground:** A subtable for configuring various playground settings.
+- **search:** A subtable for configuring the in-browser search functionality.
+  mdBook must be compiled with the `search` feature enabled (on by default).
 - **git-repository-url:**  A url to the git repository for the book. If provided
   an icon link will be output in the menu bar of the book.
 - **git-repository-icon:** The FontAwesome icon class to use for the git
@@ -157,6 +161,12 @@ The following configuration options are available:
   `https://bitbucket.org/<owner>/<repo>/src/<branch>/{path}?mode=edit`
   where {path} will be replaced with the full path of the file in the
   repository.
+- **redirect:** A subtable used for generating redirects when a page is moved.
+  The table contains key-value pairs where the key is where the redirect file
+  needs to be created, as an absolute path from the build directory, (e.g.
+  `/appendices/bibliography.html`). The value can be any valid URI the
+  browser should navigate to (e.g. `https://rust-lang.org/`,
+  `/overview.html`, or `../bibliography.html`).
 - **input-404:** The name of the markdown file used for missing files.
   The corresponding output file will be the same, with the extension replaced with `html`.
   Defaults to `404.md`.
@@ -287,6 +297,53 @@ The `[output.html.redirect]` table provides a way to add redirects.
 This is useful when you move, rename, or remove a page to ensure that links to the old URL will go to the new location.
 
 ```toml
+[book]
+title = "Example book"
+authors = ["John Doe", "Jane Doe"]
+description = "The example book covers examples."
+
+[output.html]
+theme = "my-theme"
+default-theme = "light"
+preferred-dark-theme = "navy"
+curly-quotes = true
+mathjax-support = false
+copy-fonts = true
+google-analytics = "UA-123456-7"
+additional-css = ["custom.css", "custom2.css"]
+additional-js = ["custom.js"]
+no-section-label = false
+git-repository-url = "https://github.com/rust-lang/mdBook"
+git-repository-icon = "fa-github"
+edit-url-template = "https://github.com/rust-lang/mdBook/edit/master/guide/{path}"
+site-url = "/example-book/"
+cname = "myproject.rs"
+input-404 = "not-found.md"
+
+[output.html.print]
+enable = true
+
+[output.html.fold]
+enable = false
+level = 0
+
+[output.html.playground]
+editable = false
+copy-js = true
+line-numbers = false
+
+[output.html.search]
+enable = true
+limit-results = 30
+teaser-word-count = 30
+use-boolean-and = true
+boost-title = 2
+boost-hierarchy = 1
+boost-paragraph = 1
+expand = true
+heading-split-level = 3
+copy-js = true
+
 [output.html.redirect]
 "/appendices/bibliography.html" = "https://rustc-dev-guide.rust-lang.org/appendix/bibliography.html"
 "/other-installation-methods.html" = "../infra/other-installation-methods.html"
@@ -317,3 +374,20 @@ only whether it is enabled or disabled.
 
 See [the preprocessors documentation](preprocessors.md) for how to
 specify which preprocessors should run before the Markdown renderer.
+
+### Custom Renderers
+
+A custom renderer can be enabled by adding a `[output.foo]` table to your
+`book.toml`. Similar to [preprocessors](preprocessors.md) this will
+instruct `mdbook` to pass a representation of the book to `mdbook-foo` for
+rendering. See the [alternative backends] chapter for more detail.
+
+The custom renderer has access to all the fields within its table (i.e.
+anything under `[output.foo]`). mdBook checks for two common fields:
+
+- **command:** The command to execute for this custom renderer. Defaults to
+  the name of the renderer with the `mdbook-` prefix (such as `mdbook-foo`).
+- **optional:** If `true`, then the command will be ignored if it is not
+  installed, otherwise mdBook will fail with an error. Defaults to `false`.
+
+[alternative backends]: ../../for_developers/backends.md

src/book/mod.rs

@@ -426,6 +426,11 @@ impl MDBook {
             .unwrap_or_default()
             .theme_dir(&self.root)
     }
+
+    /// Clone registered boxed preprocessors Vec
+    pub fn clone_preprocessors(&self) -> Vec<Box<dyn Preprocessor>> {
+        self.preprocessors.clone()
+    }
 }
 
 /// Look at the `Config` and try to figure out what renderers to use.
@@ -865,6 +870,7 @@ mod tests {
         assert!(should_run);
     }
 
+    #[derive(Default, Clone)]
     struct BoolPreprocessor(bool);
     impl Preprocessor for BoolPreprocessor {
         fn name(&self) -> &str {

src/cmd/test.rs

@@ -1,7 +1,7 @@
 use super::command_prelude::*;
 use crate::get_book_dir;
 use clap::builder::NonEmptyStringValueParser;
-use clap::ArgAction;
+use clap::{Arg, ArgAction, ArgMatches, Command};
 use mdbook::errors::Result;
 use mdbook::MDBook;
 use std::path::PathBuf;

src/config.rs

@@ -414,6 +414,8 @@ pub struct BookConfig {
     /// The direction of text in the book: Left-to-right (LTR) or Right-to-left (RTL).
     /// When not specified, the text direction is derived from [`BookConfig::language`].
     pub text_direction: Option<TextDirection>,
+    /// The book version.
+    pub version: Option<String>,
 }
 
 impl Default for BookConfig {
@@ -426,6 +428,7 @@ impl Default for BookConfig {
             multilingual: false,
             language: Some(String::from("en")),
             text_direction: None,
+            version: Some(String::from("0.0.1")),
         }
     }
 }
@@ -792,6 +795,7 @@ mod tests {
         multilingual = true
         src = "source"
         language = "ja"
+        version = "0.0.1"
 
         [build]
         build-dir = "outputs"
@@ -832,6 +836,7 @@ mod tests {
             src: PathBuf::from("source"),
             language: Some(String::from("ja")),
             text_direction: None,
+            version: Some(String::from("0.0.1")),
         };
         let build_should_be = BuildConfig {
             build_dir: PathBuf::from("outputs"),

src/preprocess/index.rs

@@ -9,7 +9,7 @@ use once_cell::sync::Lazy;
 
 /// A preprocessor for converting file name `README.md` to `index.md` since
 /// `README.md` is the de facto index file in markdown-based documentation.
-#[derive(Default)]
+#[derive(Default, Clone)]
 pub struct IndexPreprocessor;
 
 impl IndexPreprocessor {