mdbook_selfpath/
lib.rs

1use mdbook::BookItem;
2use mdbook::book::Book;
3use mdbook::errors::Error;
4use mdbook::preprocess::{Preprocessor, PreprocessorContext};
5use regex::Regex;
6use std::path::Path;
7use std::path::PathBuf;
8
9#[derive(Default)]
10pub struct SelfPathPreprocessor;
11
12impl SelfPathPreprocessor {
13    pub fn new() -> SelfPathPreprocessor {
14        SelfPathPreprocessor
15    }
16}
17
18impl Preprocessor for SelfPathPreprocessor {
19    fn name(&self) -> &str {
20        "selfpath"
21    }
22
23    fn run(&self, ctx: &PreprocessorContext, mut book: Book) -> Result<Book, Error> {
24        // Determine the include-file-ext setting from [preprocessor.selfpath] (default true)
25        let include_ext = ctx
26            .config
27            .get_preprocessor(self.name())
28            .and_then(|table| table.get("include-file-ext"))
29            .and_then(|val| val.as_bool())
30            .unwrap_or(true);
31
32        // Determine the source directory name (relative to book root) from config or default "src"
33        let src_dir_name = &ctx.config.book.src;
34
35        // Regex to match {{#selfpath}}, {{ #selfpath }}, etc.
36        let selfpath_re = Regex::new(r"\{\{\s*selfpath\s*\}\}").unwrap();
37        let selftitle_re = Regex::new(r"\{\{\s*selftitle\s*\}\}").unwrap();
38
39        // Iterate through all chapters in the book (including subchapters)
40        book.for_each_mut(|item: &mut BookItem| {
41            if let BookItem::Chapter(chapter) = item {
42                // Only process real chapters that have a source path
43                if let Some(ref source_path) = chapter.source_path {
44                    let mut rel_path = PathBuf::new();
45                    // push book src path only if it's not "."
46                    if src_dir_name.as_path() != Path::new(".") {
47                        rel_path.push(&src_dir_name)
48                    }
49                    rel_path.push(source_path);
50                    if !include_ext {
51                        // Remove the .md extension if present
52                        rel_path.set_extension("");
53                    }
54                    // Convert path to a forward-slash string (for consistency across OS)
55                    let rel_path_str = rel_path.to_string_lossy().replace('\\', "/");
56                    // Perform the replacement in the chapter content using regex
57                    chapter.content = selfpath_re.replace_all(&chapter.content, rel_path_str.as_str()).to_string();
58
59                    let filename = source_path.file_name().and_then(|s| s.to_str()).unwrap_or("noname");
60                    let without_ext = filename
61                        .strip_suffix(".md")
62                        .unwrap_or(filename);
63                    chapter.content = selftitle_re.replace_all(&chapter.content, without_ext).to_string();
64                }
65            }
66        });
67        Ok(book)
68    }
69
70    fn supports_renderer(&self, _renderer: &str) -> bool {
71        // This is not strictly used in our setup, since main.rs handles "supports".
72        // We claim support for all renderers.
73        true
74    }
75}
mdbook_selfpath/lib.rs

mdbook_selfpath/
lib.rs
