Impl `rewrite_to_dir` config for navigations

src/renderer/html_handlebars/hbs_renderer.rs

@@ -219,12 +219,17 @@ impl HtmlHandlebars {
     }
 
     fn register_hbs_helpers(&self, handlebars: &mut Handlebars, html_config: &HtmlConfig) {
+        let HtmlConfig { no_section_label, ref rewrite_to_dir, .. } = *html_config;
         handlebars.register_helper("toc", Box::new(helpers::toc::RenderToc {
-            no_section_label: html_config.no_section_label,
-            rewrite_to_dir: html_config.rewrite_to_dir.to_owned(),
+            no_section_label,
+            rewrite_to_dir: rewrite_to_dir.to_owned(),
+        }));
+        handlebars.register_helper("previous", Box::new(helpers::navigation::Previous {
+            rewrite_to_dir: rewrite_to_dir.to_owned(),
+        }));
+        handlebars.register_helper("next", Box::new(helpers::navigation::Next {
+            rewrite_to_dir: rewrite_to_dir.to_owned(),
         }));
-        handlebars.register_helper("previous", Box::new(helpers::navigation::previous));
-        handlebars.register_helper("next", Box::new(helpers::navigation::next));
     }
 
     /// Copy across any additional CSS and JavaScript files which the book

src/renderer/html_handlebars/helpers/mod.rs

@@ -1,2 +1,38 @@
+use std::path::{Path, PathBuf};
+
 pub mod toc;
 pub mod navigation;
+
+/// Rewrite filename of path to directory index if matches any of filename
+/// pattern in `rewrite_names`.
+///
+/// * `path` - Path reference.
+/// * `rewrite_names` - Array of filename pattern to be rewritten.
+pub fn rewrite_to_dir_index<P: AsRef<Path>>(path: P, rewrite_names: &[String]) -> PathBuf {
+    let p = path.as_ref();
+    for name in rewrite_names.iter() {
+        if name.as_str() == p.file_name().unwrap_or_default() {
+            return p.with_file_name("");
+        }
+    }
+    return p.to_owned();
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn rewrite_to_dir_success() {
+        let names = vec!["index.html".to_owned(), "index.md".to_owned()];
+
+        let path = PathBuf::from("index.html");
+        assert_eq!(rewrite_to_dir_index(&path, &names), PathBuf::from(""));
+
+        let path = PathBuf::from("index.md");
+        assert_eq!(rewrite_to_dir_index(&path, &names), PathBuf::from(""));
+
+        let path = PathBuf::from("index.asp");
+        assert_eq!(rewrite_to_dir_index(&path, &names), path);
+    }
+}

src/renderer/html_handlebars/helpers/navigation.rs

@@ -2,7 +2,10 @@ use std::path::Path;
 use std::collections::BTreeMap;
 
 use serde_json;
-use handlebars::{Context, Handlebars, Helper, RenderContext, RenderError, Renderable};
+use handlebars::{Context, Handlebars, Helper, HelperDef, RenderContext, RenderError, Renderable};
+
+use super::rewrite_to_dir_index;
+
 
 type StringMap = BTreeMap<String, String>;
 
@@ -83,6 +86,7 @@ fn render(
     r: &Handlebars,
     rc: &mut RenderContext,
     chapter: &StringMap,
+    rewrite_names: &[String],
 ) -> Result<(), RenderError> {
     trace!("Creating BTreeMap to inject in context");
 
@@ -97,8 +101,7 @@ fn render(
         .get("path")
         .ok_or_else(|| RenderError::new("No path found for chapter in JSON data"))
         .and_then(|p| {
-            Path::new(p)
-                .with_extension("html")
+            rewrite_to_dir_index(Path::new(p).with_extension("html"), rewrite_names)
                 .to_str()
                 .ok_or_else(|| RenderError::new("Link could not be converted to str"))
                 .map(|p| context.insert("link".to_owned(), json!(p.replace("\\", "/"))))
@@ -116,24 +119,48 @@ fn render(
     Ok(())
 }
 
-pub fn previous(_h: &Helper, r: &Handlebars, rc: &mut RenderContext) -> Result<(), RenderError> {
+pub struct Previous {
+    pub rewrite_to_dir: Vec<String>,
+}
+
+impl Default for Previous {
+    fn default() -> Self {
+        Self { rewrite_to_dir: vec![] }
+    }
+}
+
+impl HelperDef for Previous {
+    fn call(&self, _h: &Helper, r: &Handlebars, rc: &mut RenderContext) -> Result<(), RenderError> {
         trace!("previous (handlebars helper)");
 
         if let Some(previous) = find_chapter(rc, Target::Previous)? {
-        render(_h, r, rc, &previous)?;
+            render(_h, r, rc, &previous, &self.rewrite_to_dir)?;
         }
 
         Ok(())
+    }
 }
 
-pub fn next(_h: &Helper, r: &Handlebars, rc: &mut RenderContext) -> Result<(), RenderError> {
+pub struct Next {
+    pub rewrite_to_dir: Vec<String>,
+}
+
+impl Default for Next {
+    fn default() -> Self {
+        Self { rewrite_to_dir: vec![] }
+    }
+}
+
+impl HelperDef for Next {
+    fn call(&self, _h: &Helper, r: &Handlebars, rc: &mut RenderContext) -> Result<(), RenderError> {
         trace!("next (handlebars helper)");
 
         if let Some(next) = find_chapter(rc, Target::Next)? {
-        render(_h, r, rc, &next)?;
+            render(_h, r, rc, &next, &self.rewrite_to_dir)?;
         }
 
         Ok(())
+    }
 }
 
 #[cfg(test)]
@@ -165,8 +192,8 @@ mod tests {
       });
 
         let mut h = Handlebars::new();
-        h.register_helper("previous", Box::new(previous));
-        h.register_helper("next", Box::new(next));
+        h.register_helper("previous", Box::new(Previous::default()));
+        h.register_helper("next", Box::new(Next::default()));
 
         assert_eq!(
             h.render_template(TEMPLATE, &data).unwrap(),
@@ -196,8 +223,8 @@ mod tests {
       });
 
         let mut h = Handlebars::new();
-        h.register_helper("previous", Box::new(previous));
-        h.register_helper("next", Box::new(next));
+        h.register_helper("previous", Box::new(Previous::default()));
+        h.register_helper("next", Box::new(Next::default()));
 
         assert_eq!(
             h.render_template(TEMPLATE, &data).unwrap(),
@@ -226,8 +253,8 @@ mod tests {
       });
 
         let mut h = Handlebars::new();
-        h.register_helper("previous", Box::new(previous));
-        h.register_helper("next", Box::new(next));
+        h.register_helper("previous", Box::new(Previous::default()));
+        h.register_helper("next", Box::new(Next::default()));
 
         assert_eq!(
             h.render_template(TEMPLATE, &data).unwrap(),

src/renderer/html_handlebars/helpers/toc.rs

@@ -1,10 +1,12 @@
-use std::path::{Path, PathBuf};
+use std::path::Path;
 use std::collections::BTreeMap;
 
 use serde_json;
 use handlebars::{Handlebars, Helper, HelperDef, RenderContext, RenderError};
 use pulldown_cmark::{html, Event, Parser, Tag};
 
+use super::rewrite_to_dir_index;
+
 // Handlebars helper to construct TOC
 pub struct RenderToc {
     pub no_section_label: bool,
@@ -72,7 +74,7 @@ impl HelperDef for RenderToc {
                     let tmp = {
                         // To be recognized by browsers, rewrite extenstion to `.html`.
                         let path = Path::new(path).with_extension("html");
-                        self.rewrite_directory_index(&path)
+                        rewrite_to_dir_index(&path, &self.rewrite_to_dir)
                     }
                         .to_str()
                         .unwrap()
@@ -140,41 +142,4 @@ impl HelperDef for RenderToc {
         rc.writer.write_all(b"</ol>")?;
         Ok(())
     }
-
-}
-
-impl RenderToc {
-    // Rewrite filenames matches any in `rewrite_to_dir` to directory index.
-    fn rewrite_directory_index(&self, path: &Path) -> PathBuf {
-        for filename in self.rewrite_to_dir.iter() {
-            if filename.as_str() == path.file_name().unwrap_or_default() {
-                return path.with_file_name("");
-            }
-        }
-        return path.to_owned();
-    }
-}
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-
-    #[test]
-    fn rewrite_dir_success() {
-        let render = RenderToc {
-            no_section_label: true,
-            rewrite_to_dir: vec![
-                "index.html".to_owned(),
-                "index.md".to_owned(),
-            ],
-        };
-        let path = PathBuf::from("index.html");
-        assert_eq!(render.rewrite_directory_index(&path), PathBuf::from(""));
-
-        let path = PathBuf::from("index.md");
-        assert_eq!(render.rewrite_directory_index(&path), PathBuf::from(""));
-
-        let path = PathBuf::from("index.asp");
-        assert_eq!(render.rewrite_directory_index(&path), path);
-    }
 }