Add page-break option

Author: Evian-Zhang

guide/src/format/config.md

@@ -224,6 +224,7 @@ Available configuration options for the `[output.html.print]` table:
 
 - **enable:** Enable print support. When `false`, all print support will not be
   rendered. Defaults to `true`.
+- **page-break** Insert page breaks between chapters. Defaults to `true`.
 
 Available configuration options for the `[output.html.fold]` table:
 
@@ -292,6 +293,7 @@ input-404 = "not-found.md"
 
 [output.html.print]
 enable = true
+page-break = true
 
 [output.html.fold]
 enable = false

src/config.rs

@@ -580,11 +580,16 @@ impl HtmlConfig {
 pub struct Print {
     /// Whether print support is enabled.
     pub enable: bool,
+    /// Insert page breaks between chapters. Default: `true`.
+    pub page_break: bool,
 }
 
 impl Default for Print {
     fn default() -> Self {
-        Self { enable: true }
+        Self {
+            enable: true,
+            page_break: true,
+        }
     }
 }
 

src/renderer/html_handlebars/hbs_renderer.rs

@@ -45,6 +45,12 @@ impl HtmlHandlebars {
             ctx.html_config.curly_quotes,
             Some(&path),
         );
+        if !ctx.is_index && ctx.html_config.print.page_break {
+            // Add page break between chapters
+            // See https://developer.mozilla.org/en-US/docs/Web/CSS/break-before and https://developer.mozilla.org/en-US/docs/Web/CSS/page-break-before
+            // Add both two CSS properties because of the compatibility issue
+            print_content.push_str(r#"<div id="chapter_begin" style="break-before: page; page-break-before: always;"></div>"#);
+        }
         print_content.push_str(&fixed_content);
 
         // Update the context with data for this file