Escape nb spaces with html entities when html.escape_nb_spaces is true

src/lib/bookoptions.rs

@@ -52,7 +52,7 @@ html.highlight_code:bool:true       # Provides syntax highlighting for code bloc
 html.highlight.js:tpl               # Set another highlight.js version than the bundled one
 html.highlight.css:tpl              # Set another highlight.js CSS theme than the default one
 html.side_notes:bool:false          # Display footnotes as side notes in HTML/Epub (experimental)
-
+html.escape_nb_spaces:bool:true     # Replace unicode non breaking spaces with  HTML entities and CSS
 
 # Standalone HTML options
 html_single.one_chapter:bool:false  # Display only one chapter at a time (with a button to display all)

src/lib/escape.rs

@@ -24,28 +24,22 @@ const NB_CHAR_NARROW:char = '\u{202F}'; // narrow non breaking space
 const NB_CHAR_EM:char = '\u{2002}'; // demi em space
 
 
-/// Escape non breaking spaces for HTML, so they are visible.
-#[doc(hidden)]
+/// Escape non breaking spaces for HTML, so there is no problem for displaying them if the font or browser
+/// doesn't know what to do with them
 pub fn escape_nb_spaces<'a, S: Into<Cow<'a, str>>>(input: S) -> Cow<'a, str> {
     let input = input.into();
-    if input.contains(|c| match c {
+    if let Some(first) = input.chars().position(|c| match c {
         NB_CHAR | NB_CHAR_NARROW | NB_CHAR_EM => true,
         _ => false
     }) {
-        let mut output = String::with_capacity(input.len());
-        for c in input.chars() {
+        let mut chars = input.chars().collect::<Vec<_>>();
+        let rest = chars.split_off(first);
+        let mut output = chars.into_iter().collect::<String>();
+        for c in rest {
             match c {
-                NB_CHAR_NARROW
-                    | NB_CHAR_EM
-                    | NB_CHAR
-                    => output.push_str(&format!("<span style = \"background-color: {}\">{}</span>",
-                                                match c {
-                                                    NB_CHAR => "#ffff66",
-                                                    NB_CHAR_NARROW => "#9999ff",
-                                                    NB_CHAR_EM => "#ff9999",
-                                                    _ => unreachable!()
-                                                },
-                                                c)),
+                NB_CHAR_NARROW  => output.push_str(r#"<span class = "nnbsp">&thinsp;</span>"#),
+                NB_CHAR_EM => output.push_str(r#"<span class = "ensp">&ensp;</span>"#),
+                NB_CHAR => output.push_str(r#"<span class = "nbsp">&nbsp;</span>"#),
                 _ => output.push(c),
             }
         }

src/lib/html.rs

@@ -390,7 +390,8 @@ impl<'a> HtmlRenderer<'a> {
                 } else {
                     content
                 };
-                if this.as_ref().book.options.get_bool("proofread.nb_spaces").unwrap() {
+
+                if this.as_ref().book.options.get_bool("html.escape_nb_spaces").unwrap() {
                     content = escape_nb_spaces(content);
                 }
                 Ok(content.into_owned())

src/lib/html_dir.rs

@@ -279,8 +279,11 @@ impl<'a> HtmlDirRenderer<'a> {
         let template_css = try!(compile_str(try!(self.html.book.get_template("html.css")).as_ref(),
                                             &self.html.book.source,
                                             "could not compile template 'html.css"));
-        let data = try!(self.html.book.get_metadata(|s| Ok(s.to_owned())))
-            .build();
+        let mut data = try!(self.html.book.get_metadata(|s| Ok(s.to_owned())));
+        if self.html.book.options.get_bool("proofread.nb_spaces").unwrap() {
+            data = data.insert_bool("display_spaces", true);
+        }
+         let data = data.build();
         let mut res:Vec<u8> = vec!();
         template_css.render_data(&mut res, &data);
         let css = String::from_utf8_lossy(&res);

src/lib/html_single.rs

@@ -163,9 +163,12 @@ impl<'a> HtmlSingleRenderer<'a> {
         let template_css = try!(compile_str(try!(self.html.book.get_template("html.css")).as_ref(),
                                             &self.html.book.source,
                                             "could not compile template 'html.css'"));
-        let data = try!(self.html.book.get_metadata(|s| self.render_vec(&try!(Parser::new().parse_inline(s)))))
-            .insert_bool(self.html.book.options.get_str("lang").unwrap(), true)
-            .build();
+        let mut data = try!(self.html.book.get_metadata(|s| self.render_vec(&try!(Parser::new().parse_inline(s)))))
+            .insert_bool(self.html.book.options.get_str("lang").unwrap(), true);
+        if self.html.book.options.get_bool("proofread.nb_spaces").unwrap() {
+            data = data.insert_bool("display_spaces", true);
+        }
+        let data = data.build();
         let mut res:Vec<u8> = vec!();
         template_css.render_data(&mut res, &data);
         let css = String::from_utf8_lossy(&res);

templates/epub/stylesheet.css

@@ -174,4 +174,21 @@ p.first-para {
     text-indent: 0;
 }
 
-                           
+/* Use this for escape narrow space so it is non-breaking */
+.nnbsp {
+    white-space: nowrap;
+}
+
+{{#display_spaces}}
+.nnbsp {
+    background-color: #9999ff;
+}
+
+.ensp {
+    background-color: #ff9999;
+}
+
+.nbsp {
+    background-color: #ffff66;
+}
+{{/display_spaces}}