Code highlighting

src/cmd/serve.rs

@@ -33,7 +33,9 @@ pub fn serve(interface: &str, port: &str) -> Result<()> {
     let mut mount = Mount::new();
     mount.mount("/", Static::new(Path::new("public/")));
     mount.mount("/livereload.js", livereload_handler);
-    let server = Iron::new(mount).http(address.clone()).unwrap();
+    // Starts with a _ to not trigger the unused lint
+    // we need to assign to a variable otherwise it will block
+    let _iron = Iron::new(mount).http(address.clone()).unwrap();
     println!("Web server is available at http://{}", address);
     println!("Press CTRL+C to stop");
 

src/config.rs

@@ -7,7 +7,7 @@ use toml::{Value as Toml, self};
 
 use errors::{Result, ResultExt};
 
-// TODO: disable tag(s)/category(ies) page generation
+
 #[derive(Debug, PartialEq, Serialize, Deserialize)]
 pub struct Config {
     /// Title of the site

src/main.rs

@@ -33,6 +33,7 @@ mod cmd;
 mod page;
 mod front_matter;
 mod site;
+mod markdown;
 
 
 fn main() {

src/markdown.rs

@@ -0,0 +1,150 @@
+use std::borrow::Cow::Owned;
+
+use pulldown_cmark as cmark;
+use self::cmark::{Parser, Event, Tag};
+
+use syntect::easy::HighlightLines;
+use syntect::parsing::SyntaxSet;
+use syntect::highlighting::ThemeSet;
+use syntect::html::{start_coloured_html_snippet, styles_to_coloured_html, IncludeBackground};
+
+
+// We need to put those in a struct to impl Send and sync
+struct Setup {
+    syntax_set: SyntaxSet,
+    theme_set: ThemeSet,
+}
+
+unsafe impl Send for Setup {}
+unsafe impl Sync for Setup {}
+
+lazy_static!{
+    static ref SETUP: Setup = Setup {
+        syntax_set: SyntaxSet::load_defaults_newlines(),
+        theme_set: ThemeSet::load_defaults()
+    };
+}
+
+
+struct CodeHighlightingParser<'a> {
+    // The block we're currently highlighting
+    highlighter: Option<HighlightLines<'a>>,
+    parser: Parser<'a>,
+}
+
+impl<'a> CodeHighlightingParser<'a> {
+    pub fn new(parser: Parser<'a>) -> CodeHighlightingParser<'a> {
+        CodeHighlightingParser {
+            highlighter: None,
+            parser: parser,
+        }
+    }
+}
+
+impl<'a> Iterator for CodeHighlightingParser<'a> {
+    type Item = Event<'a>;
+
+    fn next(&mut self) -> Option<Event<'a>> {
+        // Not using pattern matching to reduce indentation levels
+        let next_opt = self.parser.next();
+        if next_opt.is_none() {
+            return None;
+        }
+
+        let item = next_opt.unwrap();
+        // Below we just look for the start of a code block and highlight everything
+        // until we see the end of a code block.
+        // Everything else happens as normal in pulldown_cmark
+        match item {
+            Event::Text(text) => {
+                // if we are in the middle of a code block
+                if let Some(ref mut highlighter) = self.highlighter {
+                    let highlighted = &highlighter.highlight(&text);
+                    let html = styles_to_coloured_html(highlighted, IncludeBackground::Yes);
+                    Some(Event::Html(Owned(html)))
+                } else {
+                    Some(Event::Text(text))
+                }
+            },
+            Event::Start(Tag::CodeBlock(ref info)) => {
+                let syntax = info
+                    .split(' ')
+                    .next()
+                    .and_then(|lang| SETUP.syntax_set.find_syntax_by_token(lang))
+                    .unwrap_or_else(|| SETUP.syntax_set.find_syntax_plain_text());
+                self.highlighter = Some(
+                    HighlightLines::new(&syntax, &SETUP.theme_set.themes["base16-ocean.dark"])
+                );
+                let snippet = start_coloured_html_snippet(&SETUP.theme_set.themes["base16-ocean.dark"]);
+                Some(Event::Html(Owned(snippet)))
+            },
+            Event::End(Tag::CodeBlock(_)) => {
+                // reset highlight and close the code block
+                self.highlighter = None;
+                Some(Event::Html(Owned("</pre>".to_owned())))
+            },
+            _ => Some(item)
+        }
+
+    }
+}
+
+pub fn markdown_to_html(content: &str, highlight_code: bool) -> String {
+    let mut html = String::new();
+    if highlight_code {
+        let parser = CodeHighlightingParser::new(Parser::new(content));
+        cmark::html::push_html(&mut html, parser);
+    } else {
+        let parser = Parser::new(content);
+        cmark::html::push_html(&mut html, parser);
+    };
+    html
+}
+
+
+#[cfg(test)]
+mod tests {
+    use super::{markdown_to_html};
+
+    #[test]
+    fn test_markdown_to_html_simple() {
+        let res = markdown_to_html("# hello", true);
+        assert_eq!(res, "<h1>hello</h1>\n");
+    }
+
+    #[test]
+    fn test_markdown_to_html_code_block_highlighting_off() {
+        let res = markdown_to_html("```\n$ gutenberg server\n```", false);
+        assert_eq!(
+            res,
+            "<pre><code>$ gutenberg server\n</code></pre>\n"
+        );
+    }
+
+    #[test]
+    fn test_markdown_to_html_code_block_no_lang() {
+        let res = markdown_to_html("```\n$ gutenberg server\n$ ping\n```", true);
+        assert_eq!(
+            res,
+            "<pre style=\"background-color:#2b303b\">\n<span style=\"background-color:#2b303b;color:#c0c5ce;\">$ gutenberg server\n</span><span style=\"background-color:#2b303b;color:#c0c5ce;\">$ ping\n</span></pre>"
+        );
+    }
+
+    #[test]
+    fn test_markdown_to_html_code_block_with_lang() {
+        let res = markdown_to_html("```python\nlist.append(1)\n```", true);
+        assert_eq!(
+            res,
+            "<pre style=\"background-color:#2b303b\">\n<span style=\"background-color:#2b303b;color:#c0c5ce;\">list</span><span style=\"background-color:#2b303b;color:#c0c5ce;\">.</span><span style=\"background-color:#2b303b;color:#bf616a;\">append</span><span style=\"background-color:#2b303b;color:#c0c5ce;\">(</span><span style=\"background-color:#2b303b;color:#d08770;\">1</span><span style=\"background-color:#2b303b;color:#c0c5ce;\">)</span><span style=\"background-color:#2b303b;color:#c0c5ce;\">\n</span></pre>"
+        );
+    }
+    #[test]
+    fn test_markdown_to_html_code_block_with_unknown_lang() {
+        let res = markdown_to_html("```yolo\nlist.append(1)\n```", true);
+        // defaults to plain text
+        assert_eq!(
+            res,
+            "<pre style=\"background-color:#2b303b\">\n<span style=\"background-color:#2b303b;color:#c0c5ce;\">list.append(1)\n</span></pre>"
+        );
+    }
+}

src/page.rs

@@ -6,7 +6,6 @@ use std::path::Path;
 use std::result::Result as StdResult;
 
 
-use pulldown_cmark as cmark;
 use regex::Regex;
 use tera::{Tera, Context};
 use serde::ser::{SerializeStruct, self};
@@ -15,6 +14,7 @@ use slug::slugify;
 use errors::{Result, ResultExt};
 use config::Config;
 use front_matter::{FrontMatter};
+use markdown::markdown_to_html;
 
 
 lazy_static! {
@@ -22,13 +22,6 @@ lazy_static! {
     static ref SUMMARY_RE: Regex = Regex::new(r"<!-- more -->").unwrap();
 }
 
-fn markdown_to_html(content: &str) -> String {
-    let mut html = String::new();
-    let parser = cmark::Parser::new(content);
-    cmark::html::push_html(&mut html, parser);
-    html
-}
-
 
 #[derive(Clone, Debug, PartialEq, Deserialize)]
 pub struct Page {
@@ -120,13 +113,13 @@ impl Page {
         let mut page = Page::new(meta);
         page.filepath = filepath.to_string();
         page.raw_content = content.to_string();
-        page.content = markdown_to_html(&page.raw_content);
+        page.content = markdown_to_html(&page.raw_content, config.highlight_code.unwrap());
 
 
         if page.raw_content.contains("<!-- more -->") {
             page.summary = {
                 let summary = SUMMARY_RE.split(&page.raw_content).collect::<Vec<&str>>()[0];
-                markdown_to_html(summary)
+                markdown_to_html(summary, config.highlight_code.unwrap())
             }
         }