Improve code block rendering

- Add HTML escapes
- Make highlighter static

Cargo.lock

@@ -444,7 +444,7 @@ dependencies = [
 
 [[package]]
 name = "snekdown"
-version = "0.2.0"
+version = "0.2.1"
 dependencies = [
  "crossbeam-utils 0.7.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "htmlescape 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "snekdown"
-version = "0.2.0"
+version = "0.2.1"
 authors = ["trivernis <trivernis@protonmail.com>"]
 edition = "2018"
 license-file = "LICENSE"

src/format/html.rs

@@ -2,6 +2,7 @@ use crate::elements::*;
 use htmlescape::{encode_attribute, encode_minimal};
 use minify::html::minify;
 use rayon::prelude::*;
+use std::cell::RefCell;
 use syntect::highlighting::ThemeSet;
 use syntect::html::highlighted_html_for_string;
 use syntect::parsing::SyntaxSet;
@@ -183,31 +184,41 @@ impl ToHtml for Cell {
     }
 }
 
+thread_local! {static PS: RefCell<SyntaxSet> = RefCell::new(SyntaxSet::load_defaults_nonewlines());}
+thread_local! {static TS: RefCell<ThemeSet> = RefCell::new(ThemeSet::load_defaults());}
+
 impl ToHtml for CodeBlock {
     fn to_html(&self) -> String {
         if self.language.len() > 0 {
-            let ps = SyntaxSet::load_defaults_nonewlines();
+            PS.with(|ps_cell| {
-            let ts = ThemeSet::load_defaults();
+                let ps = ps_cell.borrow();
                 if let Some(syntax) = ps.find_syntax_by_token(self.language.as_str()) {
+                    TS.with(|ts_cell| {
+                        let ts = ts_cell.borrow();
                         format!(
                             "<div><code lang='{}'>{}</code></div>",
                             encode_attribute(self.language.clone().as_str()),
                             highlighted_html_for_string(
-                        self.code.as_str(),
+                                encode_minimal(self.code.as_str()).as_str(),
                                 &ps,
                                 syntax,
                                 &ts.themes["InspiredGitHub"]
                             )
                         )
+                    })
                 } else {
                     format!(
                         "<div><code lang='{}'><pre>{}</pre></code></div>",
                         encode_attribute(self.language.clone().as_str()),
-                    self.code.clone()
+                        encode_minimal(self.code.as_str())
                     )
                 }
+            })
         } else {
-            format!("<div><code><pre>{}</pre></code></div>", self.code.clone())
+            format!(
+                "<div><code><pre>{}</pre></code></div>",
+                encode_minimal(self.code.as_str())
+            )
         }
     }
 }