Add syntax highlighting with syntect.

src/filesystem.rs

@@ -41,9 +41,12 @@ pub mod qobject {
 
 use cxx_qt_lib::{QModelIndex, QString};
 use dirs;
+use log::warn;
 use std::fs;
 use std::fs::FileType;
-use log::warn;
+use syntect::highlighting::{Style, ThemeSet};
+use syntect::parsing::SyntaxSet;
+use syntect::html::highlighted_html_for_file;
 
 // TODO: Impleent a provider for QFileSystemModel::setIconProvider for icons.
 pub struct FileSystemImpl {
@@ -66,16 +69,19 @@ impl qobject::FileSystem {
         if path.is_empty() {
             return QString::default();
         }
-        // TODO: Use syntect for syntax highlighting?
-        //    https://github.com/trishume/syntect/blob/master/examples/syncat.rs
         if fs::metadata(path.to_string())
             .expect(format!("Failed to get file metadata {}", path).as_str())
             .is_file()
         {
-            QString::from(
-                fs::read_to_string(path.to_string())
-                    .expect(format!("Failed to read file {}", path).as_str()),
-            )
+            let ps = SyntaxSet::load_defaults_nonewlines();
+            let ts = ThemeSet::load_defaults();
+
+            if let Ok(result) = highlighted_html_for_file(std::path::Path::new(&path.to_string()), &ps, &ts.themes["base16-ocean.dark"]) {
+                QString::from(result)
+            } else {
+                warn!("Failed to read file {}", path);
+                QString::default()
+            }
         } else {
             warn!("Attempted to open file {} that is not a valid file", path);
             QString::default()