Add configuration option to disable the default hidelines feature for rust

Author: zgtm

Diff for: src/config.rs

@@ -697,13 +697,24 @@ impl Default for Playground {
 }
 
 /// Configuration for tweaking how the HTML renderer handles code blocks.
-#[derive(Debug, Default, Clone, PartialEq, Serialize, Deserialize)]
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
 #[serde(default, rename_all = "kebab-case")]
 pub struct Code {
+    /// Enable or disable the default line hiding with '#' for rust. Default: `true`.
+    pub default_hidelines: bool,
     /// A prefix string to hide lines per language (one or more chars).
     pub hidelines: HashMap<String, String>,
 }
 
+impl Default for Code {
+    fn default() -> Code {
+        Code {
+            default_hidelines: true,
+            hidelines: HashMap::<String, String>::default(),
+        }
+    }
+}
+
 /// Configuration of the search functionality of the HTML renderer.
 #[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
 #[serde(default, rename_all = "kebab-case")]

Diff for: src/renderer/html_handlebars/hbs_renderer.rs

@@ -956,7 +956,7 @@ fn hide_lines(html: &str, code_config: &Code) -> String {
             let classes = &caps[2];
             let code = &caps[3];
 
-            if classes.contains("language-rust") {
+            if classes.contains("language-rust") && code_config.default_hidelines {
                 format!(
                     "<code class=\"{}\">{}</code>",
                     classes,
@@ -1283,6 +1283,38 @@ mod tests {
                         map.insert("python".to_string(), "~".to_string());
                         map
                     },
+                    default_hidelines: true,
+                },
+            );
+            assert_eq!(&*got, *should_be);
+        }
+    }
+
+    #[test]
+    fn no_default_hide_lines() {
+        let inputs = [
+          (
+           "<pre class=\"playground\"><code class=\"language-rust\">\n# #![allow(unused)]\n#fn main() {\nx()\n#}</code></pre>",
+           "<pre class=\"playground\"><code class=\"language-rust\">\n# #![allow(unused)]\n#fn main() {\nx()\n#}</code></pre>",),
+          (
+           "<pre class=\"playground\"><code class=\"language-rust editable\">let s = \"foo\n # bar\n\";</code></pre>",
+           "<pre class=\"playground\"><code class=\"language-rust editable\">let s = \"foo\n # bar\n\";</code></pre>",),
+          (
+           "<pre class=\"playground\"><code class=\"language-rust editable\">let s = \"foo\n ## bar\n\";</code></pre>",
+           "<pre class=\"playground\"><code class=\"language-rust editable\">let s = \"foo\n ## bar\n\";</code></pre>",),
+          (
+           "<pre class=\"playground\"><code class=\"language-rust editable\">let s = \"foo\n # bar\n#\n\";</code></pre>",
+           "<pre class=\"playground\"><code class=\"language-rust editable\">let s = \"foo\n # bar\n#\n\";</code></pre>",),
+          (
+           "<code class=\"language-rust ignore\">let s = \"foo\n # bar\n\";</code>",
+           "<code class=\"language-rust ignore\">let s = \"foo\n # bar\n\";</code>",),
+        ];
+        for (src, should_be) in &inputs {
+            let got = hide_lines(
+                src,
+                &Code {
+                    hidelines: HashMap::<String, String>::default(),
+                    default_hidelines: false,
                 },
             );
             assert_eq!(&*got, *should_be);