Move Playground and comma/space class normalization into a pulldown-cmark filter

This avoids scanning over all the HTML with a regex, so it should be faster.

src/renderer/html_handlebars/hbs_renderer.rs

@@ -62,6 +62,8 @@ impl HtmlHandlebars {
             &content,
             ctx.html_config.curly_quotes,
             self.syntaxes.borrow().as_ref().unwrap(),
+            &ctx.html_config.playground,
+            ctx.edition,
         );
 
         let fixed_content = utils::render_markdown_with_path(
@@ -69,6 +71,8 @@ impl HtmlHandlebars {
             ctx.html_config.curly_quotes,
             Some(&path),
             self.syntaxes.borrow().as_ref().unwrap(),
+            &ctx.html_config.playground,
+            ctx.edition,
         );
         if !ctx.is_index && ctx.html_config.print.page_break  {
             // Add page break between chapters
@@ -121,7 +125,7 @@ impl HtmlHandlebars {
         debug!("Render template");
         let rendered = ctx.handlebars.render("index", &ctx.data)?;
 
-        let rendered = self.post_process(rendered, &ctx.html_config.playground, ctx.edition);
+        let rendered = self.post_process(rendered);
 
         // Write to file
         debug!("Creating {}", filepath.display());
@@ -132,8 +136,7 @@ impl HtmlHandlebars {
             ctx.data.insert("path_to_root".to_owned(), json!(""));
             ctx.data.insert("is_index".to_owned(), json!(true));
             let rendered_index = ctx.handlebars.render("index", &ctx.data)?;
-            let rendered_index =
+            let rendered_index = self.post_process(rendered_index);
-                self.post_process(rendered_index, &ctx.html_config.playground, ctx.edition);
             debug!("Creating index.html from {}", ctx_path);
             utils::fs::write_file(&ctx.destination, "index.html", rendered_index.as_bytes())?;
         }
@@ -171,6 +174,8 @@ impl HtmlHandlebars {
             &content_404,
             html_config.curly_quotes,
             self.syntaxes.borrow().as_ref().unwrap(),
+            &html_config.playground,
+            ctx.config.rust.edition,
         );
 
         let mut data_404 = data.clone();
@@ -197,8 +202,7 @@ impl HtmlHandlebars {
         data_404.insert("title".to_owned(), json!(title));
         let rendered = handlebars.render("index", &data_404)?;
 
-        let rendered =
+        let rendered = self.post_process(rendered);
-            self.post_process(rendered, &html_config.playground, ctx.config.rust.edition);
         let output_file = get_404_output_file(&html_config.input_404);
         utils::fs::write_file(destination, output_file, rendered.as_bytes())?;
         debug!("Creating 404.html ✓");
@@ -206,15 +210,8 @@ impl HtmlHandlebars {
     }
 
     #[cfg_attr(feature = "cargo-clippy", allow(clippy::let_and_return))]
-    fn post_process(
+    fn post_process(&self, rendered: String) -> String {
-        &self,
-        rendered: String,
-        playground_config: &Playground,
-        edition: Option<RustEdition>,
-    ) -> String {
         let rendered = build_header_links(&rendered);
-        let rendered = fix_code_blocks(&rendered);
-        let rendered = add_playground_pre(&rendered, playground_config, edition);
 
         rendered
     }
@@ -595,8 +592,7 @@ impl Renderer for HtmlHandlebars {
             debug!("Render template");
             let rendered = handlebars.render("index", &data)?;
 
-            let rendered =
+            let rendered = self.post_process(rendered);
-                self.post_process(rendered, &html_config.playground, ctx.config.rust.edition);
 
             utils::fs::write_file(destination, "print.html", rendered.as_bytes())?;
             debug!("Creating print.html ✓");
@@ -1000,6 +996,10 @@ fn partition_source(s: &str) -> (String, String) {
     (before, after)
 }
 
+lazy_static! {
+    static ref BORING_LINES_REGEX: Regex = Regex::new(r"^(\s*)#(.?)(.*)$").unwrap();
+}
+
 struct RenderItemContext<'a> {
     handlebars: &'a Handlebars<'a>,
     destination: PathBuf,

src/utils/highlight.rs

@@ -86,10 +86,8 @@ impl<'a> HtmlGenerator<'a> {
         if did_boringify {
             // Since the boring scope is preceded only by a Pop operation,
             // it must be the first match on the line for <span class="">
-            formatted_line = formatted_line.replace(
+            formatted_line =
-                r#"<span class="">"#,
+                formatted_line.replace(r#"<span class="">"#, r#"<span class="boring">"#);
-                r#"<span class="boring">"#,
-                );
         }
         self.open_spans += delta;
         self.html.push_str(&formatted_line);

src/utils/mod.rs

@@ -7,6 +7,7 @@ pub(crate) mod toml_ext;
 use crate::errors::Error;
 use regex::Regex;
 
+use crate::config::{Playground, RustEdition};
 use pulldown_cmark::{html, CodeBlockKind, CowStr, Event, Options, Parser, Tag};
 use syntect::html::ClassStyle;
 use syntect::parsing::SyntaxReference;
@@ -184,8 +185,21 @@ fn adjust_links<'a>(event: Event<'a>, path: Option<&Path>) -> Event<'a> {
 }
 
 /// Wrapper around the pulldown-cmark parser for rendering markdown to HTML.
-pub fn render_markdown(text: &str, curly_quotes: bool, syntaxes: &SyntaxSet) -> String {
+pub fn render_markdown(
-    render_markdown_with_path(text, curly_quotes, None, syntaxes)
+    text: &str,
+    curly_quotes: bool,
+    syntaxes: &SyntaxSet,
+    playground_config: &Playground,
+    default_edition: Option<RustEdition>,
+) -> String {
+    render_markdown_with_path(
+        text,
+        curly_quotes,
+        None,
+        syntaxes,
+        playground_config,
+        default_edition,
+    )
 }
 
 pub fn new_cmark_parser(text: &str, curly_quotes: bool) -> Parser<'_, '_> {
@@ -205,18 +219,20 @@ pub fn render_markdown_with_path(
     curly_quotes: bool,
     path: Option<&Path>,
     syntaxes: &SyntaxSet,
+    playground_config: &Playground,
+    default_edition: Option<RustEdition>,
 ) -> String {
     let mut s = String::with_capacity(text.len() * 3 / 2);
     let p = new_cmark_parser(text, curly_quotes);
-    let mut highlighter = SyntaxHighlighter::default();
+    let mut highlighter = SyntaxHighlighter::new(playground_config, default_edition);
     let events = p
         .map(clean_codeblock_headers)
-        .map(|event| highlighter.highlight(syntaxes, event))
         .map(|event| adjust_links(event, path))
         .flat_map(|event| {
             let (a, b) = wrap_tables(event);
             a.into_iter().chain(b)
-        });
+        })
+        .map(|event| highlighter.highlight(syntaxes, event));
 
     html::push_html(&mut s, events);
     s
@@ -234,20 +250,40 @@ fn wrap_tables(event: Event<'_>) -> (Option<Event<'_>>, Option<Event<'_>>) {
     }
 }
 
-#[derive(Default)]
 struct SyntaxHighlighter<'a> {
     highlight: bool,
     is_rust: bool,
+    is_playground: bool,
+    is_editable: bool,
     syntax: Option<&'a SyntaxReference>,
+    playground_config: &'a Playground,
+    default_edition: Option<RustEdition>,
 }
 
 impl<'a> SyntaxHighlighter<'a> {
+    fn new(playground_config: &'a Playground, default_edition: Option<RustEdition>) -> Self {
+        SyntaxHighlighter {
+            highlight: false,
+            is_rust: false,
+            is_playground: false,
+            is_editable: false,
+            syntax: None,
+            playground_config,
+            default_edition,
+        }
+    }
+
     fn highlight<'b>(&mut self, syntaxes: &'a SyntaxSet, event: Event<'b>) -> Event<'b> {
         match event {
             Event::Start(Tag::CodeBlock(CodeBlockKind::Fenced(ref info))) => {
                 self.highlight = true;
-                let lang_name = info.split(',').next();
+                let mut classes: Vec<_> = info
-                if let Some(name) = lang_name {
+                    .replace(",", " ")
+                    .split(' ')
+                    .map(String::from)
+                    .filter(|x| !x.is_empty())
+                    .collect();
+                if let Some(name) = classes.first() {
                     // If we're given an empty name, or it is marked as
                     // plaintext, we shouldn't highlight it.
                     if name.is_empty()
@@ -270,19 +306,64 @@ impl<'a> SyntaxHighlighter<'a> {
                             self.is_rust = true;
                         }
                     }
-                    event
+                    if self.is_rust {
+                        let ignore = classes.iter().find(|&x| x == "ignore").is_some();
+                        let noplayground = classes.iter().find(|&x| x == "noplayground").is_some();
+                        let noplaypen = classes.iter().find(|&x| x == "noplaypen").is_some();
+                        let mdbook_runnable =
+                            classes.iter().find(|&x| x == "mdbook-runnable").is_some();
+                        // Enable playground
+                        if (!ignore && !noplayground && !noplaypen) || mdbook_runnable {
+                            self.is_editable = classes.iter().find(|&x| x == "editable").is_some();
+                            let contains_e2015 =
+                                classes.iter().find(|&x| x == "edition2015").is_some();
+                            let contains_e2018 =
+                                classes.iter().find(|&x| x == "edition2018").is_some();
+                            let contains_e2021 =
+                                classes.iter().find(|&x| x == "edition2021").is_some();
+                            // if the user forced edition, we should not overwrite it
+                            if !contains_e2015 && !contains_e2018 && !contains_e2021 {
+                                match self.default_edition {
+                                    Some(RustEdition::E2015) => {
+                                        classes.push("edition2015".to_owned())
+                                    }
+                                    Some(RustEdition::E2018) => {
+                                        classes.push("edition2018".to_owned())
+                                    }
+                                    Some(RustEdition::E2021) => {
+                                        classes.push("edition2021".to_owned())
+                                    }
+                                    None => {}
+                                }
+                            }
+                            self.is_playground = true;
+                            return Event::Html(CowStr::from(format!(
+                                r#"<pre class="playground"><code class="language-{}">"#,
+                                classes.join(" ")
+                            )));
+                        }
+                    }
                 } else {
                     // We also don't perform auto-detection of languages, so we
                     // shouldn't highlight code blocks without lang tags.
                     self.highlight = false;
-                    event
+                }
+                if classes.is_empty() {
+                    Event::Html(CowStr::from("<pre><code>"))
+                } else {
+                    Event::Html(CowStr::from(format!(
+                        r#"<pre><code class="language-{}">"#,
+                        classes.join(" ")
+                    )))
                 }
             }
             Event::End(Tag::CodeBlock(CodeBlockKind::Fenced(_))) => {
                 self.highlight = false;
                 self.is_rust = false;
                 self.syntax = None;
-                event
+                self.is_playground = false;
+                self.is_editable = false;
+                Event::Html(CowStr::from("</code></pre>"))
             }
             Event::Text(ref code) if self.highlight => {
                 let mut gen = highlight::HtmlGenerator::new(
@@ -290,9 +371,19 @@ impl<'a> SyntaxHighlighter<'a> {
                     syntaxes,
                     ClassStyle::SpacedPrefixed { prefix: "syn-" },
                 );
+                let needs_wrapped = self.is_rust
+                    && !(self.playground_config.editable && self.is_editable)
+                    && !code.contains("fn main")
+                    && !code.contains("quick_main!");
+                if needs_wrapped {
+                    gen.parse_line("# fn main() {\n", self.is_rust);
+                }
                 for line in LinesWithEndings::from(code) {
                     gen.parse_line(line, self.is_rust);
                 }
+                if needs_wrapped {
+                    gen.parse_line("# }\n", self.is_rust);
+                }
                 Event::Html(CowStr::from(gen.finalize()))
             }
             _ => event,
@@ -300,41 +391,6 @@ impl<'a> SyntaxHighlighter<'a> {
     }
 }
 
-struct EventQuoteConverter {
-    enabled: bool,
-    convert_text: bool,
-}
-
-impl EventQuoteConverter {
-    fn new(enabled: bool) -> Self {
-        EventQuoteConverter {
-            enabled,
-            convert_text: true,
-        }
-    }
-
-    fn convert<'a>(&mut self, event: Event<'a>) -> Event<'a> {
-        if !self.enabled {
-            return event;
-        }
-
-        match event {
-            Event::Start(Tag::CodeBlock(_)) => {
-                self.convert_text = false;
-                event
-            }
-            Event::End(Tag::CodeBlock(_)) => {
-                self.convert_text = true;
-                event
-            }
-            Event::Text(ref text) if self.convert_text => {
-                Event::Text(CowStr::from(convert_quotes_to_curly(text)))
-            }
-            _ => event,
-        }
-    }
-}
-
 fn clean_codeblock_headers(event: Event<'_>) -> Event<'_> {
     match event {
         Event::Start(Tag::CodeBlock(CodeBlockKind::Fenced(ref info))) => {
@@ -389,6 +445,7 @@ mod tests {
         }
 
         use super::super::render_markdown;
+        use crate::config::{Playground, RustEdition};
 
         #[test]
         fn preserves_external_links() {
@@ -396,7 +453,9 @@ mod tests {
                 render_markdown(
                     "[example](https://www.rust-lang.org/)",
                     false,
-                    &default_syntaxes()
+                    &default_syntaxes(),
+                    &Playground::default(),
+                    None,
                 ),
                 "<p><a href=\"https://www.rust-lang.org/\">example</a></p>\n"
             );
@@ -405,14 +464,22 @@ mod tests {
         #[test]
         fn it_can_adjust_markdown_links() {
             assert_eq!(
-                render_markdown("[example](example.md)", false, &default_syntaxes()),
+                render_markdown(
+                    "[example](example.md)",
+                    false,
+                    &default_syntaxes(),
+                    &Playground::default(),
+                    None,
+                ),
                 "<p><a href=\"example.html\">example</a></p>\n"
             );
             assert_eq!(
                 render_markdown(
                     "[example_anchor](example.md#anchor)",
                     false,
-                    &default_syntaxes()
+                    &default_syntaxes(),
+                    &Playground::default(),
+                    None,
                 ),
                 "<p><a href=\"example.html#anchor\">example_anchor</a></p>\n"
             );
@@ -422,7 +489,9 @@ mod tests {
                 render_markdown(
                     "[phantom data](foo.html#phantomdata)",
                     false,
-                    &default_syntaxes()
+                    &default_syntaxes(),
+                    &Playground::default(),
+                    None,
                 ),
                 "<p><a href=\"foo.html#phantomdata\">phantom data</a></p>\n"
             );
@@ -441,13 +510,28 @@ mod tests {
 </tbody></table>
 </div>
 "#.trim();
-            assert_eq!(render_markdown(src, false), out);
+            assert_eq!(
+                render_markdown(
+                    src,
+                    false,
+                    &default_syntaxes(),
+                    &Playground::default(),
+                    None,
+                ),
+                out
+            );
         }
 
         #[test]
         fn it_can_keep_quotes_straight() {
             assert_eq!(
-                render_markdown("'one'", false, &default_syntaxes()),
+                render_markdown(
+                    "'one'",
+                    false,
+                    &default_syntaxes(),
+                    &Playground::default(),
+                    None,
+                ),
                 "<p>'one'</p>\n"
             );
         }
@@ -465,7 +549,16 @@ mod tests {
 </code></pre>
 <p><code>'three'</code> ‘four’</p>
 "#;
-            assert_eq!(render_markdown(input, true, &default_syntaxes()), expected);
+            assert_eq!(
+                render_markdown(
+                    input,
+                    true,
+                    &default_syntaxes(),
+                    &Playground::default(),
+                    None,
+                ),
+                expected
+            );
         }
 
         #[test]
@@ -481,7 +574,7 @@ more text with spaces
 "#;
 
             let expected = r#"<p>some text with spaces</p>
-<pre><code class="language-rust"><span class="syn-source syn-rust"><span class="syn-meta syn-function syn-rust"><span class="syn-meta syn-function syn-rust"><span class="syn-storage syn-type syn-function syn-rust">fn</span> </span><span class="syn-entity syn-name syn-function syn-rust">main</span></span><span class="syn-meta syn-function syn-rust"><span class="syn-meta syn-function syn-parameters syn-rust"><span class="syn-punctuation syn-section syn-parameters syn-begin syn-rust">(</span></span><span class="syn-meta syn-function syn-rust"><span class="syn-meta syn-function syn-parameters syn-rust"><span class="syn-punctuation syn-section syn-parameters syn-end syn-rust">)</span></span></span></span><span class="syn-meta syn-function syn-rust"> </span><span class="syn-meta syn-function syn-rust"><span class="syn-meta syn-block syn-rust"><span class="syn-punctuation syn-section syn-block syn-begin syn-rust">{</span>
+<pre class="playground"><code class="language-rust"><span class="syn-source syn-rust"><span class="syn-meta syn-function syn-rust"><span class="syn-meta syn-function syn-rust"><span class="syn-storage syn-type syn-function syn-rust">fn</span> </span><span class="syn-entity syn-name syn-function syn-rust">main</span></span><span class="syn-meta syn-function syn-rust"><span class="syn-meta syn-function syn-parameters syn-rust"><span class="syn-punctuation syn-section syn-parameters syn-begin syn-rust">(</span></span><span class="syn-meta syn-function syn-rust"><span class="syn-meta syn-function syn-parameters syn-rust"><span class="syn-punctuation syn-section syn-parameters syn-end syn-rust">)</span></span></span></span><span class="syn-meta syn-function syn-rust"> </span><span class="syn-meta syn-function syn-rust"><span class="syn-meta syn-block syn-rust"><span class="syn-punctuation syn-section syn-block syn-begin syn-rust">{</span>
 
 <span class="syn-comment syn-line syn-double-slash syn-rust"><span class="syn-punctuation syn-definition syn-comment syn-rust">//</span> code inside is unchanged
 </span>
@@ -490,8 +583,26 @@ more text with spaces
 </span></code></pre>
 <p>more text with spaces</p>
 "#;
-            assert_eq!(render_markdown(input, false, &default_syntaxes()), expected);
+            assert_eq!(
-            assert_eq!(render_markdown(input, true, &default_syntaxes()), expected);
+                render_markdown(
+                    input,
+                    false,
+                    &default_syntaxes(),
+                    &Playground::default(),
+                    None,
+                ),
+                expected
+            );
+            assert_eq!(
+                render_markdown(
+                    input,
+                    true,
+                    &default_syntaxes(),
+                    &Playground::default(),
+                    None,
+                ),
+                expected
+            );
         }
 
         #[test]
@@ -501,10 +612,27 @@ more text with spaces
 ```
 "#;
 
-            let expected = r#"<pre><code class="language-rust,no_run,should_panic,property_3"></code></pre>
+            let expected = r#"<pre class="playground"><code class="language-rust no_run should_panic property_3"></code></pre>"#;
-"#;
+            assert_eq!(
-            assert_eq!(render_markdown(input, false, &default_syntaxes()), expected);
+                render_markdown(
-            assert_eq!(render_markdown(input, true, &default_syntaxes()), expected);
+                    input,
+                    false,
+                    &default_syntaxes(),
+                    &Playground::default(),
+                    None,
+                ),
+                expected
+            );
+            assert_eq!(
+                render_markdown(
+                    input,
+                    true,
+                    &default_syntaxes(),
+                    &Playground::default(),
+                    None,
+                ),
+                expected
+            );
         }
 
         #[test]
@@ -514,10 +642,27 @@ more text with spaces
 ```
 "#;
 
-            let expected = r#"<pre><code class="language-rust,,,,,no_run,,,should_panic,,,,property_3"></code></pre>
+            let expected = r#"<pre class="playground"><code class="language-rust no_run should_panic property_3"></code></pre>"#;
-"#;
+            assert_eq!(
-            assert_eq!(render_markdown(input, false, &default_syntaxes()), expected);
+                render_markdown(
-            assert_eq!(render_markdown(input, true, &default_syntaxes()), expected);
+                    input,
+                    false,
+                    &default_syntaxes(),
+                    &Playground::default(),
+                    None,
+                ),
+                expected
+            );
+            assert_eq!(
+                render_markdown(
+                    input,
+                    true,
+                    &default_syntaxes(),
+                    &Playground::default(),
+                    None,
+                ),
+                expected
+            );
         }
 
         #[test]
@@ -527,19 +672,164 @@ more text with spaces
 ```
 "#;
 
-            let expected = r#"<pre><code class="language-rust"></code></pre>
+            let expected = r#"<pre class="playground"><code class="language-rust"></code></pre>"#;
-"#;
+            assert_eq!(
-            assert_eq!(render_markdown(input, false, &default_syntaxes()), expected);
+                render_markdown(
-            assert_eq!(render_markdown(input, true, &default_syntaxes()), expected);
+                    input,
+                    false,
+                    &default_syntaxes(),
+                    &Playground::default(),
+                    None,
+                ),
+                expected
+            );
+            assert_eq!(
+                render_markdown(
+                    input,
+                    true,
+                    &default_syntaxes(),
+                    &Playground::default(),
+                    None,
+                ),
+                expected
+            );
+        }
 
-            // FIXME: Why are we doing this twice? It seems to be the same
+        // These HTML strings get very, very long.
-            // input and assertions.
+        // What I do is copy them out of here,
-            let input = r#"
+        // paste them into a document.write() call in the JavaScript console,
-```rust
+        // and then I can read the HTML in the DOM inspector to see if it looks right.
-```
+        #[test]
-"#;
+        fn add_playground() {
-            assert_eq!(render_markdown(input, false, &default_syntaxes()), expected);
+            let inputs = [
-            assert_eq!(render_markdown(input, true, &default_syntaxes()), expected);
+              ("```rust\nx()\n```",
+               "<pre class=\"playground\"><code class=\"language-rust\"><span class=\"boring\"><span class=\"syn-source syn-rust\"><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-storage syn-type syn-function syn-rust\">fn</span> </span><span class=\"syn-entity syn-name syn-function syn-rust\">main</span></span><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-function syn-parameters syn-rust\"><span class=\"syn-punctuation syn-section syn-parameters syn-begin syn-rust\">(</span></span><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-function syn-parameters syn-rust\"><span class=\"syn-punctuation syn-section syn-parameters syn-end syn-rust\">)</span></span></span></span><span class=\"syn-meta syn-function syn-rust\"> </span><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-block syn-rust\"><span class=\"syn-punctuation syn-section syn-block syn-begin syn-rust\">{</span>\n</span></span></span></span><span class=\"syn-source syn-rust\"><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-block syn-rust\"><span class=\"syn-support syn-function syn-rust\">x</span><span class=\"syn-meta syn-group syn-rust\"><span class=\"syn-punctuation syn-section syn-group syn-begin syn-rust\">(</span></span><span class=\"syn-meta syn-group syn-rust\"><span class=\"syn-punctuation syn-section syn-group syn-end syn-rust\">)</span></span>\n\n</span></span></span><span class=\"boring\"><span class=\"syn-source syn-rust\"><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-block syn-rust\"><span class=\"syn-punctuation syn-section syn-block syn-end syn-rust\">}</span></span></span>\n</span></span><span class=\"syn-source syn-rust\"></span></code></pre>"),
+              ("```rust\nfn main() {}\n```",
+               "<pre class=\"playground\"><code class=\"language-rust\"><span class=\"syn-source syn-rust\"><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-storage syn-type syn-function syn-rust\">fn</span> </span><span class=\"syn-entity syn-name syn-function syn-rust\">main</span></span><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-function syn-parameters syn-rust\"><span class=\"syn-punctuation syn-section syn-parameters syn-begin syn-rust\">(</span></span><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-function syn-parameters syn-rust\"><span class=\"syn-punctuation syn-section syn-parameters syn-end syn-rust\">)</span></span></span></span><span class=\"syn-meta syn-function syn-rust\"> </span><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-block syn-rust\"><span class=\"syn-punctuation syn-section syn-block syn-begin syn-rust\">{</span></span><span class=\"syn-meta syn-block syn-rust\"><span class=\"syn-punctuation syn-section syn-block syn-end syn-rust\">}</span></span></span>\n\n</span></code></pre>"),
+              ("```rust editable\nlet s = \"foo\n # bar\n\";\n```",
+               "<pre class=\"playground\"><code class=\"language-rust editable\"><span class=\"syn-source syn-rust\"><span class=\"syn-storage syn-type syn-rust\">let</span> s <span class=\"syn-keyword syn-operator syn-assignment syn-rust\">=</span> <span class=\"syn-string syn-quoted syn-double syn-rust\"><span class=\"syn-punctuation syn-definition syn-string syn-begin syn-rust\">&quot;</span>foo\n\n</span></span><span class=\"boring\"><span class=\"syn-source syn-rust\"><span class=\"syn-string syn-quoted syn-double syn-rust\"> bar\n</span></span></span><span class=\"syn-source syn-rust\"><span class=\"syn-string syn-quoted syn-double syn-rust\"><span class=\"syn-punctuation syn-definition syn-string syn-end syn-rust\">&quot;</span></span><span class=\"syn-punctuation syn-terminator syn-rust\">;</span>\n\n</span></code></pre>"),
+              ("```rust editable\nlet s = \"foo\n ## bar\n\";\n```",
+                "<pre class=\"playground\"><code class=\"language-rust editable\"><span class=\"syn-source syn-rust\"><span class=\"syn-storage syn-type syn-rust\">let</span> s <span class=\"syn-keyword syn-operator syn-assignment syn-rust\">=</span> <span class=\"syn-string syn-quoted syn-double syn-rust\"><span class=\"syn-punctuation syn-definition syn-string syn-begin syn-rust\">&quot;</span>foo\n\n</span></span><span class=\"boring\"><span class=\"syn-source syn-rust\"><span class=\"syn-string syn-quoted syn-double syn-rust\"> # bar\n</span></span></span><span class=\"syn-source syn-rust\"><span class=\"syn-string syn-quoted syn-double syn-rust\"><span class=\"syn-punctuation syn-definition syn-string syn-end syn-rust\">&quot;</span></span><span class=\"syn-punctuation syn-terminator syn-rust\">;</span>\n\n</span></code></pre>"),
+              ("```rust editable\nlet s = \"foo\n # bar\n#\n\";\n```",
+                "<pre class=\"playground\"><code class=\"language-rust editable\"><span class=\"syn-source syn-rust\"><span class=\"syn-storage syn-type syn-rust\">let</span> s <span class=\"syn-keyword syn-operator syn-assignment syn-rust\">=</span> <span class=\"syn-string syn-quoted syn-double syn-rust\"><span class=\"syn-punctuation syn-definition syn-string syn-begin syn-rust\">&quot;</span>foo\n\n</span></span><span class=\"boring\"><span class=\"syn-source syn-rust\"><span class=\"syn-string syn-quoted syn-double syn-rust\"> bar\n</span></span></span><span class=\"syn-source syn-rust\"><span class=\"syn-string syn-quoted syn-double syn-rust\"></span></span><span class=\"boring\"><span class=\"syn-source syn-rust\"><span class=\"syn-string syn-quoted syn-double syn-rust\">\n</span></span></span><span class=\"syn-source syn-rust\"><span class=\"syn-string syn-quoted syn-double syn-rust\"><span class=\"syn-punctuation syn-definition syn-string syn-end syn-rust\">&quot;</span></span><span class=\"syn-punctuation syn-terminator syn-rust\">;</span>\n\n</span></code></pre>"),
+              ("```rust ignore\nlet s = \"foo\n # bar\n\";\n```",
+                "<pre><code class=\"language-rust ignore\"><span class=\"boring\"><span class=\"syn-source syn-rust\"><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-storage syn-type syn-function syn-rust\">fn</span> </span><span class=\"syn-entity syn-name syn-function syn-rust\">main</span></span><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-function syn-parameters syn-rust\"><span class=\"syn-punctuation syn-section syn-parameters syn-begin syn-rust\">(</span></span><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-function syn-parameters syn-rust\"><span class=\"syn-punctuation syn-section syn-parameters syn-end syn-rust\">)</span></span></span></span><span class=\"syn-meta syn-function syn-rust\"> </span><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-block syn-rust\"><span class=\"syn-punctuation syn-section syn-block syn-begin syn-rust\">{</span>\n</span></span></span></span><span class=\"syn-source syn-rust\"><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-block syn-rust\"><span class=\"syn-storage syn-type syn-rust\">let</span> s <span class=\"syn-keyword syn-operator syn-assignment syn-rust\">=</span> <span class=\"syn-string syn-quoted syn-double syn-rust\"><span class=\"syn-punctuation syn-definition syn-string syn-begin syn-rust\">&quot;</span>foo\n\n</span></span></span></span><span class=\"boring\"><span class=\"syn-source syn-rust\"><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-block syn-rust\"><span class=\"syn-string syn-quoted syn-double syn-rust\"> bar\n</span></span></span></span></span><span class=\"syn-source syn-rust\"><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-block syn-rust\"><span class=\"syn-string syn-quoted syn-double syn-rust\"><span class=\"syn-punctuation syn-definition syn-string syn-end syn-rust\">&quot;</span></span><span class=\"syn-punctuation syn-terminator syn-rust\">;</span>\n\n</span></span></span><span class=\"boring\"><span class=\"syn-source syn-rust\"><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-block syn-rust\"><span class=\"syn-punctuation syn-section syn-block syn-end syn-rust\">}</span></span></span>\n</span></span><span class=\"syn-source syn-rust\"></span></code></pre>"),
+              ("```rust editable\n#![no_std]\nlet s = \"foo\";\n #[some_attr]\n```",
+                "<pre class=\"playground\"><code class=\"language-rust editable\"><span class=\"syn-source syn-rust\"><span class=\"syn-meta syn-annotation syn-rust\"><span class=\"syn-punctuation syn-definition syn-annotation syn-rust\">#!</span><span class=\"syn-punctuation syn-section syn-group syn-begin syn-rust\">[</span><span class=\"syn-variable syn-annotation syn-rust\">no_std</span><span class=\"syn-punctuation syn-section syn-group syn-end syn-rust\">]</span></span>\n\n<span class=\"syn-storage syn-type syn-rust\">let</span> s <span class=\"syn-keyword syn-operator syn-assignment syn-rust\">=</span> <span class=\"syn-string syn-quoted syn-double syn-rust\"><span class=\"syn-punctuation syn-definition syn-string syn-begin syn-rust\">&quot;</span>foo<span class=\"syn-punctuation syn-definition syn-string syn-end syn-rust\">&quot;</span></span><span class=\"syn-punctuation syn-terminator syn-rust\">;</span>\n\n <span class=\"syn-meta syn-annotation syn-rust\"><span class=\"syn-punctuation syn-definition syn-annotation syn-rust\">#</span><span class=\"syn-punctuation syn-section syn-group syn-begin syn-rust\">[</span><span class=\"syn-variable syn-annotation syn-rust\">some_attr</span><span class=\"syn-punctuation syn-section syn-group syn-end syn-rust\">]</span></span>\n\n</span></code></pre>"),
+            ];
+            for (src, should_be) in &inputs {
+                let got = render_markdown(
+                    src,
+                    false,
+                    &default_syntaxes(),
+                    &Playground {
+                        editable: true,
+                        ..Playground::default()
+                    },
+                    None,
+                );
+                assert_eq!(&*got, *should_be);
+            }
+        }
+        #[test]
+        fn add_playground_edition2015() {
+            let inputs = [
+              ("```rust\nx()\n```",
+               "<pre class=\"playground\"><code class=\"language-rust edition2015\"><span class=\"boring\"><span class=\"syn-source syn-rust\"><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-storage syn-type syn-function syn-rust\">fn</span> </span><span class=\"syn-entity syn-name syn-function syn-rust\">main</span></span><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-function syn-parameters syn-rust\"><span class=\"syn-punctuation syn-section syn-parameters syn-begin syn-rust\">(</span></span><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-function syn-parameters syn-rust\"><span class=\"syn-punctuation syn-section syn-parameters syn-end syn-rust\">)</span></span></span></span><span class=\"syn-meta syn-function syn-rust\"> </span><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-block syn-rust\"><span class=\"syn-punctuation syn-section syn-block syn-begin syn-rust\">{</span>\n</span></span></span></span><span class=\"syn-source syn-rust\"><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-block syn-rust\"><span class=\"syn-support syn-function syn-rust\">x</span><span class=\"syn-meta syn-group syn-rust\"><span class=\"syn-punctuation syn-section syn-group syn-begin syn-rust\">(</span></span><span class=\"syn-meta syn-group syn-rust\"><span class=\"syn-punctuation syn-section syn-group syn-end syn-rust\">)</span></span>\n\n</span></span></span><span class=\"boring\"><span class=\"syn-source syn-rust\"><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-block syn-rust\"><span class=\"syn-punctuation syn-section syn-block syn-end syn-rust\">}</span></span></span>\n</span></span><span class=\"syn-source syn-rust\"></span></code></pre>"),
+              ("```rust\nfn main() {}\n```",
+               "<pre class=\"playground\"><code class=\"language-rust edition2015\"><span class=\"syn-source syn-rust\"><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-storage syn-type syn-function syn-rust\">fn</span> </span><span class=\"syn-entity syn-name syn-function syn-rust\">main</span></span><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-function syn-parameters syn-rust\"><span class=\"syn-punctuation syn-section syn-parameters syn-begin syn-rust\">(</span></span><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-function syn-parameters syn-rust\"><span class=\"syn-punctuation syn-section syn-parameters syn-end syn-rust\">)</span></span></span></span><span class=\"syn-meta syn-function syn-rust\"> </span><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-block syn-rust\"><span class=\"syn-punctuation syn-section syn-block syn-begin syn-rust\">{</span></span><span class=\"syn-meta syn-block syn-rust\"><span class=\"syn-punctuation syn-section syn-block syn-end syn-rust\">}</span></span></span>\n\n</span></code></pre>"),
+              ("```rust edition2015\nfn main() {}\n```",
+               "<pre class=\"playground\"><code class=\"language-rust edition2015\"><span class=\"syn-source syn-rust\"><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-storage syn-type syn-function syn-rust\">fn</span> </span><span class=\"syn-entity syn-name syn-function syn-rust\">main</span></span><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-function syn-parameters syn-rust\"><span class=\"syn-punctuation syn-section syn-parameters syn-begin syn-rust\">(</span></span><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-function syn-parameters syn-rust\"><span class=\"syn-punctuation syn-section syn-parameters syn-end syn-rust\">)</span></span></span></span><span class=\"syn-meta syn-function syn-rust\"> </span><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-block syn-rust\"><span class=\"syn-punctuation syn-section syn-block syn-begin syn-rust\">{</span></span><span class=\"syn-meta syn-block syn-rust\"><span class=\"syn-punctuation syn-section syn-block syn-end syn-rust\">}</span></span></span>\n\n</span></code></pre>"),
+              ("```rust edition2018\nfn main() {}\n```",
+               "<pre class=\"playground\"><code class=\"language-rust edition2018\"><span class=\"syn-source syn-rust\"><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-storage syn-type syn-function syn-rust\">fn</span> </span><span class=\"syn-entity syn-name syn-function syn-rust\">main</span></span><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-function syn-parameters syn-rust\"><span class=\"syn-punctuation syn-section syn-parameters syn-begin syn-rust\">(</span></span><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-function syn-parameters syn-rust\"><span class=\"syn-punctuation syn-section syn-parameters syn-end syn-rust\">)</span></span></span></span><span class=\"syn-meta syn-function syn-rust\"> </span><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-block syn-rust\"><span class=\"syn-punctuation syn-section syn-block syn-begin syn-rust\">{</span></span><span class=\"syn-meta syn-block syn-rust\"><span class=\"syn-punctuation syn-section syn-block syn-end syn-rust\">}</span></span></span>\n\n</span></code></pre>"),
+            ];
+            for (src, should_be) in &inputs {
+                let got = render_markdown(
+                    src,
+                    false,
+                    &default_syntaxes(),
+                    &Playground {
+                        editable: true,
+                        ..Playground::default()
+                    },
+                    Some(RustEdition::E2015),
+                );
+                assert_eq!(&*got, *should_be);
+            }
+        }
+        #[test]
+        fn add_playground_edition2018() {
+            let inputs = [
+              ("```rust\nx()\n```",
+               "<pre class=\"playground\"><code class=\"language-rust edition2018\"><span class=\"boring\"><span class=\"syn-source syn-rust\"><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-storage syn-type syn-function syn-rust\">fn</span> </span><span class=\"syn-entity syn-name syn-function syn-rust\">main</span></span><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-function syn-parameters syn-rust\"><span class=\"syn-punctuation syn-section syn-parameters syn-begin syn-rust\">(</span></span><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-function syn-parameters syn-rust\"><span class=\"syn-punctuation syn-section syn-parameters syn-end syn-rust\">)</span></span></span></span><span class=\"syn-meta syn-function syn-rust\"> </span><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-block syn-rust\"><span class=\"syn-punctuation syn-section syn-block syn-begin syn-rust\">{</span>\n</span></span></span></span><span class=\"syn-source syn-rust\"><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-block syn-rust\"><span class=\"syn-support syn-function syn-rust\">x</span><span class=\"syn-meta syn-group syn-rust\"><span class=\"syn-punctuation syn-section syn-group syn-begin syn-rust\">(</span></span><span class=\"syn-meta syn-group syn-rust\"><span class=\"syn-punctuation syn-section syn-group syn-end syn-rust\">)</span></span>\n\n</span></span></span><span class=\"boring\"><span class=\"syn-source syn-rust\"><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-block syn-rust\"><span class=\"syn-punctuation syn-section syn-block syn-end syn-rust\">}</span></span></span>\n</span></span><span class=\"syn-source syn-rust\"></span></code></pre>"),
+              ("```rust\nfn main() {}\n```",
+               "<pre class=\"playground\"><code class=\"language-rust edition2018\"><span class=\"syn-source syn-rust\"><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-storage syn-type syn-function syn-rust\">fn</span> </span><span class=\"syn-entity syn-name syn-function syn-rust\">main</span></span><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-function syn-parameters syn-rust\"><span class=\"syn-punctuation syn-section syn-parameters syn-begin syn-rust\">(</span></span><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-function syn-parameters syn-rust\"><span class=\"syn-punctuation syn-section syn-parameters syn-end syn-rust\">)</span></span></span></span><span class=\"syn-meta syn-function syn-rust\"> </span><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-block syn-rust\"><span class=\"syn-punctuation syn-section syn-block syn-begin syn-rust\">{</span></span><span class=\"syn-meta syn-block syn-rust\"><span class=\"syn-punctuation syn-section syn-block syn-end syn-rust\">}</span></span></span>\n\n</span></code></pre>"),
+              ("```rust edition2015\nfn main() {}\n```",
+               "<pre class=\"playground\"><code class=\"language-rust edition2015\"><span class=\"syn-source syn-rust\"><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-storage syn-type syn-function syn-rust\">fn</span> </span><span class=\"syn-entity syn-name syn-function syn-rust\">main</span></span><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-function syn-parameters syn-rust\"><span class=\"syn-punctuation syn-section syn-parameters syn-begin syn-rust\">(</span></span><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-function syn-parameters syn-rust\"><span class=\"syn-punctuation syn-section syn-parameters syn-end syn-rust\">)</span></span></span></span><span class=\"syn-meta syn-function syn-rust\"> </span><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-block syn-rust\"><span class=\"syn-punctuation syn-section syn-block syn-begin syn-rust\">{</span></span><span class=\"syn-meta syn-block syn-rust\"><span class=\"syn-punctuation syn-section syn-block syn-end syn-rust\">}</span></span></span>\n\n</span></code></pre>"),
+              ("```rust edition2018\nfn main() {}\n```",
+               "<pre class=\"playground\"><code class=\"language-rust edition2018\"><span class=\"syn-source syn-rust\"><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-storage syn-type syn-function syn-rust\">fn</span> </span><span class=\"syn-entity syn-name syn-function syn-rust\">main</span></span><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-function syn-parameters syn-rust\"><span class=\"syn-punctuation syn-section syn-parameters syn-begin syn-rust\">(</span></span><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-function syn-parameters syn-rust\"><span class=\"syn-punctuation syn-section syn-parameters syn-end syn-rust\">)</span></span></span></span><span class=\"syn-meta syn-function syn-rust\"> </span><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-block syn-rust\"><span class=\"syn-punctuation syn-section syn-block syn-begin syn-rust\">{</span></span><span class=\"syn-meta syn-block syn-rust\"><span class=\"syn-punctuation syn-section syn-block syn-end syn-rust\">}</span></span></span>\n\n</span></code></pre>"),
+            ];
+            for (src, should_be) in &inputs {
+                let got = render_markdown(
+                    src,
+                    false,
+                    &default_syntaxes(),
+                    &Playground {
+                        editable: true,
+                        ..Playground::default()
+                    },
+                    Some(RustEdition::E2018),
+                );
+                assert_eq!(&*got, *should_be);
+            }
+        }
+        #[test]
+        fn add_playground_edition2021() {
+            let inputs = [
+              ("```rust\nx()\n```",
+               "<pre class=\"playground\"><code class=\"language-rust edition2021\"><span class=\"boring\"><span class=\"syn-source syn-rust\"><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-storage syn-type syn-function syn-rust\">fn</span> </span><span class=\"syn-entity syn-name syn-function syn-rust\">main</span></span><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-function syn-parameters syn-rust\"><span class=\"syn-punctuation syn-section syn-parameters syn-begin syn-rust\">(</span></span><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-function syn-parameters syn-rust\"><span class=\"syn-punctuation syn-section syn-parameters syn-end syn-rust\">)</span></span></span></span><span class=\"syn-meta syn-function syn-rust\"> </span><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-block syn-rust\"><span class=\"syn-punctuation syn-section syn-block syn-begin syn-rust\">{</span>\n</span></span></span></span><span class=\"syn-source syn-rust\"><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-block syn-rust\"><span class=\"syn-support syn-function syn-rust\">x</span><span class=\"syn-meta syn-group syn-rust\"><span class=\"syn-punctuation syn-section syn-group syn-begin syn-rust\">(</span></span><span class=\"syn-meta syn-group syn-rust\"><span class=\"syn-punctuation syn-section syn-group syn-end syn-rust\">)</span></span>\n\n</span></span></span><span class=\"boring\"><span class=\"syn-source syn-rust\"><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-block syn-rust\"><span class=\"syn-punctuation syn-section syn-block syn-end syn-rust\">}</span></span></span>\n</span></span><span class=\"syn-source syn-rust\"></span></code></pre>"),
+              ("```rust\nfn main() {}\n```",
+               "<pre class=\"playground\"><code class=\"language-rust edition2021\"><span class=\"syn-source syn-rust\"><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-storage syn-type syn-function syn-rust\">fn</span> </span><span class=\"syn-entity syn-name syn-function syn-rust\">main</span></span><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-function syn-parameters syn-rust\"><span class=\"syn-punctuation syn-section syn-parameters syn-begin syn-rust\">(</span></span><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-function syn-parameters syn-rust\"><span class=\"syn-punctuation syn-section syn-parameters syn-end syn-rust\">)</span></span></span></span><span class=\"syn-meta syn-function syn-rust\"> </span><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-block syn-rust\"><span class=\"syn-punctuation syn-section syn-block syn-begin syn-rust\">{</span></span><span class=\"syn-meta syn-block syn-rust\"><span class=\"syn-punctuation syn-section syn-block syn-end syn-rust\">}</span></span></span>\n\n</span></code></pre>"),
+              ("```rust edition2015\nfn main() {}\n```",
+               "<pre class=\"playground\"><code class=\"language-rust edition2015\"><span class=\"syn-source syn-rust\"><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-storage syn-type syn-function syn-rust\">fn</span> </span><span class=\"syn-entity syn-name syn-function syn-rust\">main</span></span><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-function syn-parameters syn-rust\"><span class=\"syn-punctuation syn-section syn-parameters syn-begin syn-rust\">(</span></span><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-function syn-parameters syn-rust\"><span class=\"syn-punctuation syn-section syn-parameters syn-end syn-rust\">)</span></span></span></span><span class=\"syn-meta syn-function syn-rust\"> </span><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-block syn-rust\"><span class=\"syn-punctuation syn-section syn-block syn-begin syn-rust\">{</span></span><span class=\"syn-meta syn-block syn-rust\"><span class=\"syn-punctuation syn-section syn-block syn-end syn-rust\">}</span></span></span>\n\n</span></code></pre>"),
+              ("```rust edition2018\nfn main() {}\n```",
+               "<pre class=\"playground\"><code class=\"language-rust edition2018\"><span class=\"syn-source syn-rust\"><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-storage syn-type syn-function syn-rust\">fn</span> </span><span class=\"syn-entity syn-name syn-function syn-rust\">main</span></span><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-function syn-parameters syn-rust\"><span class=\"syn-punctuation syn-section syn-parameters syn-begin syn-rust\">(</span></span><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-function syn-parameters syn-rust\"><span class=\"syn-punctuation syn-section syn-parameters syn-end syn-rust\">)</span></span></span></span><span class=\"syn-meta syn-function syn-rust\"> </span><span class=\"syn-meta syn-function syn-rust\"><span class=\"syn-meta syn-block syn-rust\"><span class=\"syn-punctuation syn-section syn-block syn-begin syn-rust\">{</span></span><span class=\"syn-meta syn-block syn-rust\"><span class=\"syn-punctuation syn-section syn-block syn-end syn-rust\">}</span></span></span>\n\n</span></code></pre>"),
+            ];
+            for (src, should_be) in &inputs {
+                let got = render_markdown(
+                    src,
+                    false,
+                    &default_syntaxes(),
+                    &Playground {
+                        editable: true,
+                        ..Playground::default()
+                    },
+                    Some(RustEdition::E2021),
+                );
+                assert_eq!(&*got, *should_be);
+            }
+        }
+        #[test]
+        fn no_add_playground_to_other_languages() {
+            let inputs = [
+              ("```html,testhtml\n<p>\n```",
+               "<pre><code class=\"language-html testhtml\"><span class=\"syn-text syn-html syn-basic\"><span class=\"syn-meta syn-tag syn-block syn-any syn-html\"><span class=\"syn-punctuation syn-definition syn-tag syn-begin syn-html\">&lt;</span><span class=\"syn-entity syn-name syn-tag syn-block syn-any syn-html\">p</span><span class=\"syn-punctuation syn-definition syn-tag syn-end syn-html\">&gt;</span></span>\n</span></code></pre>"),
+              ("```js es7\nf()\n```",
+               "<pre><code class=\"language-js es7\"><span class=\"syn-source syn-js\"><span class=\"syn-meta syn-function-call syn-without-arguments syn-js\"><span class=\"syn-variable syn-function syn-js\">f</span><span class=\"syn-meta syn-group syn-braces syn-round syn-function syn-arguments syn-js\">()</span></span>\n</span></code></pre>"),
+            ];
+            for (src, should_be) in &inputs {
+                let got = render_markdown(
+                    src,
+                    false,
+                    &default_syntaxes(),
+                    &Playground {
+                        editable: true,
+                        ..Playground::default()
+                    },
+                    Some(RustEdition::E2021),
+                );
+                assert_eq!(&*got, *should_be);
+            }
         }
     }