Revert "Add support for Rust edition 2018 in playpens (#1086)" (#1093)

This reverts commit a7b3aa0444c8b4020e68d009180068b1c1b4fd92.

3 files changed, 15 insertions, 94 deletions

diff --git a/src/book/mod.rs b/src/book/mod.rs
index 29d2dc3d..8d69eea2 100644
--- a/src/book/mod.rs
+++ b/src/book/mod.rs
@@ -27,7 +27,7 @@ use crate::preprocess::{
 use crate::renderer::{CmdRenderer, HtmlHandlebars, MarkdownRenderer, RenderContext, Renderer};
 use crate::utils;
 
-use crate::config::{Config, RustEdition};
+use crate::config::Config;
 
 /// The object used to manage and build a book.
 pub struct MDBook {
@@ -262,17 +262,11 @@ impl MDBook {
                     let mut tmpf = utils::fs::create_file(&path)?;
                     tmpf.write_all(ch.content.as_bytes())?;
 
-                    let mut cmd = Command::new("rustdoc");
-
-                    cmd.arg(&path).arg("--test").args(&library_args);
-
-                    if let Some(html_cfg) = self.config.html_config() {
-                        if html_cfg.playpen.edition == RustEdition::E2018 {
-                            cmd.args(&["--edition", "2018"]);
-                        }
-                    }
-
-                    let output = cmd.output()?;
+                    let output = Command::new("rustdoc")
+                        .arg(&path)
+                        .arg("--test")
+                        .args(&library_args)
+                        .output()?;
 
                     if !output.status.success() {
                         bail!(ErrorKind::Subprocess(
diff --git a/src/config.rs b/src/config.rs
index 4c8624a6..fae3da84 100644
--- a/src/config.rs
+++ b/src/config.rs
@@ -513,8 +513,6 @@ pub struct Playpen {
     pub copy_js: bool,
     /// Display line numbers on playpen snippets. Default: `false`.
     pub line_numbers: bool,
-    /// Rust edition to use for the code. Default: `2015`.
-    pub edition: RustEdition,
 }
 
 impl Default for Playpen {
@@ -524,66 +522,10 @@ impl Default for Playpen {
             copyable: true,
             copy_js: true,
             line_numbers: false,
-            edition: RustEdition::E2015,
         }
     }
 }
 
-#[derive(Debug, Clone, PartialEq)]
-/// The edition of Rust used in a playpen code snippet
-pub enum RustEdition {
-    /// The 2018 edition of Rust
-    E2018,
-    /// The 2015 edition of Rust
-    E2015,
-}
-
-impl Default for RustEdition {
-    fn default() -> Self {
-        RustEdition::E2015
-    }
-}
-
-impl Serialize for RustEdition {
-    fn serialize<S>(&self, serializer: S) -> std::result::Result<S::Ok, S::Error>
-    where
-        S: Serializer,
-    {
-        match self {
-            RustEdition::E2015 => serializer.serialize_str("2015"),
-            RustEdition::E2018 => serializer.serialize_str("2018"),
-        }
-    }
-}
-
-impl<'de> Deserialize<'de> for RustEdition {
-    fn deserialize<D>(de: D) -> std::result::Result<Self, D::Error>
-    where
-        D: Deserializer<'de>,
-    {
-        use serde::de::Error;
-
-        let raw = Value::deserialize(de)?;
-
-        let edition = match raw {
-            Value::String(s) => s,
-            _ => {
-                return Err(D::Error::custom("Rust edition should be a string"));
-            }
-        };
-
-        let edition = match edition.as_str() {
-            "2018" => RustEdition::E2018,
-            "2015" => RustEdition::E2015,
-            _ => {
-                return Err(D::Error::custom("Unknown Rust edition"));
-            }
-        };
-
-        Ok(edition)
-    }
-}
-
 /// Configuration of the search functionality of the HTML renderer.
 #[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
 #[serde(default, rename_all = "kebab-case")]
@@ -688,7 +630,6 @@ mod tests {
         [output.html.playpen]
         editable = true
         editor = "ace"
-        edition = "2018"
 
         [preprocessor.first]
 
@@ -717,7 +658,6 @@ mod tests {
             copyable: true,
             copy_js: true,
             line_numbers: false,
-            edition: RustEdition::E2018,
         };
         let html_should_be = HtmlConfig {
             curly_quotes: true,
diff --git a/src/renderer/html_handlebars/hbs_renderer.rs b/src/renderer/html_handlebars/hbs_renderer.rs
index aa2bdcc9..0be92562 100644
--- a/src/renderer/html_handlebars/hbs_renderer.rs
+++ b/src/renderer/html_handlebars/hbs_renderer.rs
@@ -1,5 +1,5 @@
 use crate::book::{Book, BookItem};
-use crate::config::{Config, HtmlConfig, Playpen, RustEdition};
+use crate::config::{Config, HtmlConfig, Playpen};
 use crate::errors::*;
 use crate::renderer::html_handlebars::helpers;
 use crate::renderer::{RenderContext, Renderer};
@@ -608,27 +608,14 @@ fn add_playpen_pre(html: &str, playpen_config: &Playpen) -> String {
             let classes = &caps[2];
             let code = &caps[3];
 
-
-            if (classes.contains("language-rust")
-                && !classes.contains("ignore")
-                && !classes.contains("noplaypen"))
-                || classes.contains("mdbook-runnable")
-            {
-                let mut classes = classes.to_string();
-                match playpen_config.edition {
-                    RustEdition::E2018 => classes += " edition2018",
-                    _ => (),
-                }
-
-                // wrap the contents in an external pre block
-                format!(
-                    "<pre class=\"playpen\"><code class=\"{}\">{}</code></pre>",
-                    classes,
-                    {
-                        let content: Cow<'_, str> = if playpen_config.editable
-                            && classes.contains("editable")
-                            || text.contains("fn main")
-                            || text.contains("quick_main!")
+            if classes.contains("language-rust") {
+                if (!classes.contains("ignore") && !classes.contains("noplaypen"))
+                    || classes.contains("mdbook-runnable")
+                {
+                    // wrap the contents in an external pre block
+                    format!(
+                        "<pre class=\"playpen\"><code class=\"{}\">{}</code></pre>",
+                        classes,
                         {
                             let content: Cow<'_, str> = if playpen_config.editable
                                 && classes.contains("editable")