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

This reverts commit a7b3aa0444c8b4020e68d009180068b1c1b4fd92.

1 files changed, 6 insertions, 12 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(