Require Rust 2021 edition

This allows us to clean up and simplify the code.

Author: Dylan-DPC

.github/workflows/main.yml

@@ -31,8 +31,7 @@ jobs:
             rust: stable
           - build: msrv
             os: ubuntu-latest
-            # sync MSRV with docs: guide/src/guide/installation.md
-            rust: 1.54.0
+            rust: 1.56.0
     steps:
     - uses: actions/checkout@master
     - name: Install Rust

Cargo.toml

@@ -7,7 +7,7 @@ authors = [
     "Matt Ickstadt <mattico8@gmail.com>"
 ]
 documentation = "http://rust-lang.github.io/mdBook/index.html"
-edition = "2018"
+edition = "2021"
 exclude = ["/guide/*"]
 keywords = ["book", "gitbook", "rustbook", "markdown"]
 license = "MPL-2.0"

src/book/book.rs

@@ -8,7 +8,7 @@ use super::summary::{parse_summary, Link, SectionNumber, Summary, SummaryItem};
 use crate::config::BuildConfig;
 use crate::errors::*;
 use crate::utils::bracket_escape;
-
+use log::debug;
 use serde::{Deserialize, Serialize};
 
 /// Load a book into memory from its `src/` directory.

src/book/init.rs

@@ -6,6 +6,7 @@ use super::MDBook;
 use crate::config::Config;
 use crate::errors::*;
 use crate::theme;
+use log::{debug, error, info, trace};
 
 /// A helper for setting up a new book and its directory structure.
 #[derive(Debug, Clone, PartialEq)]

src/book/mod.rs

@@ -14,6 +14,7 @@ pub use self::book::{load_book, Book, BookItem, BookItems, Chapter};
 pub use self::init::BookBuilder;
 pub use self::summary::{parse_summary, Link, SectionNumber, Summary, SummaryItem};
 
+use log::{debug, error, info, log_enabled, trace, warn};
 use std::io::Write;
 use std::path::PathBuf;
 use std::process::Command;

src/book/summary.rs

@@ -1,4 +1,5 @@
 use crate::errors::*;
+use log::{debug, trace, warn};
 use memchr::{self, Memchr};
 use pulldown_cmark::{self, Event, HeadingLevel, Tag};
 use serde::{Deserialize, Serialize};

src/config.rs

@@ -49,6 +49,7 @@
 
 #![deny(missing_docs)]
 
+use log::{debug, trace, warn};
 use serde::{Deserialize, Deserializer, Serialize, Serializer};
 use std::collections::HashMap;
 use std::env;
@@ -295,7 +296,7 @@ impl Default for Config {
     }
 }
 
-impl<'de> Deserialize<'de> for Config {
+impl<'de> serde::Deserialize<'de> for Config {
     fn deserialize<D: Deserializer<'de>>(de: D) -> std::result::Result<Self, D::Error> {
         let raw = Value::deserialize(de)?;
 
@@ -717,6 +718,7 @@ impl<'de, T> Updateable<'de> for T where T: Serialize + Deserialize<'de> {}
 mod tests {
     use super::*;
     use crate::utils::fs::get_404_output_file;
+    use serde_json::json;
 
     const COMPLEX_CONFIG: &str = r#"
         [book]

src/lib.rs

@@ -83,17 +83,6 @@
 #![deny(missing_docs)]
 #![deny(rust_2018_idioms)]
 
-#[macro_use]
-extern crate lazy_static;
-#[macro_use]
-extern crate log;
-#[macro_use]
-extern crate serde_json;
-
-#[cfg(test)]
-#[macro_use]
-extern crate pretty_assertions;
-
 pub mod book;
 pub mod config;
 pub mod preprocess;

src/preprocess/cmd.rs

@@ -1,6 +1,7 @@
 use super::{Preprocessor, PreprocessorContext};
 use crate::book::Book;
 use crate::errors::*;
+use log::{debug, trace, warn};
 use shlex::Shlex;
 use std::io::{self, Read, Write};
 use std::process::{Child, Command, Stdio};

src/preprocess/index.rs

@@ -1,10 +1,11 @@
 use regex::Regex;
 use std::path::Path;
 
-use crate::errors::*;
-
 use super::{Preprocessor, PreprocessorContext};
 use crate::book::{Book, BookItem};
+use crate::errors::*;
+use lazy_static::lazy_static;
+use log::warn;
 
 /// A preprocessor for converting file name `README.md` to `index.md` since
 /// `README.md` is the de facto index file in markdown-based documentation.