Implement 'mdbook test'

Fixes #69

src/bin/mdbook.rs

@@ -33,6 +33,8 @@ fn main() {
                         .arg_from_usage("[dir] 'A directory for your book{n}(Defaults to Current Directory when ommitted)'"))
                     .subcommand(SubCommand::with_name("watch")
                         .about("Watch the files for changes"))
+                    .subcommand(SubCommand::with_name("test")
+                        .about("Test that code samples compile"))
                     .get_matches();
 
     // Check which subcomamnd the user ran...
@@ -40,6 +42,7 @@ fn main() {
         ("init", Some(sub_matches))  => init(sub_matches),
         ("build", Some(sub_matches)) => build(sub_matches),
         ("watch", _)                 => unimplemented!(),
+        ("test", Some(sub_matches)) => test(sub_matches),
         (_, _)                       => unreachable!()
     };
 
@@ -104,6 +107,15 @@ fn build(args: &ArgMatches) -> Result<(), Box<Error>> {
     Ok(())
 }
 
+fn test(args: &ArgMatches) -> Result<(), Box<Error>> {
+    let book_dir = get_book_dir(args);
+    let mut book = MDBook::new(&book_dir).read_config();
+
+    try!(book.test());
+
+    Ok(())
+}
+
 fn get_book_dir(args: &ArgMatches) -> PathBuf {
     if let Some(dir) = args.value_of("dir") {
         // Check if path is relative from current dir, or absolute...

src/book/mdbook.rs

@@ -1,7 +1,10 @@
 use std::path::{Path, PathBuf};
 use std::fs::{self, File};
-use std::io::Write;
 use std::error::Error;
+use std::io;
+use std::io::Write;
+use std::io::ErrorKind;
+use std::process::Command;
 
 use {BookConfig, BookItem, theme, parse, utils};
 use book::BookItems;
@@ -257,6 +260,39 @@ impl MDBook {
         self
     }
 
+    pub fn test(&mut self) -> Result<(), Box<Error>> {
+        // read in the chapters
+        try!(self.parse_summary());
+        for item in self.iter() {
+
+            match *item {
+                BookItem::Chapter(_, ref ch) => {
+                    if ch.path != PathBuf::new() {
+
+                        let path = self.get_src().join(&ch.path);
+
+                        println!("[*]: Testing file: {:?}", path);
+
+                        let output_result = Command::new("rustdoc")
+                            .arg(&path)
+                            .arg("--test")
+                            .output();
+                        let output = try!(output_result);
+
+                        if !output.status.success() {
+                            return Err(Box::new(io::Error::new(ErrorKind::Other, format!(
+                                            "{}\n{}",
+                                            String::from_utf8_lossy(&output.stdout),
+                                            String::from_utf8_lossy(&output.stderr)))) as Box<Error>);
+                        }
+                    }
+                }
+                _ => {}
+            }
+        }
+        Ok(())
+    }
+
     pub fn set_dest(mut self, dest: &Path) -> Self {
 
         // Handle absolute and relative paths