Generate simple .gitignore on init

src/book/mdbook.rs

@@ -100,6 +100,32 @@ impl MDBook {
             output!("{:?} created", self.config.get_root());
         }
 
+        {
+            let root = self.config.get_root();
+            let gitignore = root.join(".gitignore");
+
+            if !gitignore.exists() {
+
+                // Gitignore does not exist, create it
+
+                debug!("[*]: {:?} does not exist, trying to create .gitignore", root.join(".gitignore"));
+
+                let dest = self.config.get_dest();
+                // `relative_from` is marked as unstable
+                // http://doc.rust-lang.org/std/path/struct.PathBuf.html#method.relative_from
+                let dest = dest.relative_from(root)
+                    .expect("Destination path does not start with root path.");
+                let dest = dest.to_str()
+                    .expect("No destination path found.");
+
+                let mut f = try!(File::create(&root.join(".gitignore")));
+
+                debug!("[*]: Writing to .gitignore");
+
+                try!(writeln!(f, "{}", dest));
+            }
+        }
+
         {
             let dest = self.config.get_dest();
             let src = self.config.get_src();

src/lib.rs

@@ -69,6 +69,9 @@
 //!
 //! Make sure to take a look at it.
 
+// Used in `MDBook.init()`
+#![feature(path_relative_from)]
+
 #[macro_use]
 pub mod macros;
 pub mod book;