2 files changed, 29 insertions, 2 deletions
diff --git a/src/main.rs b/src/main.rs
index 89deb49..d484e5e 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,5 +1,6 @@
-use std::io::{self, BufRead, BufReader};
-use std::fs::File;
+use std::io::{self, BufRead, BufReader, Write};
+use std::fs::{File, OpenOptions};
+use std::path::Path;
 
 #[cfg(test)]
 mod tests;
@@ -49,6 +50,12 @@ impl Alias {
         }
     }
 
+    fn write_to_file<P: AsRef<Path>>(&self, file: P) -> Result<(), io::Error> {
+        let mut f = try!(OpenOptions::new().write(true).open(file));
+        try!(f.write_all(self.to_string().as_bytes()));
+        Ok(())
+    }
+
     fn update_alias_id(&mut self, similar_aliases: Vec<String>) {
         if !similar_aliases.is_empty() {
             self.alias = format!("{}-{}", self.alias, similar_aliases.len() + 1);
diff --git a/src/tests.rs b/src/tests.rs
index b3a172c..1034bc6 100644
--- a/src/tests.rs
+++ b/src/tests.rs
@@ -1,3 +1,6 @@
+use std::fs::{self, File};
+use std::io::Read;
+
 use super::{Alias, AliasSearchError, find_alias_in_file};
 
 #[test]
@@ -120,3 +123,20 @@ fn update_alias_id_increments_alias() {
 
     assert_eq!("hooves-derpy-5", &alias.alias);
 }
+
+
+#[test]
+fn alias_write_to_file_must_write_given_alias_to_file() {
+    let alias = update_alias_id_sample_alias();
+
+    let test_file = "./testdata/write_to_file";
+    File::create(test_file).unwrap();
+    alias.write_to_file(test_file).unwrap();
+
+    let mut f = File::open(test_file).unwrap();
+    let mut file_contents = String::new();
+    f.read_to_string(&mut file_contents).unwrap();
+    fs::remove_file(test_file).unwrap();
+
+    assert_eq!(alias.to_string(), file_contents);
+}