Can remove files and directories.

tests/helpers/mod.rs

@@ -1,11 +1,13 @@
-use std::path::PathBuf;
+#![allow(dead_code)]
+
+pub use std::path::PathBuf;
 
 #[macro_export]
 macro_rules! nu {
     ($out:ident, $cwd:expr, $commands:expr) => {
-        use std::error::Error;
-        use std::io::prelude::*;
-        use std::process::{Command, Stdio};
+        pub use std::io::prelude::*;
+        pub use std::process::{Command, Stdio};
+        pub use std::error::Error;
 
         let commands = &*format!(
             "
@@ -75,6 +77,22 @@ macro_rules! nu_error {
     };
 }
 
+pub fn create_file_at(full_path: &str) {
+    std::fs::write(PathBuf::from(full_path), "fake data".as_bytes()).expect("can not create file");
+}
+
+pub fn file_exists_at(full_path: &str) -> bool {
+    PathBuf::from(full_path).exists()
+}
+
+pub fn delete_directory_at(full_path: &str) {
+    std::fs::remove_dir_all(PathBuf::from(full_path)).expect("can not remove directory");
+}
+
+pub fn create_directory_at(full_path: &str) {
+    std::fs::create_dir(PathBuf::from(full_path)).expect("can not create directory");
+}
+
 pub fn executable_path() -> PathBuf {
     let mut buf = PathBuf::new();
     buf.push("target");