feat: set environment variable

Author: codinaut

Cargo.toml

@@ -6,4 +6,5 @@ edition = "2018"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
-[dependencies]
+[dev-dependencies]
+fake = "2.2.3"

src/lib.rs

@@ -1,7 +1 @@
-#[cfg(test)]
-mod tests {
-    #[test]
-    fn it_works() {
-        assert_eq!(2 + 2, 4);
-    }
-}
+mod testkit;

src/testkit.rs

@@ -0,0 +1,24 @@
+use std::env;
+use std::ffi::{OsStr, OsString};
+
+pub struct EnvironmentTestGuard {}
+
+pub fn set_env<V: AsRef<OsStr>>(key: OsString, value: V) {
+    env::set_var(key, value)
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+    use fake::faker::lorem::en::*;
+    use fake::Fake;
+
+    #[test]
+    fn set_env_ok() {
+        let key = OsString::from(Word().fake::<String>());
+        let value = OsString::from(Sentence(1..10).fake::<String>());
+
+        set_env(key.clone(), &value);
+        assert_eq!(env::var_os(key).unwrap(), value)
+    }
+}