add derive/rename tests

tests/derive.rs

@@ -0,0 +1,34 @@
+#[macro_use]
+extern crate optional_struct;
+
+#[derive(OptionalStruct)]
+#[optional_derive(Debug, Clone, PartialEq)]
+struct Config {
+    delay: Option<u32>,
+    path: String,
+    percentage: f32,
+}
+
+#[test]
+fn test_apply_options() {
+    let mut config = Config {
+        delay: Some(2),
+        path: "/var/log/foo.log".to_owned(),
+        percentage: 3.12,
+    };
+
+    let opt_config = OptionalConfig {
+        delay: None,
+        path: Some("/tmp/bar.log".to_owned()),
+        percentage: Some(42.24),
+    };
+
+    let cloned = opt_config.clone();
+
+    assert_eq!(opt_config, cloned);
+
+    config.apply_options(opt_config);
+    assert_eq!(config.delay, None);
+    assert_eq!(config.path, "/tmp/bar.log");
+    assert_eq!(config.percentage, 42.24);
+}

tests/renamed.rs

@@ -0,0 +1,31 @@
+#[macro_use]
+extern crate optional_struct;
+
+#[derive(OptionalStruct)]
+#[optional_name = "Woof"]
+struct Config {
+    delay: Option<u32>,
+    path: String,
+    percentage: f32,
+}
+
+#[test]
+fn test_apply_options() {
+    let mut config = Config {
+        delay: Some(2),
+        path: "/var/log/foo.log".to_owned(),
+        percentage: 3.12,
+    };
+
+    let opt_config = Woof {
+        delay: None,
+        path: Some("/tmp/bar.log".to_owned()),
+        percentage: Some(42.24),
+    };
+
+    config.apply_options(opt_config);
+
+    assert_eq!(config.delay, None);
+    assert_eq!(config.path, "/tmp/bar.log");
+    assert_eq!(config.percentage, 42.24);
+}