feat(test): add an example on how to test a module (#276)

allowed_bindings.rs

@@ -260,5 +260,6 @@ bind! {
     zend_eval_string,
     zend_file_handle,
     zend_stream_init_filename,
-    php_execute_script
+    php_execute_script,
+    zend_register_module_ex
 }

tests/module.rs

@@ -0,0 +1,44 @@
+#![cfg_attr(windows, feature(abi_vectorcall))]
+extern crate ext_php_rs;
+
+#[cfg(feature = "embed")]
+use ext_php_rs::embed::Embed;
+#[cfg(feature = "embed")]
+use ext_php_rs::ffi::zend_register_module_ex;
+use ext_php_rs::prelude::*;
+
+#[test]
+#[cfg(feature = "embed")]
+fn test_module() {
+    Embed::run(|| {
+        // Allow to load the module
+        unsafe { zend_register_module_ex(get_module()) };
+
+        let result = Embed::eval("$foo = hello_world('foo');");
+
+        assert!(result.is_ok());
+
+        let zval = result.unwrap();
+
+        assert!(zval.is_string());
+
+        let string = zval.string().unwrap();
+
+        assert_eq!(string.to_string(), "Hello, foo!");
+    });
+}
+
+/// Gives you a nice greeting!
+///
+/// @param string $name Your name.
+///
+/// @return string Nice greeting!
+#[php_function]
+pub fn hello_world(name: String) -> String {
+    format!("Hello, {}!", name)
+}
+
+#[php_module]
+pub fn module(module: ModuleBuilder) -> ModuleBuilder {
+    module
+}