invade 0.0.2

A library to reflect on Rust types and generate code
Documentation 
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use std::{any::Any, str};

pub use invade_derive::*;

pub type AccessHelper = for<'a, 'b> fn(&'a dyn Any) -> dyn Any;

pub struct Field<'a, Element: Sized> {
    pub name: String,
    pub get_ptr: Option<fn(&'a Element) -> &'a dyn Any>,
    pub set_ptr: Option<fn(&'a mut Element, Box<dyn Any>)>,
}

pub struct Method<'a, Element: Sized> {
    pub name: String,
    pub ptr: Option<fn(&'a mut Element, Box<dyn Any>)>,
}

pub struct Invaded<'a, Element: Sized> {
    value: Element,
    fields: Vec<Field<'a, Element>>,
    methods: Vec<Method<'a, Element>>,
}

impl<'a, Element> Invaded<'a, Element> {
    pub fn new(
        value: Element,
        fields: Vec<Field<'a, Element>>,
        methods: Vec<Method<'a, Element>>,
    ) -> Self {
        Self {
            value,
            fields,
            methods,
        }
    }

    pub fn set<T: Any + Send + Sync>(&'a mut self, name: &str, value: T) {
        let field = self.fields.iter().find(|field| field.name == name);

        if let Some(field) = field {
            if let Some(ptr) = field.set_ptr {
                ptr(&mut self.value, Box::new(value));
            }
        }
    }

    pub fn get<T: Any + Send + Sync + Clone>(&'a self, name: &str) -> Option<T> {
        let field = self.fields.iter().find(|field| field.name == name);

        if let Some(field) = field {
            if let Some(ptr) = field.get_ptr {
                let value = ptr(&self.value);
                let value = value.downcast_ref::<T>();

                return value.cloned();
            }
        }

        None
    }

    pub fn call(&'a mut self, name: &str) {
        let method = self.methods.iter().find(|method| method.name == name);

        if let Some(method) = method {
            if let Some(ptr) = method.ptr {
                ptr(&mut self.value, Box::new(()));
            }
        }
    }

    pub fn restore(self) -> Element {
        self.value
    }
}

#[cfg(test)]
mod tests {
    use super::*;

    struct Test {
        name: String,
        age: i32,
    }

    impl Test {
        fn grow(&mut self) {
            self.age += 1;
        }
    }

    #[test]
    fn test_field() {
        let mut test = Test {
            name: "test".to_string(),
            age: 20,
        };
        let invaded = Invaded::new(
            &mut test,
            vec![
                Field {
                    name: "name".to_string(),
                    get_ptr: Some(|test| &test.name as &dyn Any),
                    set_ptr: Some(|test, value| test.name = *value.downcast::<String>().unwrap()),
                },
                Field {
                    name: "age".to_string(),
                    get_ptr: Some(|test| &test.age as &dyn Any),
                    set_ptr: Some(|test, value| test.age = *value.downcast::<i32>().unwrap()),
                },
            ],
            vec![],
        );

        assert_eq!(invaded.get::<String>("name"), Some("test".to_string()));
        assert_eq!(invaded.get::<i32>("age"), Some(20));
    }

    #[test]
    fn test_methods() {
        let mut test = Test {
            name: "test".to_string(),
            age: 20,
        };

        let mut invaded = Invaded::new(
            &mut test,
            vec![Field {
                name: "age".to_string(),
                get_ptr: Some(|test| &test.age as &dyn Any),
                set_ptr: Some(|test, value| test.age = *value.downcast::<i32>().unwrap()),

            }],
            vec![Method {
                name: "grow".to_string(),
                ptr: Some(|test, _| {
                    test.grow();
                }),
            }],
        );

        invaded.call("grow");


        let invaded = Invaded::new(
            &mut test,
            vec![
                Field {
                    name: "name".to_string(),
                    get_ptr: Some(|test| &test.name as &dyn Any),
                    set_ptr: Some(|test, value| test.name = *value.downcast::<String>().unwrap()),
                },
                Field {
                    name: "age".to_string(),
                    get_ptr: Some(|test| &test.age as &dyn Any),
                    set_ptr: Some(|test, value| test.age = *value.downcast::<i32>().unwrap()),
                },
            ],
            vec![],
        );

        assert_eq!(invaded.get::<i32>("age"), Some(21));
    }
}