partially 0.2.1

Provides the Partial trait, and an optional macro to mirror a struct, wrapping each field in an Option
Documentation 
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use partially::Partial;

struct Base {
    value: String,
}

#[derive(Default)]
struct PartialBase {
    value: Option<String>,
}

impl partially::Partial for Base {
    type Item = PartialBase;

    #[allow(clippy::useless_conversion)]
    fn apply_some(&mut self, partial: Self::Item) -> bool {
        let will_apply_some = partial.value.is_some();

        if let Some(value) = partial.value {
            self.value = value.into();
        }

        will_apply_some
    }
}

impl partially::Partial for PartialBase {
    type Item = PartialBase;

    fn apply_some(&mut self, partial: Self::Item) -> bool {
        let will_apply_some = partial.value.is_some();

        if let Some(value) = partial.value {
            self.value = value.into();
        }

        will_apply_some
    }
}

#[test]
fn basic_apply() {
    let empty_partial = PartialBase::default();
    let full_partial = PartialBase {
        value: Some("modified".to_string()),
    };

    let mut data = Base {
        value: "initial".to_string(),
    };

    assert!(!data.apply_some(empty_partial));

    assert_eq!(data.value, "initial".to_string());

    assert!(data.apply_some(full_partial));

    assert_eq!(data.value, "modified".to_string());
}

#[test]
fn partial_apply() {
    let mut empty_partial = PartialBase::default();
    let full_partial = PartialBase {
        value: Some("modified".to_string()),
    };

    assert!(empty_partial.apply_some(full_partial));

    assert_eq!(empty_partial.value, Some("modified".to_string()));
}