miniserde 0.1.28

use crate::de::{Deserialize, Seq, Visitor};
use crate::error::Result;
use crate::json::{drop, Value};
use crate::private;
use crate::ser::{Fragment, Serialize};
use crate::Place;
use alloc::boxed::Box;
use alloc::vec::Vec;
use core::fmt::{self, Debug};
use core::iter::FromIterator;
use core::mem::{self, ManuallyDrop};
use core::ops::{Deref, DerefMut};
use core::ptr;

/// A `Vec<Value>` with a non-recursive drop impl.
#[derive(Clone, Default)]
pub struct Array {
    inner: Vec<Value>,
}

impl Drop for Array {
    fn drop(&mut self) {
        self.inner.drain(..).for_each(drop::safely);
    }
}

fn take(array: Array) -> Vec<Value> {
    let array = ManuallyDrop::new(array);
    unsafe { ptr::read(&array.inner) }
}

impl Array {
    pub fn new() -> Self {
        Array { inner: Vec::new() }
    }
}

impl Deref for Array {
    type Target = Vec<Value>;

    fn deref(&self) -> &Self::Target {
        &self.inner
    }
}

impl DerefMut for Array {
    fn deref_mut(&mut self) -> &mut Self::Target {
        &mut self.inner
    }
}

impl IntoIterator for Array {
    type Item = Value;
    type IntoIter = <Vec<Value> as IntoIterator>::IntoIter;

    fn into_iter(self) -> Self::IntoIter {
        take(self).into_iter()
    }
}

impl<'a> IntoIterator for &'a Array {
    type Item = &'a Value;
    type IntoIter = <&'a Vec<Value> as IntoIterator>::IntoIter;

    fn into_iter(self) -> Self::IntoIter {
        self.iter()
    }
}

impl<'a> IntoIterator for &'a mut Array {
    type Item = &'a mut Value;
    type IntoIter = <&'a mut Vec<Value> as IntoIterator>::IntoIter;

    fn into_iter(self) -> Self::IntoIter {
        self.iter_mut()
    }
}

impl FromIterator<Value> for Array {
    fn from_iter<I>(iter: I) -> Self
    where
        I: IntoIterator<Item = Value>,
    {
        Array {
            inner: Vec::from_iter(iter),
        }
    }
}

impl Debug for Array {
    fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
        formatter.write_str("Array ")?;
        formatter.debug_list().entries(self).finish()
    }
}

impl Serialize for Array {
    fn begin(&self) -> Fragment {
        private::stream_slice(self)
    }
}

impl Deserialize for Array {
    fn begin(out: &mut Option<Self>) -> &mut dyn Visitor {
        impl Visitor for Place<Array> {
            fn seq(&mut self) -> Result<Box<dyn Seq + '_>> {
                Ok(Box::new(ArrayBuilder {
                    out: &mut self.out,
                    array: Array::new(),
                    element: None,
                }))
            }
        }

        struct ArrayBuilder<'a> {
            out: &'a mut Option<Array>,
            array: Array,
            element: Option<Value>,
        }

        impl<'a> ArrayBuilder<'a> {
            fn shift(&mut self) {
                if let Some(e) = self.element.take() {
                    self.array.push(e);
                }
            }
        }

        impl<'a> Seq for ArrayBuilder<'a> {
            fn element(&mut self) -> Result<&mut dyn Visitor> {
                self.shift();
                Ok(Deserialize::begin(&mut self.element))
            }

            fn finish(&mut self) -> Result<()> {
                self.shift();
                *self.out = Some(mem::replace(&mut self.array, Array::new()));
                Ok(())
            }
        }

        Place::new(out)
    }
}