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// Copyright 2020. The Tari Project
//
// Redistribution and use in source and binary forms, with or without modification, are permitted provided that the
// following conditions are met:
//
// 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following
// disclaimer.
//
// 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the
// following disclaimer in the documentation and/or other materials provided with the distribution.
//
// 3. Neither the name of the copyright holder nor the names of its contributors may be used to endorse or promote
// products derived from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
// INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
// WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
// USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

use std::convert::TryInto;

/// Tries to convert a series of `T`s to `U`s, returning an error at the first failure
pub fn try_convert_all<T, U, I>(into_iter: I) -> Result<Vec<U>, T::Error>
where
    I: IntoIterator<Item = T>,
    T: TryInto<U>,
{
    let iter = into_iter.into_iter();
    let mut result = Vec::with_capacity(iter.size_hint().0);
    for item in iter {
        result.push(item.try_into()?);
    }
    Ok(result)
}

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

    #[test]
    fn convert_all() {
        let a: Vec<u32> = try_convert_all(vec![1i64, 2, 3, 4, 5]).unwrap();
        assert_eq!(a, [1, 2, 3, 4, 5]);
    }

    #[test]
    fn convert_all_failed() {
        let err = try_convert_all::<_, u32, _>(vec![std::i64::MAX, 2, 3, 4, 5]).unwrap_err();
        assert_eq!(err.to_string(), "out of range integral type conversion attempted");
    }
}