ethabi 2.0.1

Easy to use conversion of ethereum contract calls to bytecode.
Documentation 
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//! Utils used by different modules.

use error::Error;

/// Convers vector of bytes with len equal n * 32, to a vector of slices.
pub fn slice_data(data: Vec<u8>) -> Result<Vec<[u8; 32]>, Error> {
	if data.len() % 32 != 0 {
		return Err(Error::InvalidData);
	}

	let times = data.len() / 32;
	let mut result = vec![];
	for i in 0..times {
		let mut slice = [0u8; 32];
		let offset = 32 * i;
		slice.copy_from_slice(&data[offset..offset + 32]);
		result.push(slice);
	}
	Ok(result)
}

/// Converts u32 to right aligned array of 32 bytes.
pub fn pad_u32(value: u32) -> [u8; 32] {
	let mut padded = [0u8; 32];
	padded[28] = (value >> 24) as u8;
	padded[29] = (value >> 16) as u8;
	padded[30] = (value >> 8) as u8;
	padded[31] = value as u8;
	padded
}

/// Converts i32 to right aligned array of 32 bytes.
pub fn pad_i32(value: i32) -> [u8; 32] {
	if value >= 0 {
		return pad_u32(value as u32);
	}

	let mut padded = [0xffu8; 32];
	padded[28] = (value >> 24) as u8;
	padded[29] = (value >> 16) as u8;
	padded[30] = (value >> 8) as u8;
	padded[31] = value as u8;
	padded
}

#[cfg(test)]
mod tests {
	use hex::FromHex;
	use super::pad_i32;

	#[test]
	fn test_i32() {
		assert_eq!("0000000000000000000000000000000000000000000000000000000000000000".from_hex().unwrap(), pad_i32(0).to_vec());
		assert_eq!("ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff".from_hex().unwrap(), pad_i32(-1).to_vec());
		assert_eq!("fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffe".from_hex().unwrap(), pad_i32(-2).to_vec());
		assert_eq!("ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff00".from_hex().unwrap(), pad_i32(-256).to_vec());
	}
}