safe-ios/Packages/Ethereum/Tests/SolidityTests/FixedPointEncodingTests.swift

//
//  File.swift
//  
//
//  Created by Dmitry Bespalov on 03.01.22.
//

import Foundation
import Solidity
import XCTest

class FixedPointEncodingTests: XCTestCase {
    func testEncodeUFixed8x18() {
        let value = Sol.UnsignedFixedPoint(storage: Sol.UInt8(0xef), exponent: 18)
        let data = value.encode()
        let expected = Data([
            0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // 16 bytes
            0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xef, // 32 bytes
        ])
        XCTAssertEqual(data, expected)
    }

    func testDecodeUFixed248x18() throws {
        let data = Data([
            0xaa, // extra byte to simulate start from the middle
            0x00, 0xef, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // 16 bytes
            0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xaa, // 32 bytes
        ])
        let expected = Sol.UnsignedFixedPoint(
            storage: Sol.UInt248("ef0000000000000000000000000000000000000000000000000000000000aa", radix: 16)!,
            exponent: 18)

        var offset: Int = 1
        var decoded = Sol.UnsignedFixedPoint(storage: Sol.UInt248(), exponent: 18)
        try decoded.decode(from: data, offset: &offset)
        XCTAssertEqual(decoded, expected)
        XCTAssertEqual(offset, 33)
    }

    func testEncodeFixed128x18() {
        let value = Sol.SignedFixedPoint(storage: Sol.Int128(-3), exponent: 18)
        let data = value.encode()
        let expected = Data([
            0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, // 16 bytes
            0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xfd, // 32 bytes
        ])
        XCTAssertEqual(Array(data), Array(expected))
    }

    func testDecodeFixed128x18() throws {
        let expected = Sol.SignedFixedPoint(storage: Sol.Int128(-3), exponent: 18)
        let data = Data([
            0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, // 16 bytes
            0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xfd, // 32 bytes
        ])

        var decoded = Sol.SignedFixedPoint(storage: Sol.Int128(), exponent: 18)
        var offset: Int = 0
        try decoded.decode(from: data, offset: &offset)
        XCTAssertEqual(decoded, expected)
    }
}