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// Translated from C to Rust. The original C code can be found at
// https://github.com/ulfjack/ryu and carries the following license:
//
// Copyright 2018 Ulf Adams
//
// The contents of this file may be used under the terms of the Apache License,
// Version 2.0.
//
// (See accompanying file LICENSE-Apache or copy at
//
// Alternatively, the contents of this file may be used under the terms of
// the Boost Software License, Version 1.0.
// (See accompanying file LICENSE-Boost or copy at
//
// Unless required by applicable law or agreed to in writing, this software
// is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
// KIND, either express or implied.
#![allow(
clippy::approx_constant,
clippy::float_cmp,
clippy::non_ascii_literal,
clippy::unreadable_literal,
clippy::unseparated_literal_suffix
)]
#[macro_use]
mod macros;
use std::f32;
fn pretty(f: f32) -> String {
ryu::Buffer::new().format(f).to_owned()
}
#[test]
fn test_ryu() {
check!(0.3);
check!(1234000000000.0);
check!(1.234e13);
check!(2.71828);
check!(1.1e32);
check!(1.1e-32);
check!(2.7182817);
check!(1e-45);
check!(3.4028235e38);
check!(-0.001234);
}
#[test]
fn test_random() {
let n = if cfg!(miri) { 100 } else { 1000000 };
let mut buffer = ryu::Buffer::new();
for _ in 0..n {
let f: f32 = rand::random();
assert_eq!(f, buffer.format_finite(f).parse().unwrap());
}
}
#[test]
#[cfg_attr(miri, ignore)]
fn test_non_finite() {
for i in 0u32..1 << 23 {
let f = f32::from_bits((((1 << 8) - 1) << 23) + i);
assert!(!f.is_finite(), "f={}", f);
ryu::Buffer::new().format_finite(f);
}
}
#[test]
fn test_basic() {
check!(0.0);
check!(-0.0);
check!(1.0);
check!(-1.0);
assert_eq!(pretty(f32::NAN), "NaN");
assert_eq!(pretty(f32::INFINITY), "inf");
assert_eq!(pretty(f32::NEG_INFINITY), "-inf");
}
#[test]
fn test_switch_to_subnormal() {
check!(1.1754944e-38);
}
#[test]
fn test_min_and_max() {
assert_eq!(f32::from_bits(0x7f7fffff), 3.4028235e38);
check!(3.4028235e38);
assert_eq!(f32::from_bits(1), 1e-45);
check!(1e-45);
}
// Check that we return the exact boundary if it is the shortest
// representation, but only if the original floating point number is even.
#[test]
fn test_boundary_round_even() {
check!(33554450.0);
check!(9000000000.0);
check!(34366720000.0);
}
// If the exact value is exactly halfway between two shortest representations,
// then we round to even. It seems like this only makes a difference if the
// last two digits are ...2|5 or ...7|5, and we cut off the 5.
#[test]
fn test_exact_value_round_even() {
check!(305404.12);
check!(8099.0312);
}
#[test]
fn test_lots_of_trailing_zeros() {
// Pattern for the first test: 00111001100000000000000000000000
check!(0.00024414062);
check!(0.0024414062);
check!(0.0043945312);
check!(0.0063476562);
}
#[test]
fn test_regression() {
check!(4.7223665e21);
check!(8388608.0);
check!(16777216.0);
check!(33554436.0);
check!(67131496.0);
check!(1.9310392e-38);
check!(-2.47e-43);
check!(1.993244e-38);
check!(4103.9004);
check!(5339999700.0);
check!(6.0898e-39);
check!(0.0010310042);
check!(2.882326e17);
check!(7.038531e-26);
check!(9.223404e17);
check!(67108870.0);
check!(1e-44);
check!(2.816025e14);
check!(9.223372e18);
check!(1.5846086e29);
check!(1.1811161e19);
check!(5.368709e18);
check!(4.6143166e18);
check!(0.007812537);
check!(1e-45);
check!(1.18697725e20);
check!(1.00014165e-36);
check!(200.0);
check!(33554432.0);
}
#[test]
fn test_looks_like_pow5() {
// These numbers have a mantissa that is the largest power of 5 that fits,
// and an exponent that causes the computation for q to result in 10, which
// is a corner case for Ryƫ.
assert_eq!(f32::from_bits(0x5D1502F9), 6.7108864e17);
check!(6.7108864e17);
assert_eq!(f32::from_bits(0x5D9502F9), 1.3421773e18);
check!(1.3421773e18);
assert_eq!(f32::from_bits(0x5E1502F9), 2.6843546e18);
check!(2.6843546e18);
}
#[test]
fn test_output_length() {
check!(1.0); // already tested in Basic
check!(1.2);
check!(1.23);
check!(1.234);
check!(1.2345);
check!(1.23456);
check!(1.234567);
check!(1.2345678);
check!(1.23456735e-36);
}