Import 'ryu' crate version 1.0.5
Bug: 163175424
Test: N/A
Change-Id: I7bda5411adccb26198c53ed1cb41fc6bb08468d7
diff --git a/tests/f2s_test.rs b/tests/f2s_test.rs
new file mode 100644
index 0000000..916250e
--- /dev/null
+++ b/tests/f2s_test.rs
@@ -0,0 +1,172 @@
+// 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
+// http://www.apache.org/licenses/LICENSE-2.0)
+//
+// 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
+// https://www.boost.org/LICENSE_1_0.txt)
+//
+// 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.
+
+#[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 Ryū.
+ 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);
+}