| use core::fmt::{self, Write}; |
| |
| #[test] |
| fn test_format_f64() { |
| assert_eq!("1", format!("{:.0}", 1.0f64)); |
| assert_eq!("9", format!("{:.0}", 9.4f64)); |
| assert_eq!("10", format!("{:.0}", 9.9f64)); |
| assert_eq!("9.8", format!("{:.1}", 9.849f64)); |
| assert_eq!("9.9", format!("{:.1}", 9.851f64)); |
| assert_eq!("0", format!("{:.0}", 0.5f64)); |
| assert_eq!("1.23456789e6", format!("{:e}", 1234567.89f64)); |
| assert_eq!("1.23456789e3", format!("{:e}", 1234.56789f64)); |
| assert_eq!("1.23456789E6", format!("{:E}", 1234567.89f64)); |
| assert_eq!("1.23456789E3", format!("{:E}", 1234.56789f64)); |
| assert_eq!("0.0", format!("{:?}", 0.0f64)); |
| assert_eq!("1.01", format!("{:?}", 1.01f64)); |
| |
| let high_cutoff = 1e16_f64; |
| assert_eq!("1e16", format!("{:?}", high_cutoff)); |
| assert_eq!("-1e16", format!("{:?}", -high_cutoff)); |
| assert!(!is_exponential(&format!("{:?}", high_cutoff * (1.0 - 2.0 * f64::EPSILON)))); |
| assert_eq!("-3.0", format!("{:?}", -3f64)); |
| assert_eq!("0.0001", format!("{:?}", 0.0001f64)); |
| assert_eq!("9e-5", format!("{:?}", 0.00009f64)); |
| assert_eq!("1234567.9", format!("{:.1?}", 1234567.89f64)); |
| assert_eq!("1234.6", format!("{:.1?}", 1234.56789f64)); |
| } |
| |
| #[test] |
| fn test_format_f64_rounds_ties_to_even() { |
| assert_eq!("0", format!("{:.0}", 0.5f64)); |
| assert_eq!("2", format!("{:.0}", 1.5f64)); |
| assert_eq!("2", format!("{:.0}", 2.5f64)); |
| assert_eq!("4", format!("{:.0}", 3.5f64)); |
| assert_eq!("4", format!("{:.0}", 4.5f64)); |
| assert_eq!("6", format!("{:.0}", 5.5f64)); |
| assert_eq!("128", format!("{:.0}", 127.5f64)); |
| assert_eq!("128", format!("{:.0}", 128.5f64)); |
| assert_eq!("0.2", format!("{:.1}", 0.25f64)); |
| assert_eq!("0.8", format!("{:.1}", 0.75f64)); |
| assert_eq!("0.12", format!("{:.2}", 0.125f64)); |
| assert_eq!("0.88", format!("{:.2}", 0.875f64)); |
| assert_eq!("0.062", format!("{:.3}", 0.062f64)); |
| assert_eq!("-0", format!("{:.0}", -0.5f64)); |
| assert_eq!("-2", format!("{:.0}", -1.5f64)); |
| assert_eq!("-2", format!("{:.0}", -2.5f64)); |
| assert_eq!("-4", format!("{:.0}", -3.5f64)); |
| assert_eq!("-4", format!("{:.0}", -4.5f64)); |
| assert_eq!("-6", format!("{:.0}", -5.5f64)); |
| assert_eq!("-128", format!("{:.0}", -127.5f64)); |
| assert_eq!("-128", format!("{:.0}", -128.5f64)); |
| assert_eq!("-0.2", format!("{:.1}", -0.25f64)); |
| assert_eq!("-0.8", format!("{:.1}", -0.75f64)); |
| assert_eq!("-0.12", format!("{:.2}", -0.125f64)); |
| assert_eq!("-0.88", format!("{:.2}", -0.875f64)); |
| assert_eq!("-0.062", format!("{:.3}", -0.062f64)); |
| |
| assert_eq!("2e0", format!("{:.0e}", 1.5f64)); |
| assert_eq!("2e0", format!("{:.0e}", 2.5f64)); |
| assert_eq!("4e0", format!("{:.0e}", 3.5f64)); |
| assert_eq!("4e0", format!("{:.0e}", 4.5f64)); |
| assert_eq!("6e0", format!("{:.0e}", 5.5f64)); |
| assert_eq!("1.28e2", format!("{:.2e}", 127.5f64)); |
| assert_eq!("1.28e2", format!("{:.2e}", 128.5f64)); |
| assert_eq!("-2e0", format!("{:.0e}", -1.5f64)); |
| assert_eq!("-2e0", format!("{:.0e}", -2.5f64)); |
| assert_eq!("-4e0", format!("{:.0e}", -3.5f64)); |
| assert_eq!("-4e0", format!("{:.0e}", -4.5f64)); |
| assert_eq!("-6e0", format!("{:.0e}", -5.5f64)); |
| assert_eq!("-1.28e2", format!("{:.2e}", -127.5f64)); |
| assert_eq!("-1.28e2", format!("{:.2e}", -128.5f64)); |
| |
| assert_eq!("2E0", format!("{:.0E}", 1.5f64)); |
| assert_eq!("2E0", format!("{:.0E}", 2.5f64)); |
| assert_eq!("4E0", format!("{:.0E}", 3.5f64)); |
| assert_eq!("4E0", format!("{:.0E}", 4.5f64)); |
| assert_eq!("6E0", format!("{:.0E}", 5.5f64)); |
| assert_eq!("1.28E2", format!("{:.2E}", 127.5f64)); |
| assert_eq!("1.28E2", format!("{:.2E}", 128.5f64)); |
| assert_eq!("-2E0", format!("{:.0E}", -1.5f64)); |
| assert_eq!("-2E0", format!("{:.0E}", -2.5f64)); |
| assert_eq!("-4E0", format!("{:.0E}", -3.5f64)); |
| assert_eq!("-4E0", format!("{:.0E}", -4.5f64)); |
| assert_eq!("-6E0", format!("{:.0E}", -5.5f64)); |
| assert_eq!("-1.28E2", format!("{:.2E}", -127.5f64)); |
| assert_eq!("-1.28E2", format!("{:.2E}", -128.5f64)); |
| } |
| |
| #[test] |
| fn test_format_f32() { |
| assert_eq!("1", format!("{:.0}", 1.0f32)); |
| assert_eq!("9", format!("{:.0}", 9.4f32)); |
| assert_eq!("10", format!("{:.0}", 9.9f32)); |
| assert_eq!("9.8", format!("{:.1}", 9.849f32)); |
| assert_eq!("9.9", format!("{:.1}", 9.851f32)); |
| assert_eq!("0", format!("{:.0}", 0.5f32)); |
| assert_eq!("1.2345679e6", format!("{:e}", 1234567.89f32)); |
| assert_eq!("1.2345679e3", format!("{:e}", 1234.56789f32)); |
| assert_eq!("1.2345679E6", format!("{:E}", 1234567.89f32)); |
| assert_eq!("1.2345679E3", format!("{:E}", 1234.56789f32)); |
| assert_eq!("0.0", format!("{:?}", 0.0f32)); |
| assert_eq!("1.01", format!("{:?}", 1.01f32)); |
| |
| let high_cutoff = 1e16_f32; |
| assert_eq!("1e16", format!("{:?}", high_cutoff)); |
| assert_eq!("-1e16", format!("{:?}", -high_cutoff)); |
| assert!(!is_exponential(&format!("{:?}", high_cutoff * (1.0 - 2.0 * f32::EPSILON)))); |
| assert_eq!("-3.0", format!("{:?}", -3f32)); |
| assert_eq!("0.0001", format!("{:?}", 0.0001f32)); |
| assert_eq!("9e-5", format!("{:?}", 0.00009f32)); |
| assert_eq!("1234567.9", format!("{:.1?}", 1234567.89f32)); |
| assert_eq!("1234.6", format!("{:.1?}", 1234.56789f32)); |
| } |
| |
| #[test] |
| fn test_format_f32_rounds_ties_to_even() { |
| assert_eq!("0", format!("{:.0}", 0.5f32)); |
| assert_eq!("2", format!("{:.0}", 1.5f32)); |
| assert_eq!("2", format!("{:.0}", 2.5f32)); |
| assert_eq!("4", format!("{:.0}", 3.5f32)); |
| assert_eq!("4", format!("{:.0}", 4.5f32)); |
| assert_eq!("6", format!("{:.0}", 5.5f32)); |
| assert_eq!("128", format!("{:.0}", 127.5f32)); |
| assert_eq!("128", format!("{:.0}", 128.5f32)); |
| assert_eq!("0.2", format!("{:.1}", 0.25f32)); |
| assert_eq!("0.8", format!("{:.1}", 0.75f32)); |
| assert_eq!("0.12", format!("{:.2}", 0.125f32)); |
| assert_eq!("0.88", format!("{:.2}", 0.875f32)); |
| assert_eq!("0.062", format!("{:.3}", 0.062f32)); |
| assert_eq!("-0", format!("{:.0}", -0.5f32)); |
| assert_eq!("-2", format!("{:.0}", -1.5f32)); |
| assert_eq!("-2", format!("{:.0}", -2.5f32)); |
| assert_eq!("-4", format!("{:.0}", -3.5f32)); |
| assert_eq!("-4", format!("{:.0}", -4.5f32)); |
| assert_eq!("-6", format!("{:.0}", -5.5f32)); |
| assert_eq!("-128", format!("{:.0}", -127.5f32)); |
| assert_eq!("-128", format!("{:.0}", -128.5f32)); |
| assert_eq!("-0.2", format!("{:.1}", -0.25f32)); |
| assert_eq!("-0.8", format!("{:.1}", -0.75f32)); |
| assert_eq!("-0.12", format!("{:.2}", -0.125f32)); |
| assert_eq!("-0.88", format!("{:.2}", -0.875f32)); |
| assert_eq!("-0.062", format!("{:.3}", -0.062f32)); |
| |
| assert_eq!("2e0", format!("{:.0e}", 1.5f32)); |
| assert_eq!("2e0", format!("{:.0e}", 2.5f32)); |
| assert_eq!("4e0", format!("{:.0e}", 3.5f32)); |
| assert_eq!("4e0", format!("{:.0e}", 4.5f32)); |
| assert_eq!("6e0", format!("{:.0e}", 5.5f32)); |
| assert_eq!("1.28e2", format!("{:.2e}", 127.5f32)); |
| assert_eq!("1.28e2", format!("{:.2e}", 128.5f32)); |
| assert_eq!("-2e0", format!("{:.0e}", -1.5f32)); |
| assert_eq!("-2e0", format!("{:.0e}", -2.5f32)); |
| assert_eq!("-4e0", format!("{:.0e}", -3.5f32)); |
| assert_eq!("-4e0", format!("{:.0e}", -4.5f32)); |
| assert_eq!("-6e0", format!("{:.0e}", -5.5f32)); |
| assert_eq!("-1.28e2", format!("{:.2e}", -127.5f32)); |
| assert_eq!("-1.28e2", format!("{:.2e}", -128.5f32)); |
| |
| assert_eq!("2E0", format!("{:.0E}", 1.5f32)); |
| assert_eq!("2E0", format!("{:.0E}", 2.5f32)); |
| assert_eq!("4E0", format!("{:.0E}", 3.5f32)); |
| assert_eq!("4E0", format!("{:.0E}", 4.5f32)); |
| assert_eq!("6E0", format!("{:.0E}", 5.5f32)); |
| assert_eq!("1.28E2", format!("{:.2E}", 127.5f32)); |
| assert_eq!("1.28E2", format!("{:.2E}", 128.5f32)); |
| assert_eq!("-2E0", format!("{:.0E}", -1.5f32)); |
| assert_eq!("-2E0", format!("{:.0E}", -2.5f32)); |
| assert_eq!("-4E0", format!("{:.0E}", -3.5f32)); |
| assert_eq!("-4E0", format!("{:.0E}", -4.5f32)); |
| assert_eq!("-6E0", format!("{:.0E}", -5.5f32)); |
| assert_eq!("-1.28E2", format!("{:.2E}", -127.5f32)); |
| assert_eq!("-1.28E2", format!("{:.2E}", -128.5f32)); |
| } |
| |
| #[test] |
| fn test_format_f64_max_precision_exponential() { |
| struct ExactExpWriter { |
| prefix: &'static [u8], |
| zeroes_remaining: u32, |
| suffix: &'static [u8], |
| prefix_pos: usize, |
| suffix_pos: usize, |
| total_len: u32, |
| } |
| |
| impl ExactExpWriter { |
| fn new(prefix: &'static str, suffix: &'static str) -> Self { |
| Self { |
| prefix: prefix.as_bytes(), |
| zeroes_remaining: u16::MAX.into(), |
| suffix: suffix.as_bytes(), |
| prefix_pos: 0, |
| suffix_pos: 0, |
| total_len: 0, |
| } |
| } |
| |
| fn finish(self) { |
| assert_eq!(self.prefix_pos, self.prefix.len()); |
| assert_eq!(self.zeroes_remaining, 0); |
| assert_eq!(self.suffix_pos, self.suffix.len()); |
| assert_eq!(self.total_len, u32::from(u16::MAX) + 4); |
| } |
| } |
| |
| impl Write for ExactExpWriter { |
| fn write_str(&mut self, s: &str) -> fmt::Result { |
| for byte in s.bytes() { |
| self.total_len += 1; |
| |
| if self.prefix_pos < self.prefix.len() { |
| assert_eq!(byte, self.prefix[self.prefix_pos]); |
| self.prefix_pos += 1; |
| } else if self.zeroes_remaining > 0 { |
| assert_eq!(byte, b'0'); |
| self.zeroes_remaining -= 1; |
| } else { |
| assert!(self.suffix_pos < self.suffix.len()); |
| assert_eq!(byte, self.suffix[self.suffix_pos]); |
| self.suffix_pos += 1; |
| } |
| } |
| |
| Ok(()) |
| } |
| } |
| |
| fn assert_exact_exp(args: fmt::Arguments<'_>, prefix: &'static str, suffix: &'static str) { |
| let mut writer = ExactExpWriter::new(prefix, suffix); |
| fmt::write(&mut writer, args).unwrap(); |
| writer.finish(); |
| } |
| |
| assert_exact_exp(format_args!("{:.65535e}", 0.0f64), "0.", "e0"); |
| assert_exact_exp(format_args!("{:.65535e}", 1.0f64), "1.", "e0"); |
| assert_exact_exp(format_args!("{:.65535E}", 0.0f64), "0.", "E0"); |
| assert_exact_exp(format_args!("{:.65535E}", 1.0f64), "1.", "E0"); |
| assert_exact_exp(format_args!("{:65535.65535e}", 1.0f64), "1.", "e0"); |
| } |
| |
| fn is_exponential(s: &str) -> bool { |
| s.contains("e") || s.contains("E") |
| } |
