rust/library/core/tests/fmt/mod.rs

46 lines
1.3 KiB
Rust

mod builders;
mod float;
mod num;
#[test]
fn test_format_flags() {
// No residual flags left by pointer formatting
let p = "".as_ptr();
assert_eq!(format!("{:p} {:x}", p, 16), format!("{p:p} 10"));
assert_eq!(format!("{: >3}", 'a'), " a");
}
#[test]
fn test_pointer_formats_data_pointer() {
let b: &[u8] = b"";
let s: &str = "";
assert_eq!(format!("{s:p}"), format!("{:p}", s.as_ptr()));
assert_eq!(format!("{b:p}"), format!("{:p}", b.as_ptr()));
}
#[test]
fn test_estimated_capacity() {
assert_eq!(format_args!("").estimated_capacity(), 0);
assert_eq!(format_args!("{}", { "" }).estimated_capacity(), 0);
assert_eq!(format_args!("Hello").estimated_capacity(), 5);
assert_eq!(format_args!("Hello, {}!", { "" }).estimated_capacity(), 16);
assert_eq!(format_args!("{}, hello!", { "World" }).estimated_capacity(), 0);
assert_eq!(format_args!("{}. 16-bytes piece", { "World" }).estimated_capacity(), 32);
}
#[test]
fn pad_integral_resets() {
struct Bar;
impl core::fmt::Display for Bar {
fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
"1".fmt(f)?;
f.pad_integral(true, "", "5")?;
"1".fmt(f)
}
}
assert_eq!(format!("{Bar:<03}"), "1 0051 ");
}