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7d1de7f994
Rather than writing character at a time, optimise Debug implementation for core::ascii::Char such that it writes the entire representation as with a single write_str call. With that, add tests for Display and Debug implementations.
29 lines
932 B
Rust
29 lines
932 B
Rust
use core::ascii::Char;
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use core::fmt::Write;
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/// Tests Display implementation for ascii::Char.
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#[test]
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fn test_display() {
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let want = (0..128u8).map(|b| b as char).collect::<String>();
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let mut got = String::with_capacity(128);
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for byte in 0..128 {
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write!(&mut got, "{}", Char::from_u8(byte).unwrap()).unwrap();
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}
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assert_eq!(want, got);
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}
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/// Tests Debug implementation for ascii::Char.
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#[test]
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fn test_debug_control() {
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for byte in 0..128u8 {
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let mut want = format!("{:?}", byte as char);
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// `char` uses `'\u{#}'` representation where ascii::char uses `'\x##'`.
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// Transform former into the latter.
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if let Some(rest) = want.strip_prefix("'\\u{") {
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want = format!("'\\x{:0>2}'", rest.strip_suffix("}'").unwrap());
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}
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let chr = core::ascii::Char::from_u8(byte).unwrap();
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assert_eq!(want, format!("{chr:?}"), "byte: {byte}");
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}
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}
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