mod builders; mod float; mod num; #[test] fn test_lifetime() { // Trigger all different forms of expansion, // and check that each of them can be stored as a variable. let a = format_args!("hello"); let a = format_args!("hello {a}"); let a = format_args!("hello {a:1}"); let a = format_args!("hello {a} {a:?}"); assert_eq!(a.to_string(), "hello hello hello hello hello hello hello"); // Check that temporaries as arguments are extended. let b = format_args!("{}", String::new()); let c = format_args!("{}{}", String::new(), String::new()); assert_eq!(b.to_string(), ""); assert_eq!(c.to_string(), ""); // Without arguments, it should also work in consts. const A: std::fmt::Arguments<'static> = format_args!("hello"); assert_eq!(A.to_string(), "hello"); } #[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 *const _)); assert_eq!(format!("{b:p}"), format!("{:p}", b as *const _)); } #[test] fn test_fmt_debug_of_raw_pointers() { use core::fmt::Debug; use core::ptr; fn check_fmt(t: T, start: &str, contains: &str) { let formatted = format!("{:?}", t); assert!(formatted.starts_with(start), "{formatted:?} doesn't start with {start:?}"); assert!(formatted.contains(contains), "{formatted:?} doesn't contain {contains:?}"); } assert_eq!(format!("{:?}", ptr::without_provenance_mut::(0x100)), "0x100"); assert_eq!(format!("{:?}", ptr::without_provenance::(0x100)), "0x100"); let slice = ptr::slice_from_raw_parts(ptr::without_provenance::(0x100), 3); assert_eq!(format!("{:?}", slice as *mut [i32]), "Pointer { addr: 0x100, metadata: 3 }"); assert_eq!(format!("{:?}", slice as *const [i32]), "Pointer { addr: 0x100, metadata: 3 }"); let vtable = &mut 500 as &mut dyn Debug; check_fmt(vtable as *mut dyn Debug, "Pointer { addr: ", ", metadata: DynMetadata("); check_fmt(vtable as *const dyn Debug, "Pointer { addr: ", ", metadata: DynMetadata("); } #[test] fn test_fmt_debug_of_mut_reference() { let mut x: u32 = 0; assert_eq!(format!("{:?}", &mut x), "0"); } #[test] fn test_default_write_impls() { use core::fmt::Write; struct Buf(String); impl Write for Buf { fn write_str(&mut self, s: &str) -> core::fmt::Result { self.0.write_str(s) } } let mut buf = Buf(String::new()); buf.write_char('a').unwrap(); assert_eq!(buf.0, "a"); let mut buf = Buf(String::new()); buf.write_fmt(format_args!("a")).unwrap(); assert_eq!(buf.0, "a"); } #[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 "); } #[test] fn test_maybe_uninit_short() { // Ensure that the trimmed `MaybeUninit` Debug implementation doesn't break let x = core::mem::MaybeUninit::new(0u32); assert_eq!(format!("{x:?}"), "MaybeUninit"); } #[test] fn formatting_options_ctor() { use core::fmt::FormattingOptions; assert_eq!(FormattingOptions::new(), FormattingOptions::default()); } #[test] #[allow(deprecated)] fn formatting_options_flags() { use core::fmt::*; for sign in [None, Some(Sign::Plus), Some(Sign::Minus)] { for alternate in [true, false] { for sign_aware_zero_pad in [true, false] { for debug_as_hex in [None, Some(DebugAsHex::Lower), Some(DebugAsHex::Upper)] { let mut formatting_options = FormattingOptions::new(); formatting_options .sign(sign) .sign_aware_zero_pad(sign_aware_zero_pad) .alternate(alternate) .debug_as_hex(debug_as_hex); assert_eq!(formatting_options.get_sign(), sign); assert_eq!(formatting_options.get_alternate(), alternate); assert_eq!(formatting_options.get_sign_aware_zero_pad(), sign_aware_zero_pad); assert_eq!(formatting_options.get_debug_as_hex(), debug_as_hex); let mut output = String::new(); let fmt = Formatter::new(&mut output, formatting_options); assert_eq!(fmt.options(), formatting_options); assert_eq!(fmt.sign_minus(), sign == Some(Sign::Minus)); assert_eq!(fmt.sign_plus(), sign == Some(Sign::Plus)); assert_eq!(fmt.alternate(), alternate); assert_eq!(fmt.sign_aware_zero_pad(), sign_aware_zero_pad); // The flags method is deprecated. // This checks compatibility with older versions of Rust. assert_eq!(fmt.flags() & 1 != 0, sign == Some(Sign::Plus)); assert_eq!(fmt.flags() & 2 != 0, sign == Some(Sign::Minus)); assert_eq!(fmt.flags() & 4 != 0, alternate); assert_eq!(fmt.flags() & 8 != 0, sign_aware_zero_pad); assert_eq!(fmt.flags() & 16 != 0, debug_as_hex == Some(DebugAsHex::Lower)); assert_eq!(fmt.flags() & 32 != 0, debug_as_hex == Some(DebugAsHex::Upper)); assert_eq!(fmt.flags() & 0xFFFF_FFC0, 0); } } } } }