assertables/assert_f64/assert_f64_eq.rs
1//! Assert a floating point 64-bit number is equal to another within f64::EPSILON.
2//!
3//! Pseudocode:<br>
4//! a = b
5//!
6//! # Example
7//!
8//! ```rust
9//! use assertables::*;
10//!
11//! let a: f64 = 1.0 / 3.0;
12//! let b: f64 = 0.3333333333333334;
13//! assert_f64_eq!(a, b);
14//! ```
15//!
16//! # Module macros
17//!
18//! * [`assert_f64_eq`](macro@crate::assert_f64_eq)
19//! * [`assert_f64_eq_as_result`](macro@crate::assert_f64_eq_as_result)
20//! * [`debug_assert_f64_eq`](macro@crate::debug_assert_f64_eq)
21
22/// Assert two floating point numbers are equal within f64::EPSILON.
23///
24/// Pseudocode:<br>
25/// a = b
26///
27/// * If true, return Result `Ok(())`.
28///
29/// * Otherwise, return Result `Err(message)`.
30///
31/// This macro is useful for runtime checks, such as checking parameters,
32/// or sanitizing inputs, or handling different results in different ways.
33///
34/// # Module macros
35///
36/// * [`assert_f64_eq`](macro@crate::assert_f64_eq)
37/// * [`assert_f64_eq_as_result`](macro@crate::assert_f64_eq_as_result)
38/// * [`debug_assert_f64_eq`](macro@crate::debug_assert_f64_eq)
39///
40#[macro_export]
41macro_rules! assert_f64_eq_as_result {
42 ($a:expr, $b:expr $(,)?) => {
43 match (&$a, &$b) {
44 (a, b) => {
45 if (a >= b && a - b < f64::EPSILON) || (a <= b && b - a < f64::EPSILON) {
46 Ok(())
47 } else {
48 Err(format!(
49 concat!(
50 "assertion failed: `assert_f64_eq!(a, b)`\n",
51 "https://docs.rs/assertables/9.8.3/assertables/macro.assert_f64_eq.html\n",
52 " a label: `{}`,\n",
53 " a debug: `{}`,\n",
54 " b label: `{}`,\n",
55 " b debug: `{:?}`,\n",
56 " diff: `{}`,\n",
57 " ε: `{}`",
58 ),
59 stringify!($a),
60 a,
61 stringify!($b),
62 b,
63 a - b,
64 f64::EPSILON,
65 ))
66 }
67 }
68 }
69 };
70}
71
72#[cfg(test)]
73mod test_assert_f64_eq_as_result {
74 use crate::assert_f64::{EQ, EQ_GT, EQ_LT, GT, LT};
75 use std::sync::Once;
76
77 #[test]
78 fn eq() {
79 let a: f64 = EQ;
80 let b: f64 = EQ;
81 for _ in 0..1 {
82 let actual = assert_f64_eq_as_result!(a, b);
83 assert_eq!(actual.unwrap(), ());
84 }
85 }
86
87 #[test]
88 fn eq_once() {
89 static A: Once = Once::new();
90 fn a() -> f64 {
91 if A.is_completed() {
92 panic!("A.is_completed()")
93 } else {
94 A.call_once(|| {})
95 }
96 EQ
97 }
98
99 static B: Once = Once::new();
100 fn b() -> f64 {
101 if B.is_completed() {
102 panic!("B.is_completed()")
103 } else {
104 B.call_once(|| {})
105 }
106 EQ
107 }
108
109 assert_eq!(A.is_completed(), false);
110 assert_eq!(B.is_completed(), false);
111 let result = assert_f64_eq_as_result!(a(), b());
112 assert!(result.is_ok());
113 assert_eq!(A.is_completed(), true);
114 assert_eq!(B.is_completed(), true);
115 }
116
117 #[test]
118 fn eq_lt() {
119 let a: f64 = EQ;
120 let b: f64 = EQ_GT;
121 for _ in 0..1 {
122 let actual = assert_f64_eq_as_result!(a, b);
123 assert_eq!(actual.unwrap(), ());
124 }
125 }
126
127 #[test]
128 fn eq_lt_once() {
129 static A: Once = Once::new();
130 fn a() -> f64 {
131 if A.is_completed() {
132 panic!("A.is_completed()")
133 } else {
134 A.call_once(|| {})
135 }
136 EQ
137 }
138
139 static B: Once = Once::new();
140 fn b() -> f64 {
141 if B.is_completed() {
142 panic!("B.is_completed()")
143 } else {
144 B.call_once(|| {})
145 }
146 EQ_GT
147 }
148
149 assert_eq!(A.is_completed(), false);
150 assert_eq!(B.is_completed(), false);
151 let result = assert_f64_eq_as_result!(a(), b());
152 assert!(result.is_ok());
153 assert_eq!(A.is_completed(), true);
154 assert_eq!(B.is_completed(), true);
155 }
156
157 #[test]
158 fn eq_gt() {
159 let a: f64 = EQ;
160 let b: f64 = EQ_LT;
161 for _ in 0..1 {
162 let actual = assert_f64_eq_as_result!(a, b);
163 assert_eq!(actual.unwrap(), ());
164 }
165 }
166
167 #[test]
168 fn eq_gt_once() {
169 static A: Once = Once::new();
170 fn a() -> f64 {
171 if A.is_completed() {
172 panic!("A.is_completed()")
173 } else {
174 A.call_once(|| {})
175 }
176 EQ
177 }
178
179 static B: Once = Once::new();
180 fn b() -> f64 {
181 if B.is_completed() {
182 panic!("B.is_completed()")
183 } else {
184 B.call_once(|| {})
185 }
186 EQ_LT
187 }
188
189 assert_eq!(A.is_completed(), false);
190 assert_eq!(B.is_completed(), false);
191 let result = assert_f64_eq_as_result!(a(), b());
192 assert!(result.is_ok());
193 assert_eq!(A.is_completed(), true);
194 assert_eq!(B.is_completed(), true);
195 }
196
197 #[test]
198 fn lt() {
199 let a: f64 = EQ;
200 let b: f64 = GT;
201 let actual = assert_f64_eq_as_result!(a, b);
202 let message = concat!(
203 "assertion failed: `assert_f64_eq!(a, b)`\n",
204 "https://docs.rs/assertables/9.8.3/assertables/macro.assert_f64_eq.html\n",
205 " a label: `a`,\n",
206 " a debug: `0.3333333333333333`,\n",
207 " b label: `b`,\n",
208 " b debug: `0.3333333333333339`,\n",
209 " diff: `-0.0000000000000006106226635438361`,\n",
210 " ε: `0.0000000000000002220446049250313`",
211 );
212 assert_eq!(actual.unwrap_err(), message);
213 }
214
215 #[test]
216 fn gt() {
217 let a: f64 = EQ;
218 let b: f64 = LT;
219 let actual = assert_f64_eq_as_result!(a, b);
220 let message = concat!(
221 "assertion failed: `assert_f64_eq!(a, b)`\n",
222 "https://docs.rs/assertables/9.8.3/assertables/macro.assert_f64_eq.html\n",
223 " a label: `a`,\n",
224 " a debug: `0.3333333333333333`,\n",
225 " b label: `b`,\n",
226 " b debug: `0.3333333333333329`,\n",
227 " diff: `0.0000000000000003885780586188048`,\n",
228 " ε: `0.0000000000000002220446049250313`",
229 );
230 assert_eq!(actual.unwrap_err(), message);
231 }
232}
233
234/// Assert a floating point 64-bit number is equal to another within f64::EPSILON.
235///
236/// Pseudocode:<br>
237/// a = b
238///
239/// * If true, return `()`.
240///
241/// * Otherwise, call [`panic!`] with a message and the values of the
242/// expressions with their debug representations.
243///
244/// # Examples
245///
246/// ```rust
247/// use assertables::*;
248/// # use std::panic;
249///
250/// # fn main() {
251/// let a: f64 = 1.0 / 3.0;
252/// let b: f64 = 0.3333333333333335;
253/// assert_f64_eq!(a, b);
254///
255/// # let result = panic::catch_unwind(|| {
256/// // This will panic
257/// let a: f64 = 1.0 / 3.0;
258/// let b: f64 = 0.3333333333333339;
259/// assert_f64_eq!(a, b);
260/// # });
261/// // assertion failed: `assert_f64_eq!(a, b)`
262/// // https://docs.rs/assertables/…/assertables/macro.assert_f64_eq.html
263/// // a label: `a`,
264/// // a debug: `0.3333333333333333`,
265/// // b label: `b`,
266/// // b debug: `0.3333333333333339`,`
267/// // diff: `-0.0000000000000006106226635438361`,
268/// // ε: `0.0000000000000002220446049250313`
269/// # let actual = result.unwrap_err().downcast::<String>().unwrap().to_string();
270/// # let message = concat!(
271/// # "assertion failed: `assert_f64_eq!(a, b)`\n",
272/// # "https://docs.rs/assertables/9.8.3/assertables/macro.assert_f64_eq.html\n",
273/// # " a label: `a`,\n",
274/// # " a debug: `0.3333333333333333`,\n",
275/// # " b label: `b`,\n",
276/// # " b debug: `0.3333333333333339`,\n",
277/// # " diff: `-0.0000000000000006106226635438361`,\n",
278/// # " ε: `0.0000000000000002220446049250313`",
279/// # );
280/// # assert_eq!(actual, message);
281/// # }
282/// ```
283///
284/// # Module macros
285///
286/// * [`assert_f64_eq`](macro@crate::assert_f64_eq)
287/// * [`assert_f64_eq_as_result`](macro@crate::assert_f64_eq_as_result)
288/// * [`debug_assert_f64_eq`](macro@crate::debug_assert_f64_eq)
289///
290#[macro_export]
291macro_rules! assert_f64_eq {
292 ($a:expr, $b:expr $(,)?) => {
293 match $crate::assert_f64_eq_as_result!($a, $b) {
294 Ok(()) => (),
295 Err(err) => panic!("{}", err),
296 }
297 };
298 ($a:expr, $b:expr, $($message:tt)+) => {
299 match $crate::assert_f64_eq_as_result!($a, $b) {
300 Ok(()) => (),
301 Err(err) => panic!("{}\n{}", format_args!($($message)+), err),
302 }
303 };
304}
305
306#[cfg(test)]
307mod test_assert_f64_eq {
308 use crate::assert_f64::EQ;
309 use std::panic;
310
311 #[test]
312 fn eq() {
313 let a: f64 = EQ;
314 let b: f64 = EQ;
315 for _ in 0..1 {
316 let actual = assert_f64_eq!(a, b);
317 assert_eq!(actual, ());
318 }
319 }
320}
321
322/// Assert a floating point 64-bit number is equal to another within f64::EPSILON.
323///
324/// Pseudocode:<br>
325/// a = b
326///
327/// This macro provides the same statements as [`assert_f64_eq`](macro.assert_f64_eq.html),
328/// except this macro's statements are only enabled in non-optimized
329/// builds by default. An optimized build will not execute this macro's
330/// statements unless `-C debug-assertions` is passed to the compiler.
331///
332/// This macro is useful for checks that are too expensive to be present
333/// in a release build but may be helpful during development.
334///
335/// The result of expanding this macro is always type checked.
336///
337/// An unchecked assertion allows a program in an inconsistent state to
338/// keep running, which might have unexpected consequences but does not
339/// introduce unsafety as long as this only happens in safe code. The
340/// performance cost of assertions, however, is not measurable in general.
341/// Replacing `assert*!` with `debug_assert*!` is thus only encouraged
342/// after thorough profiling, and more importantly, only in safe code!
343///
344/// This macro is intended to work in a similar way to
345/// [`::std::debug_assert`](https://doc.rust-lang.org/std/macro.debug_assert.html).
346///
347/// # Module macros
348///
349/// * [`assert_f64_eq`](macro@crate::assert_f64_eq)
350/// * [`assert_f64_eq`](macro@crate::assert_f64_eq)
351/// * [`debug_assert_f64_eq`](macro@crate::debug_assert_f64_eq)
352///
353#[macro_export]
354macro_rules! debug_assert_f64_eq {
355 ($($arg:tt)*) => {
356 if $crate::cfg!(debug_assertions) {
357 $crate::assert_f64_eq!($($arg)*);
358 }
359 };
360}