assertables/assert_abs_diff/
assert_abs_diff_gt_x.rs

1//! Assert an absolute difference is greater than an expression.
2//!
3//! Pseudocode:<br>
4//! |Δ| > x
5//!
6//! # Example
7//!
8//! ```rust
9//! use assertables::*;
10//!
11//! let a = 10;
12//! let b = 13;
13//! let x = 2;
14//! assert_abs_diff_gt_x!(a, b, x);
15//! ```
16//!
17//! # Module macros
18//!
19//! * [`assert_abs_diff_gt_x`](macro@crate::assert_abs_diff_gt_x)
20//! * [`assert_abs_diff_gt_x_as_result`](macro@crate::assert_abs_diff_gt_x_as_result)
21//! * [`debug_assert_abs_diff_gt_x`](macro@crate::debug_assert_abs_diff_gt_x)
22
23/// Assert an absolute difference is greater than an expression.
24///
25/// Pseudocode:<br>
26/// |Δ| > x
27///
28/// * If true, return `Ok((lhs, rhs))`.
29///
30/// * Otherwise, return [`Err`] with a message and the values of the
31///   expressions with their debug representations.
32///
33/// This macro is useful for runtime checks, such as checking parameters,
34/// or sanitizing inputs, or handling different results in different ways.
35///
36/// # Module macros
37///
38/// * [`assert_abs_diff_gt_x`](macro@crate::assert_abs_diff_gt_x)
39/// * [`assert_abs_diff_gt_x_as_result`](macro@crate::assert_abs_diff_gt_x_as_result)
40/// * [`debug_assert_abs_diff_gt_x`](macro@crate::debug_assert_abs_diff_gt_x)
41///
42#[macro_export]
43macro_rules! assert_abs_diff_gt_x_as_result {
44    ($a:expr, $b:expr, $x:expr $(,)?) => {
45        match (&$a, &$b, &$x) {
46            (a, b, x) => {
47                match ::std::panic::catch_unwind(|| if (a >= b) { a - b } else { b - a }) {
48                    Ok(abs_diff) => {
49                        if abs_diff > *x {
50                            Ok((abs_diff, *x))
51                        } else {
52                            Err(
53                                format!(
54                                    concat!(
55                                        "assertion failed: `assert_abs_diff_gt_x!(a, b, x)`\n",
56                                        "https://docs.rs/assertables/9.6.1/assertables/macro.assert_abs_diff_gt_x.html\n",
57                                        " a label: `{}`,\n",
58                                        " a debug: `{:?}`,\n",
59                                        " b label: `{}`,\n",
60                                        " b debug: `{:?}`,\n",
61                                        " x label: `{}`,\n",
62                                        " x debug: `{:?}`,\n",
63                                        "     |Δ|: `{:?}`,\n",
64                                        " |Δ| > x: {}"
65                                    ),
66                                    stringify!($a),
67                                    a,
68                                    stringify!($b),
69                                    b,
70                                    stringify!($x),
71                                    x,
72                                    abs_diff,
73                                    false
74                                )
75                            )
76                        }
77                    },
78                    Err(_err) => {
79                        Err(
80                            format!(
81                                concat!(
82                                    "assertion failed: `assert_abs_diff_gt_x!(a, b, x)`\n",
83                                    "https://docs.rs/assertables/9.6.1/assertables/macro.assert_abs_diff_gt_x.html\n",
84                                    " a label: `{}`,\n",
85                                    " a debug: `{:?}`,\n",
86                                    " b label: `{}`,\n",
87                                    " b debug: `{:?}`,\n",
88                                    " x label: `{}`,\n",
89                                    " x debug: `{:?}`,\n",
90                                    "     |Δ|: panic", //TODO add the panic message
91                                ),
92                                stringify!($a),
93                                a,
94                                stringify!($b),
95                                b,
96                                stringify!($x),
97                                x
98                            )
99                        )
100                    }
101                }
102            }
103        }
104    };
105}
106
107#[cfg(test)]
108mod test_assert_abs_diff_gt_x_as_result {
109    use std::sync::Once;
110
111    #[test]
112    fn gt() {
113        let a: i8 = 10;
114        let b: i8 = 13;
115        let x: i8 = 2;
116        for _ in 0..1 {
117            let actual = assert_abs_diff_gt_x_as_result!(a, b, x);
118            assert_eq!(actual.unwrap(), (3, 2));
119        }
120    }
121
122    #[test]
123    fn gt_once() {
124        static A: Once = Once::new();
125        fn a() -> i8 {
126            if A.is_completed() {
127                panic!("A.is_completed()")
128            } else {
129                A.call_once(|| {})
130            }
131            10
132        }
133
134        static B: Once = Once::new();
135        fn b() -> i8 {
136            if B.is_completed() {
137                panic!("B.is_completed()")
138            } else {
139                B.call_once(|| {})
140            }
141            13
142        }
143
144        static X: Once = Once::new();
145        fn x() -> i8 {
146            if X.is_completed() {
147                panic!("X.is_completed()")
148            } else {
149                X.call_once(|| {})
150            }
151            2
152        }
153
154        assert_eq!(A.is_completed(), false);
155        assert_eq!(B.is_completed(), false);
156        assert_eq!(X.is_completed(), false);
157        let result = assert_abs_diff_gt_x_as_result!(a(), b(), x());
158        assert!(result.is_ok());
159        assert_eq!(A.is_completed(), true);
160        assert_eq!(B.is_completed(), true);
161        assert_eq!(X.is_completed(), true);
162    }
163
164    #[test]
165    fn eq() {
166        let a: i8 = 10;
167        let b: i8 = 13;
168        let x: i8 = 3;
169        let actual = assert_abs_diff_gt_x_as_result!(a, b, x);
170        let message = concat!(
171            "assertion failed: `assert_abs_diff_gt_x!(a, b, x)`\n",
172            "https://docs.rs/assertables/9.6.1/assertables/macro.assert_abs_diff_gt_x.html\n",
173            " a label: `a`,\n",
174            " a debug: `10`,\n",
175            " b label: `b`,\n",
176            " b debug: `13`,\n",
177            " x label: `x`,\n",
178            " x debug: `3`,\n",
179            "     |Δ|: `3`,\n",
180            " |Δ| > x: false"
181        );
182        assert_eq!(actual.unwrap_err(), message);
183    }
184
185    #[test]
186    fn lt() {
187        let a: i8 = 10;
188        let b: i8 = 13;
189        let x: i8 = 4;
190        let actual = assert_abs_diff_gt_x_as_result!(a, b, x);
191        let message = concat!(
192            "assertion failed: `assert_abs_diff_gt_x!(a, b, x)`\n",
193            "https://docs.rs/assertables/9.6.1/assertables/macro.assert_abs_diff_gt_x.html\n",
194            " a label: `a`,\n",
195            " a debug: `10`,\n",
196            " b label: `b`,\n",
197            " b debug: `13`,\n",
198            " x label: `x`,\n",
199            " x debug: `4`,\n",
200            "     |Δ|: `3`,\n",
201            " |Δ| > x: false"
202        );
203        assert_eq!(actual.unwrap_err(), message);
204    }
205
206    #[test]
207    fn overflow() {
208        let a: i8 = i8::MAX;
209        let b: i8 = i8::MIN;
210        let x: i8 = 0;
211        let actual = assert_abs_diff_gt_x_as_result!(a, b, x);
212        let message = format!(
213            concat!(
214                "assertion failed: `assert_abs_diff_gt_x!(a, b, x)`\n",
215                "https://docs.rs/assertables/9.6.1/assertables/macro.assert_abs_diff_gt_x.html\n",
216                " a label: `a`,\n",
217                " a debug: `{}`,\n",
218                " b label: `b`,\n",
219                " b debug: `{}`,\n",
220                " x label: `x`,\n",
221                " x debug: `{}`,\n",
222                "     |Δ|: panic"
223            ),
224            a, b, x
225        );
226        assert_eq!(actual.unwrap_err(), message);
227    }
228}
229
230/// Assert an absolute difference is greater than an expression.
231///
232/// Pseudocode:<br>
233/// |Δ| > x
234///
235/// * If true, return `(lhs, rhs)`.
236///
237/// * Otherwise, call [`panic!`] with a message and the values of the
238///   expressions with their debug representations.
239///
240/// # Examples
241///
242/// ```rust
243/// use assertables::*;
244/// # use std::panic;
245///
246/// # fn main() {
247/// let a = 10;
248/// let b = 13;
249/// let x = 2;
250/// assert_abs_diff_gt_x!(a, b, x);
251///
252/// # let result = panic::catch_unwind(|| {
253/// // This will panic
254/// let a = 10;
255/// let b = 13;
256/// let x = 4;
257/// assert_abs_diff_gt_x!(a, b, x);
258/// # });
259/// // assertion failed: `assert_abs_diff_gt_x!(a, b)`
260/// // https://docs.rs/assertables/9.6.1/assertables/macro.assert_abs_diff_gt_x.html
261/// //  a label: `a`,
262/// //  a debug: `10`,
263/// //  b label: `b`,
264/// //  b debug: `13`,
265/// //  x label: `x`,
266/// //  x debug: `4`,
267/// //      |Δ|: `3`,
268/// //  |Δ| > x: false
269/// # let actual = result.unwrap_err().downcast::<String>().unwrap().to_string();
270/// # let message = concat!(
271/// #     "assertion failed: `assert_abs_diff_gt_x!(a, b, x)`\n",
272/// #     "https://docs.rs/assertables/9.6.1/assertables/macro.assert_abs_diff_gt_x.html\n",
273/// #     " a label: `a`,\n",
274/// #     " a debug: `10`,\n",
275/// #     " b label: `b`,\n",
276/// #     " b debug: `13`,\n",
277/// #     " x label: `x`,\n",
278/// #     " x debug: `4`,\n",
279/// #     "     |Δ|: `3`,\n",
280/// #     " |Δ| > x: false"
281/// # );
282/// # assert_eq!(actual, message);
283/// # }
284/// ```
285///
286/// # Module macros
287///
288/// * [`assert_abs_diff_gt_x`](macro@crate::assert_abs_diff_gt_x)
289/// * [`assert_abs_diff_gt_x_as_result`](macro@crate::assert_abs_diff_gt_x_as_result)
290/// * [`debug_assert_abs_diff_gt_x`](macro@crate::debug_assert_abs_diff_gt_x)
291///
292#[macro_export]
293macro_rules! assert_abs_diff_gt_x {
294    ($a:expr, $b:expr, $x:expr $(,)?) => {
295        match $crate::assert_abs_diff_gt_x_as_result!($a, $b, $x) {
296            Ok(x) => x,
297            Err(err) => panic!("{}", err),
298        }
299    };
300    ($a:expr, $b:expr, $x:expr, $($message:tt)+) => {
301        match $crate::assert_abs_diff_gt_x_as_result!($a, $b, $x) {
302            Ok(x) => x,
303            Err(err) => panic!("{}\n{}", format_args!($($message)+), err),
304        }
305    };
306}
307
308#[cfg(test)]
309mod assert_abs_diff_gt_x {
310    use std::panic;
311
312    #[test]
313    fn gt() {
314        let a = 10;
315        let b = 13;
316        let x = 2;
317        for _ in 0..1 {
318            let actual = assert_abs_diff_gt_x!(a, b, x);
319            assert_eq!(actual, (3, 2));
320        }
321    }
322
323    #[test]
324    fn eq() {
325        let result = panic::catch_unwind(|| {
326            let a = 10;
327            let b = 13;
328            let x = 3;
329            let _actual = assert_abs_diff_gt_x!(a, b, x);
330        });
331        let message = concat!(
332            "assertion failed: `assert_abs_diff_gt_x!(a, b, x)`\n",
333            "https://docs.rs/assertables/9.6.1/assertables/macro.assert_abs_diff_gt_x.html\n",
334            " a label: `a`,\n",
335            " a debug: `10`,\n",
336            " b label: `b`,\n",
337            " b debug: `13`,\n",
338            " x label: `x`,\n",
339            " x debug: `3`,\n",
340            "     |Δ|: `3`,\n",
341            " |Δ| > x: false"
342        );
343        assert_eq!(
344            result
345                .unwrap_err()
346                .downcast::<String>()
347                .unwrap()
348                .to_string(),
349            message
350        );
351    }
352
353    #[test]
354    fn lt() {
355        let result = panic::catch_unwind(|| {
356            let a = 10;
357            let b = 13;
358            let x = 4;
359            let _actual = assert_abs_diff_gt_x!(a, b, x);
360        });
361        let message = concat!(
362            "assertion failed: `assert_abs_diff_gt_x!(a, b, x)`\n",
363            "https://docs.rs/assertables/9.6.1/assertables/macro.assert_abs_diff_gt_x.html\n",
364            " a label: `a`,\n",
365            " a debug: `10`,\n",
366            " b label: `b`,\n",
367            " b debug: `13`,\n",
368            " x label: `x`,\n",
369            " x debug: `4`,\n",
370            "     |Δ|: `3`,\n",
371            " |Δ| > x: false"
372        );
373        assert_eq!(
374            result
375                .unwrap_err()
376                .downcast::<String>()
377                .unwrap()
378                .to_string(),
379            message
380        );
381    }
382
383    #[test]
384    fn overflow() {
385        let a: i8 = i8::MAX;
386        let b: i8 = i8::MIN;
387        let x: i8 = 0;
388        let result = panic::catch_unwind(|| {
389            let _actual = assert_abs_diff_gt_x!(a, b, x);
390        });
391        let message = format!(
392            concat!(
393                "assertion failed: `assert_abs_diff_gt_x!(a, b, x)`\n",
394                "https://docs.rs/assertables/9.6.1/assertables/macro.assert_abs_diff_gt_x.html\n",
395                " a label: `a`,\n",
396                " a debug: `{}`,\n",
397                " b label: `b`,\n",
398                " b debug: `{}`,\n",
399                " x label: `x`,\n",
400                " x debug: `{}`,\n",
401                "     |Δ|: panic"
402            ),
403            a, b, x
404        );
405        assert_eq!(
406            result
407                .unwrap_err()
408                .downcast::<String>()
409                .unwrap()
410                .to_string(),
411            message
412        );
413    }
414}
415
416/// Assert an absolute difference is greater than an expression.
417///
418/// Pseudocode:<br>
419/// |Δ| > c
420///
421/// This macro provides the same statements as [`assert_abs_diff_gt_x`](macro.assert_abs_diff_gt_x.html),
422/// except this macro's statements are only enabled in non-optimized
423/// builds by default. An optimized build will not execute this macro's
424/// statements unless `-x debug-assertions` is passed to the compiler.
425///
426/// This macro is useful for checks that are too expensive to be present
427/// in a release build but may be helpful during development.
428///
429/// The result of expanding this macro is always type checked.
430///
431/// An unchecked assertion allows a program in an inconsistent state to
432/// keep running, which might have unexpected consequences but does not
433/// introduce unsafety as long as this only happens in safe code. The
434/// performance cost of assertions, however, is not measurable in general.
435/// Replacing `assert*!` with `debug_assert*!` is thus only encouraged
436/// after thorough profiling, and more importantly, only in safe code!
437///
438/// This macro is intended to work in a similar way to
439/// [`::std::debug_assert`](https://doc.rust-lang.org/std/macro.debug_assert.html).
440///
441/// # Module macros
442///
443/// * [`assert_abs_diff_gt_x`](macro@crate::assert_abs_diff_gt_x)
444/// * [`assert_abs_diff_gt_x`](macro@crate::assert_abs_diff_gt_x)
445/// * [`debug_assert_abs_diff_gt_x`](macro@crate::debug_assert_abs_diff_gt_x)
446///
447#[macro_export]
448macro_rules! debug_assert_abs_diff_gt_x {
449    ($($arg:tt)*) => {
450        if $crate::cfg!(debug_assertions) {
451            $crate::assert_abs_diff_gt_x!($($arg)*);
452        }
453    };
454}