assertables/assert_fn_err/
assert_fn_err_gt_x.rs

1//! Assert a function Err(…) is greater than an expression.
2//!
3//! Pseudocode:<br>
4//! (function(param) ⇒ Err(a) ⇒ a) > expr
5//!
6//! # Example
7//!
8//! ```rust
9//! use assertables::*;
10//! fn f(i: i8) -> Result<String, String> {
11//!     match i {
12//!         0..=9 => Ok(format!("{}", i)),
13//!         _ => Err(format!("{:?} is out of range", i)),
14//!     }
15//! }
16//!
17//! let a: i8 = 20;
18//! let b = String::from("10 is out of range");
19//! assert_fn_err_gt_x!(f, a, b);
20//! ```
21//!
22//! # Module macros
23//!
24//! * [`assert_fn_err_gt_x`](macro@crate::assert_fn_err_gt_x)
25//! * [`assert_fn_err_gt_x_as_result`](macro@crate::assert_fn_err_gt_x_as_result)
26//! * [`debug_assert_fn_err_gt_x`](macro@crate::debug_assert_fn_err_gt_x)
27
28/// Assert a function error is greater than an expression.
29///
30/// Pseudocode:<br>
31/// (function(param) ⇒ Err(a) ⇒ a) > expr
32///
33/// * If true, return Result `Ok(a)`.
34///
35/// * Otherwise, return Result `Err(message)`.
36///
37/// This macro is useful for runtime checks, such as checking parameters,
38/// or sanitizing inputs, or handling different results in different ways.
39///
40/// # Module macros
41///
42/// * [`assert_fn_err_gt_x`](macro@crate::assert_fn_err_gt_x)
43/// * [`assert_fn_err_gt_x_as_result`](macro@crate::assert_fn_err_gt_x_as_result)
44/// * [`debug_assert_fn_err_gt_x`](macro@crate::debug_assert_fn_err_gt_x)
45///
46#[macro_export]
47macro_rules! assert_fn_err_gt_x_as_result {
48
49    //// Arity 1
50
51    ($a_function:path, $a_param:expr, $b_expr:expr $(,)?) => {
52        match (&$a_function, &$a_param, &$b_expr) {
53            (_a_function, a_param, b_expr) => {
54                match ($a_function($a_param)) {
55                    Err(a) => {
56                        if a > $b_expr {
57                            Ok(a)
58                        } else {
59                            Err(
60                                format!(
61                                    concat!(
62                                        "assertion failed: `assert_fn_err_gt_x!(a_function, a_param, b_expr)`\n",
63                                        "https://docs.rs/assertables/", env!("CARGO_PKG_VERSION"), "/assertables/macro.assert_fn_err_gt_x.html\n",
64                                        " a_function label: `{}`,\n",
65                                        "    a_param label: `{}`,\n",
66                                        "    a_param debug: `{:?}`,\n",
67                                        "     b_expr label: `{}`,\n",
68                                        "     b_expr debug: `{:?}`,\n",
69                                        "                a: `{:?}`,\n",
70                                        "                b: `{:?}`",
71                                    ),
72                                    stringify!($a_function),
73                                    stringify!($a_param),
74                                    a_param,
75                                    stringify!($b_expr),
76                                    b_expr,
77                                    a,
78                                    $b_expr
79                                )
80                            )
81                        }
82                    },
83                    a => {
84                        Err(
85                            format!(
86                                concat!(
87                                    "assertion failed: `assert_fn_err_gt_x!(a_function, a_param, b_expr)`\n",
88                                    "https://docs.rs/assertables/", env!("CARGO_PKG_VERSION"), "/assertables/macro.assert_fn_err_gt_x.html\n",
89                                    " a_function label: `{}`,\n",
90                                    "    a_param label: `{}`,\n",
91                                    "    a_param debug: `{:?}`,\n",
92                                    "     b_expr label: `{}`,\n",
93                                    "     b_expr debug: `{:?}`,\n",
94                                    "                a: `{:?}`",
95                                ),
96                                stringify!($a_function),
97                                stringify!($a_param),
98                                a_param,
99                                stringify!($b_expr),
100                                b_expr,
101                                a
102                            )
103                        )
104                    }
105                }
106            }
107        }
108    };
109
110    //// Arity 0
111
112    ($a_function:path, $b_expr:expr $(,)?) => {
113        match (&$a_function, &$b_expr) {
114            (_a_function, b_expr) => {
115                match ($a_function()) {
116                    Err(a) => {
117                        if a > $b_expr {
118                            Ok(a)
119                        } else {
120                            Err(
121                                format!(
122                                    concat!(
123                                        "assertion failed: `assert_fn_err_gt_x!(a_function, b_expr)`\n",
124                                        "https://docs.rs/assertables/", env!("CARGO_PKG_VERSION"), "/assertables/macro.assert_fn_err_gt_x.html\n",
125                                        " a_function label: `{}`,\n",
126                                        "     b_expr label: `{}`,\n",
127                                        "     b_expr debug: `{:?}`,\n",
128                                        "                a: `{:?}`,\n",
129                                        "                b: `{:?}`",
130                                    ),
131                                    stringify!($a_function),
132                                    stringify!($b_expr),
133                                    b_expr,
134                                    a,
135                                    $b_expr
136                                )
137                            )
138                        }
139                    },
140                    a => {
141                        Err(
142                            format!(
143                                concat!(
144                                    "assertion failed: `assert_fn_err_gt_x!(a_function, b_expr)`\n",
145                                    "https://docs.rs/assertables/", env!("CARGO_PKG_VERSION"), "/assertables/macro.assert_fn_err_gt_x.html\n",
146                                    " a_function label: `{}`,\n",
147                                    "     b_expr label: `{}`,\n",
148                                    "     b_expr debug: `{:?}`,\n",
149                                    "                a: `{:?}`",
150                                ),
151                                stringify!($a_function),
152                                stringify!($b_expr),
153                                b_expr,
154                                a
155                            )
156                        )
157                    }
158                }
159            }
160        }
161    };
162
163}
164
165#[cfg(test)]
166mod test_assert_fn_err_gt_x_as_result {
167    // use std::sync::Once;
168
169    mod arity_1 {
170
171        fn f(i: i8) -> Result<i8, i8> {
172            Err(i)
173        }
174
175        #[test]
176        fn gt() {
177            let a: i8 = 2;
178            let b: i8 = 1;
179            for _ in 0..1 {
180                let actual = assert_fn_err_gt_x_as_result!(f, a, b);
181                assert_eq!(actual.unwrap(), 2);
182            }
183        }
184
185        #[test]
186        fn eq() {
187            let a: i8 = 1;
188            let b: i8 = 1;
189            let actual = assert_fn_err_gt_x_as_result!(f, a, b);
190            let message = concat!(
191                "assertion failed: `assert_fn_err_gt_x!(a_function, a_param, b_expr)`\n",
192                "https://docs.rs/assertables/",
193                env!("CARGO_PKG_VERSION"),
194                "/assertables/macro.assert_fn_err_gt_x.html\n",
195                " a_function label: `f`,\n",
196                "    a_param label: `a`,\n",
197                "    a_param debug: `1`,\n",
198                "     b_expr label: `b`,\n",
199                "     b_expr debug: `1`,\n",
200                "                a: `1`,\n",
201                "                b: `1`"
202            );
203            assert_eq!(actual.unwrap_err(), message);
204        }
205
206        #[test]
207        fn lt() {
208            let a: i8 = 1;
209            let b: i8 = 2;
210            let actual = assert_fn_err_gt_x_as_result!(f, a, b);
211            let message = concat!(
212                "assertion failed: `assert_fn_err_gt_x!(a_function, a_param, b_expr)`\n",
213                "https://docs.rs/assertables/",
214                env!("CARGO_PKG_VERSION"),
215                "/assertables/macro.assert_fn_err_gt_x.html\n",
216                " a_function label: `f`,\n",
217                "    a_param label: `a`,\n",
218                "    a_param debug: `1`,\n",
219                "     b_expr label: `b`,\n",
220                "     b_expr debug: `2`,\n",
221                "                a: `1`,\n",
222                "                b: `2`"
223            );
224            assert_eq!(actual.unwrap_err(), message);
225        }
226    }
227
228    mod arity_0 {
229
230        fn f() -> Result<i8, i8> {
231            Err(1)
232        }
233
234        #[test]
235        fn gt() {
236            let b: i8 = 0;
237            for _ in 0..1 {
238                let actual = assert_fn_err_gt_x_as_result!(f, b);
239                assert_eq!(actual.unwrap(), 1);
240            }
241        }
242
243        #[test]
244        fn eq() {
245            let b: i8 = 1;
246            let actual = assert_fn_err_gt_x_as_result!(f, b);
247            let message = concat!(
248                "assertion failed: `assert_fn_err_gt_x!(a_function, b_expr)`\n",
249                "https://docs.rs/assertables/",
250                env!("CARGO_PKG_VERSION"),
251                "/assertables/macro.assert_fn_err_gt_x.html\n",
252                " a_function label: `f`,\n",
253                "     b_expr label: `b`,\n",
254                "     b_expr debug: `1`,\n",
255                "                a: `1`,\n",
256                "                b: `1`"
257            );
258            assert_eq!(actual.unwrap_err(), message);
259        }
260
261        #[test]
262        fn lt() {
263            let b: i8 = 2;
264            let actual = assert_fn_err_gt_x_as_result!(f, b);
265            let message = concat!(
266                "assertion failed: `assert_fn_err_gt_x!(a_function, b_expr)`\n",
267                "https://docs.rs/assertables/",
268                env!("CARGO_PKG_VERSION"),
269                "/assertables/macro.assert_fn_err_gt_x.html\n",
270                " a_function label: `f`,\n",
271                "     b_expr label: `b`,\n",
272                "     b_expr debug: `2`,\n",
273                "                a: `1`,\n",
274                "                b: `2`"
275            );
276            assert_eq!(actual.unwrap_err(), message);
277        }
278    }
279}
280
281/// Assert a function error is greater than an expression.
282///
283/// Pseudocode:<br>
284/// (function(param) ⇒ Err(a) ⇒ a) > expr
285///
286/// * If true, return `a`.
287///
288/// * Otherwise, call [`panic!`] with a message and the values of the
289///   expressions with their debug representations.
290///
291/// # Examples
292///
293/// ```rust
294/// use assertables::*;
295/// # use std::panic;
296/// fn f(i: i8) -> Result<String, String> {
297///     match i {
298///         0..=9 => Ok(format!("{}", i)),
299///         _ => Err(format!("{:?} is out of range", i)),
300///     }
301/// }
302///
303/// # fn main() {
304/// let a: i8 = 20;
305/// let b = String::from("10 is out of range");
306/// assert_fn_err_gt_x!(f, a, b);
307///
308/// # let result = panic::catch_unwind(|| {
309/// // This will panic
310/// let a: i8 = 10;
311/// let b = String::from("20 is out of range");
312/// assert_fn_err_gt_x!(f, a, b);
313/// # });
314/// // assertion failed: `assert_fn_err_gt_x!(a_function, a_param, b_expr)`
315/// // https://docs.rs/assertables/9.7.0/assertables/macro.assert_fn_err_gt_x.html
316/// //  a_function label: `f`,
317/// //     a_param label: `a`,
318/// //     a_param debug: `10`,
319/// //      b_expr label: `b`,
320/// //      b_expr debug: `\"20 is out of range\"`,
321/// //                 a: `\"10 is out of range\"`,
322/// //                 b: `\"20 is out of range\"`
323/// # let actual = result.unwrap_err().downcast::<String>().unwrap().to_string();
324/// # let message = concat!(
325/// #     "assertion failed: `assert_fn_err_gt_x!(a_function, a_param, b_expr)`\n",
326/// #     "https://docs.rs/assertables/", env!("CARGO_PKG_VERSION"), "/assertables/macro.assert_fn_err_gt_x.html\n",
327/// #     " a_function label: `f`,\n",
328/// #     "    a_param label: `a`,\n",
329/// #     "    a_param debug: `10`,\n",
330/// #     "     b_expr label: `b`,\n",
331/// #     "     b_expr debug: `\"20 is out of range\"`,\n",
332/// #     "                a: `\"10 is out of range\"`,\n",
333/// #     "                b: `\"20 is out of range\"`"
334/// # );
335/// # assert_eq!(actual, message);
336/// # }
337/// ```
338///
339/// # Module macros
340///
341/// * [`assert_fn_err_gt_x`](macro@crate::assert_fn_err_gt_x)
342/// * [`assert_fn_err_gt_x_as_result`](macro@crate::assert_fn_err_gt_x_as_result)
343/// * [`debug_assert_fn_err_gt_x`](macro@crate::debug_assert_fn_err_gt_x)
344///
345#[macro_export]
346macro_rules! assert_fn_err_gt_x {
347
348    //// Arity 1
349
350    ($a_function:path, $a_param:expr, $b_expr:expr $(,)?) => {
351        match $crate::assert_fn_err_gt_x_as_result!($a_function, $a_param, $b_expr) {
352            Ok(x) => x,
353            Err(err) => panic!("{}", err),
354        }
355    };
356
357    ($a_function:path, $a_param:expr, $b_expr:expr, $($message:tt)+) => {
358        match $crate::assert_fn_err_gt_x_as_result!($a_function, $a_param, $b_expr) {
359            Ok(x) => x,
360            Err(err) => panic!("{}\n{}", format_args!($($message)+), err),
361        }
362    };
363
364    //// Arity 0
365
366    ($a_function:path, $b_expr:expr $(,)?) => {
367        match $crate::assert_fn_err_gt_x_as_result!($a_function, $b_expr) {
368            Ok(x) => x,
369            Err(err) => panic!("{}", err),
370        }
371    };
372
373    ($a_function:path, $b_expr:expr, $($message:tt)+) => {
374        match $crate::assert_fn_err_gt_x_as_result!($a_function, $b_expr) {
375            Ok(x) => x,
376            Err(err) => panic!("{}\n{}", format_args!($($message)+), err),
377        }
378    };
379}
380
381#[cfg(test)]
382mod test_assert_fn_err_gt_x {
383    use std::panic;
384
385    mod arity_1 {
386        use super::*;
387
388        fn f(i: i8) -> Result<i8, i8> {
389            Err(i)
390        }
391
392        #[test]
393        fn gt() {
394            let a: i8 = 2;
395            let b: i8 = 1;
396            for _ in 0..1 {
397                let actual = assert_fn_err_gt_x!(f, a, b);
398                assert_eq!(actual, 2);
399            }
400        }
401
402        #[test]
403        fn eq() {
404            let result = panic::catch_unwind(|| {
405                let a: i8 = 1;
406                let b: i8 = 1;
407                let _actual = assert_fn_err_gt_x!(f, a, b);
408            });
409            let message = concat!(
410                "assertion failed: `assert_fn_err_gt_x!(a_function, a_param, b_expr)`\n",
411                "https://docs.rs/assertables/",
412                env!("CARGO_PKG_VERSION"),
413                "/assertables/macro.assert_fn_err_gt_x.html\n",
414                " a_function label: `f`,\n",
415                "    a_param label: `a`,\n",
416                "    a_param debug: `1`,\n",
417                "     b_expr label: `b`,\n",
418                "     b_expr debug: `1`,\n",
419                "                a: `1`,\n",
420                "                b: `1`"
421            );
422            assert_eq!(
423                result
424                    .unwrap_err()
425                    .downcast::<String>()
426                    .unwrap()
427                    .to_string(),
428                message
429            );
430        }
431
432        #[test]
433        fn lt() {
434            let result = panic::catch_unwind(|| {
435                let a: i8 = 1;
436                let b: i8 = 2;
437                let _actual = assert_fn_err_gt_x!(f, a, b);
438            });
439            let message = concat!(
440                "assertion failed: `assert_fn_err_gt_x!(a_function, a_param, b_expr)`\n",
441                "https://docs.rs/assertables/",
442                env!("CARGO_PKG_VERSION"),
443                "/assertables/macro.assert_fn_err_gt_x.html\n",
444                " a_function label: `f`,\n",
445                "    a_param label: `a`,\n",
446                "    a_param debug: `1`,\n",
447                "     b_expr label: `b`,\n",
448                "     b_expr debug: `2`,\n",
449                "                a: `1`,\n",
450                "                b: `2`"
451            );
452            assert_eq!(
453                result
454                    .unwrap_err()
455                    .downcast::<String>()
456                    .unwrap()
457                    .to_string(),
458                message
459            );
460        }
461    }
462
463    mod arity_0 {
464        use super::*;
465
466        fn f() -> Result<i8, i8> {
467            Err(1)
468        }
469
470        #[test]
471        fn gt() {
472            let b: i8 = 0;
473            for _ in 0..1 {
474                let actual = assert_fn_err_gt_x!(f, b);
475                assert_eq!(actual, 1);
476            }
477        }
478
479        #[test]
480        fn eq() {
481            let result = panic::catch_unwind(|| {
482                let b: i8 = 1;
483                let _actual = assert_fn_err_gt_x!(f, b);
484            });
485            let message = concat!(
486                "assertion failed: `assert_fn_err_gt_x!(a_function, b_expr)`\n",
487                "https://docs.rs/assertables/",
488                env!("CARGO_PKG_VERSION"),
489                "/assertables/macro.assert_fn_err_gt_x.html\n",
490                " a_function label: `f`,\n",
491                "     b_expr label: `b`,\n",
492                "     b_expr debug: `1`,\n",
493                "                a: `1`,\n",
494                "                b: `1`"
495            );
496            assert_eq!(
497                result
498                    .unwrap_err()
499                    .downcast::<String>()
500                    .unwrap()
501                    .to_string(),
502                message
503            );
504        }
505
506        #[test]
507        fn lt() {
508            let result = panic::catch_unwind(|| {
509                let b: i8 = 2;
510                let _actual = assert_fn_err_gt_x!(f, b);
511            });
512            let message = concat!(
513                "assertion failed: `assert_fn_err_gt_x!(a_function, b_expr)`\n",
514                "https://docs.rs/assertables/",
515                env!("CARGO_PKG_VERSION"),
516                "/assertables/macro.assert_fn_err_gt_x.html\n",
517                " a_function label: `f`,\n",
518                "     b_expr label: `b`,\n",
519                "     b_expr debug: `2`,\n",
520                "                a: `1`,\n",
521                "                b: `2`"
522            );
523            assert_eq!(
524                result
525                    .unwrap_err()
526                    .downcast::<String>()
527                    .unwrap()
528                    .to_string(),
529                message
530            );
531        }
532    }
533}
534
535/// Assert a function error is greater than an expression.
536///
537/// Pseudocode:<br>
538/// (function(param) ⇒ Err(a) ⇒ a) > expr
539///
540/// This macro provides the same statements as [`assert_fn_err_gt_x`](macro.assert_fn_err_gt_x.html),
541/// except this macro's statements are only enabled in non-optimized
542/// builds by default. An optimized build will not execute this macro's
543/// statements unless `-C debug-assertions` is passed to the compiler.
544///
545/// This macro is useful for checks that are too expensive to be present
546/// in a release build but may be helpful during development.
547///
548/// The result of expanding this macro is always type checked.
549///
550/// An unchecked assertion allows a program in an inconsistent state to
551/// keep running, which might have unexpected consequences but does not
552/// introduce unsafety as long as this only happens in safe code. The
553/// performance cost of assertions, however, is not measurable in general.
554/// Replacing `assert*!` with `debug_assert*!` is thus only encouraged
555/// after thorough profiling, and more importantly, only in safe code!
556///
557/// This macro is intended to work in a similar way to
558/// [`::std::debug_assert`](https://doc.rust-lang.org/std/macro.debug_assert.html).
559///
560/// # Module macros
561///
562/// * [`assert_fn_err_gt_x`](macro@crate::assert_fn_err_gt_x)
563/// * [`assert_fn_err_gt_x`](macro@crate::assert_fn_err_gt_x)
564/// * [`debug_assert_fn_err_gt_x`](macro@crate::debug_assert_fn_err_gt_x)
565///
566#[macro_export]
567macro_rules! debug_assert_fn_err_gt_x {
568    ($($arg:tt)*) => {
569        if $crate::cfg!(debug_assertions) {
570            $crate::assert_fn_err_gt_x!($($arg)*);
571        }
572    };
573}