assertables/assert_fn_ok/
assert_fn_ok_eq.rs

1//! Assert a function Ok(…) is equal to another.
2//!
3//! Pseudocode:<br>
4//! (a_function(a_param) ⇒ Ok(a) ⇒ a) = (b_function(b_param) ⇒ Ok(b) ⇒ b)
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 = 1;
18//! let b: i8 = 1;
19//! assert_fn_ok_eq!(f, a, f, b);
20//! ```
21//!
22//! # Module macros
23//!
24//! * [`assert_fn_ok_eq`](macro@crate::assert_fn_ok_eq)
25//! * [`assert_fn_ok_eq_as_result`](macro@crate::assert_fn_ok_eq_as_result)
26//! * [`debug_assert_fn_ok_eq`](macro@crate::debug_assert_fn_ok_eq)
27
28/// Assert a function Ok(…) is equal to another.
29///
30/// Pseudocode:<br>
31/// (a_function(a_param) ⇒ Ok(a) ⇒ a) = (b_function(b_param) ⇒ Ok(b) ⇒ b)
32///
33/// * If true, return Result `Ok(a, b)`.
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_ok_eq`](macro@crate::assert_fn_ok_eq)
43/// * [`assert_fn_ok_eq_as_result`](macro@crate::assert_fn_ok_eq_as_result)
44/// * [`debug_assert_fn_ok_eq`](macro@crate::debug_assert_fn_ok_eq)
45///
46#[macro_export]
47macro_rules! assert_fn_ok_eq_as_result {
48
49    //// Arity 1
50
51    ($a_function:path, $a_param:expr, $b_function:path, $b_param:expr $(,)?) => {
52        match (&$a_function, &$a_param, &$b_function, &$b_param) {
53            (_a_function, a_param, _b_function, b_param) => {
54                match (
55                    $a_function($a_param),
56                    $b_function($b_param)
57                ) {
58                    (Ok(a), Ok(b)) => {
59                        if a == b {
60                            Ok((a, b))
61                        } else {
62                            Err(
63                                format!(
64                                    concat!(
65                                        "assertion failed: `assert_fn_ok_eq!(a_function, a_param, b_function, b_param)`\n",
66                                        "https://docs.rs/assertables/9.8.3/assertables/macro.assert_fn_ok_eq.html\n",
67                                        " a_function label: `{}`,\n",
68                                        "    a_param label: `{}`,\n",
69                                        "    a_param debug: `{:?}`,\n",
70                                        " b_function label: `{}`,\n",
71                                        "    b_param label: `{}`,\n",
72                                        "    b_param debug: `{:?}`,\n",
73                                        "                a: `{:?}`,\n",
74                                        "                b: `{:?}`"
75                                    ),
76                                    stringify!($a_function),
77                                    stringify!($a_param),
78                                    a_param,
79                                    stringify!($b_function),
80                                    stringify!($b_param),
81                                    b_param,
82                                    a,
83                                    b
84                                )
85                            )
86                        }
87                    },
88                    (a, b) => {
89                        Err(
90                            format!(
91                                concat!(
92                                    "assertion failed: `assert_fn_ok_eq!(a_function, a_param, b_function, b_param)`\n",
93                                    "https://docs.rs/assertables/9.8.3/assertables/macro.assert_fn_ok_eq.html\n",
94                                    " a_function label: `{}`,\n",
95                                    "    a_param label: `{}`,\n",
96                                    "    a_param debug: `{:?}`,\n",
97                                    " b_function label: `{}`,\n",
98                                    "    b_param label: `{}`,\n",
99                                    "    b_param debug: `{:?}`,\n",
100                                    "                a: `{:?}`,\n",
101                                    "                b: `{:?}`"
102                                ),
103                                stringify!($a_function),
104                                stringify!($a_param),
105                                a_param,
106                                stringify!($b_function),
107                                stringify!($b_param),
108                                b_param,
109                                a,
110                                b
111                            )
112                        )
113                    }
114                }
115            }
116        }
117    };
118
119    //// Arity 0
120
121    ($a_function:path, $b_function:path) => {
122        match (
123            $a_function(),
124            $b_function()
125        ) {
126            (Ok(a), Ok(b)) => {
127                if a == b {
128                    Ok((a, b))
129                } else {
130                    Err(
131                        format!(
132                            concat!(
133                                "assertion failed: `assert_fn_ok_eq!(a_function, b_function)`\n",
134                                "https://docs.rs/assertables/9.8.3/assertables/macro.assert_fn_ok_eq.html\n",
135                                " a_function label: `{}`,\n",
136                                " b_function label: `{}`,\n",
137                                "                a: `{:?}`,\n",
138                                "                b: `{:?}`"
139                            ),
140                            stringify!($a_function),
141                            stringify!($b_function),
142                            a,
143                            b
144                        )
145                    )
146                }
147            },
148            (a, b) => {
149                Err(
150                    format!(
151                        concat!(
152                            "assertion failed: `assert_fn_ok_eq!(a_function, b_function)`\n",
153                            "https://docs.rs/assertables/9.8.3/assertables/macro.assert_fn_ok_eq.html\n",
154                            " a_function label: `{}`,\n",
155                            " b_function label: `{}`,\n",
156                            "                a: `{:?}`,\n",
157                            "                b: `{:?}`"
158                        ),
159                        stringify!($a_function),
160                        stringify!($b_function),
161                        a,
162                        b
163                    )
164                )
165            }
166        }
167    };
168
169}
170
171#[cfg(test)]
172mod test_assert_fn_ok_eq_as_result {
173    // use std::sync::Once;
174
175    mod arity_1 {
176
177        fn f(i: i8) -> Result<i8, i8> {
178            return Ok(i);
179        }
180
181        fn g(i: i8) -> Result<i8, i8> {
182            return Ok(i);
183        }
184
185        #[test]
186        fn eq() {
187            let a: i8 = 1;
188            let b: i8 = 1;
189            for _ in 0..1 {
190                let actual = assert_fn_ok_eq_as_result!(f, a, g, b);
191                assert_eq!(actual.unwrap(), (1, 1));
192            }
193        }
194
195        #[test]
196        fn ne() {
197            let a: i8 = 1;
198            let b: i8 = 2;
199            let actual = assert_fn_ok_eq_as_result!(f, a, g, b);
200            let message = concat!(
201                "assertion failed: `assert_fn_ok_eq!(a_function, a_param, b_function, b_param)`\n",
202                "https://docs.rs/assertables/9.8.3/assertables/macro.assert_fn_ok_eq.html\n",
203                " a_function label: `f`,\n",
204                "    a_param label: `a`,\n",
205                "    a_param debug: `1`,\n",
206                " b_function label: `g`,\n",
207                "    b_param label: `b`,\n",
208                "    b_param debug: `2`,\n",
209                "                a: `1`,\n",
210                "                b: `2`"
211            );
212            assert_eq!(actual.unwrap_err(), message);
213        }
214    }
215
216    mod arity_0 {
217
218        fn f() -> Result<i8, i8> {
219            return Ok(1);
220        }
221
222        fn g() -> Result<i8, i8> {
223            return Ok(2);
224        }
225
226        #[test]
227        fn eq() {
228            for _ in 0..1 {
229                let actual = assert_fn_ok_eq_as_result!(f, f);
230                assert_eq!(actual.unwrap(), (1, 1));
231            }
232        }
233
234        #[test]
235        fn ne() {
236            let actual = assert_fn_ok_eq_as_result!(f, g);
237            let message = concat!(
238                "assertion failed: `assert_fn_ok_eq!(a_function, b_function)`\n",
239                "https://docs.rs/assertables/9.8.3/assertables/macro.assert_fn_ok_eq.html\n",
240                " a_function label: `f`,\n",
241                " b_function label: `g`,\n",
242                "                a: `1`,\n",
243                "                b: `2`"
244            );
245            assert_eq!(actual.unwrap_err(), message);
246        }
247    }
248}
249
250/// Assert a function Ok(…) is equal to another.
251///
252/// Pseudocode:<br>
253/// (a_function(a_param) ⇒ Ok(a) ⇒ a) = (b_function(b_param) ⇒ Ok(b) ⇒ b)
254///
255/// * If true, return `(a, b)`.
256///
257/// * Otherwise, call [`panic!`] with a message and the values of the
258///   expressions with their debug representations.
259///
260/// # Examples
261///
262/// ```rust
263/// use assertables::*;
264/// # use std::panic;
265/// fn f(i: i8) -> Result<String, String> {
266///     match i {
267///         0..=9 => Ok(format!("{}", i)),
268///         _ => Err(format!("{:?} is out of range", i)),
269///     }
270/// }
271///
272/// # fn main() {
273/// let a: i8 = 1;
274/// let b: i8 = 1;
275/// assert_fn_ok_eq!(f, a, f, b);
276///
277/// # let result = panic::catch_unwind(|| {
278/// // This will panic
279/// let a: i8 = 1;
280/// let b: i8 = 2;
281/// assert_fn_ok_eq!(f, a, f, b);
282/// # });
283/// // assertion failed: `assert_fn_ok_eq!(a_function, a_param, b_function, b_param)`
284/// // https://docs.rs/assertables/…/assertables/macro.assert_fn_ok_eq.html
285/// //  a_function label: `f`,
286/// //     a_param label: `a`,
287/// //     a_param debug: `1`,
288/// //  b_function label: `f`,
289/// //     b_param label: `b`,
290/// //     b_param debug: `2`,
291/// //                 a: `\"1\"`,
292/// //                 b: `\"2\"`
293/// # let actual = result.unwrap_err().downcast::<String>().unwrap().to_string();
294/// # let message = concat!(
295/// #     "assertion failed: `assert_fn_ok_eq!(a_function, a_param, b_function, b_param)`\n",
296/// #     "https://docs.rs/assertables/9.8.3/assertables/macro.assert_fn_ok_eq.html\n",
297/// #     " a_function label: `f`,\n",
298/// #     "    a_param label: `a`,\n",
299/// #     "    a_param debug: `1`,\n",
300/// #     " b_function label: `f`,\n",
301/// #     "    b_param label: `b`,\n",
302/// #     "    b_param debug: `2`,\n",
303/// #     "                a: `\"1\"`,\n",
304/// #     "                b: `\"2\"`"
305/// # );
306/// # assert_eq!(actual, message);
307/// # }
308/// ```
309///
310/// # Module macros
311///
312/// * [`assert_fn_ok_eq`](macro@crate::assert_fn_ok_eq)
313/// * [`assert_fn_ok_eq_as_result`](macro@crate::assert_fn_ok_eq_as_result)
314/// * [`debug_assert_fn_ok_eq`](macro@crate::debug_assert_fn_ok_eq)
315///
316#[macro_export]
317macro_rules! assert_fn_ok_eq {
318
319    //// Arity 1
320
321    ($a_function:path, $a_param:expr, $b_function:path, $b_param:expr $(,)?) => {
322        match $crate::assert_fn_ok_eq_as_result!($a_function, $a_param, $b_function, $b_param) {
323            Ok(x) => x,
324            Err(err) => panic!("{}", err),
325        }
326    };
327
328    ($a_function:path, $a_param:expr, $b_function:path, $b_param:expr, $($message:tt)+) => {
329        match $crate::assert_fn_ok_eq_as_result!($a_function, $a_param, $b_function, $b_param) {
330            Ok(x) => x,
331            Err(err) => panic!("{}\n{}", format_args!($($message)+), err),
332        }
333    };
334
335    //// Arity 0
336
337    ($a_function:path, $b_function:path) => {
338        match $crate::assert_fn_ok_eq_as_result!($a_function, $b_function) {
339            Ok(x) => x,
340            Err(err) => panic!("{}", err),
341        }
342    };
343
344    ($a_function:path, $b_function:path, $($message:tt)+) => {
345        match $crate::assert_fn_ok_eq_as_result!($a_function, $b_function) {
346            Ok(x) => x,
347            Err(err) => panic!("{}\n{}", format_args!($($message)+), err),
348        }
349    };
350}
351
352#[cfg(test)]
353mod test_assert_fn_ok_eq {
354    use std::panic;
355
356    mod arity_1 {
357        use super::*;
358
359        fn f(i: i8) -> Result<i8, i8> {
360            return Ok(i);
361        }
362
363        fn g(i: i8) -> Result<i8, i8> {
364            return Ok(i);
365        }
366
367        #[test]
368        fn eq() {
369            let a: i8 = 1;
370            let b: i8 = 1;
371            for _ in 0..1 {
372                let actual = assert_fn_ok_eq!(f, a, g, b);
373                assert_eq!(actual, (1, 1));
374            }
375        }
376
377        #[test]
378        fn ne() {
379            let result = panic::catch_unwind(|| {
380                let a: i8 = 1;
381                let b: i8 = 2;
382                let _actual = assert_fn_ok_eq!(f, a, g, b);
383            });
384            let message = concat!(
385                "assertion failed: `assert_fn_ok_eq!(a_function, a_param, b_function, b_param)`\n",
386                "https://docs.rs/assertables/9.8.3/assertables/macro.assert_fn_ok_eq.html\n",
387                " a_function label: `f`,\n",
388                "    a_param label: `a`,\n",
389                "    a_param debug: `1`,\n",
390                " b_function label: `g`,\n",
391                "    b_param label: `b`,\n",
392                "    b_param debug: `2`,\n",
393                "                a: `1`,\n",
394                "                b: `2`"
395            );
396            assert_eq!(
397                result
398                    .unwrap_err()
399                    .downcast::<String>()
400                    .unwrap()
401                    .to_string(),
402                message
403            );
404        }
405    }
406
407    mod arity_0 {
408        use super::*;
409
410        fn f() -> Result<i8, i8> {
411            return Ok(1);
412        }
413
414        fn g() -> Result<i8, i8> {
415            return Ok(2);
416        }
417
418        #[test]
419        fn eq() {
420            for _ in 0..1 {
421                let actual = assert_fn_ok_eq!(f, f);
422                assert_eq!(actual, (1, 1));
423            }
424        }
425
426        #[test]
427        fn ne() {
428            let result = panic::catch_unwind(|| {
429                let _actual = assert_fn_ok_eq!(f, g);
430            });
431            let message = concat!(
432                "assertion failed: `assert_fn_ok_eq!(a_function, b_function)`\n",
433                "https://docs.rs/assertables/9.8.3/assertables/macro.assert_fn_ok_eq.html\n",
434                " a_function label: `f`,\n",
435                " b_function label: `g`,\n",
436                "                a: `1`,\n",
437                "                b: `2`"
438            );
439            assert_eq!(
440                result
441                    .unwrap_err()
442                    .downcast::<String>()
443                    .unwrap()
444                    .to_string(),
445                message
446            );
447        }
448    }
449}
450
451/// Assert a function Ok(…) is equal to another.
452///
453/// Pseudocode:<br>
454/// (a_function(a_param) ⇒ Ok(a) ⇒ a) = (b_function(b_param) ⇒ Ok(b) ⇒ b)
455///
456/// This macro provides the same statements as [`assert_fn_ok_eq`](macro.assert_fn_ok_eq.html),
457/// except this macro's statements are only enabled in non-optimized
458/// builds by default. An optimized build will not execute this macro's
459/// statements unless `-C debug-assertions` is passed to the compiler.
460///
461/// This macro is useful for checks that are too expensive to be present
462/// in a release build but may be helpful during development.
463///
464/// The result of expanding this macro is always type checked.
465///
466/// An unchecked assertion allows a program in an inconsistent state to
467/// keep running, which might have unexpected consequences but does not
468/// introduce unsafety as long as this only happens in safe code. The
469/// performance cost of assertions, however, is not measurable in general.
470/// Replacing `assert*!` with `debug_assert*!` is thus only encouraged
471/// after thorough profiling, and more importantly, only in safe code!
472///
473/// This macro is intended to work in a similar way to
474/// [`::std::debug_assert`](https://doc.rust-lang.org/std/macro.debug_assert.html).
475///
476/// # Module macros
477///
478/// * [`assert_fn_ok_eq`](macro@crate::assert_fn_ok_eq)
479/// * [`assert_fn_ok_eq`](macro@crate::assert_fn_ok_eq)
480/// * [`debug_assert_fn_ok_eq`](macro@crate::debug_assert_fn_ok_eq)
481///
482#[macro_export]
483macro_rules! debug_assert_fn_ok_eq {
484    ($($arg:tt)*) => {
485        if $crate::cfg!(debug_assertions) {
486            $crate::assert_fn_ok_eq!($($arg)*);
487        }
488    };
489}