util.rs

  1pub mod channel;
  2pub mod fs;
  3pub mod github;
  4pub mod http;
  5pub mod paths;
  6#[cfg(any(test, feature = "test-support"))]
  7pub mod test;
  8
  9use std::{
 10    cmp::{self, Ordering},
 11    ops::{AddAssign, Range, RangeInclusive},
 12    panic::Location,
 13    pin::Pin,
 14    task::{Context, Poll},
 15};
 16
 17pub use backtrace::Backtrace;
 18use futures::Future;
 19use rand::{seq::SliceRandom, Rng};
 20
 21pub use take_until::*;
 22
 23#[macro_export]
 24macro_rules! debug_panic {
 25    ( $($fmt_arg:tt)* ) => {
 26        if cfg!(debug_assertions) {
 27            panic!( $($fmt_arg)* );
 28        } else {
 29            let backtrace = $crate::Backtrace::new();
 30            log::error!("{}\n{:?}", format_args!($($fmt_arg)*), backtrace);
 31        }
 32    };
 33}
 34
 35pub fn truncate(s: &str, max_chars: usize) -> &str {
 36    match s.char_indices().nth(max_chars) {
 37        None => s,
 38        Some((idx, _)) => &s[..idx],
 39    }
 40}
 41
 42pub fn truncate_and_trailoff(s: &str, max_chars: usize) -> String {
 43    debug_assert!(max_chars >= 5);
 44
 45    let truncation_ix = s.char_indices().map(|(i, _)| i).nth(max_chars);
 46    match truncation_ix {
 47        Some(length) => s[..length].to_string() + "",
 48        None => s.to_string(),
 49    }
 50}
 51
 52pub fn post_inc<T: From<u8> + AddAssign<T> + Copy>(value: &mut T) -> T {
 53    let prev = *value;
 54    *value += T::from(1);
 55    prev
 56}
 57
 58/// Extend a sorted vector with a sorted sequence of items, maintaining the vector's sort order and
 59/// enforcing a maximum length. Sort the items according to the given callback. Before calling this,
 60/// both `vec` and `new_items` should already be sorted according to the `cmp` comparator.
 61pub fn extend_sorted<T, I, F>(vec: &mut Vec<T>, new_items: I, limit: usize, mut cmp: F)
 62where
 63    I: IntoIterator<Item = T>,
 64    F: FnMut(&T, &T) -> Ordering,
 65{
 66    let mut start_index = 0;
 67    for new_item in new_items {
 68        if let Err(i) = vec[start_index..].binary_search_by(|m| cmp(m, &new_item)) {
 69            let index = start_index + i;
 70            if vec.len() < limit {
 71                vec.insert(index, new_item);
 72            } else if index < vec.len() {
 73                vec.pop();
 74                vec.insert(index, new_item);
 75            }
 76            start_index = index;
 77        }
 78    }
 79}
 80
 81pub fn merge_json_value_into(source: serde_json::Value, target: &mut serde_json::Value) {
 82    use serde_json::Value;
 83
 84    match (source, target) {
 85        (Value::Object(source), Value::Object(target)) => {
 86            for (key, value) in source {
 87                if let Some(target) = target.get_mut(&key) {
 88                    merge_json_value_into(value, target);
 89                } else {
 90                    target.insert(key.clone(), value);
 91                }
 92            }
 93        }
 94
 95        (source, target) => *target = source,
 96    }
 97}
 98
 99pub fn merge_non_null_json_value_into(source: serde_json::Value, target: &mut serde_json::Value) {
100    use serde_json::Value;
101    if let Value::Object(source_object) = source {
102        let target_object = if let Value::Object(target) = target {
103            target
104        } else {
105            *target = Value::Object(Default::default());
106            target.as_object_mut().unwrap()
107        };
108        for (key, value) in source_object {
109            if let Some(target) = target_object.get_mut(&key) {
110                merge_non_null_json_value_into(value, target);
111            } else if !value.is_null() {
112                target_object.insert(key.clone(), value);
113            }
114        }
115    } else if !source.is_null() {
116        *target = source
117    }
118}
119
120pub trait ResultExt {
121    type Ok;
122
123    fn log_err(self) -> Option<Self::Ok>;
124    fn warn_on_err(self) -> Option<Self::Ok>;
125}
126
127impl<T, E> ResultExt for Result<T, E>
128where
129    E: std::fmt::Debug,
130{
131    type Ok = T;
132
133    #[track_caller]
134    fn log_err(self) -> Option<T> {
135        match self {
136            Ok(value) => Some(value),
137            Err(error) => {
138                let caller = Location::caller();
139                log::error!("{}:{}: {:?}", caller.file(), caller.line(), error);
140                None
141            }
142        }
143    }
144
145    fn warn_on_err(self) -> Option<T> {
146        match self {
147            Ok(value) => Some(value),
148            Err(error) => {
149                log::warn!("{:?}", error);
150                None
151            }
152        }
153    }
154}
155
156pub trait TryFutureExt {
157    fn log_err(self) -> LogErrorFuture<Self>
158    where
159        Self: Sized;
160    fn warn_on_err(self) -> LogErrorFuture<Self>
161    where
162        Self: Sized;
163    fn unwrap(self) -> UnwrapFuture<Self>
164    where
165        Self: Sized;
166}
167
168impl<F, T, E> TryFutureExt for F
169where
170    F: Future<Output = Result<T, E>>,
171    E: std::fmt::Debug,
172{
173    fn log_err(self) -> LogErrorFuture<Self>
174    where
175        Self: Sized,
176    {
177        LogErrorFuture(self, log::Level::Error)
178    }
179
180    fn warn_on_err(self) -> LogErrorFuture<Self>
181    where
182        Self: Sized,
183    {
184        LogErrorFuture(self, log::Level::Warn)
185    }
186
187    fn unwrap(self) -> UnwrapFuture<Self>
188    where
189        Self: Sized,
190    {
191        UnwrapFuture(self)
192    }
193}
194
195pub struct LogErrorFuture<F>(F, log::Level);
196
197impl<F, T, E> Future for LogErrorFuture<F>
198where
199    F: Future<Output = Result<T, E>>,
200    E: std::fmt::Debug,
201{
202    type Output = Option<T>;
203
204    fn poll(self: Pin<&mut Self>, cx: &mut Context) -> Poll<Self::Output> {
205        let level = self.1;
206        let inner = unsafe { Pin::new_unchecked(&mut self.get_unchecked_mut().0) };
207        match inner.poll(cx) {
208            Poll::Ready(output) => Poll::Ready(match output {
209                Ok(output) => Some(output),
210                Err(error) => {
211                    log::log!(level, "{:?}", error);
212                    None
213                }
214            }),
215            Poll::Pending => Poll::Pending,
216        }
217    }
218}
219
220pub struct UnwrapFuture<F>(F);
221
222impl<F, T, E> Future for UnwrapFuture<F>
223where
224    F: Future<Output = Result<T, E>>,
225    E: std::fmt::Debug,
226{
227    type Output = T;
228
229    fn poll(self: Pin<&mut Self>, cx: &mut Context) -> Poll<Self::Output> {
230        let inner = unsafe { Pin::new_unchecked(&mut self.get_unchecked_mut().0) };
231        match inner.poll(cx) {
232            Poll::Ready(result) => Poll::Ready(result.unwrap()),
233            Poll::Pending => Poll::Pending,
234        }
235    }
236}
237
238struct Defer<F: FnOnce()>(Option<F>);
239
240impl<F: FnOnce()> Drop for Defer<F> {
241    fn drop(&mut self) {
242        if let Some(f) = self.0.take() {
243            f()
244        }
245    }
246}
247
248pub fn defer<F: FnOnce()>(f: F) -> impl Drop {
249    Defer(Some(f))
250}
251
252pub struct RandomCharIter<T: Rng>(T);
253
254impl<T: Rng> RandomCharIter<T> {
255    pub fn new(rng: T) -> Self {
256        Self(rng)
257    }
258}
259
260impl<T: Rng> Iterator for RandomCharIter<T> {
261    type Item = char;
262
263    fn next(&mut self) -> Option<Self::Item> {
264        if std::env::var("SIMPLE_TEXT").map_or(false, |v| !v.is_empty()) {
265            return if self.0.gen_range(0..100) < 5 {
266                Some('\n')
267            } else {
268                Some(self.0.gen_range(b'a'..b'z' + 1).into())
269            };
270        }
271
272        match self.0.gen_range(0..100) {
273            // whitespace
274            0..=19 => [' ', '\n', '\r', '\t'].choose(&mut self.0).copied(),
275            // two-byte greek letters
276            20..=32 => char::from_u32(self.0.gen_range(('α' as u32)..('ω' as u32 + 1))),
277            // // three-byte characters
278            33..=45 => ['✋', '✅', '❌', '❎', '⭐'].choose(&mut self.0).copied(),
279            // // four-byte characters
280            46..=58 => ['🍐', '🏀', '🍗', '🎉'].choose(&mut self.0).copied(),
281            // ascii letters
282            _ => Some(self.0.gen_range(b'a'..b'z' + 1).into()),
283        }
284    }
285}
286
287// copy unstable standard feature option unzip
288// https://github.com/rust-lang/rust/issues/87800
289// Remove when this ship in Rust 1.66 or 1.67
290pub fn unzip_option<T, U>(option: Option<(T, U)>) -> (Option<T>, Option<U>) {
291    match option {
292        Some((a, b)) => (Some(a), Some(b)),
293        None => (None, None),
294    }
295}
296
297/// Immediately invoked function expression. Good for using the ? operator
298/// in functions which do not return an Option or Result
299#[macro_export]
300macro_rules! iife {
301    ($block:block) => {
302        (|| $block)()
303    };
304}
305
306/// Async Immediately invoked function expression. Good for using the ? operator
307/// in functions which do not return an Option or Result. Async version of above
308#[macro_export]
309macro_rules! async_iife {
310    ($block:block) => {
311        (|| async move { $block })()
312    };
313}
314
315pub trait RangeExt<T> {
316    fn sorted(&self) -> Self;
317    fn to_inclusive(&self) -> RangeInclusive<T>;
318    fn overlaps(&self, other: &Range<T>) -> bool;
319    fn contains_inclusive(&self, other: &Range<T>) -> bool;
320}
321
322impl<T: Ord + Clone> RangeExt<T> for Range<T> {
323    fn sorted(&self) -> Self {
324        cmp::min(&self.start, &self.end).clone()..cmp::max(&self.start, &self.end).clone()
325    }
326
327    fn to_inclusive(&self) -> RangeInclusive<T> {
328        self.start.clone()..=self.end.clone()
329    }
330
331    fn overlaps(&self, other: &Range<T>) -> bool {
332        self.start < other.end && other.start < self.end
333    }
334
335    fn contains_inclusive(&self, other: &Range<T>) -> bool {
336        self.start <= other.start && other.end <= self.end
337    }
338}
339
340impl<T: Ord + Clone> RangeExt<T> for RangeInclusive<T> {
341    fn sorted(&self) -> Self {
342        cmp::min(self.start(), self.end()).clone()..=cmp::max(self.start(), self.end()).clone()
343    }
344
345    fn to_inclusive(&self) -> RangeInclusive<T> {
346        self.clone()
347    }
348
349    fn overlaps(&self, other: &Range<T>) -> bool {
350        self.start() < &other.end && &other.start <= self.end()
351    }
352
353    fn contains_inclusive(&self, other: &Range<T>) -> bool {
354        self.start() <= &other.start && &other.end <= self.end()
355    }
356}
357
358#[cfg(test)]
359mod tests {
360    use super::*;
361
362    #[test]
363    fn test_extend_sorted() {
364        let mut vec = vec![];
365
366        extend_sorted(&mut vec, vec![21, 17, 13, 8, 1, 0], 5, |a, b| b.cmp(a));
367        assert_eq!(vec, &[21, 17, 13, 8, 1]);
368
369        extend_sorted(&mut vec, vec![101, 19, 17, 8, 2], 8, |a, b| b.cmp(a));
370        assert_eq!(vec, &[101, 21, 19, 17, 13, 8, 2, 1]);
371
372        extend_sorted(&mut vec, vec![1000, 19, 17, 9, 5], 8, |a, b| b.cmp(a));
373        assert_eq!(vec, &[1000, 101, 21, 19, 17, 13, 9, 8]);
374    }
375
376    #[test]
377    fn test_iife() {
378        fn option_returning_function() -> Option<()> {
379            None
380        }
381
382        let foo = iife!({
383            option_returning_function()?;
384            Some(())
385        });
386
387        assert_eq!(foo, None);
388    }
389
390    #[test]
391    fn test_trancate_and_trailoff() {
392        assert_eq!(truncate_and_trailoff("", 5), "");
393        assert_eq!(truncate_and_trailoff("èèèèèè", 7), "èèèèèè");
394        assert_eq!(truncate_and_trailoff("èèèèèè", 6), "èèèèèè");
395        assert_eq!(truncate_and_trailoff("èèèèèè", 5), "èèèèè…");
396    }
397}