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    borrow::Cow,
 11    cmp::{self, Ordering},
 12    ops::{AddAssign, Range, RangeInclusive},
 13    panic::Location,
 14    pin::Pin,
 15    task::{Context, Poll},
 16};
 17
 18pub use backtrace::Backtrace;
 19use futures::Future;
 20use rand::{seq::SliceRandom, Rng};
 21
 22pub use take_until::*;
 23
 24#[macro_export]
 25macro_rules! debug_panic {
 26    ( $($fmt_arg:tt)* ) => {
 27        if cfg!(debug_assertions) {
 28            panic!( $($fmt_arg)* );
 29        } else {
 30            let backtrace = $crate::Backtrace::new();
 31            log::error!("{}\n{:?}", format_args!($($fmt_arg)*), backtrace);
 32        }
 33    };
 34}
 35
 36pub fn truncate(s: &str, max_chars: usize) -> &str {
 37    match s.char_indices().nth(max_chars) {
 38        None => s,
 39        Some((idx, _)) => &s[..idx],
 40    }
 41}
 42
 43pub fn truncate_and_trailoff(s: &str, max_chars: usize) -> String {
 44    debug_assert!(max_chars >= 5);
 45
 46    let truncation_ix = s.char_indices().map(|(i, _)| i).nth(max_chars);
 47    match truncation_ix {
 48        Some(length) => s[..length].to_string() + "",
 49        None => s.to_string(),
 50    }
 51}
 52
 53pub fn post_inc<T: From<u8> + AddAssign<T> + Copy>(value: &mut T) -> T {
 54    let prev = *value;
 55    *value += T::from(1);
 56    prev
 57}
 58
 59/// Extend a sorted vector with a sorted sequence of items, maintaining the vector's sort order and
 60/// enforcing a maximum length. Sort the items according to the given callback. Before calling this,
 61/// both `vec` and `new_items` should already be sorted according to the `cmp` comparator.
 62pub fn extend_sorted<T, I, F>(vec: &mut Vec<T>, new_items: I, limit: usize, mut cmp: F)
 63where
 64    I: IntoIterator<Item = T>,
 65    F: FnMut(&T, &T) -> Ordering,
 66{
 67    let mut start_index = 0;
 68    for new_item in new_items {
 69        if let Err(i) = vec[start_index..].binary_search_by(|m| cmp(m, &new_item)) {
 70            let index = start_index + i;
 71            if vec.len() < limit {
 72                vec.insert(index, new_item);
 73            } else if index < vec.len() {
 74                vec.pop();
 75                vec.insert(index, new_item);
 76            }
 77            start_index = index;
 78        }
 79    }
 80}
 81
 82pub fn merge_json_value_into(source: serde_json::Value, target: &mut serde_json::Value) {
 83    use serde_json::Value;
 84
 85    match (source, target) {
 86        (Value::Object(source), Value::Object(target)) => {
 87            for (key, value) in source {
 88                if let Some(target) = target.get_mut(&key) {
 89                    merge_json_value_into(value, target);
 90                } else {
 91                    target.insert(key.clone(), value);
 92                }
 93            }
 94        }
 95
 96        (source, target) => *target = source,
 97    }
 98}
 99
100pub fn merge_non_null_json_value_into(source: serde_json::Value, target: &mut serde_json::Value) {
101    use serde_json::Value;
102    if let Value::Object(source_object) = source {
103        let target_object = if let Value::Object(target) = target {
104            target
105        } else {
106            *target = Value::Object(Default::default());
107            target.as_object_mut().unwrap()
108        };
109        for (key, value) in source_object {
110            if let Some(target) = target_object.get_mut(&key) {
111                merge_non_null_json_value_into(value, target);
112            } else if !value.is_null() {
113                target_object.insert(key.clone(), value);
114            }
115        }
116    } else if !source.is_null() {
117        *target = source
118    }
119}
120
121pub trait ResultExt {
122    type Ok;
123
124    fn log_err(self) -> Option<Self::Ok>;
125    fn warn_on_err(self) -> Option<Self::Ok>;
126}
127
128impl<T, E> ResultExt for Result<T, E>
129where
130    E: std::fmt::Debug,
131{
132    type Ok = T;
133
134    #[track_caller]
135    fn log_err(self) -> Option<T> {
136        match self {
137            Ok(value) => Some(value),
138            Err(error) => {
139                let caller = Location::caller();
140                log::error!("{}:{}: {:?}", caller.file(), caller.line(), error);
141                None
142            }
143        }
144    }
145
146    fn warn_on_err(self) -> Option<T> {
147        match self {
148            Ok(value) => Some(value),
149            Err(error) => {
150                log::warn!("{:?}", error);
151                None
152            }
153        }
154    }
155}
156
157pub trait TryFutureExt {
158    fn log_err(self) -> LogErrorFuture<Self>
159    where
160        Self: Sized;
161    fn warn_on_err(self) -> LogErrorFuture<Self>
162    where
163        Self: Sized;
164    fn unwrap(self) -> UnwrapFuture<Self>
165    where
166        Self: Sized;
167}
168
169impl<F, T, E> TryFutureExt for F
170where
171    F: Future<Output = Result<T, E>>,
172    E: std::fmt::Debug,
173{
174    fn log_err(self) -> LogErrorFuture<Self>
175    where
176        Self: Sized,
177    {
178        LogErrorFuture(self, log::Level::Error)
179    }
180
181    fn warn_on_err(self) -> LogErrorFuture<Self>
182    where
183        Self: Sized,
184    {
185        LogErrorFuture(self, log::Level::Warn)
186    }
187
188    fn unwrap(self) -> UnwrapFuture<Self>
189    where
190        Self: Sized,
191    {
192        UnwrapFuture(self)
193    }
194}
195
196pub struct LogErrorFuture<F>(F, log::Level);
197
198impl<F, T, E> Future for LogErrorFuture<F>
199where
200    F: Future<Output = Result<T, E>>,
201    E: std::fmt::Debug,
202{
203    type Output = Option<T>;
204
205    fn poll(self: Pin<&mut Self>, cx: &mut Context) -> Poll<Self::Output> {
206        let level = self.1;
207        let inner = unsafe { Pin::new_unchecked(&mut self.get_unchecked_mut().0) };
208        match inner.poll(cx) {
209            Poll::Ready(output) => Poll::Ready(match output {
210                Ok(output) => Some(output),
211                Err(error) => {
212                    log::log!(level, "{:?}", error);
213                    None
214                }
215            }),
216            Poll::Pending => Poll::Pending,
217        }
218    }
219}
220
221pub struct UnwrapFuture<F>(F);
222
223impl<F, T, E> Future for UnwrapFuture<F>
224where
225    F: Future<Output = Result<T, E>>,
226    E: std::fmt::Debug,
227{
228    type Output = T;
229
230    fn poll(self: Pin<&mut Self>, cx: &mut Context) -> Poll<Self::Output> {
231        let inner = unsafe { Pin::new_unchecked(&mut self.get_unchecked_mut().0) };
232        match inner.poll(cx) {
233            Poll::Ready(result) => Poll::Ready(result.unwrap()),
234            Poll::Pending => Poll::Pending,
235        }
236    }
237}
238
239struct Defer<F: FnOnce()>(Option<F>);
240
241impl<F: FnOnce()> Drop for Defer<F> {
242    fn drop(&mut self) {
243        if let Some(f) = self.0.take() {
244            f()
245        }
246    }
247}
248
249pub fn defer<F: FnOnce()>(f: F) -> impl Drop {
250    Defer(Some(f))
251}
252
253pub struct RandomCharIter<T: Rng>(T);
254
255impl<T: Rng> RandomCharIter<T> {
256    pub fn new(rng: T) -> Self {
257        Self(rng)
258    }
259}
260
261impl<T: Rng> Iterator for RandomCharIter<T> {
262    type Item = char;
263
264    fn next(&mut self) -> Option<Self::Item> {
265        if std::env::var("SIMPLE_TEXT").map_or(false, |v| !v.is_empty()) {
266            return if self.0.gen_range(0..100) < 5 {
267                Some('\n')
268            } else {
269                Some(self.0.gen_range(b'a'..b'z' + 1).into())
270            };
271        }
272
273        match self.0.gen_range(0..100) {
274            // whitespace
275            0..=19 => [' ', '\n', '\r', '\t'].choose(&mut self.0).copied(),
276            // two-byte greek letters
277            20..=32 => char::from_u32(self.0.gen_range(('α' as u32)..('ω' as u32 + 1))),
278            // // three-byte characters
279            33..=45 => ['✋', '✅', '❌', '❎', '⭐'].choose(&mut self.0).copied(),
280            // // four-byte characters
281            46..=58 => ['🍐', '🏀', '🍗', '🎉'].choose(&mut self.0).copied(),
282            // ascii letters
283            _ => Some(self.0.gen_range(b'a'..b'z' + 1).into()),
284        }
285    }
286}
287
288/// Get an embedded file as a string.
289pub fn asset_str<A: rust_embed::RustEmbed>(path: &str) -> Cow<'static, str> {
290    match A::get(path).unwrap().data {
291        Cow::Borrowed(bytes) => Cow::Borrowed(std::str::from_utf8(bytes).unwrap()),
292        Cow::Owned(bytes) => Cow::Owned(String::from_utf8(bytes).unwrap()),
293    }
294}
295
296// copy unstable standard feature option unzip
297// https://github.com/rust-lang/rust/issues/87800
298// Remove when this ship in Rust 1.66 or 1.67
299pub fn unzip_option<T, U>(option: Option<(T, U)>) -> (Option<T>, Option<U>) {
300    match option {
301        Some((a, b)) => (Some(a), Some(b)),
302        None => (None, None),
303    }
304}
305
306/// Immediately invoked function expression. Good for using the ? operator
307/// in functions which do not return an Option or Result
308#[macro_export]
309macro_rules! iife {
310    ($block:block) => {
311        (|| $block)()
312    };
313}
314
315/// Async Immediately invoked function expression. Good for using the ? operator
316/// in functions which do not return an Option or Result. Async version of above
317#[macro_export]
318macro_rules! async_iife {
319    ($block:block) => {
320        (|| async move { $block })()
321    };
322}
323
324pub trait RangeExt<T> {
325    fn sorted(&self) -> Self;
326    fn to_inclusive(&self) -> RangeInclusive<T>;
327    fn overlaps(&self, other: &Range<T>) -> bool;
328    fn contains_inclusive(&self, other: &Range<T>) -> bool;
329}
330
331impl<T: Ord + Clone> RangeExt<T> for Range<T> {
332    fn sorted(&self) -> Self {
333        cmp::min(&self.start, &self.end).clone()..cmp::max(&self.start, &self.end).clone()
334    }
335
336    fn to_inclusive(&self) -> RangeInclusive<T> {
337        self.start.clone()..=self.end.clone()
338    }
339
340    fn overlaps(&self, other: &Range<T>) -> bool {
341        self.start < other.end && other.start < self.end
342    }
343
344    fn contains_inclusive(&self, other: &Range<T>) -> bool {
345        self.start <= other.start && other.end <= self.end
346    }
347}
348
349impl<T: Ord + Clone> RangeExt<T> for RangeInclusive<T> {
350    fn sorted(&self) -> Self {
351        cmp::min(self.start(), self.end()).clone()..=cmp::max(self.start(), self.end()).clone()
352    }
353
354    fn to_inclusive(&self) -> RangeInclusive<T> {
355        self.clone()
356    }
357
358    fn overlaps(&self, other: &Range<T>) -> bool {
359        self.start() < &other.end && &other.start <= self.end()
360    }
361
362    fn contains_inclusive(&self, other: &Range<T>) -> bool {
363        self.start() <= &other.start && &other.end <= self.end()
364    }
365}
366
367#[cfg(test)]
368mod tests {
369    use super::*;
370
371    #[test]
372    fn test_extend_sorted() {
373        let mut vec = vec![];
374
375        extend_sorted(&mut vec, vec![21, 17, 13, 8, 1, 0], 5, |a, b| b.cmp(a));
376        assert_eq!(vec, &[21, 17, 13, 8, 1]);
377
378        extend_sorted(&mut vec, vec![101, 19, 17, 8, 2], 8, |a, b| b.cmp(a));
379        assert_eq!(vec, &[101, 21, 19, 17, 13, 8, 2, 1]);
380
381        extend_sorted(&mut vec, vec![1000, 19, 17, 9, 5], 8, |a, b| b.cmp(a));
382        assert_eq!(vec, &[1000, 101, 21, 19, 17, 13, 9, 8]);
383    }
384
385    #[test]
386    fn test_iife() {
387        fn option_returning_function() -> Option<()> {
388            None
389        }
390
391        let foo = iife!({
392            option_returning_function()?;
393            Some(())
394        });
395
396        assert_eq!(foo, None);
397    }
398
399    #[test]
400    fn test_trancate_and_trailoff() {
401        assert_eq!(truncate_and_trailoff("", 5), "");
402        assert_eq!(truncate_and_trailoff("èèèèèè", 7), "èèèèèè");
403        assert_eq!(truncate_and_trailoff("èèèèèè", 6), "èèèèèè");
404        assert_eq!(truncate_and_trailoff("èèèèèè", 5), "èèèèè…");
405    }
406}