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1
2 #![feature(const_fn)]
3
4 #![warn(clippy, clippy_pedantic)]
5 #![allow(blacklisted_name, unused, print_stdout, non_ascii_literal, new_without_default,
6 new_without_default_derive, missing_docs_in_private_items, needless_pass_by_value)]
7
8 use std::collections::BTreeMap;
9 use std::collections::HashMap;
10 use std::collections::HashSet;
11 use std::collections::VecDeque;
12 use std::ops::Mul;
13 use std::iter::FromIterator;
14 use std::rc::{self, Rc};
15 use std::sync::{self, Arc};
16
17 pub struct T;
18
19 impl T {
20 pub fn add(self, other: T) -> T { self }
21
22 pub(crate) fn drop(&mut self) { } // no error, not public interfact
23 fn neg(self) -> Self { self } // no error, private function
24 fn eq(&self, other: T) -> bool { true } // no error, private function
25
26 fn sub(&self, other: T) -> &T { self } // no error, self is a ref
27 fn div(self) -> T { self } // no error, different #arguments
28 fn rem(self, other: T) { } // no error, wrong return type
29
30 fn into_u32(self) -> u32 { 0 } // fine
31 fn into_u16(&self) -> u16 { 0 }
32
33 fn to_something(self) -> u32 { 0 }
34
35 fn new(self) {}
36 }
37
38 struct Lt<'a> {
39 foo: &'a u32,
40 }
41
42 impl<'a> Lt<'a> {
43 // The lifetime is different, but that’s irrelevant, see #734
44 #[allow(needless_lifetimes)]
45 pub fn new<'b>(s: &'b str) -> Lt<'b> { unimplemented!() }
46 }
47
48 struct Lt2<'a> {
49 foo: &'a u32,
50 }
51
52 impl<'a> Lt2<'a> {
53 // The lifetime is different, but that’s irrelevant, see #734
54 pub fn new(s: &str) -> Lt2 { unimplemented!() }
55 }
56
57 struct Lt3<'a> {
58 foo: &'a u32,
59 }
60
61 impl<'a> Lt3<'a> {
62 // The lifetime is different, but that’s irrelevant, see #734
63 pub fn new() -> Lt3<'static> { unimplemented!() }
64 }
65
66 #[derive(Clone,Copy)]
67 struct U;
68
69 impl U {
70 fn new() -> Self { U }
71 fn to_something(self) -> u32 { 0 } // ok because U is Copy
72 }
73
74 struct V<T> {
75 _dummy: T
76 }
77
78 impl<T> V<T> {
79 fn new() -> Option<V<T>> { None }
80 }
81
82 impl Mul<T> for T {
83 type Output = T;
84 fn mul(self, other: T) -> T { self } // no error, obviously
85 }
86
87 /// Utility macro to test linting behavior in `option_methods()`
88 /// The lints included in `option_methods()` should not lint if the call to map is partially
89 /// within a macro
90 macro_rules! opt_map {
91 ($opt:expr, $map:expr) => {($opt).map($map)};
92 }
93
94 /// Checks implementation of the following lints:
95 /// * `OPTION_MAP_UNWRAP_OR`
96 /// * `OPTION_MAP_UNWRAP_OR_ELSE`
97 /// * `OPTION_MAP_OR_NONE`
98 fn option_methods() {
99 let opt = Some(1);
100
101 // Check OPTION_MAP_UNWRAP_OR
102 // single line case
103 let _ = opt.map(|x| x + 1)
104
105 .unwrap_or(0); // should lint even though this call is on a separate line
106 // multi line cases
107 let _ = opt.map(|x| {
108 x + 1
109 }
110 ).unwrap_or(0);
111 let _ = opt.map(|x| x + 1)
112 .unwrap_or({
113 0
114 });
115 // single line `map(f).unwrap_or(None)` case
116 let _ = opt.map(|x| Some(x + 1)).unwrap_or(None);
117 // multiline `map(f).unwrap_or(None)` cases
118 let _ = opt.map(|x| {
119 Some(x + 1)
120 }
121 ).unwrap_or(None);
122 let _ = opt
123 .map(|x| Some(x + 1))
124 .unwrap_or(None);
125 // macro case
126 let _ = opt_map!(opt, |x| x + 1).unwrap_or(0); // should not lint
127
128 // Check OPTION_MAP_UNWRAP_OR_ELSE
129 // single line case
130 let _ = opt.map(|x| x + 1)
131
132 .unwrap_or_else(|| 0); // should lint even though this call is on a separate line
133 // multi line cases
134 let _ = opt.map(|x| {
135 x + 1
136 }
137 ).unwrap_or_else(|| 0);
138 let _ = opt.map(|x| x + 1)
139 .unwrap_or_else(||
140 0
141 );
142 // macro case
143 let _ = opt_map!(opt, |x| x + 1).unwrap_or_else(|| 0); // should not lint
144
145 // Check OPTION_MAP_OR_NONE
146 // single line case
147 let _ = opt.map_or(None, |x| Some(x + 1));
148 // multi line case
149 let _ = opt.map_or(None, |x| {
150 Some(x + 1)
151 }
152 );
153 }
154
155 /// Checks implementation of the following lints:
156 /// * `RESULT_MAP_UNWRAP_OR_ELSE`
157 fn result_methods() {
158 let res: Result<i32, ()> = Ok(1);
159
160 // Check RESULT_MAP_UNWRAP_OR_ELSE
161 // single line case
162 let _ = res.map(|x| x + 1)
163
164 .unwrap_or_else(|e| 0); // should lint even though this call is on a separate line
165 // multi line cases
166 let _ = res.map(|x| {
167 x + 1
168 }
169 ).unwrap_or_else(|e| 0);
170 let _ = res.map(|x| x + 1)
171 .unwrap_or_else(|e|
172 0
173 );
174 // macro case
175 let _ = opt_map!(res, |x| x + 1).unwrap_or_else(|e| 0); // should not lint
176 }
177
178 /// Struct to generate false positives for things with .iter()
179 #[derive(Copy, Clone)]
180 struct HasIter;
181
182 impl HasIter {
183 fn iter(self) -> IteratorFalsePositives {
184 IteratorFalsePositives { foo: 0 }
185 }
186
187 fn iter_mut(self) -> IteratorFalsePositives {
188 IteratorFalsePositives { foo: 0 }
189 }
190 }
191
192 /// Struct to generate false positive for Iterator-based lints
193 #[derive(Copy, Clone)]
194 struct IteratorFalsePositives {
195 foo: u32,
196 }
197
198 impl IteratorFalsePositives {
199 fn filter(self) -> IteratorFalsePositives {
200 self
201 }
202
203 fn next(self) -> IteratorFalsePositives {
204 self
205 }
206
207 fn find(self) -> Option<u32> {
208 Some(self.foo)
209 }
210
211 fn position(self) -> Option<u32> {
212 Some(self.foo)
213 }
214
215 fn rposition(self) -> Option<u32> {
216 Some(self.foo)
217 }
218
219 fn nth(self, n: usize) -> Option<u32> {
220 Some(self.foo)
221 }
222
223 fn skip(self, _: usize) -> IteratorFalsePositives {
224 self
225 }
226 }
227
228 /// Checks implementation of `FILTER_NEXT` lint
229 fn filter_next() {
230 let v = vec![3, 2, 1, 0, -1, -2, -3];
231
232 // check single-line case
233 let _ = v.iter().filter(|&x| *x < 0).next();
234
235 // check multi-line case
236 let _ = v.iter().filter(|&x| {
237 *x < 0
238 }
239 ).next();
240
241 // check that we don't lint if the caller is not an Iterator
242 let foo = IteratorFalsePositives { foo: 0 };
243 let _ = foo.filter().next();
244 }
245
246 /// Checks implementation of `SEARCH_IS_SOME` lint
247 fn search_is_some() {
248 let v = vec![3, 2, 1, 0, -1, -2, -3];
249
250 // check `find().is_some()`, single-line
251 let _ = v.iter().find(|&x| *x < 0).is_some();
252
253 // check `find().is_some()`, multi-line
254 let _ = v.iter().find(|&x| {
255 *x < 0
256 }
257 ).is_some();
258
259 // check `position().is_some()`, single-line
260 let _ = v.iter().position(|&x| x < 0).is_some();
261
262 // check `position().is_some()`, multi-line
263 let _ = v.iter().position(|&x| {
264 x < 0
265 }
266 ).is_some();
267
268 // check `rposition().is_some()`, single-line
269 let _ = v.iter().rposition(|&x| x < 0).is_some();
270
271 // check `rposition().is_some()`, multi-line
272 let _ = v.iter().rposition(|&x| {
273 x < 0
274 }
275 ).is_some();
276
277 // check that we don't lint if the caller is not an Iterator
278 let foo = IteratorFalsePositives { foo: 0 };
279 let _ = foo.find().is_some();
280 let _ = foo.position().is_some();
281 let _ = foo.rposition().is_some();
282 }
283
284 /// Checks implementation of the `OR_FUN_CALL` lint
285 fn or_fun_call() {
286 struct Foo;
287
288 impl Foo {
289 fn new() -> Foo { Foo }
290 }
291
292 enum Enum {
293 A(i32),
294 }
295
296 const fn make_const(i: i32) -> i32 { i }
297
298 fn make<T>() -> T { unimplemented!(); }
299
300 let with_enum = Some(Enum::A(1));
301 with_enum.unwrap_or(Enum::A(5));
302
303 let with_const_fn = Some(1);
304 with_const_fn.unwrap_or(make_const(5));
305
306 let with_constructor = Some(vec![1]);
307 with_constructor.unwrap_or(make());
308
309 let with_new = Some(vec![1]);
310 with_new.unwrap_or(Vec::new());
311
312 let with_const_args = Some(vec![1]);
313 with_const_args.unwrap_or(Vec::with_capacity(12));
314
315 let with_err : Result<_, ()> = Ok(vec![1]);
316 with_err.unwrap_or(make());
317
318 let with_err_args : Result<_, ()> = Ok(vec![1]);
319 with_err_args.unwrap_or(Vec::with_capacity(12));
320
321 let with_default_trait = Some(1);
322 with_default_trait.unwrap_or(Default::default());
323
324 let with_default_type = Some(1);
325 with_default_type.unwrap_or(u64::default());
326
327 let with_vec = Some(vec![1]);
328 with_vec.unwrap_or(vec![]);
329
330 // FIXME #944: ~|SUGGESTION with_vec.unwrap_or_else(|| vec![]);
331
332 let without_default = Some(Foo);
333 without_default.unwrap_or(Foo::new());
334
335 let mut map = HashMap::<u64, String>::new();
336 map.entry(42).or_insert(String::new());
337
338 let mut btree = BTreeMap::<u64, String>::new();
339 btree.entry(42).or_insert(String::new());
340
341 let stringy = Some(String::from(""));
342 let _ = stringy.unwrap_or("".to_owned());
343 }
344
345 /// Checks implementation of `ITER_NTH` lint
346 fn iter_nth() {
347 let mut some_vec = vec![0, 1, 2, 3];
348 let mut boxed_slice: Box<[u8]> = Box::new([0, 1, 2, 3]);
349 let mut some_vec_deque: VecDeque<_> = some_vec.iter().cloned().collect();
350
351 {
352 // Make sure we lint `.iter()` for relevant types
353 let bad_vec = some_vec.iter().nth(3);
354 let bad_slice = &some_vec[..].iter().nth(3);
355 let bad_boxed_slice = boxed_slice.iter().nth(3);
356 let bad_vec_deque = some_vec_deque.iter().nth(3);
357 }
358
359 {
360 // Make sure we lint `.iter_mut()` for relevant types
361 let bad_vec = some_vec.iter_mut().nth(3);
362 }
363 {
364 let bad_slice = &some_vec[..].iter_mut().nth(3);
365 }
366 {
367 let bad_vec_deque = some_vec_deque.iter_mut().nth(3);
368 }
369
370 // Make sure we don't lint for non-relevant types
371 let false_positive = HasIter;
372 let ok = false_positive.iter().nth(3);
373 let ok_mut = false_positive.iter_mut().nth(3);
374 }
375
376 /// Checks implementation of `ITER_SKIP_NEXT` lint
377 fn iter_skip_next() {
378 let mut some_vec = vec![0, 1, 2, 3];
379 let _ = some_vec.iter().skip(42).next();
380 let _ = some_vec.iter().cycle().skip(42).next();
381 let _ = (1..10).skip(10).next();
382 let _ = &some_vec[..].iter().skip(3).next();
383 let foo = IteratorFalsePositives { foo : 0 };
384 let _ = foo.skip(42).next();
385 let _ = foo.filter().skip(42).next();
386 }
387
388 #[allow(similar_names)]
389 fn main() {
390 let opt = Some(0);
391 let _ = opt.unwrap();
392 }