restriction lint for `std::process::exit`
Addition to #4655 - adds the lint checking for `std::process::exit`
changelog: add restriction lint for `std::process::exit`
build: improve script and travis config
* fix a diff failure on windows
See https://travis-ci.com/rust-lang/rust-clippy/jobs/245971932#L1625
for an example.
* use cmp instead of diff > /dev/null
* clone single branch instead of clone then checking out
* do not decrypt key if have no diff change
changelog: none
Add lint for debug_assert_with_mut_call
closes#1526
**What does not work:**
* detecting a mut call in the format string itself, e.g. `debug_assert!(false, "{}", vec![1].pop())`
* detecting `*mut T` usage (pointer)
---
changelog: add new lint `debug_assert_with_mut_call`
Fix suggestion of `explicit_counter_loop`
changelog: In the suggestion of `explicit_counter_loop`, if the `for` loop argument doesn't implement `Iterator`, then we suggest `x.into_iter().enumerate()` (or `x.iter{_mut}()` as appropriate). Also, the span of the suggestion has been corrected.
Fixes#4678
This lint will complain when you put a mutable function/method call
inside a `debug_assert` macro, because it will not be executed in
release mode, therefore it will change the execution flow, which is not
wanted.
`must_use_unit` lints unit-returning functions with a `#[must_use]`
attribute, suggesting to remove it.
`double_must_use` lints functions with a plain `#[must_use]`
attribute, but which return a type which is already `#[must_use]`,
so the attribute has no benefit.
`must_use_candidate` is a pedantic lint that lints functions and
methods that return some non-unit type that is not already
`#[must_use]` and suggests to add the annotation.
Lints when, on the RHS of a BinOp, there is a UnOp without a space
before the operator but with a space after (e.g. foo >- 1).
Signed-off-by: Nikos Filippakis <nikolaos.filippakis@cern.ch>
