changelog: [`unwrap_used`, `expect_used`]: lint even when the receiver
is a macro expansion result
This also paves the way for expanding more method call lints to expanded
receivers or arguments.
Fixesrust-lang/rust-clippy#13455
This lint detects inefficient or useless `{std,core}::mem::swap()` calls
such as:
```rust
// Should be `a = temp();`
swap(&mut a, &mut temp());
// Should be `*b = temp();`
swap(b, &mut temp());
// Should be `temp1(); temp2();` if we want to keep the side effects
swap(&mut temp1(), &mut temp2());
```
It also takes care of using a form appropriate for a `()` context if
`swap()` is part of a larger expression (don't ask me why this wouldn't
happen, I have no idea), by suggesting `{ x = y; }` (statement in block)
or `{std,core}::mem::drop((temp1(), temp2())`.
changelog: [`swap_with_temporary`]: new lint
Close#1968
These method chains can be expressed concisely with `if` / `else`.
changelog: [`obfuscated_if_else`]: support `then().unwrap_or_default()`
and `then_some().unwrap_or_default()`
Until `if let` chains are stabilized, we do not collapse them together
or with other `if` expressions unless the `let_chains` feature is
enabled. This is the case for example in Clippy sources.
This was made possible by converting the `collapsible_if` to a late lint
to get access to the set of enabled features. This allows this PR to
supersede #14455 and no longer require an additional configuration
option.
The three commits are, in order:
- a conversion of the existing early lint to a late lint, with no new
feature or tests changes
- the addition of the `let_chains` feature detection and action, and
tests
- the application of the enhanced lint to Clippy sources (136 files
modified)
changelog: [`collapsible_if`]: recognize the rust compiler `let_chains`
feature
r? @flip1995
Sometimes, in doc comments, there are 3 spaces + 1 instead of 4 spaces + 1.
To make it coherent with the rest of the clippy codebase, I `fd -t f -X sed -E -i 's,/// (\S),/// \1,g'` and manually verified and fixed the relevant part of code that had bad indentation.
Continuing the work from #137350.
Removes the unused methods: `expect_variant`, `expect_field`,
`expect_foreign_item`.
Every method gains a `hir_` prefix.
These method chains can be expressed concisely with `if`/`else`.
changelog: [`obfuscated_if_else`]: support `then().unwrap_or_else()` and
`then_some().unwrap_or_else()`
The end goal is to eliminate `Map` altogether.
I added a `hir_` prefix to all of them, that seemed simplest. The
exceptions are `module_items` which became `hir_module_free_items` because
there was already a `hir_module_items`, and `items` which became
`hir_free_items` for consistency with `hir_module_free_items`.
By default, do not lint `.unwrap()` and `.expect(…)` in always const
contexts, as a failure would be detected at compile time anyway.
New options `allow_expect_in_consts` and `allow_unwrap_in_consts`,
defaulting to `true`, can be turned unset to still lint in always const
contexts.
While extending the `option_map_or_err_ok` lint (warn by default,
"style") to recognize η-expanded forms of `Ok`, as in
```rust
// Should suggest `opt.ok_or("foobar")`
let _ = opt.map_or(Err("foobar"), |x| Ok(x));
```
I discovered that the `manual_ok_or` lint (allow by default, "pedantic")
already covered exactly the cases handled by `option_map_or_err_ok`,
including the one I was adding. Apparently, `option_map_or_err_ok` was
added without realizing that the lint already existed under the
`manual_ok_or` name. As a matter of fact, artifacts of this second lint
were even present in the first lint `stderr` file and went unnoticed for
more than a year.
This PR:
- deprecates `option_map_or_err_ok` with a message saying to use
`manual_ok_or`
- moves `manual_ok_or` from "pedantic" to "style" (the category in which
`option_map_or_err_ok` was)
In addition, I think that this lint, which is short, machine applicable,
and leads to shorter and clearer code with less arguments (`Ok`
disappears) and the removal of one level of call (`Err(x)` is replaced
by `x`), is a reason by itself to be in "style".
changelog: [`option_map_or_err_ok` and `manual_ok_or`]: move
`manual_ok_or` from "pedantic" to "style", and deprecate the redundant
style lint `option_map_or_err_ok`.
