Auto merge of #110718 - flip1995:clippyup, r=Manishearth

Update Clippy

r? `@Manishearth`

A few days late, I was on a business trip, sorry.

Author: bors

Cargo.lock

@@ -593,9 +593,8 @@ dependencies = [
  "rustc-semver",
  "rustc-workspace-hack",
  "rustc_tools_util",
- "semver",
  "serde",
- "syn 1.0.102",
+ "syn 2.0.8",
  "tempfile",
  "termize",
  "tester",
@@ -746,9 +745,9 @@ dependencies = [
 
 [[package]]
 name = "compiletest_rs"
-version = "0.9.0"
+version = "0.10.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "70489bbb718aea4f92e5f48f2e3b5be670c2051de30e57cb6e5377b4aa08b372"
+checksum = "e2731272cf25196735df1b52ab5bcba22cf9f99455626c4c8dc092bd5f7f66d0"
 dependencies = [
  "diff",
  "filetime",
@@ -973,7 +972,7 @@ version = "0.1.70"
 dependencies = [
  "itertools",
  "quote",
- "syn 1.0.102",
+ "syn 2.0.8",
 ]
 
 [[package]]

src/tools/clippy/CHANGELOG.md

@@ -6,11 +6,126 @@ document.
 
 ## Unreleased / Beta / In Rust Nightly
 
-[7f27e2e7...master](https://github.com/rust-lang/rust-clippy/compare/7f27e2e7...master)
+[149392b0...master](https://github.com/rust-lang/rust-clippy/compare/149392b0...master)
+
+## Rust 1.69
+
+Current stable, released 2023-04-20
+
+[7f27e2e7...149392b0](https://github.com/rust-lang/rust-clippy/compare/7f27e2e7...149392b0)
+
+### New Lints
+
+* [`no_mangle_with_rust_abi`]
+  [#10369](https://github.com/rust-lang/rust-clippy/pull/10369)
+* [`significant_drop_tightening`]
+  [#10163](https://github.com/rust-lang/rust-clippy/pull/10163)
+* [`suspicious_command_arg_space`]
+  [#10317](https://github.com/rust-lang/rust-clippy/pull/10317)
+* [`let_underscore_untyped`]
+  [#10356](https://github.com/rust-lang/rust-clippy/pull/10356)
+* [`question_mark_used`]
+  [#10342](https://github.com/rust-lang/rust-clippy/pull/10342)
+* [`extra_unused_type_parameters`]
+  [#10028](https://github.com/rust-lang/rust-clippy/pull/10028)
+* [`impl_trait_in_params`]
+  [10197](https://github.com/rust-lang/rust-clippy/pull/10197)
+* [`transmute_int_to_non_zero`]
+  [#10360](https://github.com/rust-lang/rust-clippy/pull/10360)
+* [`multiple_unsafe_ops_per_block`]
+  [#10206](https://github.com/rust-lang/rust-clippy/pull/10206)
+
+### Moves and Deprecations
+
+* Moved [`uninlined_format_args`] to `pedantic` (Now allow-by-default)
+  [#10265](https://github.com/rust-lang/rust-clippy/pull/10265)
+* Moved [`unchecked_duration_subtraction`] to `pedantic` (Now allow-by-default)
+  [#10194](https://github.com/rust-lang/rust-clippy/pull/10194)
+
+### Enhancements
+
+* [`arithmetic_side_effects`]: No longer lints, if safe constant values are used.
+  [#10310](https://github.com/rust-lang/rust-clippy/pull/10310)
+* [`needless_lifetimes`]: Now works in local macros
+  [#10257](https://github.com/rust-lang/rust-clippy/pull/10257)
+* [`unused_io_amount`]: Now detects usages of `is_ok` and `is_err`
+  [#10225](https://github.com/rust-lang/rust-clippy/pull/10225)
+* [`missing_docs_in_private_items`]: Added new configuration `missing-docs-in-crate-items` to lint
+  on items visible within the current crate. For example, `pub(crate)` items.
+  [#10303](https://github.com/rust-lang/rust-clippy/pull/10303)
+* [`almost_swapped`]: Now detects almost swaps using `let` statements
+  [#10177](https://github.com/rust-lang/rust-clippy/pull/10177)
+* [`wildcard_enum_match_arm`]: Now lints missing private variants, for local enums
+  [#10250](https://github.com/rust-lang/rust-clippy/pull/10250)
+
+### False Positive Fixes
+
+* [`explicit_auto_deref`]: Now considers projections, when determining if auto deref is applicable
+  [#10386](https://github.com/rust-lang/rust-clippy/pull/10386)
+* [`manual_let_else`]: Now considers side effects of branches, before linting 
+  [#10336](https://github.com/rust-lang/rust-clippy/pull/10336)
+* [`uninlined_format_args`]: No longer lints for arguments with generic parameters
+  [#10343](https://github.com/rust-lang/rust-clippy/pull/10343)
+* [`needless_lifetimes`]: No longer lints signatures in macros, if the lifetime is a metavariable
+  [#10380](https://github.com/rust-lang/rust-clippy/pull/10380)
+* [`len_without_is_empty`]: No longer lints, if `len` as a non-default signature
+  [#10255](https://github.com/rust-lang/rust-clippy/pull/10255)
+* [`unusual_byte_groupings`]: Relaxed the required restrictions for specific sizes, to reduce false
+  positives
+  [#10353](https://github.com/rust-lang/rust-clippy/pull/10353)
+* [`manual_let_else`]: No longer lints `if-else` blocks if they can divergent
+  [#10332](https://github.com/rust-lang/rust-clippy/pull/10332)
+* [`expect_used`], [`unwrap_used`], [`dbg_macro`], [`print_stdout`], [`print_stderr`]: No longer lint
+  in test functions, if `allow-expect-in-tests` is set
+  [#10391](https://github.com/rust-lang/rust-clippy/pull/10391)
+* [`unnecessary_safety_comment`]: No longer lints code inside macros
+  [#10106](https://github.com/rust-lang/rust-clippy/pull/10106)
+* [`never_loop`]: No longer lints, for statements following break statements for outer blocks.
+  [#10311](https://github.com/rust-lang/rust-clippy/pull/10311)
+
+### Suggestion Fixes/Improvements
+
+* [`box_default`]: The suggestion now includes the type for trait objects, when needed
+  [#10382](https://github.com/rust-lang/rust-clippy/pull/10382)
+* [`cast_possible_truncation`]: Now suggests using `try_from` or allowing the lint
+  [#10038](https://github.com/rust-lang/rust-clippy/pull/10038)
+* [`invalid_regex`]: Regex errors for non-literals or regular strings containing escape sequences will
+  now show the complete error
+  [#10231](https://github.com/rust-lang/rust-clippy/pull/10231)
+* [`transmutes_expressible_as_ptr_casts`]: The suggestion now works, if the base type is borrowed
+  [#10193](https://github.com/rust-lang/rust-clippy/pull/10193)
+* [`needless_return`]: Now removes all semicolons on the same line
+  [#10187](https://github.com/rust-lang/rust-clippy/pull/10187)
+* [`suspicious_to_owned`]: The suggestion now shows all options clearly
+  [#10295](https://github.com/rust-lang/rust-clippy/pull/10295)
+* [`bytes_nth`]: Now suggests the correct replacement based on the context
+  [#10361](https://github.com/rust-lang/rust-clippy/pull/10361)
+* [`bool_assert_comparison`]: The suggestion is now machine applicable
+  [#10218](https://github.com/rust-lang/rust-clippy/pull/10218)
+* [`cast_possible_truncation`]: Corrected the lint name in the help message
+  [#10330](https://github.com/rust-lang/rust-clippy/pull/10330)
+* [`needless_return`]: The suggestion now works on if sequences
+  [#10345](https://github.com/rust-lang/rust-clippy/pull/10345)
+* [`needless_lifetimes`]: The suggestion is now machine applicable
+  [#10222](https://github.com/rust-lang/rust-clippy/pull/10222)
+* [`map_entry`]: The suggestion no longer expands macros
+  [#10346](https://github.com/rust-lang/rust-clippy/pull/10346)
+
+### ICE Fixes
+
+* [`needless_pass_by_value`]: Fixed an ICE, caused by how late bounds were handled
+  [#10328](https://github.com/rust-lang/rust-clippy/pull/10328)
+* [`needless_borrow`]: No longer panics on ambiguous projections
+  [#10403](https://github.com/rust-lang/rust-clippy/pull/10403)
+
+### Documentation Improvements
+
+* All configurations are now documented in the Clippy Book
+  [#10199](https://github.com/rust-lang/rust-clippy/pull/10199)
 
 ## Rust 1.68
 
-Current stable, released 2023-03-09
+Released 2023-03-09
 
 [d822110d...7f27e2e7](https://github.com/rust-lang/rust-clippy/compare/d822110d...7f27e2e7)
 
@@ -4615,6 +4730,7 @@ Released 2018-09-13
 [`invisible_characters`]: https://rust-lang.github.io/rust-clippy/master/index.html#invisible_characters
 [`is_digit_ascii_radix`]: https://rust-lang.github.io/rust-clippy/master/index.html#is_digit_ascii_radix
 [`items_after_statements`]: https://rust-lang.github.io/rust-clippy/master/index.html#items_after_statements
+[`items_after_test_module`]: https://rust-lang.github.io/rust-clippy/master/index.html#items_after_test_module
 [`iter_cloned_collect`]: https://rust-lang.github.io/rust-clippy/master/index.html#iter_cloned_collect
 [`iter_count`]: https://rust-lang.github.io/rust-clippy/master/index.html#iter_count
 [`iter_kv_map`]: https://rust-lang.github.io/rust-clippy/master/index.html#iter_kv_map

src/tools/clippy/Cargo.toml

@@ -22,13 +22,12 @@ path = "src/driver.rs"
 
 [dependencies]
 clippy_lints = { path = "clippy_lints" }
-semver = "1.0"
 rustc_tools_util = "0.3.0"
 tempfile = { version = "3.2", optional = true }
 termize = "0.1"
 
 [dev-dependencies]
-compiletest_rs = { version = "0.9", features = ["tmp"] }
+compiletest_rs = { version = "0.10", features = ["tmp"] }
 tester = "0.9"
 regex = "1.5"
 toml = "0.5"
@@ -49,7 +48,7 @@ if_chain = "1.0"
 itertools = "0.10.1"
 quote = "1.0"
 serde = { version = "1.0.125", features = ["derive"] }
-syn = { version = "1.0", features = ["full"] }
+syn = { version = "2.0", features = ["full"] }
 futures = "0.3"
 parking_lot = "0.12"
 tokio = { version = "1", features = ["io-util"] }

src/tools/clippy/book/src/SUMMARY.md

@@ -13,7 +13,9 @@
 - [Development](development/README.md)
     - [Basics](development/basics.md)
     - [Adding Lints](development/adding_lints.md)
+    - [Lint Passes](development/lint_passes.md)
     - [Type Checking](development/type_checking.md)
+    - [Macro Expansions](development/macro_expansions.md)
     - [Common Tools](development/common_tools_writing_lints.md)
     - [Infrastructure](development/infrastructure/README.md)
         - [Syncing changes between Clippy and rust-lang/rust](development/infrastructure/sync.md)

src/tools/clippy/book/src/development/README.md

@@ -13,6 +13,24 @@ If this is your first time contributing to Clippy, you should first read the
 [Basics docs](basics.md). This will explain the basics on how to get the source
 code and how to compile and test the code.
 
+## Additional Readings for Beginners
+
+If a dear reader of this documentation has never taken a class on compilers
+and interpreters, it might be confusing as to why AST level deals with only
+the language's syntax. And some readers might not even understand what lexing,
+parsing, and AST mean.
+
+This documentation serves by no means as a crash course on compilers or language design.
+And for details specifically related to Rust, the [Rustc Development Guide][rustc_dev_guide]
+is a far better choice to peruse.
+
+The [Syntax and AST][ast] chapter and the [High-Level IR][hir] chapter are
+great introduction to the concepts mentioned in this chapter.
+
+Some readers might also find the [introductory chapter][map_of_territory] of
+Robert Nystrom's _Crafting Interpreters_ a helpful overview of compiled and
+interpreted languages before jumping back to the Rustc guide.
+
 ## Writing code
 
 If you have done the basic setup, it's time to start hacking.
@@ -37,6 +55,10 @@ book](../lints.md).
 > - Triage procedure
 > - Bors and Homu
 
+[ast]: https://rustc-dev-guide.rust-lang.org/syntax-intro.html
+[hir]: https://rustc-dev-guide.rust-lang.org/hir.html
+[rustc_dev_guide]: https://rustc-dev-guide.rust-lang.org/
+[map_of_territory]: https://craftinginterpreters.com/a-map-of-the-territory.html
 [clippy_rfc]: https://github.com/rust-lang/rfcs/blob/master/text/2476-clippy-uno.md
 [rfc_stability]: https://github.com/rust-lang/rfcs/blob/master/text/2476-clippy-uno.md#stability-guarantees
 [rfc_lint_cats]: https://github.com/rust-lang/rfcs/blob/master/text/2476-clippy-uno.md#lint-audit-and-categories

src/tools/clippy/book/src/development/adding_lints.md

@@ -164,7 +164,7 @@ The process of generating the `.stderr` file is the same, and prepending the
 ## Rustfix tests
 
 If the lint you are working on is making use of structured suggestions, the test
-file should include a `// run-rustfix` comment at the top. This will
+file should include a `//@run-rustfix` comment at the top. This will
 additionally run [rustfix] for that test. Rustfix will apply the suggestions
 from the lint to the code of the test file and compare that to the contents of a
 `.fixed` file.

src/tools/clippy/book/src/development/lint_passes.md

@@ -0,0 +1,114 @@
+# Lint passes
+
+Before working on the logic of a new lint, there is an important decision
+that every Clippy developer must make: to use
+[`EarlyLintPass`][early_lint_pass] or [`LateLintPass`][late_lint_pass].
+
+In short, the `LateLintPass` has access to type and symbol information while the
+`EarlyLintPass` doesn't. If you don't need access to type information, use the
+`EarlyLintPass`.
+
+Let us expand on these two traits more below.
+
+## `EarlyLintPass`
+
+If you examine the documentation on [`EarlyLintPass`][early_lint_pass] closely,
+you'll see that every method defined for this trait utilizes a
+[`EarlyContext`][early_context]. In `EarlyContext`'s documentation, it states:
+
+> Context for lint checking of the AST, after expansion, before lowering to HIR.
+
+Voilà. `EarlyLintPass` works only on the Abstract Syntax Tree (AST) level.
+And AST is generated during the [lexing and parsing][lexing_and_parsing] phase
+of code compilation. Therefore, it doesn't know what a symbol means or information about types, and it should
+be our trait choice for a new lint if the lint only deals with syntax-related issues.
+
+While linting speed has not been a concern for Clippy,
+the `EarlyLintPass` is faster, and it should be your choice
+if you know for sure a lint does not need type information.
+
+As a reminder, run the following command to generate boilerplate for lints
+that use `EarlyLintPass`:
+
+```sh
+$ cargo dev new_lint --name=<your_new_lint> --pass=early --category=<your_category_choice>
+```
+
+### Example for `EarlyLintPass`
+
+Take a look at the following code:
+
+```rust
+let x = OurUndefinedType;
+x.non_existing_method();
+```
+
+From the AST perspective, both lines are "grammatically" correct.
+The assignment uses a `let` and ends with a semicolon. The invocation
+of a method looks fine, too. As programmers, we might raise a few
+questions already, but the parser is okay with it. This is what we
+mean when we say `EarlyLintPass` deals with only syntax on the AST level.
+
+Alternatively, think of the `foo_functions` lint we mentioned in
+define new lints chapter.
+
+We want the `foo_functions` lint to detect functions with `foo` as their name.
+Writing a lint that only checks for the name of a function means that we only
+work with the AST and don't have to access the type system at all (the type system is where
+`LateLintPass` comes into the picture).
+
+## `LateLintPass`
+
+In contrast to `EarlyLintPass`, `LateLintPass` contains type information.
+
+If you examine the documentation on [`LateLintPass`][late_lint_pass] closely,
+you see that every method defined in this trait utilizes a
+[`LateContext`][late_context].
+
+In `LateContext`'s documentation we will find methods that
+deal with type-checking, which do not exist in `EarlyContext`, such as:
+
+- [`maybe_typeck_results`](https://doc.rust-lang.org/nightly/nightly-rustc/rustc_lint/context/struct.LateContext.html#method.maybe_typeck_results)
+- [`typeck_results`](https://doc.rust-lang.org/nightly/nightly-rustc/rustc_lint/context/struct.LateContext.html#method.typeck_results)
+
+### Example for `LateLintPass`
+
+Let us take a look with the following example:
+
+```rust
+let x = OurUndefinedType;
+x.non_existing_method();
+```
+
+These two lines of code are syntactically correct code from the perspective
+of the AST. We have an assignment and invoke a method on the variable that
+is of a type. Grammatically, everything is in order for the parser.
+
+However, going down a level and looking at the type information,
+the compiler will notice that both `OurUndefinedType` and `non_existing_method()`
+**are undefined**.
+
+As Clippy developers, to access such type information, we must implement
+`LateLintPass` on our lint.
+When you browse through Clippy's lints, you will notice that almost every lint
+is implemented in a `LateLintPass`, specifically because we often need to check
+not only for syntactic issues but also type information.
+
+Another limitation of the `EarlyLintPass` is that the nodes are only identified
+by their position in the AST. This means that you can't just get an `id` and
+request a certain node. For most lints that is fine, but we have some lints
+that require the inspection of other nodes, which is easier at the HIR level.
+In these cases, `LateLintPass` is the better choice.
+
+As a reminder, run the following command to generate boilerplate for lints
+that use `LateLintPass`:
+
+```sh
+$ cargo dev new_lint --name=<your_new_lint> --pass=late --category=<your_category_choice>
+```
+
+[early_context]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_lint/context/struct.EarlyContext.html
+[early_lint_pass]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_lint/trait.EarlyLintPass.html
+[late_context]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_lint/context/struct.LateContext.html
+[late_lint_pass]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_lint/trait.LateLintPass.html
+[lexing_and_parsing]: https://rustc-dev-guide.rust-lang.org/overview.html#lexing-and-parsing