* [*clippy-service*](#link-with-clippy-service)
* [License](#license)
+## Usage
+
+As a general rule clippy will only work with the *latest* Rust nightly for now.
+
+### As a Compiler Plugin
+
+Since stable Rust is backwards compatible, you should be able to
+compile your stable programs with nightly Rust with clippy plugged in to
+circumvent this.
+
+Add in your `Cargo.toml`:
+
+```toml
+[dependencies]
+clippy = "*"
+```
+
+You then need to add `#![feature(plugin)]` and `#![plugin(clippy)]` to the top
+of your crate entry point (`main.rs` or `lib.rs`).
+
+Sample `main.rs`:
+
+```rust
+#![feature(plugin)]
+
+#![plugin(clippy)]
+
+
+fn main(){
+ let x = Some(1u8);
+ match x {
+ Some(y) => println!("{:?}", y),
+ _ => ()
+ }
+}
+```
+
+Produces this warning:
+
+```terminal
+src/main.rs:8:5: 11:6 warning: you seem to be trying to use match for destructuring a single type. Consider using `if let`, #[warn(single_match)] on by default
+src/main.rs:8 match x {
+src/main.rs:9 Some(y) => println!("{:?}", y),
+src/main.rs:10 _ => ()
+src/main.rs:11 }
+src/main.rs:8:5: 11:6 help: Try
+if let Some(y) = x { println!("{:?}", y) }
+```
+
+### As a cargo subcommand (`cargo clippy`)
+
+An alternate way to use clippy is by installing clippy through cargo as a cargo
+subcommand.
+
+```terminal
+cargo install clippy
+```
+
+Now you can run clippy by invoking `cargo clippy`, or
+`rustup run nightly cargo clippy` directly from a directory that is usually
+compiled with stable.
+
+In case you are not using rustup, you need to set the environment flag
+`SYSROOT` during installation so clippy knows where to find `librustc` and
+similar crates.
+
+```terminal
+SYSROOT=/path/to/rustc/sysroot cargo install clippy
+```
+
+### Running clippy from the command line without installing
+
+To have cargo compile your crate with clippy without needing `#![plugin(clippy)]`
+in your code, you can use:
+
+```terminal
+cargo rustc -- -L /path/to/clippy_so -Z extra-plugins=clippy
+```
+
+*[Note](https://github.com/Manishearth/rust-clippy/wiki#a-word-of-warning):*
+Be sure that clippy was compiled with the same version of rustc that cargo invokes here!
+
+### Optional dependency
+
+If you want to make clippy an optional dependency, you can do the following:
+
+In your `Cargo.toml`:
+
+```toml
+[dependencies]
+clippy = {version = "*", optional = true}
+
+[features]
+default = []
+```
+
+And, in your `main.rs` or `lib.rs`:
+
+```rust
+#![cfg_attr(feature="clippy", feature(plugin))]
+
+#![cfg_attr(feature="clippy", plugin(clippy))]
+```
+
+Then build by enabling the feature: `cargo build --features "clippy"`
+
+Instead of adding the `cfg_attr` attributes you can also run clippy on demand:
+`cargo rustc --features clippy -- -Z no-trans -Z extra-plugins=clippy`
+(the `-Z no trans`, while not neccessary, will stop the compilation process after
+typechecking (and lints) have completed, which can significantly reduce the runtime).
+
+## Configuration
+
+Some lints can be configured in a `clippy.toml` file. It contains basic `variable = value` mapping eg.
+
+```toml
+blacklisted-names = ["toto", "tata", "titi"]
+cyclomatic-complexity-threshold = 30
+```
+
+See the wiki for more information about which lints can be configured and the
+meaning of the variables.
+
+You can also specify the path to the configuration file with:
+
+```rust
+#![plugin(clippy(conf_file="path/to/clippy's/configuration"))]
+```
+
+To deactivate the “for further information visit *wiki-link*” message you can
+define the `CLIPPY_DISABLE_WIKI_LINKS` environment variable.
+
+### Allowing/denying lints
+
+You can add options to `allow`/`warn`/`deny`:
+
+* the whole set of `Warn` lints using the `clippy` lint group (`#![deny(clippy)]`)
+
+* all lints using both the `clippy` and `clippy_pedantic` lint groups (`#![deny(clippy)]`,
+ `#![deny(clippy_pedantic)]`). Note that `clippy_pedantic` contains some very aggressive
+ lints prone to false positives.
+
+* only some lints (`#![deny(single_match, box_vec)]`, etc)
+
+* `allow`/`warn`/`deny` can be limited to a single function or module using `#[allow(...)]`, etc
+
+Note: `deny` produces errors instead of warnings.
+
+## Link with clippy service
+
+`clippy-service` is a rust web initiative providing `rust-clippy` as a web service.
+
+Both projects are independent and maintained by different people
+(even if some `clippy-service`'s contributions are authored by some `rust-clippy` members).
+
+You can check out this great service at [clippy.bashy.io](https://clippy.bashy.io/).
+
## Lints
-There are 162 lints included in this crate:
+There are 171 lints included in this crate:
name | default | triggers on
---------------------------------------------------------------------------------------------------------------------|---------|----------------------------------------------------------------------------------------------------------------------------------
[bool_comparison](https://github.com/Manishearth/rust-clippy/wiki#bool_comparison) | warn | comparing a variable to a boolean, e.g. `if x == true`
[box_vec](https://github.com/Manishearth/rust-clippy/wiki#box_vec) | warn | usage of `Box<Vec<T>>`, vector elements are already on the heap
[boxed_local](https://github.com/Manishearth/rust-clippy/wiki#boxed_local) | warn | using `Box<T>` where unnecessary
+[builtin_type_shadow](https://github.com/Manishearth/rust-clippy/wiki#builtin_type_shadow) | warn | shadowing a builtin type
[cast_possible_truncation](https://github.com/Manishearth/rust-clippy/wiki#cast_possible_truncation) | allow | casts that may cause truncation of the value, e.g `x as u8` where `x: u32`, or `x as i32` where `x: f32`
[cast_possible_wrap](https://github.com/Manishearth/rust-clippy/wiki#cast_possible_wrap) | allow | casts that may cause wrapping around the value, e.g `x as i32` where `x: u32` and `x > i32::MAX`
[cast_precision_loss](https://github.com/Manishearth/rust-clippy/wiki#cast_precision_loss) | allow | casts that cause loss of precision, e.g `x as f32` where `x: u64`
[clone_double_ref](https://github.com/Manishearth/rust-clippy/wiki#clone_double_ref) | warn | using `clone` on `&&T`
[clone_on_copy](https://github.com/Manishearth/rust-clippy/wiki#clone_on_copy) | warn | using `clone` on a `Copy` type
[cmp_nan](https://github.com/Manishearth/rust-clippy/wiki#cmp_nan) | deny | comparisons to NAN, which will always return false, probably not intended
+[cmp_null](https://github.com/Manishearth/rust-clippy/wiki#cmp_null) | warn | comparing a pointer to a null pointer, suggesting to use `.is_null()` instead.
[cmp_owned](https://github.com/Manishearth/rust-clippy/wiki#cmp_owned) | warn | creating owned instances for comparing with others, e.g. `x == "foo".to_string()`
[collapsible_if](https://github.com/Manishearth/rust-clippy/wiki#collapsible_if) | warn | `if`s that can be collapsed (e.g. `if x { if y { ... } }` and `else { if x { ... } }`)
[crosspointer_transmute](https://github.com/Manishearth/rust-clippy/wiki#crosspointer_transmute) | warn | transmutes that have to or from types that are a pointer to the other
[cyclomatic_complexity](https://github.com/Manishearth/rust-clippy/wiki#cyclomatic_complexity) | warn | functions that should be split up into multiple functions
[deprecated_semver](https://github.com/Manishearth/rust-clippy/wiki#deprecated_semver) | warn | use of `#[deprecated(since = "x")]` where x is not semver
[derive_hash_xor_eq](https://github.com/Manishearth/rust-clippy/wiki#derive_hash_xor_eq) | warn | deriving `Hash` but implementing `PartialEq` explicitly
+[diverging_sub_expression](https://github.com/Manishearth/rust-clippy/wiki#diverging_sub_expression) | warn | whether an expression contains a diverging sub expression
[doc_markdown](https://github.com/Manishearth/rust-clippy/wiki#doc_markdown) | warn | presence of `_`, `::` or camel-case outside backticks in documentation
[double_neg](https://github.com/Manishearth/rust-clippy/wiki#double_neg) | warn | `--x`, which is a double negation of `x` and not a pre-decrement as in C/C++
[drop_ref](https://github.com/Manishearth/rust-clippy/wiki#drop_ref) | warn | calls to `std::mem::drop` with a reference instead of an owned value
[enum_glob_use](https://github.com/Manishearth/rust-clippy/wiki#enum_glob_use) | allow | use items that import all variants of an enum
[enum_variant_names](https://github.com/Manishearth/rust-clippy/wiki#enum_variant_names) | warn | enums where all variants share a prefix/postfix
[eq_op](https://github.com/Manishearth/rust-clippy/wiki#eq_op) | warn | equal operands on both sides of a comparison or bitwise combination (e.g. `x == x`)
+[eval_order_dependence](https://github.com/Manishearth/rust-clippy/wiki#eval_order_dependence) | warn | whether a variable read occurs before a write depends on sub-expression evaluation order
[expl_impl_clone_on_copy](https://github.com/Manishearth/rust-clippy/wiki#expl_impl_clone_on_copy) | warn | implementing `Clone` explicitly on `Copy` types
[explicit_counter_loop](https://github.com/Manishearth/rust-clippy/wiki#explicit_counter_loop) | warn | for-looping with an explicit counter when `_.enumerate()` would do
[explicit_iter_loop](https://github.com/Manishearth/rust-clippy/wiki#explicit_iter_loop) | warn | for-looping over `_.iter()` or `_.iter_mut()` when `&_` or `&mut _` would do
[items_after_statements](https://github.com/Manishearth/rust-clippy/wiki#items_after_statements) | allow | blocks where an item comes after a statement
[iter_next_loop](https://github.com/Manishearth/rust-clippy/wiki#iter_next_loop) | warn | for-looping over `_.next()` which is probably not intended
[iter_nth](https://github.com/Manishearth/rust-clippy/wiki#iter_nth) | warn | using `.iter().nth()` on a standard library type with O(1) element access
-[len_without_is_empty](https://github.com/Manishearth/rust-clippy/wiki#len_without_is_empty) | warn | traits and impls that have `.len()` but not `.is_empty()`
+[len_without_is_empty](https://github.com/Manishearth/rust-clippy/wiki#len_without_is_empty) | warn | traits or impls with a public `len` method but no corresponding `is_empty` method
[len_zero](https://github.com/Manishearth/rust-clippy/wiki#len_zero) | warn | checking `.len() == 0` or `.len() > 0` (or similar) when `.is_empty()` could be used instead
[let_and_return](https://github.com/Manishearth/rust-clippy/wiki#let_and_return) | warn | creating a let-binding and then immediately returning it like `let x = expr; x` at the end of a block
[let_unit_value](https://github.com/Manishearth/rust-clippy/wiki#let_unit_value) | warn | creating a let binding to a value of unit type, which usually can't be used afterwards
[mem_forget](https://github.com/Manishearth/rust-clippy/wiki#mem_forget) | allow | `mem::forget` usage on `Drop` types, likely to cause memory leaks
[min_max](https://github.com/Manishearth/rust-clippy/wiki#min_max) | warn | `min(_, max(_, _))` (or vice versa) with bounds clamping the result to a constant
[misrefactored_assign_op](https://github.com/Manishearth/rust-clippy/wiki#misrefactored_assign_op) | warn | having a variable on both sides of an assign op
+[missing_docs_in_private_items](https://github.com/Manishearth/rust-clippy/wiki#missing_docs_in_private_items) | allow | detects missing documentation for public and private members
[mixed_case_hex_literals](https://github.com/Manishearth/rust-clippy/wiki#mixed_case_hex_literals) | warn | hex literals whose letter digits are not consistently upper- or lowercased
+[module_inception](https://github.com/Manishearth/rust-clippy/wiki#module_inception) | warn | modules that have the same name as their parent module
[modulo_one](https://github.com/Manishearth/rust-clippy/wiki#modulo_one) | warn | taking a number modulo 1, which always returns 0
[mut_mut](https://github.com/Manishearth/rust-clippy/wiki#mut_mut) | allow | usage of double-mut refs, e.g. `&mut &mut ...`
[mutex_atomic](https://github.com/Manishearth/rust-clippy/wiki#mutex_atomic) | warn | using a mutex where an atomic value could be used instead
[panic_params](https://github.com/Manishearth/rust-clippy/wiki#panic_params) | warn | missing parameters in `panic!` calls
[precedence](https://github.com/Manishearth/rust-clippy/wiki#precedence) | warn | operations where precedence may be unclear
[print_stdout](https://github.com/Manishearth/rust-clippy/wiki#print_stdout) | allow | printing on stdout
-[ptr_arg](https://github.com/Manishearth/rust-clippy/wiki#ptr_arg) | warn | arguments of the type `&Vec<...>` (instead of `&[...]`) or `&String` (instead of `&str`)
+[print_with_newline](https://github.com/Manishearth/rust-clippy/wiki#print_with_newline) | warn | using `print!()` with a format string that ends in a newline
+[ptr_arg](https://github.com/Manishearth/rust-clippy/wiki#ptr_arg) | warn | fn arguments of the type `&Vec<...>` or `&String`, suggesting to use `&[...]` or `&str` instead, respectively
[range_step_by_zero](https://github.com/Manishearth/rust-clippy/wiki#range_step_by_zero) | warn | using `Range::step_by(0)`, which produces an infinite iterator
[range_zip_with_len](https://github.com/Manishearth/rust-clippy/wiki#range_zip_with_len) | warn | zipping iterator with a range when `enumerate()` would do
[redundant_closure](https://github.com/Manishearth/rust-clippy/wiki#redundant_closure) | warn | redundant closures, i.e. `|a| foo(a)` (which can be written as just `foo`)
[unused_lifetimes](https://github.com/Manishearth/rust-clippy/wiki#unused_lifetimes) | warn | unused lifetimes in function definitions
[use_debug](https://github.com/Manishearth/rust-clippy/wiki#use_debug) | allow | use of `Debug`-based formatting
[used_underscore_binding](https://github.com/Manishearth/rust-clippy/wiki#used_underscore_binding) | allow | using a binding which is prefixed with an underscore
+[useless_attribute](https://github.com/Manishearth/rust-clippy/wiki#useless_attribute) | warn | use of lint attributes on `extern crate` items
[useless_format](https://github.com/Manishearth/rust-clippy/wiki#useless_format) | warn | useless use of `format!`
[useless_let_if_seq](https://github.com/Manishearth/rust-clippy/wiki#useless_let_if_seq) | warn | unidiomatic `let mut` declaration followed by initialization in `if`
[useless_transmute](https://github.com/Manishearth/rust-clippy/wiki#useless_transmute) | warn | transmutes that have the same to and from types or could be a cast/coercion
[wrong_self_convention](https://github.com/Manishearth/rust-clippy/wiki#wrong_self_convention) | warn | defining a method named with an established prefix (like "into_") that takes `self` with the wrong convention
[wrong_transmute](https://github.com/Manishearth/rust-clippy/wiki#wrong_transmute) | warn | transmutes that are confusing at best, undefined behaviour at worst and always useless
[zero_divided_by_zero](https://github.com/Manishearth/rust-clippy/wiki#zero_divided_by_zero) | warn | usage of `0.0 / 0.0` to obtain NaN instead of std::f32::NaN or std::f64::NaN
+[zero_prefixed_literal](https://github.com/Manishearth/rust-clippy/wiki#zero_prefixed_literal) | warn | integer literals starting with `0`
[zero_width_space](https://github.com/Manishearth/rust-clippy/wiki#zero_width_space) | deny | using a zero-width space in a string literal, which is confusing
More to come, please [file an issue](https://github.com/Manishearth/rust-clippy/issues) if you have ideas!
-## Usage
-
-As a general rule clippy will only work with the *latest* Rust nightly for now.
-
-### As a Compiler Plugin
-
-Since stable Rust is backwards compatible, you should be able to
-compile your stable programs with nightly Rust with clippy plugged in to
-circumvent this.
-
-Add in your `Cargo.toml`:
-
-```toml
-[dependencies]
-clippy = "*"
-```
-
-You then need to add `#![feature(plugin)]` and `#![plugin(clippy)]` to the top
-of your crate entry point (`main.rs` or `lib.rs`).
-
-Sample `main.rs`:
-
-```rust
-#![feature(plugin)]
-
-#![plugin(clippy)]
-
-
-fn main(){
- let x = Some(1u8);
- match x {
- Some(y) => println!("{:?}", y),
- _ => ()
- }
-}
-```
-
-Produces this warning:
-
-```terminal
-src/main.rs:8:5: 11:6 warning: you seem to be trying to use match for destructuring a single type. Consider using `if let`, #[warn(single_match)] on by default
-src/main.rs:8 match x {
-src/main.rs:9 Some(y) => println!("{:?}", y),
-src/main.rs:10 _ => ()
-src/main.rs:11 }
-src/main.rs:8:5: 11:6 help: Try
-if let Some(y) = x { println!("{:?}", y) }
-```
-
-### As a cargo subcommand (`cargo clippy`)
-
-An alternate way to use clippy is by installing clippy through cargo as a cargo
-subcommand.
-
-```terminal
-cargo install clippy
-```
-
-Now you can run clippy by invoking `cargo clippy`, or
-`rustup run nightly cargo clippy` directly from a directory that is usually
-compiled with stable.
-
-In case you are not using rustup, you need to set the environment flag
-`SYSROOT` during installation so clippy knows where to find `librustc` and
-similar crates.
-
-```terminal
-SYSROOT=/path/to/rustc/sysroot cargo install clippy
-```
-
-### Running clippy from the command line without installing
-
-To have cargo compile your crate with clippy without needing `#![plugin(clippy)]`
-in your code, you can use:
-
-```terminal
-cargo rustc -- -L /path/to/clippy_so -Z extra-plugins=clippy
-```
-
-*[Note](https://github.com/Manishearth/rust-clippy/wiki#a-word-of-warning):*
-Be sure that clippy was compiled with the same version of rustc that cargo invokes here!
-
-### Optional dependency
-
-If you want to make clippy an optional dependency, you can do the following:
-
-In your `Cargo.toml`:
-
-```toml
-[dependencies]
-clippy = {version = "*", optional = true}
-
-[features]
-default = []
-```
-
-And, in your `main.rs` or `lib.rs`:
-
-```rust
-#![cfg_attr(feature="clippy", feature(plugin))]
-
-#![cfg_attr(feature="clippy", plugin(clippy))]
-```
-
-Then build by enabling the feature: `cargo build --features "clippy"`
-
-Instead of adding the `cfg_attr` attributes you can also run clippy on demand:
-`cargo rustc --features clippy -- -Z no-trans -Z extra-plugins=clippy`
-(the `-Z no trans`, while not neccessary, will stop the compilation process after
-typechecking (and lints) have completed, which can significantly reduce the runtime).
-
-## Configuration
-
-Some lints can be configured in a `clippy.toml` file. It contains basic `variable = value` mapping eg.
-
-```toml
-blacklisted-names = ["toto", "tata", "titi"]
-cyclomatic-complexity-threshold = 30
-```
-
-See the wiki for more information about which lints can be configured and the
-meaning of the variables.
-
-You can also specify the path to the configuration file with:
-
-```rust
-#![plugin(clippy(conf_file="path/to/clippy's/configuration"))]
-```
-
-To deactivate the “for further information visit *wiki-link*” message you can
-define the `CLIPPY_DISABLE_WIKI_LINKS` environment variable.
-
-### Allowing/denying lints
-
-You can add options to `allow`/`warn`/`deny`:
-
-* the whole set of `Warn` lints using the `clippy` lint group (`#![deny(clippy)]`)
-
-* all lints using both the `clippy` and `clippy_pedantic` lint groups (`#![deny(clippy)]`,
- `#![deny(clippy_pedantic)]`). Note that `clippy_pedantic` contains some very aggressive
- lints prone to false positives.
-
-* only some lints (`#![deny(single_match, box_vec)]`, etc)
-
-* `allow`/`warn`/`deny` can be limited to a single function or module using `#[allow(...)]`, etc
-
-Note: `deny` produces errors instead of warnings.
-
-## Link with clippy service
-
-`clippy-service` is a rust web initiative providing `rust-clippy` as a web service.
-
-Both projects are independent and maintained by different people
-(even if some `clippy-service`'s contributions are authored by some `rust-clippy` members).
-
-You can check out this great service at [clippy.bashy.io](https://clippy.bashy.io/).
-
## License
Licensed under [MPL](https://www.mozilla.org/MPL/2.0/).
projects / rust.git / blobdiff