rustdoc
provides lints to help you writing and testing your documentation. You
can use them like any other lints by doing this:
#![allow(missing_docs)] // allowing the lint, no message
#![warn(missing_docs)] // warn if there is missing docs
#![deny(missing_docs)] // rustdoc will fail if there is missing docs
Here is the list of the lints provided by rustdoc
:
This lint warns by default. This lint detects when an intra-doc link fails to get resolved. For example:
/// I want to link to [`Nonexistent`] but it doesn't exist!
pub fn foo() {}
You'll get a warning saying:
warning: unresolved link to `Nonexistent`
--> test.rs:1:24
|
1 | /// I want to link to [`Nonexistent`] but it doesn't exist!
| ^^^^^^^^^^^^^ no item named `Nonexistent` in `test`
It will also warn when there is an ambiguity and suggest how to disambiguate:
/// [`Foo`]
pub fn function() {}
pub enum Foo {}
pub fn Foo(){}
warning: `Foo` is both an enum and a function
--> test.rs:1:6
|
1 | /// [`Foo`]
| ^^^^^ ambiguous link
|
= note: `#[warn(broken_intra_doc_links)]` on by default
help: to link to the enum, prefix with the item type
|
1 | /// [`enum@Foo`]
| ^^^^^^^^^^
help: to link to the function, add parentheses
|
1 | /// [`Foo()`]
| ^^^^^^^
This lint is allowed by default. It detects items missing documentation. For example:
#![warn(missing_docs)]
pub fn undocumented() {}
# fn main() {}
The undocumented
function will then have the following warning:
warning: missing documentation for a function
--> your-crate/lib.rs:3:1
|
3 | pub fn undocumented() {}
| ^^^^^^^^^^^^^^^^^^^^^
This lint is allowed by default. It detects if there is no documentation at the crate root. For example:
#![warn(missing_crate_level_docs)]
This will generate the following warning:
warning: no documentation found for this crate's top-level module
|
= help: The following guide may be of use:
https://doc.rust-lang.org/nightly/rustdoc/how-to-write-documentation.html
This is currently "allow" by default, but it is intended to make this a
warning in the future. This is intended as a means to introduce new users on
how to document their crate by pointing them to some instructions on how to
get started, without providing overwhelming warnings like missing_docs
might.
This lint is allowed by default and is nightly-only. It detects when a documentation block is missing a code example. For example:
#![warn(missing_doc_code_examples)]
/// There is no code example!
pub fn no_code_example() {}
# fn main() {}
The no_code_example
function will then have the following warning:
warning: Missing code example in this documentation
--> your-crate/lib.rs:3:1
|
LL | /// There is no code example!
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
To fix the lint, you need to add a code example into the documentation block:
/// There is no code example!
///
/// ```
/// println!("calling no_code_example...");
/// no_code_example();
/// println!("we called no_code_example!");
/// ```
pub fn no_code_example() {}
This lint is allowed by default. It detects documentation tests when they are on a private item. For example:
#![warn(private_doc_tests)]
mod foo {
/// private doc test
///
/// ```
/// assert!(false);
/// ```
fn bar() {}
}
# fn main() {}
Which will give:
warning: Documentation test in private item
--> your-crate/lib.rs:4:1
|
4 | / /// private doc test
5 | | ///
6 | | /// ```
7 | | /// assert!(false);
8 | | /// ```
| |___________^
This lint warns by default. It detects code block attributes in documentation examples that have potentially mis-typed values. For example:
/// Example.
///
/// ```should-panic
/// assert_eq!(1, 2);
/// ```
pub fn foo() {}
Which will give:
warning: unknown attribute `should-panic`. Did you mean `should_panic`?
--> src/lib.rs:1:1
|
1 | / /// Example.
2 | | ///
3 | | /// ```should-panic
4 | | /// assert_eq!(1, 2);
5 | | /// ```
| |_______^
|
= note: `#[warn(invalid_codeblock_attributes)]` on by default
= help: the code block will either not be tested if not marked as a rust one or won't fail if it doesn't panic when running
In the example above, the correct form is should_panic
. This helps detect
typo mistakes for some common attributes.