Lints
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:
intra_doc_link_resolution_failure
This lint warns by default and is nightly-only. This lint detects when an intra-doc link fails to get resolved. For example:
#![allow(unused_variables)] fn main() { /// I want to link to [`Inexistent`] but it doesn't exist! pub fn foo() {} }
You'll get a warning saying:
error: `[`Inexistent`]` cannot be resolved, ignoring it...
missing_docs
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() {}
   | ^^^^^^^^^^^^^^^^^^^^^
missing_doc_code_examples
This lint is allowed by default. 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:
#![allow(unused_variables)] fn main() { /// There is no code example! /// /// ``` /// println!("calling no_code_example..."); /// no_code_example(); /// println!("we called no_code_example!"); /// ``` pub fn no_code_example() {} }
private_doc_tests
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 | |     /// ```
   | |___________^