799 lines
28 KiB
Rust
799 lines
28 KiB
Rust
use clippy_utils::diagnostics::{span_lint, span_lint_and_help, span_lint_and_note};
|
||
use clippy_utils::source::first_line_of_span;
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||
use clippy_utils::ty::{implements_trait, is_type_diagnostic_item};
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||
use clippy_utils::{is_entrypoint_fn, is_expn_of, match_panic_def_id, method_chain_args, return_ty};
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||
use if_chain::if_chain;
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||
use itertools::Itertools;
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||
use rustc_ast::ast::{Async, AttrKind, Attribute, FnKind, FnRetTy, ItemKind};
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||
use rustc_ast::token::CommentKind;
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||
use rustc_data_structures::fx::FxHashSet;
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||
use rustc_data_structures::sync::Lrc;
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||
use rustc_errors::emitter::EmitterWriter;
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||
use rustc_errors::Handler;
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||
use rustc_hir as hir;
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||
use rustc_hir::intravisit::{self, NestedVisitorMap, Visitor};
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||
use rustc_hir::{AnonConst, Expr, ExprKind, QPath};
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||
use rustc_lint::{LateContext, LateLintPass};
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||
use rustc_middle::hir::map::Map;
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||
use rustc_middle::lint::in_external_macro;
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use rustc_middle::ty;
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use rustc_parse::maybe_new_parser_from_source_str;
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||
use rustc_parse::parser::ForceCollect;
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||
use rustc_session::parse::ParseSess;
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||
use rustc_session::{declare_tool_lint, impl_lint_pass};
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use rustc_span::edition::Edition;
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||
use rustc_span::source_map::{BytePos, FilePathMapping, MultiSpan, SourceMap, Span};
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||
use rustc_span::{sym, FileName, Pos};
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use std::io;
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use std::ops::Range;
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use std::thread;
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use url::Url;
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declare_clippy_lint! {
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/// ### What it does
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/// Checks for the presence of `_`, `::` or camel-case words
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/// outside ticks in documentation.
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///
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/// ### Why is this bad?
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/// *Rustdoc* supports markdown formatting, `_`, `::` and
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/// camel-case probably indicates some code which should be included between
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/// ticks. `_` can also be used for emphasis in markdown, this lint tries to
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/// consider that.
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///
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/// ### Known problems
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||
/// Lots of bad docs won’t be fixed, what the lint checks
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/// for is limited, and there are still false positives. HTML elements and their
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/// content are not linted.
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///
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/// In addition, when writing documentation comments, including `[]` brackets
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||
/// inside a link text would trip the parser. Therfore, documenting link with
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/// `[`SmallVec<[T; INLINE_CAPACITY]>`]` and then [`SmallVec<[T; INLINE_CAPACITY]>`]: SmallVec
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/// would fail.
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///
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/// ### Examples
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||
/// ```rust
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||
/// /// Do something with the foo_bar parameter. See also
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/// /// that::other::module::foo.
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/// // ^ `foo_bar` and `that::other::module::foo` should be ticked.
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/// fn doit(foo_bar: usize) {}
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/// ```
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///
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/// ```rust
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/// // Link text with `[]` brackets should be written as following:
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/// /// Consume the array and return the inner
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/// /// [`SmallVec<[T; INLINE_CAPACITY]>`][SmallVec].
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/// /// [SmallVec]: SmallVec
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/// fn main() {}
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/// ```
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pub DOC_MARKDOWN,
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pedantic,
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"presence of `_`, `::` or camel-case outside backticks in documentation"
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}
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declare_clippy_lint! {
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/// ### What it does
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/// Checks for the doc comments of publicly visible
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/// unsafe functions and warns if there is no `# Safety` section.
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///
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/// ### Why is this bad?
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/// Unsafe functions should document their safety
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/// preconditions, so that users can be sure they are using them safely.
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///
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/// ### Examples
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/// ```rust
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///# type Universe = ();
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/// /// This function should really be documented
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/// pub unsafe fn start_apocalypse(u: &mut Universe) {
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/// unimplemented!();
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/// }
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/// ```
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///
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||
/// At least write a line about safety:
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///
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/// ```rust
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///# type Universe = ();
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/// /// # Safety
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/// ///
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/// /// This function should not be called before the horsemen are ready.
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/// pub unsafe fn start_apocalypse(u: &mut Universe) {
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/// unimplemented!();
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/// }
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/// ```
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pub MISSING_SAFETY_DOC,
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||
style,
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"`pub unsafe fn` without `# Safety` docs"
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}
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declare_clippy_lint! {
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/// ### What it does
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/// Checks the doc comments of publicly visible functions that
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/// return a `Result` type and warns if there is no `# Errors` section.
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///
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||
/// ### Why is this bad?
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||
/// Documenting the type of errors that can be returned from a
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/// function can help callers write code to handle the errors appropriately.
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///
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/// ### Examples
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||
/// Since the following function returns a `Result` it has an `# Errors` section in
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/// its doc comment:
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///
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/// ```rust
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///# use std::io;
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/// /// # Errors
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/// ///
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/// /// Will return `Err` if `filename` does not exist or the user does not have
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/// /// permission to read it.
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/// pub fn read(filename: String) -> io::Result<String> {
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/// unimplemented!();
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/// }
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/// ```
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pub MISSING_ERRORS_DOC,
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pedantic,
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"`pub fn` returns `Result` without `# Errors` in doc comment"
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}
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declare_clippy_lint! {
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/// ### What it does
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/// Checks the doc comments of publicly visible functions that
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/// may panic and warns if there is no `# Panics` section.
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///
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/// ### Why is this bad?
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/// Documenting the scenarios in which panicking occurs
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/// can help callers who do not want to panic to avoid those situations.
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///
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/// ### Examples
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/// Since the following function may panic it has a `# Panics` section in
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/// its doc comment:
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///
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/// ```rust
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/// /// # Panics
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/// ///
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/// /// Will panic if y is 0
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/// pub fn divide_by(x: i32, y: i32) -> i32 {
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/// if y == 0 {
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/// panic!("Cannot divide by 0")
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/// } else {
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/// x / y
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/// }
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/// }
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/// ```
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pub MISSING_PANICS_DOC,
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pedantic,
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"`pub fn` may panic without `# Panics` in doc comment"
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}
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declare_clippy_lint! {
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/// ### What it does
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/// Checks for `fn main() { .. }` in doctests
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///
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||
/// ### Why is this bad?
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||
/// The test can be shorter (and likely more readable)
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/// if the `fn main()` is left implicit.
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///
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/// ### Examples
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||
/// ``````rust
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/// /// An example of a doctest with a `main()` function
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/// ///
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/// /// # Examples
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/// ///
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/// /// ```
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||
/// /// fn main() {
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/// /// // this needs not be in an `fn`
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/// /// }
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/// /// ```
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/// fn needless_main() {
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/// unimplemented!();
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/// }
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/// ``````
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pub NEEDLESS_DOCTEST_MAIN,
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style,
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"presence of `fn main() {` in code examples"
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}
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#[allow(clippy::module_name_repetitions)]
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#[derive(Clone)]
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pub struct DocMarkdown {
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valid_idents: FxHashSet<String>,
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in_trait_impl: bool,
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}
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impl DocMarkdown {
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pub fn new(valid_idents: FxHashSet<String>) -> Self {
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Self {
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valid_idents,
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in_trait_impl: false,
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}
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}
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||
}
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impl_lint_pass!(DocMarkdown =>
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[DOC_MARKDOWN, MISSING_SAFETY_DOC, MISSING_ERRORS_DOC, MISSING_PANICS_DOC, NEEDLESS_DOCTEST_MAIN]
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);
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impl<'tcx> LateLintPass<'tcx> for DocMarkdown {
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||
fn check_crate(&mut self, cx: &LateContext<'tcx>, _: &'tcx hir::Crate<'_>) {
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let attrs = cx.tcx.hir().attrs(hir::CRATE_HIR_ID);
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check_attrs(cx, &self.valid_idents, attrs);
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}
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fn check_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx hir::Item<'_>) {
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let attrs = cx.tcx.hir().attrs(item.hir_id());
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let headers = check_attrs(cx, &self.valid_idents, attrs);
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match item.kind {
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hir::ItemKind::Fn(ref sig, _, body_id) => {
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if !(is_entrypoint_fn(cx, item.def_id.to_def_id()) || in_external_macro(cx.tcx.sess, item.span)) {
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||
let body = cx.tcx.hir().body(body_id);
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let mut fpu = FindPanicUnwrap {
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cx,
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typeck_results: cx.tcx.typeck(item.def_id),
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panic_span: None,
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||
};
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||
fpu.visit_expr(&body.value);
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lint_for_missing_headers(
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cx,
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item.hir_id(),
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item.span,
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sig,
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||
headers,
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||
Some(body_id),
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fpu.panic_span,
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||
);
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||
}
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||
},
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||
hir::ItemKind::Impl(ref impl_) => {
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||
self.in_trait_impl = impl_.of_trait.is_some();
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||
},
|
||
_ => {},
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||
}
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||
}
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||
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||
fn check_item_post(&mut self, _cx: &LateContext<'tcx>, item: &'tcx hir::Item<'_>) {
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||
if let hir::ItemKind::Impl { .. } = item.kind {
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self.in_trait_impl = false;
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||
}
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||
}
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||
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||
fn check_trait_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx hir::TraitItem<'_>) {
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||
let attrs = cx.tcx.hir().attrs(item.hir_id());
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||
let headers = check_attrs(cx, &self.valid_idents, attrs);
|
||
if let hir::TraitItemKind::Fn(ref sig, ..) = item.kind {
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||
if !in_external_macro(cx.tcx.sess, item.span) {
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||
lint_for_missing_headers(cx, item.hir_id(), item.span, sig, headers, None, None);
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||
}
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||
}
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||
}
|
||
|
||
fn check_impl_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx hir::ImplItem<'_>) {
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||
let attrs = cx.tcx.hir().attrs(item.hir_id());
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||
let headers = check_attrs(cx, &self.valid_idents, attrs);
|
||
if self.in_trait_impl || in_external_macro(cx.tcx.sess, item.span) {
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||
return;
|
||
}
|
||
if let hir::ImplItemKind::Fn(ref sig, body_id) = item.kind {
|
||
let body = cx.tcx.hir().body(body_id);
|
||
let mut fpu = FindPanicUnwrap {
|
||
cx,
|
||
typeck_results: cx.tcx.typeck(item.def_id),
|
||
panic_span: None,
|
||
};
|
||
fpu.visit_expr(&body.value);
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||
lint_for_missing_headers(
|
||
cx,
|
||
item.hir_id(),
|
||
item.span,
|
||
sig,
|
||
headers,
|
||
Some(body_id),
|
||
fpu.panic_span,
|
||
);
|
||
}
|
||
}
|
||
}
|
||
|
||
fn lint_for_missing_headers<'tcx>(
|
||
cx: &LateContext<'tcx>,
|
||
hir_id: hir::HirId,
|
||
span: impl Into<MultiSpan> + Copy,
|
||
sig: &hir::FnSig<'_>,
|
||
headers: DocHeaders,
|
||
body_id: Option<hir::BodyId>,
|
||
panic_span: Option<Span>,
|
||
) {
|
||
if !cx.access_levels.is_exported(hir_id) {
|
||
return; // Private functions do not require doc comments
|
||
}
|
||
if !headers.safety && sig.header.unsafety == hir::Unsafety::Unsafe {
|
||
span_lint(
|
||
cx,
|
||
MISSING_SAFETY_DOC,
|
||
span,
|
||
"unsafe function's docs miss `# Safety` section",
|
||
);
|
||
}
|
||
if !headers.panics && panic_span.is_some() {
|
||
span_lint_and_note(
|
||
cx,
|
||
MISSING_PANICS_DOC,
|
||
span,
|
||
"docs for function which may panic missing `# Panics` section",
|
||
panic_span,
|
||
"first possible panic found here",
|
||
);
|
||
}
|
||
if !headers.errors {
|
||
if is_type_diagnostic_item(cx, return_ty(cx, hir_id), sym::result_type) {
|
||
span_lint(
|
||
cx,
|
||
MISSING_ERRORS_DOC,
|
||
span,
|
||
"docs for function returning `Result` missing `# Errors` section",
|
||
);
|
||
} else {
|
||
if_chain! {
|
||
if let Some(body_id) = body_id;
|
||
if let Some(future) = cx.tcx.lang_items().future_trait();
|
||
let typeck = cx.tcx.typeck_body(body_id);
|
||
let body = cx.tcx.hir().body(body_id);
|
||
let ret_ty = typeck.expr_ty(&body.value);
|
||
if implements_trait(cx, ret_ty, future, &[]);
|
||
if let ty::Opaque(_, subs) = ret_ty.kind();
|
||
if let Some(gen) = subs.types().next();
|
||
if let ty::Generator(_, subs, _) = gen.kind();
|
||
if is_type_diagnostic_item(cx, subs.as_generator().return_ty(), sym::result_type);
|
||
then {
|
||
span_lint(
|
||
cx,
|
||
MISSING_ERRORS_DOC,
|
||
span,
|
||
"docs for function returning `Result` missing `# Errors` section",
|
||
);
|
||
}
|
||
}
|
||
}
|
||
}
|
||
}
|
||
|
||
/// Cleanup documentation decoration.
|
||
///
|
||
/// We can't use `rustc_ast::attr::AttributeMethods::with_desugared_doc` or
|
||
/// `rustc_ast::parse::lexer::comments::strip_doc_comment_decoration` because we
|
||
/// need to keep track of
|
||
/// the spans but this function is inspired from the later.
|
||
#[allow(clippy::cast_possible_truncation)]
|
||
#[must_use]
|
||
pub fn strip_doc_comment_decoration(doc: &str, comment_kind: CommentKind, span: Span) -> (String, Vec<(usize, Span)>) {
|
||
// one-line comments lose their prefix
|
||
if comment_kind == CommentKind::Line {
|
||
let mut doc = doc.to_owned();
|
||
doc.push('\n');
|
||
let len = doc.len();
|
||
// +3 skips the opening delimiter
|
||
return (doc, vec![(len, span.with_lo(span.lo() + BytePos(3)))]);
|
||
}
|
||
|
||
let mut sizes = vec![];
|
||
let mut contains_initial_stars = false;
|
||
for line in doc.lines() {
|
||
let offset = line.as_ptr() as usize - doc.as_ptr() as usize;
|
||
debug_assert_eq!(offset as u32 as usize, offset);
|
||
contains_initial_stars |= line.trim_start().starts_with('*');
|
||
// +1 adds the newline, +3 skips the opening delimiter
|
||
sizes.push((line.len() + 1, span.with_lo(span.lo() + BytePos(3 + offset as u32))));
|
||
}
|
||
if !contains_initial_stars {
|
||
return (doc.to_string(), sizes);
|
||
}
|
||
// remove the initial '*'s if any
|
||
let mut no_stars = String::with_capacity(doc.len());
|
||
for line in doc.lines() {
|
||
let mut chars = line.chars();
|
||
for c in &mut chars {
|
||
if c.is_whitespace() {
|
||
no_stars.push(c);
|
||
} else {
|
||
no_stars.push(if c == '*' { ' ' } else { c });
|
||
break;
|
||
}
|
||
}
|
||
no_stars.push_str(chars.as_str());
|
||
no_stars.push('\n');
|
||
}
|
||
|
||
(no_stars, sizes)
|
||
}
|
||
|
||
#[derive(Copy, Clone)]
|
||
struct DocHeaders {
|
||
safety: bool,
|
||
errors: bool,
|
||
panics: bool,
|
||
}
|
||
|
||
fn check_attrs<'a>(cx: &LateContext<'_>, valid_idents: &FxHashSet<String>, attrs: &'a [Attribute]) -> DocHeaders {
|
||
let mut doc = String::new();
|
||
let mut spans = vec![];
|
||
|
||
for attr in attrs {
|
||
if let AttrKind::DocComment(comment_kind, comment) = attr.kind {
|
||
let (comment, current_spans) = strip_doc_comment_decoration(&comment.as_str(), comment_kind, attr.span);
|
||
spans.extend_from_slice(¤t_spans);
|
||
doc.push_str(&comment);
|
||
} else if attr.has_name(sym::doc) {
|
||
// ignore mix of sugared and non-sugared doc
|
||
// don't trigger the safety or errors check
|
||
return DocHeaders {
|
||
safety: true,
|
||
errors: true,
|
||
panics: true,
|
||
};
|
||
}
|
||
}
|
||
|
||
let mut current = 0;
|
||
for &mut (ref mut offset, _) in &mut spans {
|
||
let offset_copy = *offset;
|
||
*offset = current;
|
||
current += offset_copy;
|
||
}
|
||
|
||
if doc.is_empty() {
|
||
return DocHeaders {
|
||
safety: false,
|
||
errors: false,
|
||
panics: false,
|
||
};
|
||
}
|
||
|
||
let parser = pulldown_cmark::Parser::new(&doc).into_offset_iter();
|
||
// Iterate over all `Events` and combine consecutive events into one
|
||
let events = parser.coalesce(|previous, current| {
|
||
use pulldown_cmark::Event::Text;
|
||
|
||
let previous_range = previous.1;
|
||
let current_range = current.1;
|
||
|
||
match (previous.0, current.0) {
|
||
(Text(previous), Text(current)) => {
|
||
let mut previous = previous.to_string();
|
||
previous.push_str(¤t);
|
||
Ok((Text(previous.into()), previous_range))
|
||
},
|
||
(previous, current) => Err(((previous, previous_range), (current, current_range))),
|
||
}
|
||
});
|
||
check_doc(cx, valid_idents, events, &spans)
|
||
}
|
||
|
||
const RUST_CODE: &[&str] = &["rust", "no_run", "should_panic", "compile_fail"];
|
||
|
||
fn check_doc<'a, Events: Iterator<Item = (pulldown_cmark::Event<'a>, Range<usize>)>>(
|
||
cx: &LateContext<'_>,
|
||
valid_idents: &FxHashSet<String>,
|
||
events: Events,
|
||
spans: &[(usize, Span)],
|
||
) -> DocHeaders {
|
||
// true if a safety header was found
|
||
use pulldown_cmark::Event::{
|
||
Code, End, FootnoteReference, HardBreak, Html, Rule, SoftBreak, Start, TaskListMarker, Text,
|
||
};
|
||
use pulldown_cmark::Tag::{CodeBlock, Heading, Item, Link, Paragraph};
|
||
use pulldown_cmark::{CodeBlockKind, CowStr};
|
||
|
||
let mut headers = DocHeaders {
|
||
safety: false,
|
||
errors: false,
|
||
panics: false,
|
||
};
|
||
let mut in_code = false;
|
||
let mut in_link = None;
|
||
let mut in_heading = false;
|
||
let mut is_rust = false;
|
||
let mut edition = None;
|
||
let mut ticks_unbalanced = false;
|
||
let mut text_to_check: Vec<(CowStr<'_>, Span)> = Vec::new();
|
||
let mut paragraph_span = spans.get(0).expect("function isn't called if doc comment is empty").1;
|
||
for (event, range) in events {
|
||
match event {
|
||
Start(CodeBlock(ref kind)) => {
|
||
in_code = true;
|
||
if let CodeBlockKind::Fenced(lang) = kind {
|
||
for item in lang.split(',') {
|
||
if item == "ignore" {
|
||
is_rust = false;
|
||
break;
|
||
}
|
||
if let Some(stripped) = item.strip_prefix("edition") {
|
||
is_rust = true;
|
||
edition = stripped.parse::<Edition>().ok();
|
||
} else if item.is_empty() || RUST_CODE.contains(&item) {
|
||
is_rust = true;
|
||
}
|
||
}
|
||
}
|
||
},
|
||
End(CodeBlock(_)) => {
|
||
in_code = false;
|
||
is_rust = false;
|
||
},
|
||
Start(Link(_, url, _)) => in_link = Some(url),
|
||
End(Link(..)) => in_link = None,
|
||
Start(Heading(_) | Paragraph | Item) => {
|
||
if let Start(Heading(_)) = event {
|
||
in_heading = true;
|
||
}
|
||
ticks_unbalanced = false;
|
||
let (_, span) = get_current_span(spans, range.start);
|
||
paragraph_span = first_line_of_span(cx, span);
|
||
},
|
||
End(Heading(_) | Paragraph | Item) => {
|
||
if let End(Heading(_)) = event {
|
||
in_heading = false;
|
||
}
|
||
if ticks_unbalanced {
|
||
span_lint_and_help(
|
||
cx,
|
||
DOC_MARKDOWN,
|
||
paragraph_span,
|
||
"backticks are unbalanced",
|
||
None,
|
||
"a backtick may be missing a pair",
|
||
);
|
||
} else {
|
||
for (text, span) in text_to_check {
|
||
check_text(cx, valid_idents, &text, span);
|
||
}
|
||
}
|
||
text_to_check = Vec::new();
|
||
},
|
||
Start(_tag) | End(_tag) => (), // We don't care about other tags
|
||
Html(_html) => (), // HTML is weird, just ignore it
|
||
SoftBreak | HardBreak | TaskListMarker(_) | Code(_) | Rule => (),
|
||
FootnoteReference(text) | Text(text) => {
|
||
let (begin, span) = get_current_span(spans, range.start);
|
||
paragraph_span = paragraph_span.with_hi(span.hi());
|
||
ticks_unbalanced |= text.contains('`') && !in_code;
|
||
if Some(&text) == in_link.as_ref() || ticks_unbalanced {
|
||
// Probably a link of the form `<http://example.com>`
|
||
// Which are represented as a link to "http://example.com" with
|
||
// text "http://example.com" by pulldown-cmark
|
||
continue;
|
||
}
|
||
headers.safety |= in_heading && text.trim() == "Safety";
|
||
headers.errors |= in_heading && text.trim() == "Errors";
|
||
headers.panics |= in_heading && text.trim() == "Panics";
|
||
if in_code {
|
||
if is_rust {
|
||
let edition = edition.unwrap_or_else(|| cx.tcx.sess.edition());
|
||
check_code(cx, &text, edition, span);
|
||
}
|
||
} else {
|
||
// Adjust for the beginning of the current `Event`
|
||
let span = span.with_lo(span.lo() + BytePos::from_usize(range.start - begin));
|
||
text_to_check.push((text, span));
|
||
}
|
||
},
|
||
}
|
||
}
|
||
headers
|
||
}
|
||
|
||
fn get_current_span(spans: &[(usize, Span)], idx: usize) -> (usize, Span) {
|
||
let index = match spans.binary_search_by(|c| c.0.cmp(&idx)) {
|
||
Ok(o) => o,
|
||
Err(e) => e - 1,
|
||
};
|
||
spans[index]
|
||
}
|
||
|
||
fn check_code(cx: &LateContext<'_>, text: &str, edition: Edition, span: Span) {
|
||
fn has_needless_main(code: String, edition: Edition) -> bool {
|
||
rustc_driver::catch_fatal_errors(|| {
|
||
rustc_span::create_session_globals_then(edition, || {
|
||
let filename = FileName::anon_source_code(&code);
|
||
|
||
let sm = Lrc::new(SourceMap::new(FilePathMapping::empty()));
|
||
let emitter = EmitterWriter::new(box io::sink(), None, false, false, false, None, false);
|
||
let handler = Handler::with_emitter(false, None, box emitter);
|
||
let sess = ParseSess::with_span_handler(handler, sm);
|
||
|
||
let mut parser = match maybe_new_parser_from_source_str(&sess, filename, code) {
|
||
Ok(p) => p,
|
||
Err(errs) => {
|
||
for mut err in errs {
|
||
err.cancel();
|
||
}
|
||
return false;
|
||
},
|
||
};
|
||
|
||
let mut relevant_main_found = false;
|
||
loop {
|
||
match parser.parse_item(ForceCollect::No) {
|
||
Ok(Some(item)) => match &item.kind {
|
||
// Tests with one of these items are ignored
|
||
ItemKind::Static(..)
|
||
| ItemKind::Const(..)
|
||
| ItemKind::ExternCrate(..)
|
||
| ItemKind::ForeignMod(..) => return false,
|
||
// We found a main function ...
|
||
ItemKind::Fn(box FnKind(_, sig, _, Some(block))) if item.ident.name == sym::main => {
|
||
let is_async = matches!(sig.header.asyncness, Async::Yes { .. });
|
||
let returns_nothing = match &sig.decl.output {
|
||
FnRetTy::Default(..) => true,
|
||
FnRetTy::Ty(ty) if ty.kind.is_unit() => true,
|
||
FnRetTy::Ty(_) => false,
|
||
};
|
||
|
||
if returns_nothing && !is_async && !block.stmts.is_empty() {
|
||
// This main function should be linted, but only if there are no other functions
|
||
relevant_main_found = true;
|
||
} else {
|
||
// This main function should not be linted, we're done
|
||
return false;
|
||
}
|
||
},
|
||
// Another function was found; this case is ignored too
|
||
ItemKind::Fn(..) => return false,
|
||
_ => {},
|
||
},
|
||
Ok(None) => break,
|
||
Err(mut e) => {
|
||
e.cancel();
|
||
return false;
|
||
},
|
||
}
|
||
}
|
||
|
||
relevant_main_found
|
||
})
|
||
})
|
||
.ok()
|
||
.unwrap_or_default()
|
||
}
|
||
|
||
// Because of the global session, we need to create a new session in a different thread with
|
||
// the edition we need.
|
||
let text = text.to_owned();
|
||
if thread::spawn(move || has_needless_main(text, edition))
|
||
.join()
|
||
.expect("thread::spawn failed")
|
||
{
|
||
span_lint(cx, NEEDLESS_DOCTEST_MAIN, span, "needless `fn main` in doctest");
|
||
}
|
||
}
|
||
|
||
fn check_text(cx: &LateContext<'_>, valid_idents: &FxHashSet<String>, text: &str, span: Span) {
|
||
for word in text.split(|c: char| c.is_whitespace() || c == '\'') {
|
||
// Trim punctuation as in `some comment (see foo::bar).`
|
||
// ^^
|
||
// Or even as in `_foo bar_` which is emphasized.
|
||
let word = word.trim_matches(|c: char| !c.is_alphanumeric());
|
||
|
||
if valid_idents.contains(word) {
|
||
continue;
|
||
}
|
||
|
||
// Adjust for the current word
|
||
let offset = word.as_ptr() as usize - text.as_ptr() as usize;
|
||
let span = Span::new(
|
||
span.lo() + BytePos::from_usize(offset),
|
||
span.lo() + BytePos::from_usize(offset + word.len()),
|
||
span.ctxt(),
|
||
);
|
||
|
||
check_word(cx, word, span);
|
||
}
|
||
}
|
||
|
||
fn check_word(cx: &LateContext<'_>, word: &str, span: Span) {
|
||
/// Checks if a string is camel-case, i.e., contains at least two uppercase
|
||
/// letters (`Clippy` is ok) and one lower-case letter (`NASA` is ok).
|
||
/// Plurals are also excluded (`IDs` is ok).
|
||
fn is_camel_case(s: &str) -> bool {
|
||
if s.starts_with(|c: char| c.is_digit(10)) {
|
||
return false;
|
||
}
|
||
|
||
let s = s.strip_suffix('s').unwrap_or(s);
|
||
|
||
s.chars().all(char::is_alphanumeric)
|
||
&& s.chars().filter(|&c| c.is_uppercase()).take(2).count() > 1
|
||
&& s.chars().filter(|&c| c.is_lowercase()).take(1).count() > 0
|
||
}
|
||
|
||
fn has_underscore(s: &str) -> bool {
|
||
s != "_" && !s.contains("\\_") && s.contains('_')
|
||
}
|
||
|
||
fn has_hyphen(s: &str) -> bool {
|
||
s != "-" && s.contains('-')
|
||
}
|
||
|
||
if let Ok(url) = Url::parse(word) {
|
||
// try to get around the fact that `foo::bar` parses as a valid URL
|
||
if !url.cannot_be_a_base() {
|
||
span_lint(
|
||
cx,
|
||
DOC_MARKDOWN,
|
||
span,
|
||
"you should put bare URLs between `<`/`>` or make a proper Markdown link",
|
||
);
|
||
|
||
return;
|
||
}
|
||
}
|
||
|
||
// We assume that mixed-case words are not meant to be put inside bacticks. (Issue #2343)
|
||
if has_underscore(word) && has_hyphen(word) {
|
||
return;
|
||
}
|
||
|
||
if has_underscore(word) || word.contains("::") || is_camel_case(word) {
|
||
span_lint(
|
||
cx,
|
||
DOC_MARKDOWN,
|
||
span,
|
||
&format!("you should put `{}` between ticks in the documentation", word),
|
||
);
|
||
}
|
||
}
|
||
|
||
struct FindPanicUnwrap<'a, 'tcx> {
|
||
cx: &'a LateContext<'tcx>,
|
||
panic_span: Option<Span>,
|
||
typeck_results: &'tcx ty::TypeckResults<'tcx>,
|
||
}
|
||
|
||
impl<'a, 'tcx> Visitor<'tcx> for FindPanicUnwrap<'a, 'tcx> {
|
||
type Map = Map<'tcx>;
|
||
|
||
fn visit_expr(&mut self, expr: &'tcx Expr<'_>) {
|
||
if self.panic_span.is_some() {
|
||
return;
|
||
}
|
||
|
||
// check for `begin_panic`
|
||
if_chain! {
|
||
if let ExprKind::Call(func_expr, _) = expr.kind;
|
||
if let ExprKind::Path(QPath::Resolved(_, path)) = func_expr.kind;
|
||
if let Some(path_def_id) = path.res.opt_def_id();
|
||
if match_panic_def_id(self.cx, path_def_id);
|
||
if is_expn_of(expr.span, "unreachable").is_none();
|
||
if !is_expn_of_debug_assertions(expr.span);
|
||
then {
|
||
self.panic_span = Some(expr.span);
|
||
}
|
||
}
|
||
|
||
// check for `assert_eq` or `assert_ne`
|
||
if is_expn_of(expr.span, "assert_eq").is_some() || is_expn_of(expr.span, "assert_ne").is_some() {
|
||
self.panic_span = Some(expr.span);
|
||
}
|
||
|
||
// check for `unwrap`
|
||
if let Some(arglists) = method_chain_args(expr, &["unwrap"]) {
|
||
let reciever_ty = self.typeck_results.expr_ty(&arglists[0][0]).peel_refs();
|
||
if is_type_diagnostic_item(self.cx, reciever_ty, sym::option_type)
|
||
|| is_type_diagnostic_item(self.cx, reciever_ty, sym::result_type)
|
||
{
|
||
self.panic_span = Some(expr.span);
|
||
}
|
||
}
|
||
|
||
// and check sub-expressions
|
||
intravisit::walk_expr(self, expr);
|
||
}
|
||
|
||
// Panics in const blocks will cause compilation to fail.
|
||
fn visit_anon_const(&mut self, _: &'tcx AnonConst) {}
|
||
|
||
fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
|
||
NestedVisitorMap::OnlyBodies(self.cx.tcx.hir())
|
||
}
|
||
}
|
||
|
||
fn is_expn_of_debug_assertions(span: Span) -> bool {
|
||
const MACRO_NAMES: &[&str] = &["debug_assert", "debug_assert_eq", "debug_assert_ne"];
|
||
MACRO_NAMES.iter().any(|name| is_expn_of(span, name).is_some())
|
||
}
|