--- /dev/null
+//! Clippy wrappers around rustc's diagnostic functions.
+
+use rustc_errors::{Applicability, DiagnosticBuilder};
+use rustc_hir::HirId;
+use rustc_lint::{LateContext, Lint, LintContext};
+use rustc_span::source_map::{MultiSpan, Span};
+use std::env;
+
+fn docs_link(diag: &mut DiagnosticBuilder<'_>, lint: &'static Lint) {
+ if env::var("CLIPPY_DISABLE_DOCS_LINKS").is_err() {
+ diag.help(&format!(
+ "for further information visit https://rust-lang.github.io/rust-clippy/{}/index.html#{}",
+ &option_env!("RUST_RELEASE_NUM").map_or("master".to_string(), |n| {
+ // extract just major + minor version and ignore patch versions
+ format!("rust-{}", n.rsplitn(2, '.').nth(1).unwrap())
+ }),
+ lint.name_lower().replacen("clippy::", "", 1)
+ ));
+ }
+}
+
+/// Emit a basic lint message with a `msg` and a `span`.
+///
+/// This is the most primitive of our lint emission methods and can
+/// be a good way to get a new lint started.
+///
+/// Usually it's nicer to provide more context for lint messages.
+/// Be sure the output is understandable when you use this method.
+///
+/// # Example
+///
+/// ```ignore
+/// error: usage of mem::forget on Drop type
+/// --> $DIR/mem_forget.rs:17:5
+/// |
+/// 17 | std::mem::forget(seven);
+/// | ^^^^^^^^^^^^^^^^^^^^^^^
+/// ```
+pub fn span_lint<T: LintContext>(cx: &T, lint: &'static Lint, sp: impl Into<MultiSpan>, msg: &str) {
+ cx.struct_span_lint(lint, sp, |diag| {
+ let mut diag = diag.build(msg);
+ docs_link(&mut diag, lint);
+ diag.emit();
+ });
+}
+
+/// Same as `span_lint` but with an extra `help` message.
+///
+/// Use this if you want to provide some general help but
+/// can't provide a specific machine applicable suggestion.
+///
+/// The `help` message can be optionally attached to a `Span`.
+///
+/// If you change the signature, remember to update the internal lint `CollapsibleCalls`
+///
+/// # Example
+///
+/// ```ignore
+/// error: constant division of 0.0 with 0.0 will always result in NaN
+/// --> $DIR/zero_div_zero.rs:6:25
+/// |
+/// 6 | let other_f64_nan = 0.0f64 / 0.0;
+/// | ^^^^^^^^^^^^
+/// |
+/// = help: Consider using `f64::NAN` if you would like a constant representing NaN
+/// ```
+pub fn span_lint_and_help<'a, T: LintContext>(
+ cx: &'a T,
+ lint: &'static Lint,
+ span: Span,
+ msg: &str,
+ help_span: Option<Span>,
+ help: &str,
+) {
+ cx.struct_span_lint(lint, span, |diag| {
+ let mut diag = diag.build(msg);
+ if let Some(help_span) = help_span {
+ diag.span_help(help_span, help);
+ } else {
+ diag.help(help);
+ }
+ docs_link(&mut diag, lint);
+ diag.emit();
+ });
+}
+
+/// Like `span_lint` but with a `note` section instead of a `help` message.
+///
+/// The `note` message is presented separately from the main lint message
+/// and is attached to a specific span:
+///
+/// If you change the signature, remember to update the internal lint `CollapsibleCalls`
+///
+/// # Example
+///
+/// ```ignore
+/// error: calls to `std::mem::forget` with a reference instead of an owned value. Forgetting a reference does nothing.
+/// --> $DIR/drop_forget_ref.rs:10:5
+/// |
+/// 10 | forget(&SomeStruct);
+/// | ^^^^^^^^^^^^^^^^^^^
+/// |
+/// = note: `-D clippy::forget-ref` implied by `-D warnings`
+/// note: argument has type &SomeStruct
+/// --> $DIR/drop_forget_ref.rs:10:12
+/// |
+/// 10 | forget(&SomeStruct);
+/// | ^^^^^^^^^^^
+/// ```
+pub fn span_lint_and_note<'a, T: LintContext>(
+ cx: &'a T,
+ lint: &'static Lint,
+ span: impl Into<MultiSpan>,
+ msg: &str,
+ note_span: Option<Span>,
+ note: &str,
+) {
+ cx.struct_span_lint(lint, span, |diag| {
+ let mut diag = diag.build(msg);
+ if let Some(note_span) = note_span {
+ diag.span_note(note_span, note);
+ } else {
+ diag.note(note);
+ }
+ docs_link(&mut diag, lint);
+ diag.emit();
+ });
+}
+
+/// Like `span_lint` but allows to add notes, help and suggestions using a closure.
+///
+/// If you need to customize your lint output a lot, use this function.
+/// If you change the signature, remember to update the internal lint `CollapsibleCalls`
+pub fn span_lint_and_then<'a, T: LintContext, F>(cx: &'a T, lint: &'static Lint, sp: Span, msg: &str, f: F)
+where
+ F: for<'b> FnOnce(&mut DiagnosticBuilder<'b>),
+{
+ cx.struct_span_lint(lint, sp, |diag| {
+ let mut diag = diag.build(msg);
+ f(&mut diag);
+ docs_link(&mut diag, lint);
+ diag.emit();
+ });
+}
+
+pub fn span_lint_hir(cx: &LateContext<'_>, lint: &'static Lint, hir_id: HirId, sp: Span, msg: &str) {
+ cx.tcx.struct_span_lint_hir(lint, hir_id, sp, |diag| {
+ let mut diag = diag.build(msg);
+ docs_link(&mut diag, lint);
+ diag.emit();
+ });
+}
+
+pub fn span_lint_hir_and_then(
+ cx: &LateContext<'_>,
+ lint: &'static Lint,
+ hir_id: HirId,
+ sp: Span,
+ msg: &str,
+ f: impl FnOnce(&mut DiagnosticBuilder<'_>),
+) {
+ cx.tcx.struct_span_lint_hir(lint, hir_id, sp, |diag| {
+ let mut diag = diag.build(msg);
+ f(&mut diag);
+ docs_link(&mut diag, lint);
+ diag.emit();
+ });
+}
+
+/// Add a span lint with a suggestion on how to fix it.
+///
+/// These suggestions can be parsed by rustfix to allow it to automatically fix your code.
+/// In the example below, `help` is `"try"` and `sugg` is the suggested replacement `".any(|x| x >
+/// 2)"`.
+///
+/// If you change the signature, remember to update the internal lint `CollapsibleCalls`
+///
+/// # Example
+///
+/// ```ignore
+/// error: This `.fold` can be more succinctly expressed as `.any`
+/// --> $DIR/methods.rs:390:13
+/// |
+/// 390 | let _ = (0..3).fold(false, |acc, x| acc || x > 2);
+/// | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `.any(|x| x > 2)`
+/// |
+/// = note: `-D fold-any` implied by `-D warnings`
+/// ```
+#[cfg_attr(feature = "internal-lints", allow(clippy::collapsible_span_lint_calls))]
+pub fn span_lint_and_sugg<'a, T: LintContext>(
+ cx: &'a T,
+ lint: &'static Lint,
+ sp: Span,
+ msg: &str,
+ help: &str,
+ sugg: String,
+ applicability: Applicability,
+) {
+ span_lint_and_then(cx, lint, sp, msg, |diag| {
+ diag.span_suggestion(sp, help, sugg, applicability);
+ });
+}
+
+/// Create a suggestion made from several `span → replacement`.
+///
+/// Note: in the JSON format (used by `compiletest_rs`), the help message will
+/// appear once per
+/// replacement. In human-readable format though, it only appears once before
+/// the whole suggestion.
+pub fn multispan_sugg<I>(diag: &mut DiagnosticBuilder<'_>, help_msg: &str, sugg: I)
+where
+ I: IntoIterator<Item = (Span, String)>,
+{
+ multispan_sugg_with_applicability(diag, help_msg, Applicability::Unspecified, sugg)
+}
+
+pub fn multispan_sugg_with_applicability<I>(
+ diag: &mut DiagnosticBuilder<'_>,
+ help_msg: &str,
+ applicability: Applicability,
+ sugg: I,
+) where
+ I: IntoIterator<Item = (Span, String)>,
+{
+ diag.multipart_suggestion(help_msg, sugg.into_iter().collect(), applicability);
+}
projects / rustc.git / blobdiff