| use clippy_config::msrvs::{self, Msrv}; |
| use clippy_utils::diagnostics::span_lint_and_then; |
| use clippy_utils::source::{trim_span, walk_span_to_context}; |
| use rustc_ast::ast::{Expr, ExprKind, LitKind, Pat, PatKind, RangeEnd, RangeLimits}; |
| use rustc_errors::Applicability; |
| use rustc_lint::{EarlyContext, EarlyLintPass, LintContext}; |
| use rustc_middle::lint::in_external_macro; |
| use rustc_session::{declare_tool_lint, impl_lint_pass}; |
| use rustc_span::Span; |
| |
| declare_clippy_lint! { |
| /// ### What it does |
| /// Checks for ranges which almost include the entire range of letters from 'a' to 'z' |
| /// or digits from '0' to '9', but don't because they're a half open range. |
| /// |
| /// ### Why is this bad? |
| /// This (`'a'..'z'`) is almost certainly a typo meant to include all letters. |
| /// |
| /// ### Example |
| /// ```no_run |
| /// let _ = 'a'..'z'; |
| /// ``` |
| /// Use instead: |
| /// ```no_run |
| /// let _ = 'a'..='z'; |
| /// ``` |
| #[clippy::version = "1.68.0"] |
| pub ALMOST_COMPLETE_RANGE, |
| suspicious, |
| "almost complete range" |
| } |
| impl_lint_pass!(AlmostCompleteRange => [ALMOST_COMPLETE_RANGE]); |
| |
| pub struct AlmostCompleteRange { |
| msrv: Msrv, |
| } |
| impl AlmostCompleteRange { |
| pub fn new(msrv: Msrv) -> Self { |
| Self { msrv } |
| } |
| } |
| impl EarlyLintPass for AlmostCompleteRange { |
| fn check_expr(&mut self, cx: &EarlyContext<'_>, e: &Expr) { |
| if let ExprKind::Range(Some(start), Some(end), RangeLimits::HalfOpen) = &e.kind { |
| let ctxt = e.span.ctxt(); |
| let sugg = if let Some(start) = walk_span_to_context(start.span, ctxt) |
| && let Some(end) = walk_span_to_context(end.span, ctxt) |
| && self.msrv.meets(msrvs::RANGE_INCLUSIVE) |
| { |
| Some((trim_span(cx.sess().source_map(), start.between(end)), "..=")) |
| } else { |
| None |
| }; |
| check_range(cx, e.span, start, end, sugg); |
| } |
| } |
| |
| fn check_pat(&mut self, cx: &EarlyContext<'_>, p: &Pat) { |
| if let PatKind::Range(Some(start), Some(end), kind) = &p.kind |
| && matches!(kind.node, RangeEnd::Excluded) |
| { |
| let sugg = if self.msrv.meets(msrvs::RANGE_INCLUSIVE) { |
| "..=" |
| } else { |
| "..." |
| }; |
| check_range(cx, p.span, start, end, Some((kind.span, sugg))); |
| } |
| } |
| |
| extract_msrv_attr!(EarlyContext); |
| } |
| |
| fn check_range(cx: &EarlyContext<'_>, span: Span, start: &Expr, end: &Expr, sugg: Option<(Span, &str)>) { |
| if let ExprKind::Lit(start_token_lit) = start.peel_parens().kind |
| && let ExprKind::Lit(end_token_lit) = end.peel_parens().kind |
| && matches!( |
| ( |
| LitKind::from_token_lit(start_token_lit), |
| LitKind::from_token_lit(end_token_lit), |
| ), |
| ( |
| Ok(LitKind::Byte(b'a') | LitKind::Char('a')), |
| Ok(LitKind::Byte(b'z') | LitKind::Char('z')) |
| ) | ( |
| Ok(LitKind::Byte(b'A') | LitKind::Char('A')), |
| Ok(LitKind::Byte(b'Z') | LitKind::Char('Z')), |
| ) | ( |
| Ok(LitKind::Byte(b'0') | LitKind::Char('0')), |
| Ok(LitKind::Byte(b'9') | LitKind::Char('9')), |
| ) |
| ) |
| && !in_external_macro(cx.sess(), span) |
| { |
| span_lint_and_then(cx, ALMOST_COMPLETE_RANGE, span, "almost complete ascii range", |diag| { |
| if let Some((span, sugg)) = sugg { |
| diag.span_suggestion(span, "use an inclusive range", sugg, Applicability::MaybeIncorrect); |
| } |
| }); |
| } |
| } |