-use rustc::lint::*;
-use rustc::hir::*;
-use crate::utils::{in_macro, is_range_expression, match_var, span_lint_and_sugg};
+use crate::utils::span_lint_and_sugg;
+use rustc::lint::{EarlyContext, EarlyLintPass, LintArray, LintPass};
+use rustc::{declare_tool_lint, lint_array};
+use rustc_errors::Applicability;
+use syntax::ast::*;
-/// **What it does:** Checks for fields in struct literals where shorthands
-/// could be used.
-///
-/// **Why is this bad?** If the field and variable names are the same,
-/// the field name is redundant.
-///
-/// **Known problems:** None.
-///
-/// **Example:**
-/// ```rust
-/// let bar: u8 = 123;
-///
-/// struct Foo {
-/// bar: u8,
-/// }
-///
-/// let foo = Foo{ bar: bar }
-/// ```
declare_clippy_lint! {
+ /// **What it does:** Checks for fields in struct literals where shorthands
+ /// could be used.
+ ///
+ /// **Why is this bad?** If the field and variable names are the same,
+ /// the field name is redundant.
+ ///
+ /// **Known problems:** None.
+ ///
+ /// **Example:**
+ /// ```rust
+ /// let bar: u8 = 123;
+ ///
+ /// struct Foo {
+ /// bar: u8,
+ /// }
+ ///
+ /// let foo = Foo { bar: bar };
+ /// ```
+ /// the last line can be simplified to
+ /// ```ignore
+ /// let foo = Foo { bar };
+ /// ```
pub REDUNDANT_FIELD_NAMES,
style,
"checks for fields in struct literals where shorthands could be used"
fn get_lints(&self) -> LintArray {
lint_array!(REDUNDANT_FIELD_NAMES)
}
-}
-impl<'a, 'tcx> LateLintPass<'a, 'tcx> for RedundantFieldNames {
- fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, expr: &'tcx Expr) {
- // Ignore all macros including range expressions.
- // They can have redundant field names when expanded.
- // e.g. range expression `start..end` is desugared to `Range { start: start, end: end }`
- if in_macro(expr.span) || is_range_expression(expr.span) {
- return;
- }
+ fn name(&self) -> &'static str {
+ "RedundantFieldNames"
+ }
+}
- if let ExprStruct(_, ref fields, _) = expr.node {
+impl EarlyLintPass for RedundantFieldNames {
+ fn check_expr(&mut self, cx: &EarlyContext<'_>, expr: &Expr) {
+ if let ExprKind::Struct(_, ref fields, _) = expr.node {
for field in fields {
- let name = field.ident.name;
-
- if match_var(&field.expr, name) && !field.is_shorthand {
- span_lint_and_sugg (
- cx,
- REDUNDANT_FIELD_NAMES,
- field.span,
- "redundant field names in struct initialization",
- "replace it with",
- name.to_string()
- );
+ if field.is_shorthand {
+ continue;
+ }
+ if let ExprKind::Path(None, path) = &field.expr.node {
+ if path.segments.len() == 1
+ && path.segments[0].ident == field.ident
+ && path.segments[0].args.is_none()
+ {
+ span_lint_and_sugg(
+ cx,
+ REDUNDANT_FIELD_NAMES,
+ field.span,
+ "redundant field names in struct initialization",
+ "replace it with",
+ field.ident.to_string(),
+ Applicability::MachineApplicable,
+ );
+ }
}
}
}