Auto merge of #9148 - arieluy:then_some_unwrap_or, r=Jarcho

[rust.git] / clippy_lints / src / zero_div_zero.rs

diff --git a/clippy_lints/src/zero_div_zero.rs b/clippy_lints/src/zero_div_zero.rs
index 0820385e01bb5f68d940a2da8e7f433a137dd55a..50d3c079fe6758c8ff8ff8dce2adeaed804fd6ac 100644 (file)
--- a/clippy_lints/src/zero_div_zero.rs
+++ b/clippy_lints/src/zero_div_zero.rs
@@ -1,25 +1,27 @@
-use crate::consts::{constant_simple, Constant};
-use crate::utils::span_lint_and_help;
+use clippy_utils::consts::{constant_simple, Constant};
+use clippy_utils::diagnostics::span_lint_and_help;
 use if_chain::if_chain;
 use rustc_hir::{BinOpKind, Expr, ExprKind};
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_session::{declare_lint_pass, declare_tool_lint};
 
 declare_clippy_lint! {
-    /// **What it does:** Checks for `0.0 / 0.0`.
+    /// ### What it does
+    /// Checks for `0.0 / 0.0`.
     ///
-    /// **Why is this bad?** It's less readable than `f32::NAN` or `f64::NAN`.
+    /// ### Why is this bad?
+    /// It's less readable than `f32::NAN` or `f64::NAN`.
     ///
-    /// **Known problems:** None.
-    ///
-    /// **Example:**
+    /// ### Example
     /// ```rust
-    /// // Bad
     /// let nan = 0.0f32 / 0.0;
+    /// ```
     ///
-    /// // Good
+    /// Use instead:
+    /// ```rust
     /// let nan = f32::NAN;
     /// ```
+    #[clippy::version = "pre 1.29.0"]
     pub ZERO_DIVIDED_BY_ZERO,
     complexity,
     "usage of `0.0 / 0.0` to obtain NaN instead of `f32::NAN` or `f64::NAN`"
@@ -27,17 +29,17 @@
 
 declare_lint_pass!(ZeroDiv => [ZERO_DIVIDED_BY_ZERO]);
 
-impl<'a, 'tcx> LateLintPass<'a, 'tcx> for ZeroDiv {
-    fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, expr: &'tcx Expr<'_>) {
+impl<'tcx> LateLintPass<'tcx> for ZeroDiv {
+    fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) {
         // check for instances of 0.0/0.0
         if_chain! {
-            if let ExprKind::Binary(ref op, ref left, ref right) = expr.kind;
-            if let BinOpKind::Div = op.node;
+            if let ExprKind::Binary(ref op, left, right) = expr.kind;
+            if op.node == BinOpKind::Div;
             // TODO - constant_simple does not fold many operations involving floats.
             // That's probably fine for this lint - it's pretty unlikely that someone would
             // do something like 0.0/(2.0 - 2.0), but it would be nice to warn on that case too.
-            if let Some(lhs_value) = constant_simple(cx, cx.tables, left);
-            if let Some(rhs_value) = constant_simple(cx, cx.tables, right);
+            if let Some(lhs_value) = constant_simple(cx, cx.typeck_results(), left);
+            if let Some(rhs_value) = constant_simple(cx, cx.typeck_results(), right);
             if Constant::F32(0.0) == lhs_value || Constant::F64(0.0) == lhs_value;
             if Constant::F32(0.0) == rhs_value || Constant::F64(0.0) == rhs_value;
             then {
@@ -55,7 +57,7 @@ fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, expr: &'tcx Expr<'_>) {
                     "constant division of `0.0` with `0.0` will always result in NaN",
                     None,
                     &format!(
-                        "Consider using `{}::NAN` if you would like a constant representing NaN",
+                        "consider using `{}::NAN` if you would like a constant representing NaN",
                         float_type,
                     ),
                 );