Merge branch 'macro-use' into HEAD

[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 888cd33909656cf83684cf14d7b2a74babe6b7d6..7c8af7880ba22b7ec5f7cdbfcc118f2ad1f32eb6 100644 (file)
--- a/clippy_lints/src/zero_div_zero.rs
+++ b/clippy_lints/src/zero_div_zero.rs
@@ -1,7 +1,9 @@
-use consts::{Constant, constant_simple, FloatWidth};
+use crate::consts::{constant_simple, Constant};
 use rustc::lint::*;
+use rustc::{declare_lint, lint_array};
+use if_chain::if_chain;
 use rustc::hir::*;
-use utils::span_help_and_lint;
+use crate::utils::span_help_and_lint;
 
 /// **What it does:** Checks for `0.0 / 0.0`.
 ///
@@ -14,9 +16,9 @@
 /// ```rust
 /// 0.0f32 / 0.0
 /// ```
-declare_lint! {
+declare_clippy_lint! {
     pub ZERO_DIVIDED_BY_ZERO,
-    Warn,
+    complexity,
     "usage of `0.0 / 0.0` to obtain NaN instead of std::f32::NaN or std::f64::NaN"
 }
 
@@ -31,27 +33,35 @@ fn get_lints(&self) -> LintArray {
 impl<'a, 'tcx> LateLintPass<'a, 'tcx> for Pass {
     fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, expr: &'tcx Expr) {
         // check for instances of 0.0/0.0
-        if_let_chain! {[
-            let ExprBinary(ref op, ref left, ref right) = expr.node,
-            let BinOp_::BiDiv = op.node,
+        if_chain! {
+            if let ExprKind::Binary(ref op, ref left, ref right) = expr.node;
+            if let BinOpKind::Div = op.node;
             // 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.
-            let Some(Constant::Float(ref lhs_value, lhs_width)) = constant_simple(cx, left),
-            let Some(Constant::Float(ref rhs_value, rhs_width)) = constant_simple(cx, right),
-            Ok(0.0) == lhs_value.parse(),
-            Ok(0.0) == rhs_value.parse()
-        ], {
-            // since we're about to suggest a use of std::f32::NaN or std::f64::NaN,
-            // match the precision of the literals that are given.
-            let float_type = match (lhs_width, rhs_width) {
-                (FloatWidth::F64, _)
-                | (_, FloatWidth::F64) => "f64",
-                _ => "f32"
-            };
-            span_help_and_lint(cx, ZERO_DIVIDED_BY_ZERO, expr.span,
-                "constant division of 0.0 with 0.0 will always result in NaN",
-                &format!("Consider using `std::{}::NAN` if you would like a constant representing NaN", float_type));
-        }}
+            if let Some(lhs_value) = constant_simple(cx, cx.tables, left);
+            if let Some(rhs_value) = constant_simple(cx, cx.tables, 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 {
+                // since we're about to suggest a use of std::f32::NaN or std::f64::NaN,
+                // match the precision of the literals that are given.
+                let float_type = match (lhs_value, rhs_value) {
+                    (Constant::F64(_), _)
+                    | (_, Constant::F64(_)) => "f64",
+                    _ => "f32"
+                };
+                span_help_and_lint(
+                    cx,
+                    ZERO_DIVIDED_BY_ZERO,
+                    expr.span,
+                    "constant division of 0.0 with 0.0 will always result in NaN",
+                    &format!(
+                        "Consider using `std::{}::NAN` if you would like a constant representing NaN",
+                        float_type,
+                    ),
+                );
+            }
+        }
     }
 }