default_numeric_fallback: Add rustfix tests

Author: Y-Nak

clippy_lints/src/default_numeric_fallback.rs

@@ -1,5 +1,6 @@
 use clippy_utils::diagnostics::span_lint_and_sugg;
-use clippy_utils::source::snippet;
+use clippy_utils::numeric_literal;
+use clippy_utils::source::snippet_opt;
 use if_chain::if_chain;
 use rustc_ast::ast::{LitFloatType, LitIntType, LitKind};
 use rustc_errors::Applicability;
@@ -80,14 +81,23 @@ impl<'a, 'tcx> NumericFallbackVisitor<'a, 'tcx> {
                             LitKind::Int(_, LitIntType::Unsuffixed) | LitKind::Float(_, LitFloatType::Unsuffixed));
                 if !ty_bound.is_numeric();
                 then {
-                    let suffix = match lit_ty.kind() {
-                        ty::Int(IntTy::I32) => "i32",
-                        ty::Float(FloatTy::F64) => "f64",
+                    let (suffix, is_float) = match lit_ty.kind() {
+                        ty::Int(IntTy::I32) => ("i32", false),
+                        ty::Float(FloatTy::F64) => ("f64", true),
                         // Default numeric fallback never results in other types.
                         _ => return,
                     };
 
-                    let sugg = format!("{}_{}", snippet(self.cx, lit.span, ""), suffix);
+                    let src = if let Some(src) = snippet_opt(self.cx, lit.span) {
+                        src
+                    } else {
+                        match lit.node {
+                            LitKind::Int(src, _) => format!("{}", src),
+                            LitKind::Float(src, _) => format!("{}", src),
+                            _ => return,
+                        }
+                    };
+                    let sugg = numeric_literal::format(&src, Some(suffix), is_float);
                     span_lint_and_sugg(
                         self.cx,
                         DEFAULT_NUMERIC_FALLBACK,

tests/ui/default_numeric_fallback_f64.fixed

@@ -0,0 +1,174 @@
+// run-rustfix
+// aux-build:macro_rules.rs
+
+#![warn(clippy::default_numeric_fallback)]
+#![allow(unused)]
+#![allow(clippy::never_loop)]
+#![allow(clippy::no_effect)]
+#![allow(clippy::unnecessary_operation)]
+#![allow(clippy::branches_sharing_code)]
+#![allow(clippy::match_single_binding)]
+
+#[macro_use]
+extern crate macro_rules;
+
+mod basic_expr {
+    fn test() {
+        // Should lint unsuffixed literals typed `f64`.
+        let x = 0.12_f64;
+        let x = [1.0_f64, 2.0_f64, 3.0_f64];
+        let x = if true { (1.0_f64, 2.0_f64) } else { (3.0_f64, 4.0_f64) };
+        let x = match 1.0_f64 {
+            _ => 1.0_f64,
+        };
+
+        // Should NOT lint suffixed literals.
+        let x = 0.12_f64;
+
+        // Should NOT lint literals in init expr if `Local` has a type annotation.
+        let x: f64 = 0.1;
+        let x: [f64; 3] = [1., 2., 3.];
+        let x: (f64, f64) = if true { (1., 2.) } else { (3., 4.) };
+        let x: _ = 1.;
+    }
+}
+
+mod nested_local {
+    fn test() {
+        let x: _ = {
+            // Should lint this because this literal is not bound to any types.
+            let y = 1.0_f64;
+
+            // Should NOT lint this because this literal is bound to `_` of outer `Local`.
+            1.
+        };
+
+        let x: _ = if true {
+            // Should lint this because this literal is not bound to any types.
+            let y = 1.0_f64;
+
+            // Should NOT lint this because this literal is bound to `_` of outer `Local`.
+            1.
+        } else {
+            // Should lint this because this literal is not bound to any types.
+            let y = 1.0_f64;
+
+            // Should NOT lint this because this literal is bound to `_` of outer `Local`.
+            2.
+        };
+    }
+}
+
+mod function_def {
+    fn ret_f64() -> f64 {
+        // Even though the output type is specified,
+        // this unsuffixed literal is linted to reduce heuristics and keep codebase simple.
+        1.0_f64
+    }
+
+    fn test() {
+        // Should lint this because return type is inferred to `f64` and NOT bound to a concrete
+        // type.
+        let f = || -> _ { 1.0_f64 };
+
+        // Even though the output type is specified,
+        // this unsuffixed literal is linted to reduce heuristics and keep codebase simple.
+        let f = || -> f64 { 1.0_f64 };
+    }
+}
+
+mod function_calls {
+    fn concrete_arg(f: f64) {}
+
+    fn generic_arg<T>(t: T) {}
+
+    fn test() {
+        // Should NOT lint this because the argument type is bound to a concrete type.
+        concrete_arg(1.);
+
+        // Should lint this because the argument type is inferred to `f64` and NOT bound to a concrete type.
+        generic_arg(1.0_f64);
+
+        // Should lint this because the argument type is inferred to `f64` and NOT bound to a concrete type.
+        let x: _ = generic_arg(1.0_f64);
+    }
+}
+
+mod struct_ctor {
+    struct ConcreteStruct {
+        x: f64,
+    }
+
+    struct GenericStruct<T> {
+        x: T,
+    }
+
+    fn test() {
+        // Should NOT lint this because the field type is bound to a concrete type.
+        ConcreteStruct { x: 1. };
+
+        // Should lint this because the field type is inferred to `f64` and NOT bound to a concrete type.
+        GenericStruct { x: 1.0_f64 };
+
+        // Should lint this because the field type is inferred to `f64` and NOT bound to a concrete type.
+        let _ = GenericStruct { x: 1.0_f64 };
+    }
+}
+
+mod enum_ctor {
+    enum ConcreteEnum {
+        X(f64),
+    }
+
+    enum GenericEnum<T> {
+        X(T),
+    }
+
+    fn test() {
+        // Should NOT lint this because the field type is bound to a concrete type.
+        ConcreteEnum::X(1.);
+
+        // Should lint this because the field type is inferred to `f64` and NOT bound to a concrete type.
+        GenericEnum::X(1.0_f64);
+    }
+}
+
+mod method_calls {
+    struct StructForMethodCallTest {}
+
+    impl StructForMethodCallTest {
+        fn concrete_arg(&self, f: f64) {}
+
+        fn generic_arg<T>(&self, t: T) {}
+    }
+
+    fn test() {
+        let s = StructForMethodCallTest {};
+
+        // Should NOT lint this because the argument type is bound to a concrete type.
+        s.concrete_arg(1.);
+
+        // Should lint this because the argument type is bound to a concrete type.
+        s.generic_arg(1.0_f64);
+    }
+}
+
+mod in_macro {
+    macro_rules! internal_macro {
+        () => {
+            let x = 22.0_f64;
+        };
+    }
+
+    // Should lint in internal macro.
+    fn internal() {
+        internal_macro!();
+    }
+
+    // Should NOT lint in external macro.
+    fn external() {
+        default_numeric_fallback!();
+    }
+}
+
+fn main() {}

tests/ui/default_numeric_fallback_f64.rs

@@ -1,3 +1,4 @@
+// run-rustfix
 // aux-build:macro_rules.rs
 
 #![warn(clippy::default_numeric_fallback)]
@@ -6,7 +7,6 @@
 #![allow(clippy::no_effect)]
 #![allow(clippy::unnecessary_operation)]
 #![allow(clippy::branches_sharing_code)]
-#![allow(clippy::branches_sharing_code)]
 #![allow(clippy::match_single_binding)]
 
 #[macro_use]

tests/ui/default_numeric_fallback_f64.stderr

@@ -10,133 +10,133 @@ error: default numeric fallback might occur
   --> $DIR/default_numeric_fallback_f64.rs:19:18
    |
 LL |         let x = [1., 2., 3.];
-   |                  ^^ help: consider adding suffix: `1._f64`
+   |                  ^^ help: consider adding suffix: `1.0_f64`
 
 error: default numeric fallback might occur
   --> $DIR/default_numeric_fallback_f64.rs:19:22
    |
 LL |         let x = [1., 2., 3.];
-   |                      ^^ help: consider adding suffix: `2._f64`
+   |                      ^^ help: consider adding suffix: `2.0_f64`
 
 error: default numeric fallback might occur
   --> $DIR/default_numeric_fallback_f64.rs:19:26
    |
 LL |         let x = [1., 2., 3.];
-   |                          ^^ help: consider adding suffix: `3._f64`
+   |                          ^^ help: consider adding suffix: `3.0_f64`
 
 error: default numeric fallback might occur
   --> $DIR/default_numeric_fallback_f64.rs:20:28
    |
 LL |         let x = if true { (1., 2.) } else { (3., 4.) };
-   |                            ^^ help: consider adding suffix: `1._f64`
+   |                            ^^ help: consider adding suffix: `1.0_f64`
 
 error: default numeric fallback might occur
   --> $DIR/default_numeric_fallback_f64.rs:20:32
    |
 LL |         let x = if true { (1., 2.) } else { (3., 4.) };
-   |                                ^^ help: consider adding suffix: `2._f64`
+   |                                ^^ help: consider adding suffix: `2.0_f64`
 
 error: default numeric fallback might occur
   --> $DIR/default_numeric_fallback_f64.rs:20:46
    |
 LL |         let x = if true { (1., 2.) } else { (3., 4.) };
-   |                                              ^^ help: consider adding suffix: `3._f64`
+   |                                              ^^ help: consider adding suffix: `3.0_f64`
 
 error: default numeric fallback might occur
   --> $DIR/default_numeric_fallback_f64.rs:20:50
    |
 LL |         let x = if true { (1., 2.) } else { (3., 4.) };
-   |                                                  ^^ help: consider adding suffix: `4._f64`
+   |                                                  ^^ help: consider adding suffix: `4.0_f64`
 
 error: default numeric fallback might occur
   --> $DIR/default_numeric_fallback_f64.rs:21:23
    |
 LL |         let x = match 1. {
-   |                       ^^ help: consider adding suffix: `1._f64`
+   |                       ^^ help: consider adding suffix: `1.0_f64`
 
 error: default numeric fallback might occur
   --> $DIR/default_numeric_fallback_f64.rs:22:18
    |
 LL |             _ => 1.,
-   |                  ^^ help: consider adding suffix: `1._f64`
+   |                  ^^ help: consider adding suffix: `1.0_f64`
 
 error: default numeric fallback might occur
   --> $DIR/default_numeric_fallback_f64.rs:40:21
    |
 LL |             let y = 1.;
-   |                     ^^ help: consider adding suffix: `1._f64`
+   |                     ^^ help: consider adding suffix: `1.0_f64`
 
 error: default numeric fallback might occur
   --> $DIR/default_numeric_fallback_f64.rs:48:21
    |
 LL |             let y = 1.;
-   |                     ^^ help: consider adding suffix: `1._f64`
+   |                     ^^ help: consider adding suffix: `1.0_f64`
 
 error: default numeric fallback might occur
   --> $DIR/default_numeric_fallback_f64.rs:54:21
    |
 LL |             let y = 1.;
-   |                     ^^ help: consider adding suffix: `1._f64`
+   |                     ^^ help: consider adding suffix: `1.0_f64`
 
 error: default numeric fallback might occur
   --> $DIR/default_numeric_fallback_f64.rs:66:9
    |
 LL |         1.
-   |         ^^ help: consider adding suffix: `1._f64`
+   |         ^^ help: consider adding suffix: `1.0_f64`
 
 error: default numeric fallback might occur
   --> $DIR/default_numeric_fallback_f64.rs:72:27
    |
 LL |         let f = || -> _ { 1. };
-   |                           ^^ help: consider adding suffix: `1._f64`
+   |                           ^^ help: consider adding suffix: `1.0_f64`
 
 error: default numeric fallback might occur
   --> $DIR/default_numeric_fallback_f64.rs:76:29
    |
 LL |         let f = || -> f64 { 1. };
-   |                             ^^ help: consider adding suffix: `1._f64`
+   |                             ^^ help: consider adding suffix: `1.0_f64`
 
 error: default numeric fallback might occur
   --> $DIR/default_numeric_fallback_f64.rs:90:21
    |
 LL |         generic_arg(1.);
-   |                     ^^ help: consider adding suffix: `1._f64`
+   |                     ^^ help: consider adding suffix: `1.0_f64`
 
 error: default numeric fallback might occur
   --> $DIR/default_numeric_fallback_f64.rs:93:32
    |
 LL |         let x: _ = generic_arg(1.);
-   |                                ^^ help: consider adding suffix: `1._f64`
+   |                                ^^ help: consider adding suffix: `1.0_f64`
 
 error: default numeric fallback might occur
   --> $DIR/default_numeric_fallback_f64.rs:111:28
    |
 LL |         GenericStruct { x: 1. };
-   |                            ^^ help: consider adding suffix: `1._f64`
+   |                            ^^ help: consider adding suffix: `1.0_f64`
 
 error: default numeric fallback might occur
   --> $DIR/default_numeric_fallback_f64.rs:114:36
    |
 LL |         let _ = GenericStruct { x: 1. };
-   |                                    ^^ help: consider adding suffix: `1._f64`
+   |                                    ^^ help: consider adding suffix: `1.0_f64`
 
 error: default numeric fallback might occur
   --> $DIR/default_numeric_fallback_f64.rs:132:24
    |
 LL |         GenericEnum::X(1.);
-   |                        ^^ help: consider adding suffix: `1._f64`
+   |                        ^^ help: consider adding suffix: `1.0_f64`
 
 error: default numeric fallback might occur
   --> $DIR/default_numeric_fallback_f64.rs:152:23
    |
 LL |         s.generic_arg(1.);
-   |                       ^^ help: consider adding suffix: `1._f64`
+   |                       ^^ help: consider adding suffix: `1.0_f64`
 
 error: default numeric fallback might occur
   --> $DIR/default_numeric_fallback_f64.rs:159:21
    |
 LL |             let x = 22.;
-   |                     ^^^ help: consider adding suffix: `22._f64`
+   |                     ^^^ help: consider adding suffix: `22.0_f64`
 ...
 LL |         internal_macro!();
    |         ------------------ in this macro invocation