From 4c7bc1785d137cb2de667be58d50b89d252c9707 Mon Sep 17 00:00:00 2001 From: Centri3 <114838443+Centri3@users.noreply.github.com> Date: Sun, 11 Jun 2023 06:21:31 -0500 Subject: [PATCH 1/2] ignore more type aliases in unnecessary_cast ignore more type aliases in unnecessary_cast --- clippy_lints/src/casts/unnecessary_cast.rs | 29 +++++++++++++- tests/ui/unnecessary_cast.fixed | 12 +++++- tests/ui/unnecessary_cast.rs | 12 +++++- tests/ui/unnecessary_cast.stderr | 46 +++++++++++----------- 4 files changed, 72 insertions(+), 27 deletions(-) diff --git a/clippy_lints/src/casts/unnecessary_cast.rs b/clippy_lints/src/casts/unnecessary_cast.rs index d3d80ff41008..41055c168fcb 100644 --- a/clippy_lints/src/casts/unnecessary_cast.rs +++ b/clippy_lints/src/casts/unnecessary_cast.rs @@ -6,13 +6,14 @@ use if_chain::if_chain; use rustc_ast::{LitFloatType, LitIntType, LitKind}; use rustc_errors::Applicability; use rustc_hir::def::Res; -use rustc_hir::{Expr, ExprKind, Lit, QPath, TyKind, UnOp}; +use rustc_hir::{Expr, ExprKind, Lit, Node, Path, QPath, TyKind, UnOp}; use rustc_lint::{LateContext, LintContext}; use rustc_middle::lint::in_external_macro; use rustc_middle::ty::{self, FloatTy, InferTy, Ty}; use super::UNNECESSARY_CAST; +#[expect(clippy::too_many_lines)] pub(super) fn check<'tcx>( cx: &LateContext<'tcx>, expr: &Expr<'tcx>, @@ -58,7 +59,31 @@ pub(super) fn check<'tcx>( } } - // skip non-primitive type cast + // skip cast of local to type alias + if let ExprKind::Cast(inner, ..) = expr.kind + && let ExprKind::Path(qpath) = inner.kind + && let QPath::Resolved(None, Path { res, .. }) = qpath + && let Res::Local(hir_id) = res + && let parent = cx.tcx.hir().get_parent(*hir_id) + && let Node::Local(local) = parent + { + if let Some(ty) = local.ty + && let TyKind::Path(qpath) = ty.kind + && is_ty_alias(&qpath) + { + return false; + } + + if let Some(expr) = local.init + && let ExprKind::Cast(.., cast_to) = expr.kind + && let TyKind::Path(qpath) = cast_to.kind + && is_ty_alias(&qpath) + { + return false; + } + } + + // skip cast to non-primitive type if_chain! { if let ExprKind::Cast(_, cast_to) = expr.kind; if let TyKind::Path(QPath::Resolved(_, path)) = &cast_to.kind; diff --git a/tests/ui/unnecessary_cast.fixed b/tests/ui/unnecessary_cast.fixed index e74476044d9b..f56cee3a364a 100644 --- a/tests/ui/unnecessary_cast.fixed +++ b/tests/ui/unnecessary_cast.fixed @@ -66,12 +66,22 @@ fn main() { foo!(b, f32); foo!(c, f64); + // do not lint cast from cfg-dependant type + let x = 0 as std::ffi::c_ulong; + let y = x as u64; + let x: std::ffi::c_ulong = 0; + let y = x as u64; + // do not lint cast to cfg-dependant type - 1 as std::os::raw::c_char; + let x = 1 as std::os::raw::c_char; + let y = x as u64; // do not lint cast to alias type 1 as I32Alias; &1 as &I32Alias; + // or from + let x: I32Alias = 1; + let y = x as u64; let i8_ptr: *const i8 = &1; let u8_ptr: *const u8 = &1; diff --git a/tests/ui/unnecessary_cast.rs b/tests/ui/unnecessary_cast.rs index a577fd79899e..b4623df69095 100644 --- a/tests/ui/unnecessary_cast.rs +++ b/tests/ui/unnecessary_cast.rs @@ -66,12 +66,22 @@ fn main() { foo!(b, f32); foo!(c, f64); + // do not lint cast from cfg-dependant type + let x = 0 as std::ffi::c_ulong; + let y = x as u64; + let x: std::ffi::c_ulong = 0; + let y = x as u64; + // do not lint cast to cfg-dependant type - 1 as std::os::raw::c_char; + let x = 1 as std::os::raw::c_char; + let y = x as u64; // do not lint cast to alias type 1 as I32Alias; &1 as &I32Alias; + // or from + let x: I32Alias = 1; + let y = x as u64; let i8_ptr: *const i8 = &1; let u8_ptr: *const u8 = &1; diff --git a/tests/ui/unnecessary_cast.stderr b/tests/ui/unnecessary_cast.stderr index 7f748fcf4c2b..b52e5c32c8a9 100644 --- a/tests/ui/unnecessary_cast.stderr +++ b/tests/ui/unnecessary_cast.stderr @@ -91,139 +91,139 @@ LL | uwu::([1u32].as_ptr()) as *const u32; | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `uwu::([1u32].as_ptr())` error: casting integer literal to `f32` is unnecessary - --> $DIR/unnecessary_cast.rs:106:9 + --> $DIR/unnecessary_cast.rs:117:9 | LL | 100 as f32; | ^^^^^^^^^^ help: try: `100_f32` error: casting integer literal to `f64` is unnecessary - --> $DIR/unnecessary_cast.rs:107:9 + --> $DIR/unnecessary_cast.rs:118:9 | LL | 100 as f64; | ^^^^^^^^^^ help: try: `100_f64` error: casting integer literal to `f64` is unnecessary - --> $DIR/unnecessary_cast.rs:108:9 + --> $DIR/unnecessary_cast.rs:119:9 | LL | 100_i32 as f64; | ^^^^^^^^^^^^^^ help: try: `100_f64` error: casting integer literal to `f32` is unnecessary - --> $DIR/unnecessary_cast.rs:109:17 + --> $DIR/unnecessary_cast.rs:120:17 | LL | let _ = -100 as f32; | ^^^^^^^^^^^ help: try: `-100_f32` error: casting integer literal to `f64` is unnecessary - --> $DIR/unnecessary_cast.rs:110:17 + --> $DIR/unnecessary_cast.rs:121:17 | LL | let _ = -100 as f64; | ^^^^^^^^^^^ help: try: `-100_f64` error: casting integer literal to `f64` is unnecessary - --> $DIR/unnecessary_cast.rs:111:17 + --> $DIR/unnecessary_cast.rs:122:17 | LL | let _ = -100_i32 as f64; | ^^^^^^^^^^^^^^^ help: try: `-100_f64` error: casting float literal to `f32` is unnecessary - --> $DIR/unnecessary_cast.rs:112:9 + --> $DIR/unnecessary_cast.rs:123:9 | LL | 100. as f32; | ^^^^^^^^^^^ help: try: `100_f32` error: casting float literal to `f64` is unnecessary - --> $DIR/unnecessary_cast.rs:113:9 + --> $DIR/unnecessary_cast.rs:124:9 | LL | 100. as f64; | ^^^^^^^^^^^ help: try: `100_f64` error: casting integer literal to `u32` is unnecessary - --> $DIR/unnecessary_cast.rs:125:9 + --> $DIR/unnecessary_cast.rs:136:9 | LL | 1 as u32; | ^^^^^^^^ help: try: `1_u32` error: casting integer literal to `i32` is unnecessary - --> $DIR/unnecessary_cast.rs:126:9 + --> $DIR/unnecessary_cast.rs:137:9 | LL | 0x10 as i32; | ^^^^^^^^^^^ help: try: `0x10_i32` error: casting integer literal to `usize` is unnecessary - --> $DIR/unnecessary_cast.rs:127:9 + --> $DIR/unnecessary_cast.rs:138:9 | LL | 0b10 as usize; | ^^^^^^^^^^^^^ help: try: `0b10_usize` error: casting integer literal to `u16` is unnecessary - --> $DIR/unnecessary_cast.rs:128:9 + --> $DIR/unnecessary_cast.rs:139:9 | LL | 0o73 as u16; | ^^^^^^^^^^^ help: try: `0o73_u16` error: casting integer literal to `u32` is unnecessary - --> $DIR/unnecessary_cast.rs:129:9 + --> $DIR/unnecessary_cast.rs:140:9 | LL | 1_000_000_000 as u32; | ^^^^^^^^^^^^^^^^^^^^ help: try: `1_000_000_000_u32` error: casting float literal to `f64` is unnecessary - --> $DIR/unnecessary_cast.rs:131:9 + --> $DIR/unnecessary_cast.rs:142:9 | LL | 1.0 as f64; | ^^^^^^^^^^ help: try: `1.0_f64` error: casting float literal to `f32` is unnecessary - --> $DIR/unnecessary_cast.rs:132:9 + --> $DIR/unnecessary_cast.rs:143:9 | LL | 0.5 as f32; | ^^^^^^^^^^ help: try: `0.5_f32` error: casting integer literal to `i32` is unnecessary - --> $DIR/unnecessary_cast.rs:136:17 + --> $DIR/unnecessary_cast.rs:147:17 | LL | let _ = -1 as i32; | ^^^^^^^^^ help: try: `-1_i32` error: casting float literal to `f32` is unnecessary - --> $DIR/unnecessary_cast.rs:137:17 + --> $DIR/unnecessary_cast.rs:148:17 | LL | let _ = -1.0 as f32; | ^^^^^^^^^^^ help: try: `-1.0_f32` error: casting to the same type is unnecessary (`i32` -> `i32`) - --> $DIR/unnecessary_cast.rs:143:18 + --> $DIR/unnecessary_cast.rs:154:18 | LL | let _ = &(x as i32); | ^^^^^^^^^^ help: try: `{ x }` error: casting integer literal to `i32` is unnecessary - --> $DIR/unnecessary_cast.rs:149:22 + --> $DIR/unnecessary_cast.rs:160:22 | LL | let _: i32 = -(1) as i32; | ^^^^^^^^^^^ help: try: `-1_i32` error: casting integer literal to `i64` is unnecessary - --> $DIR/unnecessary_cast.rs:151:22 + --> $DIR/unnecessary_cast.rs:162:22 | LL | let _: i64 = -(1) as i64; | ^^^^^^^^^^^ help: try: `-1_i64` error: casting float literal to `f64` is unnecessary - --> $DIR/unnecessary_cast.rs:158:22 + --> $DIR/unnecessary_cast.rs:169:22 | LL | let _: f64 = (-8.0 as f64).exp(); | ^^^^^^^^^^^^^ help: try: `(-8.0_f64)` error: casting float literal to `f64` is unnecessary - --> $DIR/unnecessary_cast.rs:160:23 + --> $DIR/unnecessary_cast.rs:171:23 | LL | let _: f64 = -(8.0 as f64).exp(); // should suggest `-8.0_f64.exp()` here not to change code behavior | ^^^^^^^^^^^^ help: try: `8.0_f64` error: casting to the same type is unnecessary (`f32` -> `f32`) - --> $DIR/unnecessary_cast.rs:168:20 + --> $DIR/unnecessary_cast.rs:179:20 | LL | let _num = foo() as f32; | ^^^^^^^^^^^^ help: try: `foo()` From 3822441335ffc761c31e553c42bbfbdacfd8da96 Mon Sep 17 00:00:00 2001 From: Centri3 <114838443+Centri3@users.noreply.github.com> Date: Sun, 11 Jun 2023 07:06:44 -0500 Subject: [PATCH 2/2] Update unnecessary_cast.stderr --- tests/ui/unnecessary_cast.stderr | 46 ++++++++++++++++---------------- 1 file changed, 23 insertions(+), 23 deletions(-) diff --git a/tests/ui/unnecessary_cast.stderr b/tests/ui/unnecessary_cast.stderr index b52e5c32c8a9..618fbd4faaf4 100644 --- a/tests/ui/unnecessary_cast.stderr +++ b/tests/ui/unnecessary_cast.stderr @@ -91,139 +91,139 @@ LL | uwu::([1u32].as_ptr()) as *const u32; | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `uwu::([1u32].as_ptr())` error: casting integer literal to `f32` is unnecessary - --> $DIR/unnecessary_cast.rs:117:9 + --> $DIR/unnecessary_cast.rs:116:9 | LL | 100 as f32; | ^^^^^^^^^^ help: try: `100_f32` error: casting integer literal to `f64` is unnecessary - --> $DIR/unnecessary_cast.rs:118:9 + --> $DIR/unnecessary_cast.rs:117:9 | LL | 100 as f64; | ^^^^^^^^^^ help: try: `100_f64` error: casting integer literal to `f64` is unnecessary - --> $DIR/unnecessary_cast.rs:119:9 + --> $DIR/unnecessary_cast.rs:118:9 | LL | 100_i32 as f64; | ^^^^^^^^^^^^^^ help: try: `100_f64` error: casting integer literal to `f32` is unnecessary - --> $DIR/unnecessary_cast.rs:120:17 + --> $DIR/unnecessary_cast.rs:119:17 | LL | let _ = -100 as f32; | ^^^^^^^^^^^ help: try: `-100_f32` error: casting integer literal to `f64` is unnecessary - --> $DIR/unnecessary_cast.rs:121:17 + --> $DIR/unnecessary_cast.rs:120:17 | LL | let _ = -100 as f64; | ^^^^^^^^^^^ help: try: `-100_f64` error: casting integer literal to `f64` is unnecessary - --> $DIR/unnecessary_cast.rs:122:17 + --> $DIR/unnecessary_cast.rs:121:17 | LL | let _ = -100_i32 as f64; | ^^^^^^^^^^^^^^^ help: try: `-100_f64` error: casting float literal to `f32` is unnecessary - --> $DIR/unnecessary_cast.rs:123:9 + --> $DIR/unnecessary_cast.rs:122:9 | LL | 100. as f32; | ^^^^^^^^^^^ help: try: `100_f32` error: casting float literal to `f64` is unnecessary - --> $DIR/unnecessary_cast.rs:124:9 + --> $DIR/unnecessary_cast.rs:123:9 | LL | 100. as f64; | ^^^^^^^^^^^ help: try: `100_f64` error: casting integer literal to `u32` is unnecessary - --> $DIR/unnecessary_cast.rs:136:9 + --> $DIR/unnecessary_cast.rs:135:9 | LL | 1 as u32; | ^^^^^^^^ help: try: `1_u32` error: casting integer literal to `i32` is unnecessary - --> $DIR/unnecessary_cast.rs:137:9 + --> $DIR/unnecessary_cast.rs:136:9 | LL | 0x10 as i32; | ^^^^^^^^^^^ help: try: `0x10_i32` error: casting integer literal to `usize` is unnecessary - --> $DIR/unnecessary_cast.rs:138:9 + --> $DIR/unnecessary_cast.rs:137:9 | LL | 0b10 as usize; | ^^^^^^^^^^^^^ help: try: `0b10_usize` error: casting integer literal to `u16` is unnecessary - --> $DIR/unnecessary_cast.rs:139:9 + --> $DIR/unnecessary_cast.rs:138:9 | LL | 0o73 as u16; | ^^^^^^^^^^^ help: try: `0o73_u16` error: casting integer literal to `u32` is unnecessary - --> $DIR/unnecessary_cast.rs:140:9 + --> $DIR/unnecessary_cast.rs:139:9 | LL | 1_000_000_000 as u32; | ^^^^^^^^^^^^^^^^^^^^ help: try: `1_000_000_000_u32` error: casting float literal to `f64` is unnecessary - --> $DIR/unnecessary_cast.rs:142:9 + --> $DIR/unnecessary_cast.rs:141:9 | LL | 1.0 as f64; | ^^^^^^^^^^ help: try: `1.0_f64` error: casting float literal to `f32` is unnecessary - --> $DIR/unnecessary_cast.rs:143:9 + --> $DIR/unnecessary_cast.rs:142:9 | LL | 0.5 as f32; | ^^^^^^^^^^ help: try: `0.5_f32` error: casting integer literal to `i32` is unnecessary - --> $DIR/unnecessary_cast.rs:147:17 + --> $DIR/unnecessary_cast.rs:146:17 | LL | let _ = -1 as i32; | ^^^^^^^^^ help: try: `-1_i32` error: casting float literal to `f32` is unnecessary - --> $DIR/unnecessary_cast.rs:148:17 + --> $DIR/unnecessary_cast.rs:147:17 | LL | let _ = -1.0 as f32; | ^^^^^^^^^^^ help: try: `-1.0_f32` error: casting to the same type is unnecessary (`i32` -> `i32`) - --> $DIR/unnecessary_cast.rs:154:18 + --> $DIR/unnecessary_cast.rs:153:18 | LL | let _ = &(x as i32); | ^^^^^^^^^^ help: try: `{ x }` error: casting integer literal to `i32` is unnecessary - --> $DIR/unnecessary_cast.rs:160:22 + --> $DIR/unnecessary_cast.rs:159:22 | LL | let _: i32 = -(1) as i32; | ^^^^^^^^^^^ help: try: `-1_i32` error: casting integer literal to `i64` is unnecessary - --> $DIR/unnecessary_cast.rs:162:22 + --> $DIR/unnecessary_cast.rs:161:22 | LL | let _: i64 = -(1) as i64; | ^^^^^^^^^^^ help: try: `-1_i64` error: casting float literal to `f64` is unnecessary - --> $DIR/unnecessary_cast.rs:169:22 + --> $DIR/unnecessary_cast.rs:168:22 | LL | let _: f64 = (-8.0 as f64).exp(); | ^^^^^^^^^^^^^ help: try: `(-8.0_f64)` error: casting float literal to `f64` is unnecessary - --> $DIR/unnecessary_cast.rs:171:23 + --> $DIR/unnecessary_cast.rs:170:23 | LL | let _: f64 = -(8.0 as f64).exp(); // should suggest `-8.0_f64.exp()` here not to change code behavior | ^^^^^^^^^^^^ help: try: `8.0_f64` error: casting to the same type is unnecessary (`f32` -> `f32`) - --> $DIR/unnecessary_cast.rs:179:20 + --> $DIR/unnecessary_cast.rs:178:20 | LL | let _num = foo() as f32; | ^^^^^^^^^^^^ help: try: `foo()`