From 75637c1edac6db37b3c8aa17ef6b5a91db699a00 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?D=C3=A1niel=20Buga?= Date: Mon, 15 Jun 2020 20:01:18 +0200 Subject: [PATCH] Catch function calls in argument lists, add tests that tuples don't get linted --- clippy_lints/src/methods/mod.rs | 25 ++++++++------ tests/ui/unnecessary_lazy_eval.fixed | 8 ++++- tests/ui/unnecessary_lazy_eval.rs | 8 ++++- tests/ui/unnecessary_lazy_eval.stderr | 48 +++++++++++++-------------- 4 files changed, 52 insertions(+), 37 deletions(-) diff --git a/clippy_lints/src/methods/mod.rs b/clippy_lints/src/methods/mod.rs index ed8eaba75d1a..463ef48f62c4 100644 --- a/clippy_lints/src/methods/mod.rs +++ b/clippy_lints/src/methods/mod.rs @@ -2744,12 +2744,8 @@ fn lint_lazy_eval<'a, 'tcx>( paths.iter().any(|candidate| match_qpath(path, candidate)) } - if let hir::ExprKind::Closure(_, _, eid, _, _) = args[1].kind { - let body = cx.tcx.hir().body(eid); - let ex = &body.value; - let params = &body.params; - - let simplify = match ex.kind { + fn can_simplify(expr: &hir::Expr<'_>, params: &[hir::Param<'_>], variant_calls: bool) -> bool { + match expr.kind { // Closures returning literals can be unconditionally simplified hir::ExprKind::Lit(_) => true, @@ -2767,15 +2763,16 @@ fn lint_lazy_eval<'a, 'tcx>( hir::ExprKind::Field(ref object, _) => !expr_uses_argument(object, params), // Paths can be simplified if the root is not the argument, this also covers None - hir::ExprKind::Path(_) => !expr_uses_argument(ex, params), + hir::ExprKind::Path(_) => !expr_uses_argument(expr, params), // Calls to Some, Ok, Err can be considered literals if they don't derive an argument hir::ExprKind::Call(ref func, ref args) => if_chain! { - if allow_variant_calls; // Disable lint when rules conflict with bind_instead_of_map + if variant_calls; // Disable lint when rules conflict with bind_instead_of_map if let hir::ExprKind::Path(ref path) = func.kind; if match_any_qpath(path, &[&["Some"], &["Ok"], &["Err"]]); then { - !args.iter().any(|arg| expr_uses_argument(arg, params)) + // Recursively check all arguments + args.iter().all(|arg| can_simplify(arg, params, variant_calls)) } else { false } @@ -2784,9 +2781,15 @@ fn lint_lazy_eval<'a, 'tcx>( // For anything more complex than the above, a closure is probably the right solution, // or the case is handled by an other lint _ => false, - }; + } + } - if simplify { + if let hir::ExprKind::Closure(_, _, eid, _, _) = args[1].kind { + let body = cx.tcx.hir().body(eid); + let ex = &body.value; + let params = &body.params; + + if can_simplify(ex, params, allow_variant_calls) { let msg = if is_option { "unnecessary closure used to substitute value for `Option::None`" } else { diff --git a/tests/ui/unnecessary_lazy_eval.fixed b/tests/ui/unnecessary_lazy_eval.fixed index c806cf8dce4d..7f9d90a8569b 100644 --- a/tests/ui/unnecessary_lazy_eval.fixed +++ b/tests/ui/unnecessary_lazy_eval.fixed @@ -25,9 +25,12 @@ fn main() { let ext_arr: [usize; 1] = [2]; let ext_str = SomeStruct { some_field: 10 }; - // Should lint - Option let mut opt = Some(42); let ext_opt = Some(42); + let nested_opt = Some(Some(42)); + let nested_tuple_opt = Some(Some((42, 43))); + + // Should lint - Option let _ = opt.unwrap_or(2); let _ = opt.unwrap_or(astronomers_pi); let _ = opt.unwrap_or(ext_str.some_field); @@ -56,6 +59,9 @@ fn main() { // Should not lint - Option let _ = opt.unwrap_or_else(|| ext_str.return_some_field()); + let _ = nested_opt.unwrap_or_else(|| Some(some_call())); + let _ = nested_tuple_opt.unwrap_or_else(|| Some((1, 2))); + let _ = nested_tuple_opt.unwrap_or_else(|| Some((some_call(), some_call()))); let _ = opt.or_else(some_call); let _ = opt.or_else(|| some_call()); let _: Result = opt.ok_or_else(|| some_call()); diff --git a/tests/ui/unnecessary_lazy_eval.rs b/tests/ui/unnecessary_lazy_eval.rs index dfc6d3ba5735..ca8238d6dcfa 100644 --- a/tests/ui/unnecessary_lazy_eval.rs +++ b/tests/ui/unnecessary_lazy_eval.rs @@ -25,9 +25,12 @@ fn main() { let ext_arr: [usize; 1] = [2]; let ext_str = SomeStruct { some_field: 10 }; - // Should lint - Option let mut opt = Some(42); let ext_opt = Some(42); + let nested_opt = Some(Some(42)); + let nested_tuple_opt = Some(Some((42, 43))); + + // Should lint - Option let _ = opt.unwrap_or_else(|| 2); let _ = opt.unwrap_or_else(|| astronomers_pi); let _ = opt.unwrap_or_else(|| ext_str.some_field); @@ -56,6 +59,9 @@ fn main() { // Should not lint - Option let _ = opt.unwrap_or_else(|| ext_str.return_some_field()); + let _ = nested_opt.unwrap_or_else(|| Some(some_call())); + let _ = nested_tuple_opt.unwrap_or_else(|| Some((1, 2))); + let _ = nested_tuple_opt.unwrap_or_else(|| Some((some_call(), some_call()))); let _ = opt.or_else(some_call); let _ = opt.or_else(|| some_call()); let _: Result = opt.ok_or_else(|| some_call()); diff --git a/tests/ui/unnecessary_lazy_eval.stderr b/tests/ui/unnecessary_lazy_eval.stderr index 155918175405..b8ec654e5c7b 100644 --- a/tests/ui/unnecessary_lazy_eval.stderr +++ b/tests/ui/unnecessary_lazy_eval.stderr @@ -1,5 +1,5 @@ error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:31:13 + --> $DIR/unnecessary_lazy_eval.rs:34:13 | LL | let _ = opt.unwrap_or_else(|| 2); | ^^^^^^^^^^^^^^^^^^^^^^^^ help: Use `unwrap_or` instead: `opt.unwrap_or(2)` @@ -7,139 +7,139 @@ LL | let _ = opt.unwrap_or_else(|| 2); = note: `-D clippy::unnecessary-lazy-evaluation` implied by `-D warnings` error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:32:13 + --> $DIR/unnecessary_lazy_eval.rs:35:13 | LL | let _ = opt.unwrap_or_else(|| astronomers_pi); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: Use `unwrap_or` instead: `opt.unwrap_or(astronomers_pi)` error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:33:13 + --> $DIR/unnecessary_lazy_eval.rs:36:13 | LL | let _ = opt.unwrap_or_else(|| ext_str.some_field); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: Use `unwrap_or` instead: `opt.unwrap_or(ext_str.some_field)` error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:34:13 + --> $DIR/unnecessary_lazy_eval.rs:37:13 | LL | let _ = opt.unwrap_or_else(|| ext_arr[0]); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: Use `unwrap_or` instead: `opt.unwrap_or(ext_arr[0])` error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:35:13 + --> $DIR/unnecessary_lazy_eval.rs:38:13 | LL | let _ = opt.and_then(|_| ext_opt); | ^^^^^^^^^^^^^^^^^^^^^^^^^ help: Use `and` instead: `opt.and(ext_opt)` error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:36:13 + --> $DIR/unnecessary_lazy_eval.rs:39:13 | LL | let _ = opt.or_else(|| ext_opt); | ^^^^^^^^^^^^^^^^^^^^^^^ help: Use `or` instead: `opt.or(ext_opt)` error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:37:13 + --> $DIR/unnecessary_lazy_eval.rs:40:13 | LL | let _ = opt.or_else(|| None); | ^^^^^^^^^^^^^^^^^^^^ help: Use `or` instead: `opt.or(None)` error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:38:13 + --> $DIR/unnecessary_lazy_eval.rs:41:13 | LL | let _ = opt.get_or_insert_with(|| 2); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: Use `get_or_insert` instead: `opt.get_or_insert(2)` error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:39:13 + --> $DIR/unnecessary_lazy_eval.rs:42:13 | LL | let _ = opt.ok_or_else(|| 2); | ^^^^^^^^^^^^^^^^^^^^ help: Use `ok_or` instead: `opt.ok_or(2)` error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:40:13 + --> $DIR/unnecessary_lazy_eval.rs:43:13 | LL | let _ = opt.ok_or_else(|| ext_arr[0]); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: Use `ok_or` instead: `opt.ok_or(ext_arr[0])` error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:43:13 + --> $DIR/unnecessary_lazy_eval.rs:46:13 | LL | let _ = Some(10).unwrap_or_else(|| 2); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: Use `unwrap_or` instead: `Some(10).unwrap_or(2)` error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:44:13 + --> $DIR/unnecessary_lazy_eval.rs:47:13 | LL | let _ = Some(10).and_then(|_| ext_opt); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: Use `and` instead: `Some(10).and(ext_opt)` error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:45:28 + --> $DIR/unnecessary_lazy_eval.rs:48:28 | LL | let _: Option = None.or_else(|| ext_opt); | ^^^^^^^^^^^^^^^^^^^^^^^^ help: Use `or` instead: `None.or(ext_opt)` error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:46:13 + --> $DIR/unnecessary_lazy_eval.rs:49:13 | LL | let _ = None.get_or_insert_with(|| 2); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: Use `get_or_insert` instead: `None.get_or_insert(2)` error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:47:35 + --> $DIR/unnecessary_lazy_eval.rs:50:35 | LL | let _: Result = None.ok_or_else(|| 2); | ^^^^^^^^^^^^^^^^^^^^^ help: Use `ok_or` instead: `None.ok_or(2)` error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:48:28 + --> $DIR/unnecessary_lazy_eval.rs:51:28 | LL | let _: Option = None.or_else(|| None); | ^^^^^^^^^^^^^^^^^^^^^ help: Use `or` instead: `None.or(None)` error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:51:13 + --> $DIR/unnecessary_lazy_eval.rs:54:13 | LL | let _ = deep.0.unwrap_or_else(|| 2); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: Use `unwrap_or` instead: `deep.0.unwrap_or(2)` error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:52:13 + --> $DIR/unnecessary_lazy_eval.rs:55:13 | LL | let _ = deep.0.and_then(|_| ext_opt); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: Use `and` instead: `deep.0.and(ext_opt)` error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:53:13 + --> $DIR/unnecessary_lazy_eval.rs:56:13 | LL | let _ = deep.0.or_else(|| None); | ^^^^^^^^^^^^^^^^^^^^^^^ help: Use `or` instead: `deep.0.or(None)` error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:54:13 + --> $DIR/unnecessary_lazy_eval.rs:57:13 | LL | let _ = deep.0.get_or_insert_with(|| 2); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: Use `get_or_insert` instead: `deep.0.get_or_insert(2)` error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:55:13 + --> $DIR/unnecessary_lazy_eval.rs:58:13 | LL | let _ = deep.0.ok_or_else(|| 2); | ^^^^^^^^^^^^^^^^^^^^^^^ help: Use `ok_or` instead: `deep.0.ok_or(2)` error: unnecessary closure used to substitute value for `Result::Err` - --> $DIR/unnecessary_lazy_eval.rs:78:13 + --> $DIR/unnecessary_lazy_eval.rs:84:13 | LL | let _ = res2.unwrap_or_else(|_| 2); | ^^^^^^^^^^^^^^^^^^^^^^^^^^ help: Use `unwrap_or` instead: `res2.unwrap_or(2)` error: unnecessary closure used to substitute value for `Result::Err` - --> $DIR/unnecessary_lazy_eval.rs:79:13 + --> $DIR/unnecessary_lazy_eval.rs:85:13 | LL | let _ = res2.unwrap_or_else(|_| astronomers_pi); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: Use `unwrap_or` instead: `res2.unwrap_or(astronomers_pi)` error: unnecessary closure used to substitute value for `Result::Err` - --> $DIR/unnecessary_lazy_eval.rs:80:13 + --> $DIR/unnecessary_lazy_eval.rs:86:13 | LL | let _ = res2.unwrap_or_else(|_| ext_str.some_field); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: Use `unwrap_or` instead: `res2.unwrap_or(ext_str.some_field)`