From 307b8cd82537b5ac46da2f04cced4e4362835757 Mon Sep 17 00:00:00 2001
From: Alex Macleod <alex@macleod.io>
Date: Mon, 6 Jun 2022 15:09:37 +0000
Subject: [PATCH] Lint simple expressions in manual_filter_map, manual_find_map
---
clippy_lints/src/methods/filter_map.rs | 107 +++++++++----------
tests/ui/manual_filter_map.fixed | 34 +++++++
tests/ui/manual_filter_map.rs | 38 +++++++
tests/ui/manual_filter_map.stderr | 120 ++++++++++++++++++++--
tests/ui/manual_find_map.fixed | 37 +++++++
tests/ui/manual_find_map.rs | 41 ++++++++
tests/ui/manual_find_map.stderr | 136 +++++++++++++++++++++++--
7 files changed, 440 insertions(+), 73 deletions(-)
diff --git a/clippy_lints/src/methods/filter_map.rs b/clippy_lints/src/methods/filter_map.rs
index 58c3e52e138..b694a5a7948 100644
--- a/clippy_lints/src/methods/filter_map.rs
+++ b/clippy_lints/src/methods/filter_map.rs
@@ -8,6 +8,7 @@ use rustc_hir as hir;
use rustc_hir::def::Res;
use rustc_hir::{Expr, ExprKind, PatKind, PathSegment, QPath, UnOp};
use rustc_lint::LateContext;
+use rustc_middle::ty::adjustment::Adjust;
use rustc_span::source_map::Span;
use rustc_span::symbol::{sym, Symbol};
use std::borrow::Cow;
@@ -49,35 +50,18 @@ fn is_option_filter_map<'tcx>(cx: &LateContext<'tcx>, filter_arg: &hir::Expr<'_>
is_method(cx, map_arg, sym::unwrap) && is_method(cx, filter_arg, sym!(is_some))
}
-/// lint use of `filter().map()` for `Iterators`
-fn lint_filter_some_map_unwrap(
+/// is `filter(|x| x.is_some()).map(|x| x.unwrap())`
+fn is_filter_some_map_unwrap(
cx: &LateContext<'_>,
expr: &hir::Expr<'_>,
filter_recv: &hir::Expr<'_>,
filter_arg: &hir::Expr<'_>,
map_arg: &hir::Expr<'_>,
- target_span: Span,
- methods_span: Span,
-) {
+) -> bool {
let iterator = is_trait_method(cx, expr, sym::Iterator);
let option = is_type_diagnostic_item(cx, cx.typeck_results().expr_ty(filter_recv), sym::Option);
- if (iterator || option) && is_option_filter_map(cx, filter_arg, map_arg) {
- let msg = "`filter` for `Some` followed by `unwrap`";
- let help = "consider using `flatten` instead";
- let sugg = format!(
- "{}",
- reindent_multiline(Cow::Borrowed("flatten()"), true, indent_of(cx, target_span),)
- );
- span_lint_and_sugg(
- cx,
- OPTION_FILTER_MAP,
- methods_span,
- msg,
- help,
- sugg,
- Applicability::MachineApplicable,
- );
- }
+
+ (iterator || option) && is_option_filter_map(cx, filter_arg, map_arg)
}
/// lint use of `filter().map()` or `find().map()` for `Iterators`
@@ -93,15 +77,20 @@ pub(super) fn check<'tcx>(
map_span: Span,
is_find: bool,
) {
- lint_filter_some_map_unwrap(
- cx,
- expr,
- filter_recv,
- filter_arg,
- map_arg,
- map_span,
- filter_span.with_hi(expr.span.hi()),
- );
+ if is_filter_some_map_unwrap(cx, expr, filter_recv, filter_arg, map_arg) {
+ span_lint_and_sugg(
+ cx,
+ OPTION_FILTER_MAP,
+ filter_span.with_hi(expr.span.hi()),
+ "`filter` for `Some` followed by `unwrap`",
+ "consider using `flatten` instead",
+ reindent_multiline(Cow::Borrowed("flatten()"), true, indent_of(cx, map_span)).into_owned(),
+ Applicability::MachineApplicable,
+ );
+
+ return;
+ }
+
if_chain! {
if is_trait_method(cx, map_recv, sym::Iterator);
@@ -118,7 +107,7 @@ pub(super) fn check<'tcx>(
// closure ends with is_some() or is_ok()
if let PatKind::Binding(_, filter_param_id, _, None) = filter_pat.kind;
if let ExprKind::MethodCall(path, [filter_arg], _) = filter_body.value.kind;
- if let Some(opt_ty) = cx.typeck_results().expr_ty(filter_arg).ty_adt_def();
+ if let Some(opt_ty) = cx.typeck_results().expr_ty(filter_arg).peel_refs().ty_adt_def();
if let Some(is_result) = if cx.tcx.is_diagnostic_item(sym::Option, opt_ty.did()) {
Some(false)
} else if cx.tcx.is_diagnostic_item(sym::Result, opt_ty.did()) {
@@ -137,6 +126,19 @@ pub(super) fn check<'tcx>(
if let ExprKind::MethodCall(seg, [map_arg, ..], _) = map_body.value.kind;
if matches!(seg.ident.name, sym::expect | sym::unwrap | sym::unwrap_or);
+ // .filter(..).map(|y| f(y).copied().unwrap())
+ // ~~~~
+ let map_arg_peeled = match map_arg.kind {
+ ExprKind::MethodCall(method, [original_arg], _) if acceptable_methods(method) => {
+ original_arg
+ },
+ _ => map_arg,
+ };
+
+ // .filter(|x| x.is_some()).map(|y| y[.acceptable_method()].unwrap())
+ let simple_equal = path_to_local_id(filter_arg, filter_param_id)
+ && path_to_local_id(map_arg_peeled, map_param_id);
+
let eq_fallback = |a: &Expr<'_>, b: &Expr<'_>| {
// in `filter(|x| ..)`, replace `*x` with `x`
let a_path = if_chain! {
@@ -145,25 +147,12 @@ pub(super) fn check<'tcx>(
then { expr_path } else { a }
};
// let the filter closure arg and the map closure arg be equal
- if_chain! {
- if path_to_local_id(a_path, filter_param_id);
- if path_to_local_id(b, map_param_id);
- if cx.typeck_results().expr_ty_adjusted(a) == cx.typeck_results().expr_ty_adjusted(b);
- then {
- return true;
- }
- }
- false
- };
-
- if match map_arg.kind {
- ExprKind::MethodCall(method, [original_arg], _) => {
- acceptable_methods(method)
- && SpanlessEq::new(cx).expr_fallback(eq_fallback).eq_expr(filter_arg, original_arg)
- },
- _ => SpanlessEq::new(cx).expr_fallback(eq_fallback).eq_expr(filter_arg, map_arg)
+ path_to_local_id(a_path, filter_param_id)
+ && path_to_local_id(b, map_param_id)
+ && cx.typeck_results().expr_ty_adjusted(a) == cx.typeck_results().expr_ty_adjusted(b)
};
+ if simple_equal || SpanlessEq::new(cx).expr_fallback(eq_fallback).eq_expr(filter_arg, map_arg_peeled);
then {
let span = filter_span.with_hi(expr.span.hi());
let (filter_name, lint) = if is_find {
@@ -171,10 +160,22 @@ pub(super) fn check<'tcx>(
} else {
("filter", MANUAL_FILTER_MAP)
};
- let msg = format!("`{}(..).map(..)` can be simplified as `{0}_map(..)`", filter_name);
- let to_opt = if is_result { ".ok()" } else { "" };
- let sugg = format!("{}_map(|{}| {}{})", filter_name, map_param_ident,
- snippet(cx, map_arg.span, ".."), to_opt);
+ let msg = format!("`{filter_name}(..).map(..)` can be simplified as `{filter_name}_map(..)`");
+ let (to_opt, deref) = if is_result {
+ (".ok()", String::new())
+ } else {
+ let derefs = cx.typeck_results()
+ .expr_adjustments(map_arg)
+ .iter()
+ .filter(|adj| matches!(adj.kind, Adjust::Deref(_)))
+ .count();
+
+ ("", "*".repeat(derefs))
+ };
+ let sugg = format!(
+ "{filter_name}_map(|{map_param_ident}| {deref}{}{to_opt})",
+ snippet(cx, map_arg.span, ".."),
+ );
span_lint_and_sugg(cx, lint, span, &msg, "try", sugg, Applicability::MachineApplicable);
}
}
diff --git a/tests/ui/manual_filter_map.fixed b/tests/ui/manual_filter_map.fixed
index de0d8614889..4936dc9b2e0 100644
--- a/tests/ui/manual_filter_map.fixed
+++ b/tests/ui/manual_filter_map.fixed
@@ -12,6 +12,32 @@ fn main() {
// is_ok(), unwrap_or()
let _ = (0..).filter_map(|a| to_res(a).ok());
+
+ let _ = (1..5)
+ .filter_map(|y| *to_ref(to_opt(y)));
+ let _ = (1..5)
+ .filter_map(|y| *to_ref(to_opt(y)));
+
+ let _ = (1..5)
+ .filter_map(|y| to_ref(to_res(y)).ok());
+ let _ = (1..5)
+ .filter_map(|y| to_ref(to_res(y)).ok());
+}
+
+#[rustfmt::skip]
+fn simple_equal() {
+ iter::<Option<&u8>>().find_map(|x| x.cloned());
+ iter::<&Option<&u8>>().find_map(|x| x.cloned());
+ iter::<&Option<String>>().find_map(|x| x.as_deref());
+ iter::<Option<&String>>().find_map(|y| to_ref(y).cloned());
+
+ iter::<Result<u8, ()>>().find_map(|x| x.ok());
+ iter::<&Result<u8, ()>>().find_map(|x| x.ok());
+ iter::<&&Result<u8, ()>>().find_map(|x| x.ok());
+ iter::<Result<&u8, ()>>().find_map(|x| x.cloned().ok());
+ iter::<&Result<&u8, ()>>().find_map(|x| x.cloned().ok());
+ iter::<&Result<String, ()>>().find_map(|x| x.as_deref().ok());
+ iter::<Result<&String, ()>>().find_map(|y| to_ref(y).cloned().ok());
}
fn no_lint() {
@@ -28,6 +54,10 @@ fn no_lint() {
.map(|a| to_opt(a).unwrap());
}
+fn iter<T>() -> impl Iterator<Item = T> {
+ std::iter::empty()
+}
+
fn to_opt<T>(_: T) -> Option<T> {
unimplemented!()
}
@@ -36,6 +66,10 @@ fn to_res<T>(_: T) -> Result<T, ()> {
unimplemented!()
}
+fn to_ref<'a, T>(_: T) -> &'a T {
+ unimplemented!()
+}
+
struct Issue8920<'a> {
option_field: Option<String>,
result_field: Result<String, ()>,
diff --git a/tests/ui/manual_filter_map.rs b/tests/ui/manual_filter_map.rs
index bd6516f038b..8c67e827b4c 100644
--- a/tests/ui/manual_filter_map.rs
+++ b/tests/ui/manual_filter_map.rs
@@ -12,6 +12,36 @@ fn main() {
// is_ok(), unwrap_or()
let _ = (0..).filter(|&n| to_res(n).is_ok()).map(|a| to_res(a).unwrap_or(1));
+
+ let _ = (1..5)
+ .filter(|&x| to_ref(to_opt(x)).is_some())
+ .map(|y| to_ref(to_opt(y)).unwrap());
+ let _ = (1..5)
+ .filter(|x| to_ref(to_opt(*x)).is_some())
+ .map(|y| to_ref(to_opt(y)).unwrap());
+
+ let _ = (1..5)
+ .filter(|&x| to_ref(to_res(x)).is_ok())
+ .map(|y| to_ref(to_res(y)).unwrap());
+ let _ = (1..5)
+ .filter(|x| to_ref(to_res(*x)).is_ok())
+ .map(|y| to_ref(to_res(y)).unwrap());
+}
+
+#[rustfmt::skip]
+fn simple_equal() {
+ iter::<Option<&u8>>().find(|x| x.is_some()).map(|x| x.cloned().unwrap());
+ iter::<&Option<&u8>>().find(|x| x.is_some()).map(|x| x.cloned().unwrap());
+ iter::<&Option<String>>().find(|x| x.is_some()).map(|x| x.as_deref().unwrap());
+ iter::<Option<&String>>().find(|&x| to_ref(x).is_some()).map(|y| to_ref(y).cloned().unwrap());
+
+ iter::<Result<u8, ()>>().find(|x| x.is_ok()).map(|x| x.unwrap());
+ iter::<&Result<u8, ()>>().find(|x| x.is_ok()).map(|x| x.unwrap());
+ iter::<&&Result<u8, ()>>().find(|x| x.is_ok()).map(|x| x.unwrap());
+ iter::<Result<&u8, ()>>().find(|x| x.is_ok()).map(|x| x.cloned().unwrap());
+ iter::<&Result<&u8, ()>>().find(|x| x.is_ok()).map(|x| x.cloned().unwrap());
+ iter::<&Result<String, ()>>().find(|x| x.is_ok()).map(|x| x.as_deref().unwrap());
+ iter::<Result<&String, ()>>().find(|&x| to_ref(x).is_ok()).map(|y| to_ref(y).cloned().unwrap());
}
fn no_lint() {
@@ -28,6 +58,10 @@ fn no_lint() {
.map(|a| to_opt(a).unwrap());
}
+fn iter<T>() -> impl Iterator<Item = T> {
+ std::iter::empty()
+}
+
fn to_opt<T>(_: T) -> Option<T> {
unimplemented!()
}
@@ -36,6 +70,10 @@ fn to_res<T>(_: T) -> Result<T, ()> {
unimplemented!()
}
+fn to_ref<'a, T>(_: T) -> &'a T {
+ unimplemented!()
+}
+
struct Issue8920<'a> {
option_field: Option<String>,
result_field: Result<String, ()>,
diff --git a/tests/ui/manual_filter_map.stderr b/tests/ui/manual_filter_map.stderr
index 465f1b19110..6e5bbe8f2aa 100644
--- a/tests/ui/manual_filter_map.stderr
+++ b/tests/ui/manual_filter_map.stderr
@@ -19,7 +19,107 @@ LL | let _ = (0..).filter(|&n| to_res(n).is_ok()).map(|a| to_res(a).unwrap_o
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `filter_map(|a| to_res(a).ok())`
error: `filter(..).map(..)` can be simplified as `filter_map(..)`
- --> $DIR/manual_filter_map.rs:54:10
+ --> $DIR/manual_filter_map.rs:17:10
+ |
+LL | .filter(|&x| to_ref(to_opt(x)).is_some())
+ | __________^
+LL | | .map(|y| to_ref(to_opt(y)).unwrap());
+ | |____________________________________________^ help: try: `filter_map(|y| *to_ref(to_opt(y)))`
+
+error: `filter(..).map(..)` can be simplified as `filter_map(..)`
+ --> $DIR/manual_filter_map.rs:20:10
+ |
+LL | .filter(|x| to_ref(to_opt(*x)).is_some())
+ | __________^
+LL | | .map(|y| to_ref(to_opt(y)).unwrap());
+ | |____________________________________________^ help: try: `filter_map(|y| *to_ref(to_opt(y)))`
+
+error: `filter(..).map(..)` can be simplified as `filter_map(..)`
+ --> $DIR/manual_filter_map.rs:24:10
+ |
+LL | .filter(|&x| to_ref(to_res(x)).is_ok())
+ | __________^
+LL | | .map(|y| to_ref(to_res(y)).unwrap());
+ | |____________________________________________^ help: try: `filter_map(|y| to_ref(to_res(y)).ok())`
+
+error: `filter(..).map(..)` can be simplified as `filter_map(..)`
+ --> $DIR/manual_filter_map.rs:27:10
+ |
+LL | .filter(|x| to_ref(to_res(*x)).is_ok())
+ | __________^
+LL | | .map(|y| to_ref(to_res(y)).unwrap());
+ | |____________________________________________^ help: try: `filter_map(|y| to_ref(to_res(y)).ok())`
+
+error: `find(..).map(..)` can be simplified as `find_map(..)`
+ --> $DIR/manual_filter_map.rs:33:27
+ |
+LL | iter::<Option<&u8>>().find(|x| x.is_some()).map(|x| x.cloned().unwrap());
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `find_map(|x| x.cloned())`
+ |
+ = note: `-D clippy::manual-find-map` implied by `-D warnings`
+
+error: `find(..).map(..)` can be simplified as `find_map(..)`
+ --> $DIR/manual_filter_map.rs:34:28
+ |
+LL | iter::<&Option<&u8>>().find(|x| x.is_some()).map(|x| x.cloned().unwrap());
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `find_map(|x| x.cloned())`
+
+error: `find(..).map(..)` can be simplified as `find_map(..)`
+ --> $DIR/manual_filter_map.rs:35:31
+ |
+LL | iter::<&Option<String>>().find(|x| x.is_some()).map(|x| x.as_deref().unwrap());
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `find_map(|x| x.as_deref())`
+
+error: `find(..).map(..)` can be simplified as `find_map(..)`
+ --> $DIR/manual_filter_map.rs:36:31
+ |
+LL | iter::<Option<&String>>().find(|&x| to_ref(x).is_some()).map(|y| to_ref(y).cloned().unwrap());
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `find_map(|y| to_ref(y).cloned())`
+
+error: `find(..).map(..)` can be simplified as `find_map(..)`
+ --> $DIR/manual_filter_map.rs:38:30
+ |
+LL | iter::<Result<u8, ()>>().find(|x| x.is_ok()).map(|x| x.unwrap());
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `find_map(|x| x.ok())`
+
+error: `find(..).map(..)` can be simplified as `find_map(..)`
+ --> $DIR/manual_filter_map.rs:39:31
+ |
+LL | iter::<&Result<u8, ()>>().find(|x| x.is_ok()).map(|x| x.unwrap());
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `find_map(|x| x.ok())`
+
+error: `find(..).map(..)` can be simplified as `find_map(..)`
+ --> $DIR/manual_filter_map.rs:40:32
+ |
+LL | iter::<&&Result<u8, ()>>().find(|x| x.is_ok()).map(|x| x.unwrap());
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `find_map(|x| x.ok())`
+
+error: `find(..).map(..)` can be simplified as `find_map(..)`
+ --> $DIR/manual_filter_map.rs:41:31
+ |
+LL | iter::<Result<&u8, ()>>().find(|x| x.is_ok()).map(|x| x.cloned().unwrap());
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `find_map(|x| x.cloned().ok())`
+
+error: `find(..).map(..)` can be simplified as `find_map(..)`
+ --> $DIR/manual_filter_map.rs:42:32
+ |
+LL | iter::<&Result<&u8, ()>>().find(|x| x.is_ok()).map(|x| x.cloned().unwrap());
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `find_map(|x| x.cloned().ok())`
+
+error: `find(..).map(..)` can be simplified as `find_map(..)`
+ --> $DIR/manual_filter_map.rs:43:35
+ |
+LL | iter::<&Result<String, ()>>().find(|x| x.is_ok()).map(|x| x.as_deref().unwrap());
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `find_map(|x| x.as_deref().ok())`
+
+error: `find(..).map(..)` can be simplified as `find_map(..)`
+ --> $DIR/manual_filter_map.rs:44:35
+ |
+LL | iter::<Result<&String, ()>>().find(|&x| to_ref(x).is_ok()).map(|y| to_ref(y).cloned().unwrap());
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `find_map(|y| to_ref(y).cloned().ok())`
+
+error: `filter(..).map(..)` can be simplified as `filter_map(..)`
+ --> $DIR/manual_filter_map.rs:92:10
|
LL | .filter(|f| f.option_field.is_some())
| __________^
@@ -27,7 +127,7 @@ LL | | .map(|f| f.option_field.clone().unwrap());
| |_________________________________________________^ help: try: `filter_map(|f| f.option_field.clone())`
error: `filter(..).map(..)` can be simplified as `filter_map(..)`
- --> $DIR/manual_filter_map.rs:59:10
+ --> $DIR/manual_filter_map.rs:97:10
|
LL | .filter(|f| f.ref_field.is_some())
| __________^
@@ -35,7 +135,7 @@ LL | | .map(|f| f.ref_field.cloned().unwrap());
| |_______________________________________________^ help: try: `filter_map(|f| f.ref_field.cloned())`
error: `filter(..).map(..)` can be simplified as `filter_map(..)`
- --> $DIR/manual_filter_map.rs:64:10
+ --> $DIR/manual_filter_map.rs:102:10
|
LL | .filter(|f| f.ref_field.is_some())
| __________^
@@ -43,7 +143,7 @@ LL | | .map(|f| f.ref_field.copied().unwrap());
| |_______________________________________________^ help: try: `filter_map(|f| f.ref_field.copied())`
error: `filter(..).map(..)` can be simplified as `filter_map(..)`
- --> $DIR/manual_filter_map.rs:69:10
+ --> $DIR/manual_filter_map.rs:107:10
|
LL | .filter(|f| f.result_field.is_ok())
| __________^
@@ -51,7 +151,7 @@ LL | | .map(|f| f.result_field.clone().unwrap());
| |_________________________________________________^ help: try: `filter_map(|f| f.result_field.clone().ok())`
error: `filter(..).map(..)` can be simplified as `filter_map(..)`
- --> $DIR/manual_filter_map.rs:74:10
+ --> $DIR/manual_filter_map.rs:112:10
|
LL | .filter(|f| f.result_field.is_ok())
| __________^
@@ -59,7 +159,7 @@ LL | | .map(|f| f.result_field.as_ref().unwrap());
| |__________________________________________________^ help: try: `filter_map(|f| f.result_field.as_ref().ok())`
error: `filter(..).map(..)` can be simplified as `filter_map(..)`
- --> $DIR/manual_filter_map.rs:79:10
+ --> $DIR/manual_filter_map.rs:117:10
|
LL | .filter(|f| f.result_field.is_ok())
| __________^
@@ -67,7 +167,7 @@ LL | | .map(|f| f.result_field.as_deref().unwrap());
| |____________________________________________________^ help: try: `filter_map(|f| f.result_field.as_deref().ok())`
error: `filter(..).map(..)` can be simplified as `filter_map(..)`
- --> $DIR/manual_filter_map.rs:84:10
+ --> $DIR/manual_filter_map.rs:122:10
|
LL | .filter(|f| f.result_field.is_ok())
| __________^
@@ -75,7 +175,7 @@ LL | | .map(|f| f.result_field.as_mut().unwrap());
| |__________________________________________________^ help: try: `filter_map(|f| f.result_field.as_mut().ok())`
error: `filter(..).map(..)` can be simplified as `filter_map(..)`
- --> $DIR/manual_filter_map.rs:89:10
+ --> $DIR/manual_filter_map.rs:127:10
|
LL | .filter(|f| f.result_field.is_ok())
| __________^
@@ -83,12 +183,12 @@ LL | | .map(|f| f.result_field.as_deref_mut().unwrap());
| |________________________________________________________^ help: try: `filter_map(|f| f.result_field.as_deref_mut().ok())`
error: `filter(..).map(..)` can be simplified as `filter_map(..)`
- --> $DIR/manual_filter_map.rs:94:10
+ --> $DIR/manual_filter_map.rs:132:10
|
LL | .filter(|f| f.result_field.is_ok())
| __________^
LL | | .map(|f| f.result_field.to_owned().unwrap());
| |____________________________________________________^ help: try: `filter_map(|f| f.result_field.to_owned().ok())`
-error: aborting due to 12 previous errors
+error: aborting due to 27 previous errors
diff --git a/tests/ui/manual_find_map.fixed b/tests/ui/manual_find_map.fixed
index d69b6c1dcf3..54302beceff 100644
--- a/tests/ui/manual_find_map.fixed
+++ b/tests/ui/manual_find_map.fixed
@@ -12,6 +12,35 @@ fn main() {
// is_ok(), unwrap_or()
let _ = (0..).find_map(|a| to_res(a).ok());
+
+ let _ = (1..5)
+ .find_map(|y| *to_ref(to_opt(y)));
+ let _ = (1..5)
+ .find_map(|y| *to_ref(to_opt(y)));
+
+ let _ = (1..5)
+ .find_map(|y| to_ref(to_res(y)).ok());
+ let _ = (1..5)
+ .find_map(|y| to_ref(to_res(y)).ok());
+}
+
+#[rustfmt::skip]
+fn simple_equal() {
+ iter::<Option<u8>>().find_map(|x| x);
+ iter::<&Option<u8>>().find_map(|x| *x);
+ iter::<&&Option<u8>>().find_map(|x| **x);
+ iter::<Option<&u8>>().find_map(|x| x.cloned());
+ iter::<&Option<&u8>>().find_map(|x| x.cloned());
+ iter::<&Option<String>>().find_map(|x| x.as_deref());
+ iter::<Option<&String>>().find_map(|y| to_ref(y).cloned());
+
+ iter::<Result<u8, ()>>().find_map(|x| x.ok());
+ iter::<&Result<u8, ()>>().find_map(|x| x.ok());
+ iter::<&&Result<u8, ()>>().find_map(|x| x.ok());
+ iter::<Result<&u8, ()>>().find_map(|x| x.cloned().ok());
+ iter::<&Result<&u8, ()>>().find_map(|x| x.cloned().ok());
+ iter::<&Result<String, ()>>().find_map(|x| x.as_deref().ok());
+ iter::<Result<&String, ()>>().find_map(|y| to_ref(y).cloned().ok());
}
fn no_lint() {
@@ -28,6 +57,10 @@ fn no_lint() {
.map(|a| to_opt(a).unwrap());
}
+fn iter<T>() -> impl Iterator<Item = T> {
+ std::iter::empty()
+}
+
fn to_opt<T>(_: T) -> Option<T> {
unimplemented!()
}
@@ -36,6 +69,10 @@ fn to_res<T>(_: T) -> Result<T, ()> {
unimplemented!()
}
+fn to_ref<'a, T>(_: T) -> &'a T {
+ unimplemented!()
+}
+
struct Issue8920<'a> {
option_field: Option<String>,
result_field: Result<String, ()>,
diff --git a/tests/ui/manual_find_map.rs b/tests/ui/manual_find_map.rs
index 1c4e18e31c8..afcc1825a9a 100644
--- a/tests/ui/manual_find_map.rs
+++ b/tests/ui/manual_find_map.rs
@@ -12,6 +12,39 @@ fn main() {
// is_ok(), unwrap_or()
let _ = (0..).find(|&n| to_res(n).is_ok()).map(|a| to_res(a).unwrap_or(1));
+
+ let _ = (1..5)
+ .find(|&x| to_ref(to_opt(x)).is_some())
+ .map(|y| to_ref(to_opt(y)).unwrap());
+ let _ = (1..5)
+ .find(|x| to_ref(to_opt(*x)).is_some())
+ .map(|y| to_ref(to_opt(y)).unwrap());
+
+ let _ = (1..5)
+ .find(|&x| to_ref(to_res(x)).is_ok())
+ .map(|y| to_ref(to_res(y)).unwrap());
+ let _ = (1..5)
+ .find(|x| to_ref(to_res(*x)).is_ok())
+ .map(|y| to_ref(to_res(y)).unwrap());
+}
+
+#[rustfmt::skip]
+fn simple_equal() {
+ iter::<Option<u8>>().find(|x| x.is_some()).map(|x| x.unwrap());
+ iter::<&Option<u8>>().find(|x| x.is_some()).map(|x| x.unwrap());
+ iter::<&&Option<u8>>().find(|x| x.is_some()).map(|x| x.unwrap());
+ iter::<Option<&u8>>().find(|x| x.is_some()).map(|x| x.cloned().unwrap());
+ iter::<&Option<&u8>>().find(|x| x.is_some()).map(|x| x.cloned().unwrap());
+ iter::<&Option<String>>().find(|x| x.is_some()).map(|x| x.as_deref().unwrap());
+ iter::<Option<&String>>().find(|&x| to_ref(x).is_some()).map(|y| to_ref(y).cloned().unwrap());
+
+ iter::<Result<u8, ()>>().find(|x| x.is_ok()).map(|x| x.unwrap());
+ iter::<&Result<u8, ()>>().find(|x| x.is_ok()).map(|x| x.unwrap());
+ iter::<&&Result<u8, ()>>().find(|x| x.is_ok()).map(|x| x.unwrap());
+ iter::<Result<&u8, ()>>().find(|x| x.is_ok()).map(|x| x.cloned().unwrap());
+ iter::<&Result<&u8, ()>>().find(|x| x.is_ok()).map(|x| x.cloned().unwrap());
+ iter::<&Result<String, ()>>().find(|x| x.is_ok()).map(|x| x.as_deref().unwrap());
+ iter::<Result<&String, ()>>().find(|&x| to_ref(x).is_ok()).map(|y| to_ref(y).cloned().unwrap());
}
fn no_lint() {
@@ -28,6 +61,10 @@ fn no_lint() {
.map(|a| to_opt(a).unwrap());
}
+fn iter<T>() -> impl Iterator<Item = T> {
+ std::iter::empty()
+}
+
fn to_opt<T>(_: T) -> Option<T> {
unimplemented!()
}
@@ -36,6 +73,10 @@ fn to_res<T>(_: T) -> Result<T, ()> {
unimplemented!()
}
+fn to_ref<'a, T>(_: T) -> &'a T {
+ unimplemented!()
+}
+
struct Issue8920<'a> {
option_field: Option<String>,
result_field: Result<String, ()>,
diff --git a/tests/ui/manual_find_map.stderr b/tests/ui/manual_find_map.stderr
index 9dea42b7686..c1ac499f7c6 100644
--- a/tests/ui/manual_find_map.stderr
+++ b/tests/ui/manual_find_map.stderr
@@ -19,7 +19,123 @@ LL | let _ = (0..).find(|&n| to_res(n).is_ok()).map(|a| to_res(a).unwrap_or(
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `find_map(|a| to_res(a).ok())`
error: `find(..).map(..)` can be simplified as `find_map(..)`
- --> $DIR/manual_find_map.rs:54:10
+ --> $DIR/manual_find_map.rs:17:10
+ |
+LL | .find(|&x| to_ref(to_opt(x)).is_some())
+ | __________^
+LL | | .map(|y| to_ref(to_opt(y)).unwrap());
+ | |____________________________________________^ help: try: `find_map(|y| *to_ref(to_opt(y)))`
+
+error: `find(..).map(..)` can be simplified as `find_map(..)`
+ --> $DIR/manual_find_map.rs:20:10
+ |
+LL | .find(|x| to_ref(to_opt(*x)).is_some())
+ | __________^
+LL | | .map(|y| to_ref(to_opt(y)).unwrap());
+ | |____________________________________________^ help: try: `find_map(|y| *to_ref(to_opt(y)))`
+
+error: `find(..).map(..)` can be simplified as `find_map(..)`
+ --> $DIR/manual_find_map.rs:24:10
+ |
+LL | .find(|&x| to_ref(to_res(x)).is_ok())
+ | __________^
+LL | | .map(|y| to_ref(to_res(y)).unwrap());
+ | |____________________________________________^ help: try: `find_map(|y| to_ref(to_res(y)).ok())`
+
+error: `find(..).map(..)` can be simplified as `find_map(..)`
+ --> $DIR/manual_find_map.rs:27:10
+ |
+LL | .find(|x| to_ref(to_res(*x)).is_ok())
+ | __________^
+LL | | .map(|y| to_ref(to_res(y)).unwrap());
+ | |____________________________________________^ help: try: `find_map(|y| to_ref(to_res(y)).ok())`
+
+error: `find(..).map(..)` can be simplified as `find_map(..)`
+ --> $DIR/manual_find_map.rs:33:26
+ |
+LL | iter::<Option<u8>>().find(|x| x.is_some()).map(|x| x.unwrap());
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `find_map(|x| x)`
+
+error: `find(..).map(..)` can be simplified as `find_map(..)`
+ --> $DIR/manual_find_map.rs:34:27
+ |
+LL | iter::<&Option<u8>>().find(|x| x.is_some()).map(|x| x.unwrap());
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `find_map(|x| *x)`
+
+error: `find(..).map(..)` can be simplified as `find_map(..)`
+ --> $DIR/manual_find_map.rs:35:28
+ |
+LL | iter::<&&Option<u8>>().find(|x| x.is_some()).map(|x| x.unwrap());
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `find_map(|x| **x)`
+
+error: `find(..).map(..)` can be simplified as `find_map(..)`
+ --> $DIR/manual_find_map.rs:36:27
+ |
+LL | iter::<Option<&u8>>().find(|x| x.is_some()).map(|x| x.cloned().unwrap());
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `find_map(|x| x.cloned())`
+
+error: `find(..).map(..)` can be simplified as `find_map(..)`
+ --> $DIR/manual_find_map.rs:37:28
+ |
+LL | iter::<&Option<&u8>>().find(|x| x.is_some()).map(|x| x.cloned().unwrap());
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `find_map(|x| x.cloned())`
+
+error: `find(..).map(..)` can be simplified as `find_map(..)`
+ --> $DIR/manual_find_map.rs:38:31
+ |
+LL | iter::<&Option<String>>().find(|x| x.is_some()).map(|x| x.as_deref().unwrap());
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `find_map(|x| x.as_deref())`
+
+error: `find(..).map(..)` can be simplified as `find_map(..)`
+ --> $DIR/manual_find_map.rs:39:31
+ |
+LL | iter::<Option<&String>>().find(|&x| to_ref(x).is_some()).map(|y| to_ref(y).cloned().unwrap());
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `find_map(|y| to_ref(y).cloned())`
+
+error: `find(..).map(..)` can be simplified as `find_map(..)`
+ --> $DIR/manual_find_map.rs:41:30
+ |
+LL | iter::<Result<u8, ()>>().find(|x| x.is_ok()).map(|x| x.unwrap());
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `find_map(|x| x.ok())`
+
+error: `find(..).map(..)` can be simplified as `find_map(..)`
+ --> $DIR/manual_find_map.rs:42:31
+ |
+LL | iter::<&Result<u8, ()>>().find(|x| x.is_ok()).map(|x| x.unwrap());
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `find_map(|x| x.ok())`
+
+error: `find(..).map(..)` can be simplified as `find_map(..)`
+ --> $DIR/manual_find_map.rs:43:32
+ |
+LL | iter::<&&Result<u8, ()>>().find(|x| x.is_ok()).map(|x| x.unwrap());
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `find_map(|x| x.ok())`
+
+error: `find(..).map(..)` can be simplified as `find_map(..)`
+ --> $DIR/manual_find_map.rs:44:31
+ |
+LL | iter::<Result<&u8, ()>>().find(|x| x.is_ok()).map(|x| x.cloned().unwrap());
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `find_map(|x| x.cloned().ok())`
+
+error: `find(..).map(..)` can be simplified as `find_map(..)`
+ --> $DIR/manual_find_map.rs:45:32
+ |
+LL | iter::<&Result<&u8, ()>>().find(|x| x.is_ok()).map(|x| x.cloned().unwrap());
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `find_map(|x| x.cloned().ok())`
+
+error: `find(..).map(..)` can be simplified as `find_map(..)`
+ --> $DIR/manual_find_map.rs:46:35
+ |
+LL | iter::<&Result<String, ()>>().find(|x| x.is_ok()).map(|x| x.as_deref().unwrap());
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `find_map(|x| x.as_deref().ok())`
+
+error: `find(..).map(..)` can be simplified as `find_map(..)`
+ --> $DIR/manual_find_map.rs:47:35
+ |
+LL | iter::<Result<&String, ()>>().find(|&x| to_ref(x).is_ok()).map(|y| to_ref(y).cloned().unwrap());
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `find_map(|y| to_ref(y).cloned().ok())`
+
+error: `find(..).map(..)` can be simplified as `find_map(..)`
+ --> $DIR/manual_find_map.rs:95:10
|
LL | .find(|f| f.option_field.is_some())
| __________^
@@ -27,7 +143,7 @@ LL | | .map(|f| f.option_field.clone().unwrap());
| |_________________________________________________^ help: try: `find_map(|f| f.option_field.clone())`
error: `find(..).map(..)` can be simplified as `find_map(..)`
- --> $DIR/manual_find_map.rs:59:10
+ --> $DIR/manual_find_map.rs:100:10
|
LL | .find(|f| f.ref_field.is_some())
| __________^
@@ -35,7 +151,7 @@ LL | | .map(|f| f.ref_field.cloned().unwrap());
| |_______________________________________________^ help: try: `find_map(|f| f.ref_field.cloned())`
error: `find(..).map(..)` can be simplified as `find_map(..)`
- --> $DIR/manual_find_map.rs:64:10
+ --> $DIR/manual_find_map.rs:105:10
|
LL | .find(|f| f.ref_field.is_some())
| __________^
@@ -43,7 +159,7 @@ LL | | .map(|f| f.ref_field.copied().unwrap());
| |_______________________________________________^ help: try: `find_map(|f| f.ref_field.copied())`
error: `find(..).map(..)` can be simplified as `find_map(..)`
- --> $DIR/manual_find_map.rs:69:10
+ --> $DIR/manual_find_map.rs:110:10
|
LL | .find(|f| f.result_field.is_ok())
| __________^
@@ -51,7 +167,7 @@ LL | | .map(|f| f.result_field.clone().unwrap());
| |_________________________________________________^ help: try: `find_map(|f| f.result_field.clone().ok())`
error: `find(..).map(..)` can be simplified as `find_map(..)`
- --> $DIR/manual_find_map.rs:74:10
+ --> $DIR/manual_find_map.rs:115:10
|
LL | .find(|f| f.result_field.is_ok())
| __________^
@@ -59,7 +175,7 @@ LL | | .map(|f| f.result_field.as_ref().unwrap());
| |__________________________________________________^ help: try: `find_map(|f| f.result_field.as_ref().ok())`
error: `find(..).map(..)` can be simplified as `find_map(..)`
- --> $DIR/manual_find_map.rs:79:10
+ --> $DIR/manual_find_map.rs:120:10
|
LL | .find(|f| f.result_field.is_ok())
| __________^
@@ -67,7 +183,7 @@ LL | | .map(|f| f.result_field.as_deref().unwrap());
| |____________________________________________________^ help: try: `find_map(|f| f.result_field.as_deref().ok())`
error: `find(..).map(..)` can be simplified as `find_map(..)`
- --> $DIR/manual_find_map.rs:84:10
+ --> $DIR/manual_find_map.rs:125:10
|
LL | .find(|f| f.result_field.is_ok())
| __________^
@@ -75,7 +191,7 @@ LL | | .map(|f| f.result_field.as_mut().unwrap());
| |__________________________________________________^ help: try: `find_map(|f| f.result_field.as_mut().ok())`
error: `find(..).map(..)` can be simplified as `find_map(..)`
- --> $DIR/manual_find_map.rs:89:10
+ --> $DIR/manual_find_map.rs:130:10
|
LL | .find(|f| f.result_field.is_ok())
| __________^
@@ -83,12 +199,12 @@ LL | | .map(|f| f.result_field.as_deref_mut().unwrap());
| |________________________________________________________^ help: try: `find_map(|f| f.result_field.as_deref_mut().ok())`
error: `find(..).map(..)` can be simplified as `find_map(..)`
- --> $DIR/manual_find_map.rs:94:10
+ --> $DIR/manual_find_map.rs:135:10
|
LL | .find(|f| f.result_field.is_ok())
| __________^
LL | | .map(|f| f.result_field.to_owned().unwrap());
| |____________________________________________________^ help: try: `find_map(|f| f.result_field.to_owned().ok())`
-error: aborting due to 12 previous errors
+error: aborting due to 30 previous errors