[`manual_ok_or`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_ok_or
[`manual_range_contains`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_range_contains
[`manual_saturating_arithmetic`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_saturating_arithmetic
+[`manual_split_once`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_split_once
[`manual_str_repeat`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_str_repeat
[`manual_strip`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_strip
[`manual_swap`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_swap
methods::MANUAL_FILTER_MAP,
methods::MANUAL_FIND_MAP,
methods::MANUAL_SATURATING_ARITHMETIC,
+ methods::MANUAL_SPLIT_ONCE,
methods::MANUAL_STR_REPEAT,
methods::MAP_COLLECT_RESULT_UNIT,
methods::MAP_FLATTEN,
LintId::of(methods::MANUAL_FILTER_MAP),
LintId::of(methods::MANUAL_FIND_MAP),
LintId::of(methods::MANUAL_SATURATING_ARITHMETIC),
+ LintId::of(methods::MANUAL_SPLIT_ONCE),
LintId::of(methods::MANUAL_STR_REPEAT),
LintId::of(methods::MAP_COLLECT_RESULT_UNIT),
LintId::of(methods::MAP_IDENTITY),
LintId::of(methods::ITER_COUNT),
LintId::of(methods::MANUAL_FILTER_MAP),
LintId::of(methods::MANUAL_FIND_MAP),
+ LintId::of(methods::MANUAL_SPLIT_ONCE),
LintId::of(methods::MAP_IDENTITY),
LintId::of(methods::OPTION_AS_REF_DEREF),
LintId::of(methods::OPTION_FILTER_MAP),
--- /dev/null
+use clippy_utils::consts::{constant, Constant};
+use clippy_utils::diagnostics::span_lint_and_sugg;
+use clippy_utils::source::snippet_with_context;
+use clippy_utils::{is_diag_item_method, match_def_path, paths};
+use if_chain::if_chain;
+use rustc_errors::Applicability;
+use rustc_hir::{Expr, ExprKind, HirId, LangItem, Node, QPath};
+use rustc_lint::LateContext;
+use rustc_middle::ty::{self, adjustment::Adjust};
+use rustc_span::{symbol::sym, Span, SyntaxContext};
+
+use super::MANUAL_SPLIT_ONCE;
+
+pub(super) fn check(cx: &LateContext<'_>, method_name: &str, expr: &Expr<'_>, self_arg: &Expr<'_>, pat_arg: &Expr<'_>) {
+ if !cx.typeck_results().expr_ty_adjusted(self_arg).peel_refs().is_str() {
+ return;
+ }
+
+ let ctxt = expr.span.ctxt();
+ let usage = match parse_iter_usage(cx, ctxt, cx.tcx.hir().parent_iter(expr.hir_id)) {
+ Some(x) => x,
+ None => return,
+ };
+ let (method_name, msg) = if method_name == "splitn" {
+ ("split_once", "manual implementation of `split_once`")
+ } else {
+ ("rsplit_once", "manual implementation of `rsplit_once`")
+ };
+
+ let mut app = Applicability::MachineApplicable;
+ let self_snip = snippet_with_context(cx, self_arg.span, ctxt, "..", &mut app).0;
+ let pat_snip = snippet_with_context(cx, pat_arg.span, ctxt, "..", &mut app).0;
+
+ match usage.kind {
+ IterUsageKind::NextTuple => {
+ span_lint_and_sugg(
+ cx,
+ MANUAL_SPLIT_ONCE,
+ usage.span,
+ msg,
+ "try this",
+ format!("{}.{}({})", self_snip, method_name, pat_snip),
+ app,
+ );
+ },
+ IterUsageKind::Next => {
+ let self_deref = {
+ let adjust = cx.typeck_results().expr_adjustments(self_arg);
+ if adjust.is_empty() {
+ String::new()
+ } else if cx.typeck_results().expr_ty(self_arg).is_box()
+ || adjust
+ .iter()
+ .any(|a| matches!(a.kind, Adjust::Deref(Some(_))) || a.target.is_box())
+ {
+ format!("&{}", "*".repeat(adjust.len() - 1))
+ } else {
+ "*".repeat(adjust.len() - 2)
+ }
+ };
+ let sugg = if usage.unwrap_kind.is_some() {
+ format!(
+ "{}.{}({}).map_or({}{}, |x| x.0)",
+ &self_snip, method_name, pat_snip, self_deref, &self_snip
+ )
+ } else {
+ format!(
+ "Some({}.{}({}).map_or({}{}, |x| x.0))",
+ &self_snip, method_name, pat_snip, self_deref, &self_snip
+ )
+ };
+
+ span_lint_and_sugg(cx, MANUAL_SPLIT_ONCE, usage.span, msg, "try this", sugg, app);
+ },
+ IterUsageKind::Second => {
+ let access_str = match usage.unwrap_kind {
+ Some(UnwrapKind::Unwrap) => ".unwrap().1",
+ Some(UnwrapKind::QuestionMark) => "?.1",
+ None => ".map(|x| x.1)",
+ };
+ span_lint_and_sugg(
+ cx,
+ MANUAL_SPLIT_ONCE,
+ usage.span,
+ msg,
+ "try this",
+ format!("{}.{}({}){}", self_snip, method_name, pat_snip, access_str),
+ app,
+ );
+ },
+ }
+}
+
+enum IterUsageKind {
+ Next,
+ Second,
+ NextTuple,
+}
+
+enum UnwrapKind {
+ Unwrap,
+ QuestionMark,
+}
+
+struct IterUsage {
+ kind: IterUsageKind,
+ unwrap_kind: Option<UnwrapKind>,
+ span: Span,
+}
+
+fn parse_iter_usage(
+ cx: &LateContext<'tcx>,
+ ctxt: SyntaxContext,
+ mut iter: impl Iterator<Item = (HirId, Node<'tcx>)>,
+) -> Option<IterUsage> {
+ let (kind, span) = match iter.next() {
+ Some((_, Node::Expr(e))) if e.span.ctxt() == ctxt => {
+ let (name, args) = if let ExprKind::MethodCall(name, _, [_, args @ ..], _) = e.kind {
+ (name, args)
+ } else {
+ return None;
+ };
+ let did = cx.typeck_results().type_dependent_def_id(e.hir_id)?;
+ let iter_id = cx.tcx.get_diagnostic_item(sym::Iterator)?;
+
+ match (&*name.ident.as_str(), args) {
+ ("next", []) if cx.tcx.trait_of_item(did) == Some(iter_id) => (IterUsageKind::Next, e.span),
+ ("next_tuple", []) => {
+ if_chain! {
+ if match_def_path(cx, did, &paths::ITERTOOLS_NEXT_TUPLE);
+ if let ty::Adt(adt_def, subs) = cx.typeck_results().expr_ty(e).kind();
+ if cx.tcx.is_diagnostic_item(sym::option_type, adt_def.did);
+ if let ty::Tuple(subs) = subs.type_at(0).kind();
+ if subs.len() == 2;
+ then {
+ return Some(IterUsage { kind: IterUsageKind::NextTuple, span: e.span, unwrap_kind: None });
+ } else {
+ return None;
+ }
+ }
+ },
+ ("nth" | "skip", [idx_expr]) if cx.tcx.trait_of_item(did) == Some(iter_id) => {
+ if let Some((Constant::Int(idx), _)) = constant(cx, cx.typeck_results(), idx_expr) {
+ let span = if name.ident.as_str() == "nth" {
+ e.span
+ } else {
+ if_chain! {
+ if let Some((_, Node::Expr(next_expr))) = iter.next();
+ if let ExprKind::MethodCall(next_name, _, [_], _) = next_expr.kind;
+ if next_name.ident.name == sym::next;
+ if next_expr.span.ctxt() == ctxt;
+ if let Some(next_id) = cx.typeck_results().type_dependent_def_id(next_expr.hir_id);
+ if cx.tcx.trait_of_item(next_id) == Some(iter_id);
+ then {
+ next_expr.span
+ } else {
+ return None;
+ }
+ }
+ };
+ match idx {
+ 0 => (IterUsageKind::Next, span),
+ 1 => (IterUsageKind::Second, span),
+ _ => return None,
+ }
+ } else {
+ return None;
+ }
+ },
+ _ => return None,
+ }
+ },
+ _ => return None,
+ };
+
+ let (unwrap_kind, span) = if let Some((_, Node::Expr(e))) = iter.next() {
+ match e.kind {
+ ExprKind::Call(
+ Expr {
+ kind: ExprKind::Path(QPath::LangItem(LangItem::TryTraitBranch, _)),
+ ..
+ },
+ _,
+ ) => {
+ let parent_span = e.span.parent().unwrap();
+ if parent_span.ctxt() == ctxt {
+ (Some(UnwrapKind::QuestionMark), parent_span)
+ } else {
+ (None, span)
+ }
+ },
+ _ if e.span.ctxt() != ctxt => (None, span),
+ ExprKind::MethodCall(name, _, [_], _)
+ if name.ident.name == sym::unwrap
+ && cx
+ .typeck_results()
+ .type_dependent_def_id(e.hir_id)
+ .map_or(false, |id| is_diag_item_method(cx, id, sym::option_type)) =>
+ {
+ (Some(UnwrapKind::Unwrap), e.span)
+ },
+ _ => (None, span),
+ }
+ } else {
+ (None, span)
+ };
+
+ Some(IterUsage {
+ kind,
+ unwrap_kind,
+ span,
+ })
+}
mod iter_skip_next;
mod iterator_step_by_zero;
mod manual_saturating_arithmetic;
+mod manual_split_once;
mod manual_str_repeat;
mod map_collect_result_unit;
mod map_flatten;
mod zst_offset;
use bind_instead_of_map::BindInsteadOfMap;
+use clippy_utils::consts::{constant, Constant};
use clippy_utils::diagnostics::{span_lint, span_lint_and_help};
use clippy_utils::ty::{contains_adt_constructor, contains_ty, implements_trait, is_copy, is_type_diagnostic_item};
use clippy_utils::{contains_return, get_trait_def_id, in_macro, iter_input_pats, meets_msrv, msrvs, paths, return_ty};
"manual implementation of `str::repeat`"
}
+declare_clippy_lint! {
+ /// **What it does:** Checks for usages of `splitn(2, _)`
+ ///
+ /// **Why is this bad?** `split_once` is clearer.
+ ///
+ /// **Known problems:** None.
+ ///
+ /// **Example:**
+ ///
+ /// ```rust
+ /// // Bad
+ /// let some_str = "name=value";
+ /// let mut iter = some_str.splitn(2, '=');
+ /// let name = iter.next().unwrap();
+ /// let value = iter.next().unwrap_or("");
+ ///
+ /// // Good
+ /// let some_str = "name=value";
+ /// let (name, value) = some_str.split_once('=').unwrap_or((some_str, ""));
+ /// ```
+ pub MANUAL_SPLIT_ONCE,
+ complexity,
+ "replace `.splitn(2, pat)` with `.split_once(pat)`"
+}
+
pub struct Methods {
avoid_breaking_exported_api: bool,
msrv: Option<RustcVersion>,
IMPLICIT_CLONE,
SUSPICIOUS_SPLITN,
MANUAL_STR_REPEAT,
- EXTEND_WITH_DRAIN
+ EXTEND_WITH_DRAIN,
+ MANUAL_SPLIT_ONCE
]);
/// Extracts a method call name, args, and `Span` of the method name.
unnecessary_lazy_eval::check(cx, expr, recv, arg, "or");
}
},
- ("splitn" | "splitn_mut" | "rsplitn" | "rsplitn_mut", [count_arg, _]) => {
- suspicious_splitn::check(cx, name, expr, recv, count_arg);
+ ("splitn" | "rsplitn", [count_arg, pat_arg]) => {
+ if let Some((Constant::Int(count), _)) = constant(cx, cx.typeck_results(), count_arg) {
+ suspicious_splitn::check(cx, name, expr, recv, count);
+ if count == 2 && meets_msrv(msrv, &msrvs::STR_SPLIT_ONCE) {
+ manual_split_once::check(cx, name, expr, recv, pat_arg);
+ }
+ }
+ },
+ ("splitn_mut" | "rsplitn_mut", [count_arg, _]) => {
+ if let Some((Constant::Int(count), _)) = constant(cx, cx.typeck_results(), count_arg) {
+ suspicious_splitn::check(cx, name, expr, recv, count);
+ }
},
("step_by", [arg]) => iterator_step_by_zero::check(cx, expr, arg),
("to_os_string" | "to_owned" | "to_path_buf" | "to_vec", []) => {
-use clippy_utils::consts::{constant, Constant};
use clippy_utils::diagnostics::span_lint_and_note;
use if_chain::if_chain;
use rustc_ast::LitKind;
use super::SUSPICIOUS_SPLITN;
-pub(super) fn check(
- cx: &LateContext<'_>,
- method_name: &str,
- expr: &Expr<'_>,
- self_arg: &Expr<'_>,
- count_arg: &Expr<'_>,
-) {
+pub(super) fn check(cx: &LateContext<'_>, method_name: &str, expr: &Expr<'_>, self_arg: &Expr<'_>, count: u128) {
if_chain! {
- if let Some((Constant::Int(count), _)) = constant(cx, cx.typeck_results(), count_arg);
if count <= 1;
if let Some(call_id) = cx.typeck_results().type_dependent_def_id(expr.hir_id);
if let Some(impl_id) = cx.tcx.impl_of_method(call_id);
if lang_items.slice_impl() == Some(impl_id) || lang_items.str_impl() == Some(impl_id);
then {
// Ignore empty slice and string literals when used with a literal count.
- if (matches!(self_arg.kind, ExprKind::Array([]))
+ if matches!(self_arg.kind, ExprKind::Array([]))
|| matches!(self_arg.kind, ExprKind::Lit(Spanned { node: LitKind::Str(s, _), .. }) if s.is_empty())
- ) && matches!(count_arg.kind, ExprKind::Lit(_))
+
{
return;
}
///
/// Suppress lints whenever the suggested change would cause breakage for other crates.
(avoid_breaking_exported_api: bool = true),
- /// Lint: MANUAL_STR_REPEAT, CLONED_INSTEAD_OF_COPIED, REDUNDANT_FIELD_NAMES, REDUNDANT_STATIC_LIFETIMES, FILTER_MAP_NEXT, CHECKED_CONVERSIONS, MANUAL_RANGE_CONTAINS, USE_SELF, MEM_REPLACE_WITH_DEFAULT, MANUAL_NON_EXHAUSTIVE, OPTION_AS_REF_DEREF, MAP_UNWRAP_OR, MATCH_LIKE_MATCHES_MACRO, MANUAL_STRIP, MISSING_CONST_FOR_FN, UNNESTED_OR_PATTERNS, FROM_OVER_INTO, PTR_AS_PTR, IF_THEN_SOME_ELSE_NONE.
+ /// Lint: MANUAL_SPLIT_ONCE, MANUAL_STR_REPEAT, CLONED_INSTEAD_OF_COPIED, REDUNDANT_FIELD_NAMES, REDUNDANT_STATIC_LIFETIMES, FILTER_MAP_NEXT, CHECKED_CONVERSIONS, MANUAL_RANGE_CONTAINS, USE_SELF, MEM_REPLACE_WITH_DEFAULT, MANUAL_NON_EXHAUSTIVE, OPTION_AS_REF_DEREF, MAP_UNWRAP_OR, MATCH_LIKE_MATCHES_MACRO, MANUAL_STRIP, MISSING_CONST_FOR_FN, UNNESTED_OR_PATTERNS, FROM_OVER_INTO, PTR_AS_PTR, IF_THEN_SOME_ELSE_NONE.
///
/// The minimum rust version that the project supports
(msrv: Option<String> = None),
"for further information visit https://rust-lang.github.io/rust-clippy/{}/index.html#{}",
&option_env!("RUST_RELEASE_NUM").map_or("master".to_string(), |n| {
// extract just major + minor version and ignore patch versions
- format!("rust-{}", n.rsplitn(2, '.').nth(1).unwrap())
+ format!("rust-{}", n.rsplit_once('.').unwrap().1)
}),
lint
));
// names may refer to stabilized feature flags or library items
msrv_aliases! {
1,53,0 { OR_PATTERNS }
+ 1,52,0 { STR_SPLIT_ONCE }
1,50,0 { BOOL_THEN }
1,46,0 { CONST_IF_MATCH }
1,45,0 { STR_STRIP_PREFIX }
pub const IPADDR_V4: [&str; 5] = ["std", "net", "ip", "IpAddr", "V4"];
pub const IPADDR_V6: [&str; 5] = ["std", "net", "ip", "IpAddr", "V6"];
pub const ITER_REPEAT: [&str; 5] = ["core", "iter", "sources", "repeat", "repeat"];
+pub const ITERTOOLS_NEXT_TUPLE: [&str; 3] = ["itertools", "Itertools", "next_tuple"];
#[cfg(feature = "internal-lints")]
pub const KW_MODULE: [&str; 3] = ["rustc_span", "symbol", "kw"];
#[cfg(feature = "internal-lints")]
}
}
};
- ([$t:ident], $f:ident) => {
- impl Visitable<'tcx> for &'tcx [$t<'tcx>] {
- fn visit<V: Visitor<'tcx>>(self, visitor: &mut V) {
- for x in self {
- visitor.$f(x);
- }
- }
- }
- };
}
visitable_ref!(Arm, visit_arm);
visitable_ref!(Block, visit_block);
visitable_ref!(Body, visit_body);
visitable_ref!(Expr, visit_expr);
visitable_ref!(Stmt, visit_stmt);
-visitable_ref!([Stmt], visit_stmt);
+
+// impl<'tcx, I: IntoIterator> Visitable<'tcx> for I
+// where
+// I::Item: Visitable<'tcx>,
+// {
+// fn visit<V: Visitor<'tcx>>(self, visitor: &mut V) {
+// for x in self {
+// x.visit(visitor);
+// }
+// }
+// }
/// Calls the given function for each break expression.
pub fn visit_break_exprs<'tcx>(
"clippy_lints",
"clippy_utils",
"if_chain",
+ "itertools",
"quote",
"regex",
"serde",
--- /dev/null
+// run-rustfix
+
+#![feature(custom_inner_attributes)]
+#![warn(clippy::manual_split_once)]
+#![allow(clippy::iter_skip_next, clippy::iter_nth_zero)]
+
+extern crate itertools;
+
+#[allow(unused_imports)]
+use itertools::Itertools;
+
+fn main() {
+ let _ = Some("key=value".split_once('=').map_or("key=value", |x| x.0));
+ let _ = "key=value".splitn(2, '=').nth(2);
+ let _ = "key=value".split_once('=').map_or("key=value", |x| x.0);
+ let _ = "key=value".split_once('=').map_or("key=value", |x| x.0);
+ let _ = "key=value".split_once('=').unwrap().1;
+ let _ = "key=value".split_once('=').unwrap().1;
+ let (_, _) = "key=value".split_once('=').unwrap();
+
+ let s = String::from("key=value");
+ let _ = s.split_once('=').map_or(&*s, |x| x.0);
+
+ let s = Box::<str>::from("key=value");
+ let _ = s.split_once('=').map_or(&*s, |x| x.0);
+
+ let s = &"key=value";
+ let _ = s.split_once('=').map_or(*s, |x| x.0);
+
+ fn _f(s: &str) -> Option<&str> {
+ let _ = s.split_once("key=value").map_or(s, |x| x.0);
+ let _ = s.split_once("key=value")?.1;
+ let _ = s.split_once("key=value")?.1;
+ None
+ }
+
+ // Don't lint, slices don't have `split_once`
+ let _ = [0, 1, 2].splitn(2, |&x| x == 1).nth(1).unwrap();
+}
+
+fn _msrv_1_51() {
+ #![clippy::msrv = "1.51"]
+ // `str::split_once` was stabilized in 1.16. Do not lint this
+ let _ = "key=value".splitn(2, '=').nth(1).unwrap();
+}
+
+fn _msrv_1_52() {
+ #![clippy::msrv = "1.52"]
+ let _ = "key=value".split_once('=').unwrap().1;
+}
--- /dev/null
+// run-rustfix
+
+#![feature(custom_inner_attributes)]
+#![warn(clippy::manual_split_once)]
+#![allow(clippy::iter_skip_next, clippy::iter_nth_zero)]
+
+extern crate itertools;
+
+#[allow(unused_imports)]
+use itertools::Itertools;
+
+fn main() {
+ let _ = "key=value".splitn(2, '=').next();
+ let _ = "key=value".splitn(2, '=').nth(2);
+ let _ = "key=value".splitn(2, '=').next().unwrap();
+ let _ = "key=value".splitn(2, '=').nth(0).unwrap();
+ let _ = "key=value".splitn(2, '=').nth(1).unwrap();
+ let _ = "key=value".splitn(2, '=').skip(1).next().unwrap();
+ let (_, _) = "key=value".splitn(2, '=').next_tuple().unwrap();
+
+ let s = String::from("key=value");
+ let _ = s.splitn(2, '=').next().unwrap();
+
+ let s = Box::<str>::from("key=value");
+ let _ = s.splitn(2, '=').nth(0).unwrap();
+
+ let s = &"key=value";
+ let _ = s.splitn(2, '=').skip(0).next().unwrap();
+
+ fn _f(s: &str) -> Option<&str> {
+ let _ = s.splitn(2, "key=value").next()?;
+ let _ = s.splitn(2, "key=value").nth(1)?;
+ let _ = s.splitn(2, "key=value").skip(1).next()?;
+ None
+ }
+
+ // Don't lint, slices don't have `split_once`
+ let _ = [0, 1, 2].splitn(2, |&x| x == 1).nth(1).unwrap();
+}
+
+fn _msrv_1_51() {
+ #![clippy::msrv = "1.51"]
+ // `str::split_once` was stabilized in 1.16. Do not lint this
+ let _ = "key=value".splitn(2, '=').nth(1).unwrap();
+}
+
+fn _msrv_1_52() {
+ #![clippy::msrv = "1.52"]
+ let _ = "key=value".splitn(2, '=').nth(1).unwrap();
+}
--- /dev/null
+error: manual implementation of `split_once`
+ --> $DIR/manual_split_once.rs:13:13
+ |
+LL | let _ = "key=value".splitn(2, '=').next();
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try this: `Some("key=value".split_once('=').map_or("key=value", |x| x.0))`
+ |
+ = note: `-D clippy::manual-split-once` implied by `-D warnings`
+
+error: manual implementation of `split_once`
+ --> $DIR/manual_split_once.rs:15:13
+ |
+LL | let _ = "key=value".splitn(2, '=').next().unwrap();
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try this: `"key=value".split_once('=').map_or("key=value", |x| x.0)`
+
+error: manual implementation of `split_once`
+ --> $DIR/manual_split_once.rs:16:13
+ |
+LL | let _ = "key=value".splitn(2, '=').nth(0).unwrap();
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try this: `"key=value".split_once('=').map_or("key=value", |x| x.0)`
+
+error: manual implementation of `split_once`
+ --> $DIR/manual_split_once.rs:17:13
+ |
+LL | let _ = "key=value".splitn(2, '=').nth(1).unwrap();
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try this: `"key=value".split_once('=').unwrap().1`
+
+error: manual implementation of `split_once`
+ --> $DIR/manual_split_once.rs:18:13
+ |
+LL | let _ = "key=value".splitn(2, '=').skip(1).next().unwrap();
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try this: `"key=value".split_once('=').unwrap().1`
+
+error: manual implementation of `split_once`
+ --> $DIR/manual_split_once.rs:19:18
+ |
+LL | let (_, _) = "key=value".splitn(2, '=').next_tuple().unwrap();
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try this: `"key=value".split_once('=')`
+
+error: manual implementation of `split_once`
+ --> $DIR/manual_split_once.rs:22:13
+ |
+LL | let _ = s.splitn(2, '=').next().unwrap();
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try this: `s.split_once('=').map_or(&*s, |x| x.0)`
+
+error: manual implementation of `split_once`
+ --> $DIR/manual_split_once.rs:25:13
+ |
+LL | let _ = s.splitn(2, '=').nth(0).unwrap();
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try this: `s.split_once('=').map_or(&*s, |x| x.0)`
+
+error: manual implementation of `split_once`
+ --> $DIR/manual_split_once.rs:28:13
+ |
+LL | let _ = s.splitn(2, '=').skip(0).next().unwrap();
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try this: `s.split_once('=').map_or(*s, |x| x.0)`
+
+error: manual implementation of `split_once`
+ --> $DIR/manual_split_once.rs:31:17
+ |
+LL | let _ = s.splitn(2, "key=value").next()?;
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try this: `s.split_once("key=value").map_or(s, |x| x.0)`
+
+error: manual implementation of `split_once`
+ --> $DIR/manual_split_once.rs:32:17
+ |
+LL | let _ = s.splitn(2, "key=value").nth(1)?;
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try this: `s.split_once("key=value")?.1`
+
+error: manual implementation of `split_once`
+ --> $DIR/manual_split_once.rs:33:17
+ |
+LL | let _ = s.splitn(2, "key=value").skip(1).next()?;
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try this: `s.split_once("key=value")?.1`
+
+error: manual implementation of `split_once`
+ --> $DIR/manual_split_once.rs:49:13
+ |
+LL | let _ = "key=value".splitn(2, '=').nth(1).unwrap();
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try this: `"key=value".split_once('=').unwrap().1`
+
+error: aborting due to 13 previous errors
+
projects / rust.git / commitdiff