From f072ded3bf6286668ff8eade5b58e471dbe66f2a Mon Sep 17 00:00:00 2001 From: Eduardo Broto Date: Fri, 1 May 2020 01:44:17 +0200 Subject: [PATCH 1/3] Implement the manual_non_exhaustive lint --- CHANGELOG.md | 1 + clippy_lints/src/lib.rs | 5 + clippy_lints/src/manual_non_exhaustive.rs | 167 ++++++++++++++++++++++ src/lintlist/mod.rs | 7 + tests/ui/manual_non_exhaustive.rs | 124 ++++++++++++++++ tests/ui/manual_non_exhaustive.stderr | 48 +++++++ 6 files changed, 352 insertions(+) create mode 100644 clippy_lints/src/manual_non_exhaustive.rs create mode 100644 tests/ui/manual_non_exhaustive.rs create mode 100644 tests/ui/manual_non_exhaustive.stderr diff --git a/CHANGELOG.md b/CHANGELOG.md index 575773580c0b..facf363e371e 100644 --- a/CHANGELOG.md +++ b/CHANGELOG.md @@ -1423,6 +1423,7 @@ Released 2018-09-13 [`macro_use_imports`]: https://rust-lang.github.io/rust-clippy/master/index.html#macro_use_imports [`main_recursion`]: https://rust-lang.github.io/rust-clippy/master/index.html#main_recursion [`manual_memcpy`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_memcpy +[`manual_non_exhaustive`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_non_exhaustive [`manual_saturating_arithmetic`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_saturating_arithmetic [`manual_swap`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_swap [`many_single_char_names`]: https://rust-lang.github.io/rust-clippy/master/index.html#many_single_char_names diff --git a/clippy_lints/src/lib.rs b/clippy_lints/src/lib.rs index c995be5edc25..64f3a8a0ebbb 100644 --- a/clippy_lints/src/lib.rs +++ b/clippy_lints/src/lib.rs @@ -247,6 +247,7 @@ mod literal_representation; mod loops; mod macro_use; mod main_recursion; +mod manual_non_exhaustive; mod map_clone; mod map_unit_fn; mod match_on_vec_items; @@ -628,6 +629,7 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf: &loops::WHILE_LET_ON_ITERATOR, ¯o_use::MACRO_USE_IMPORTS, &main_recursion::MAIN_RECURSION, + &manual_non_exhaustive::MANUAL_NON_EXHAUSTIVE, &map_clone::MAP_CLONE, &map_unit_fn::OPTION_MAP_UNIT_FN, &map_unit_fn::RESULT_MAP_UNIT_FN, @@ -1064,6 +1066,7 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf: store.register_late_pass(|| box utils::internal_lints::CollapsibleCalls); store.register_late_pass(|| box if_let_mutex::IfLetMutex); store.register_late_pass(|| box match_on_vec_items::MatchOnVecItems); + store.register_early_pass(|| box manual_non_exhaustive::ManualNonExhaustive); store.register_group(true, "clippy::restriction", Some("clippy_restriction"), vec![ LintId::of(&arithmetic::FLOAT_ARITHMETIC), @@ -1280,6 +1283,7 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf: LintId::of(&loops::WHILE_LET_LOOP), LintId::of(&loops::WHILE_LET_ON_ITERATOR), LintId::of(&main_recursion::MAIN_RECURSION), + LintId::of(&manual_non_exhaustive::MANUAL_NON_EXHAUSTIVE), LintId::of(&map_clone::MAP_CLONE), LintId::of(&map_unit_fn::OPTION_MAP_UNIT_FN), LintId::of(&map_unit_fn::RESULT_MAP_UNIT_FN), @@ -1474,6 +1478,7 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf: LintId::of(&loops::NEEDLESS_RANGE_LOOP), LintId::of(&loops::WHILE_LET_ON_ITERATOR), LintId::of(&main_recursion::MAIN_RECURSION), + LintId::of(&manual_non_exhaustive::MANUAL_NON_EXHAUSTIVE), LintId::of(&map_clone::MAP_CLONE), LintId::of(&matches::INFALLIBLE_DESTRUCTURING_MATCH), LintId::of(&matches::MATCH_OVERLAPPING_ARM), diff --git a/clippy_lints/src/manual_non_exhaustive.rs b/clippy_lints/src/manual_non_exhaustive.rs new file mode 100644 index 000000000000..ca2a2cf2e1e7 --- /dev/null +++ b/clippy_lints/src/manual_non_exhaustive.rs @@ -0,0 +1,167 @@ +use crate::utils::{snippet_opt, span_lint_and_then}; +use if_chain::if_chain; +use rustc_ast::ast::{Attribute, Ident, Item, ItemKind, StructField, TyKind, Variant, VariantData, VisibilityKind}; +use rustc_attr as attr; +use rustc_errors::Applicability; +use rustc_lint::{EarlyContext, EarlyLintPass}; +use rustc_session::{declare_lint_pass, declare_tool_lint}; + +declare_clippy_lint! { + /// **What it does:** Checks for manual implementations of the non-exhaustive pattern. + /// + /// **Why is this bad?** Using the #[non_exhaustive] attribute expresses better the intent + /// and allows possible optimizations when applied to enums. + /// + /// **Known problems:** None. + /// + /// **Example:** + /// + /// ```rust + /// struct S { + /// pub a: i32, + /// pub b: i32, + /// _c: (), + /// } + /// + /// enum E { + /// A, + /// B, + /// #[doc(hidden)] + /// _C, + /// } + /// + /// struct T(pub i32, pub i32, ()); + /// ``` + /// Use instead: + /// ```rust + /// #[non_exhaustive] + /// struct S { + /// pub a: i32, + /// pub b: i32, + /// } + /// + /// #[non_exhaustive] + /// enum E { + /// A, + /// B, + /// } + /// + /// #[non_exhaustive] + /// struct T(pub i32, pub i32); + /// ``` + pub MANUAL_NON_EXHAUSTIVE, + style, + "manual implementations of the non-exhaustive pattern can be simplified using #[non_exhaustive]" +} + +declare_lint_pass!(ManualNonExhaustive => [MANUAL_NON_EXHAUSTIVE]); + +impl EarlyLintPass for ManualNonExhaustive { + fn check_item(&mut self, cx: &EarlyContext<'_>, item: &Item) { + match &item.kind { + ItemKind::Enum(def, _) => { + check_manual_non_exhaustive_enum(cx, item, &def.variants); + }, + ItemKind::Struct(variant_data, _) => { + if let VariantData::Unit(..) = variant_data { + return; + } + + check_manual_non_exhaustive_struct(cx, item, variant_data); + }, + _ => {}, + } + } +} + +fn check_manual_non_exhaustive_enum(cx: &EarlyContext<'_>, item: &Item, variants: &[Variant]) { + fn is_non_exhaustive_marker(variant: &Variant) -> bool { + matches!(variant.data, VariantData::Unit(_)) + && variant.ident.as_str().starts_with('_') + && variant.attrs.iter().any(|a| is_doc_hidden(a)) + } + + fn is_doc_hidden(attr: &Attribute) -> bool { + attr.check_name(sym!(doc)) + && match attr.meta_item_list() { + Some(l) => attr::list_contains_name(&l, sym!(hidden)), + None => false, + } + } + + if_chain! { + if !attr::contains_name(&item.attrs, sym!(non_exhaustive)); + let markers = variants.iter().filter(|v| is_non_exhaustive_marker(v)).count(); + if markers == 1 && variants.len() > markers; + if let Some(variant) = variants.last(); + if is_non_exhaustive_marker(variant); + then { + span_lint_and_then( + cx, + MANUAL_NON_EXHAUSTIVE, + item.span, + "this seems like a manual implementation of the non-exhaustive pattern", + |diag| { + let header_span = cx.sess.source_map().span_until_char(item.span, '{'); + + if let Some(snippet) = snippet_opt(cx, header_span) { + diag.span_suggestion( + item.span, + "add the attribute", + format!("#[non_exhaustive] {}", snippet), + Applicability::Unspecified, + ); + diag.span_help(variant.span, "and remove this variant"); + } + }); + } + } +} + +fn check_manual_non_exhaustive_struct(cx: &EarlyContext<'_>, item: &Item, data: &VariantData) { + fn is_private(field: &StructField) -> bool { + matches!(field.vis.node, VisibilityKind::Inherited) + } + + fn is_non_exhaustive_marker(name: &Option) -> bool { + name.map(|n| n.as_str().starts_with('_')).unwrap_or(true) + } + + let fields = data.fields(); + let private_fields = fields.iter().filter(|f| is_private(f)).count(); + let public_fields = fields.iter().filter(|f| f.vis.node.is_pub()).count(); + + if_chain! { + if !attr::contains_name(&item.attrs, sym!(non_exhaustive)); + if private_fields == 1 && public_fields >= private_fields && public_fields == fields.len() - 1; + if let Some(field) = fields.iter().find(|f| is_private(f)); + if is_non_exhaustive_marker(&field.ident); + if let TyKind::Tup(tup_fields) = &field.ty.kind; + if tup_fields.is_empty(); + then { + span_lint_and_then( + cx, + MANUAL_NON_EXHAUSTIVE, + item.span, + "this seems like a manual implementation of the non-exhaustive pattern", + |diag| { + let delimiter = match data { + VariantData::Struct(..) => '{', + VariantData::Tuple(..) => '(', + _ => unreachable!(), + }; + let header_span = cx.sess.source_map().span_until_char(item.span, delimiter); + + if let Some(snippet) = snippet_opt(cx, header_span) { + diag.span_suggestion( + item.span, + "add the attribute", + format!("#[non_exhaustive] {}", snippet), + Applicability::Unspecified, + ); + diag.span_help(field.span, "and remove this field"); + } + }); + } + } +} diff --git a/src/lintlist/mod.rs b/src/lintlist/mod.rs index 72675c25175c..c5360002fa05 100644 --- a/src/lintlist/mod.rs +++ b/src/lintlist/mod.rs @@ -1088,6 +1088,13 @@ pub static ref ALL_LINTS: Vec = vec![ deprecation: None, module: "loops", }, + Lint { + name: "manual_non_exhaustive", + group: "style", + desc: "manual implementations of the non-exhaustive pattern can be simplified using #[non_exhaustive]", + deprecation: None, + module: "manual_non_exhaustive", + }, Lint { name: "manual_saturating_arithmetic", group: "style", diff --git a/tests/ui/manual_non_exhaustive.rs b/tests/ui/manual_non_exhaustive.rs new file mode 100644 index 000000000000..9c239db6e00d --- /dev/null +++ b/tests/ui/manual_non_exhaustive.rs @@ -0,0 +1,124 @@ +#![warn(clippy::manual_non_exhaustive)] +#![allow(unused)] + +mod enums { + enum E { + A, + B, + #[doc(hidden)] + _C, + } + + // last variant does not have doc hidden attribute, should be ignored + enum NoDocHidden { + A, + B, + _C, + } + + // name of variant with doc hidden does not start with underscore, should be ignored + enum NoUnderscore { + A, + B, + #[doc(hidden)] + C, + } + + // variant with doc hidden is not unit, should be ignored + enum NotUnit { + A, + B, + #[doc(hidden)] + _C(bool), + } + + // variant with doc hidden is not the last one, should be ignored + enum NotLast { + A, + #[doc(hidden)] + _B, + C, + } + + // variant with doc hidden is the only one, should be ignored + enum OnlyMarker { + #[doc(hidden)] + _A, + } + + // variant with multiple non-exhaustive "markers", should be ignored + enum MultipleMarkers { + A, + #[doc(hidden)] + _B, + #[doc(hidden)] + _C, + } + + // already non_exhaustive, should be ignored + #[non_exhaustive] + enum NonExhaustive { + A, + B, + } +} + +mod structs { + struct S { + pub a: i32, + pub b: i32, + _c: (), + } + + // some other fields are private, should be ignored + struct PrivateFields { + a: i32, + pub b: i32, + _c: (), + } + + // private field name does not start with underscore, should be ignored + struct NoUnderscore { + pub a: i32, + pub b: i32, + c: (), + } + + // private field is not unit type, should be ignored + struct NotUnit { + pub a: i32, + pub b: i32, + _c: i32, + } + + // private field is the only field, should be ignored + struct OnlyMarker { + _a: (), + } + + // already non exhaustive, should be ignored + #[non_exhaustive] + struct NonExhaustive { + pub a: i32, + pub b: i32, + } +} + +mod tuple_structs { + struct T(pub i32, pub i32, ()); + + // some other fields are private, should be ignored + struct PrivateFields(pub i32, i32, ()); + + // private field is not unit type, should be ignored + struct NotUnit(pub i32, pub i32, i32); + + // private field is the only field, should be ignored + struct OnlyMarker(()); + + // already non exhaustive, should be ignored + #[non_exhaustive] + struct NonExhaustive(pub i32, pub i32); +} + +fn main() {} diff --git a/tests/ui/manual_non_exhaustive.stderr b/tests/ui/manual_non_exhaustive.stderr new file mode 100644 index 000000000000..d6719bca0d4c --- /dev/null +++ b/tests/ui/manual_non_exhaustive.stderr @@ -0,0 +1,48 @@ +error: this seems like a manual implementation of the non-exhaustive pattern + --> $DIR/manual_non_exhaustive.rs:5:5 + | +LL | / enum E { +LL | | A, +LL | | B, +LL | | #[doc(hidden)] +LL | | _C, +LL | | } + | |_____^ help: add the attribute: `#[non_exhaustive] enum E` + | + = note: `-D clippy::manual-non-exhaustive` implied by `-D warnings` +help: and remove this variant + --> $DIR/manual_non_exhaustive.rs:9:9 + | +LL | _C, + | ^^ + +error: this seems like a manual implementation of the non-exhaustive pattern + --> $DIR/manual_non_exhaustive.rs:67:5 + | +LL | / struct S { +LL | | pub a: i32, +LL | | pub b: i32, +LL | | _c: (), +LL | | } + | |_____^ help: add the attribute: `#[non_exhaustive] struct S` + | +help: and remove this field + --> $DIR/manual_non_exhaustive.rs:70:9 + | +LL | _c: (), + | ^^^^^^ + +error: this seems like a manual implementation of the non-exhaustive pattern + --> $DIR/manual_non_exhaustive.rs:108:5 + | +LL | struct T(pub i32, pub i32, ()); + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: add the attribute: `#[non_exhaustive] struct T` + | +help: and remove this field + --> $DIR/manual_non_exhaustive.rs:108:32 + | +LL | struct T(pub i32, pub i32, ()); + | ^^ + +error: aborting due to 3 previous errors + From 42b0b4754c881101cefb0307c489d6159c19b2f3 Mon Sep 17 00:00:00 2001 From: Eduardo Broto Date: Fri, 1 May 2020 22:37:14 +0200 Subject: [PATCH 2/3] Apply suggestions from PR review --- clippy_lints/src/manual_non_exhaustive.rs | 84 ++++++++++++----------- tests/ui/manual_non_exhaustive.rs | 39 +++++++---- tests/ui/manual_non_exhaustive.stderr | 81 ++++++++++++++++++---- 3 files changed, 139 insertions(+), 65 deletions(-) diff --git a/clippy_lints/src/manual_non_exhaustive.rs b/clippy_lints/src/manual_non_exhaustive.rs index ca2a2cf2e1e7..a4273da1d741 100644 --- a/clippy_lints/src/manual_non_exhaustive.rs +++ b/clippy_lints/src/manual_non_exhaustive.rs @@ -1,10 +1,11 @@ use crate::utils::{snippet_opt, span_lint_and_then}; use if_chain::if_chain; -use rustc_ast::ast::{Attribute, Ident, Item, ItemKind, StructField, TyKind, Variant, VariantData, VisibilityKind}; +use rustc_ast::ast::{Attribute, Item, ItemKind, StructField, Variant, VariantData, VisibilityKind}; use rustc_attr as attr; use rustc_errors::Applicability; use rustc_lint::{EarlyContext, EarlyLintPass}; use rustc_session::{declare_lint_pass, declare_tool_lint}; +use rustc_span::Span; declare_clippy_lint! { /// **What it does:** Checks for manual implementations of the non-exhaustive pattern. @@ -90,11 +91,9 @@ fn check_manual_non_exhaustive_enum(cx: &EarlyContext<'_>, item: &Item, variants } if_chain! { - if !attr::contains_name(&item.attrs, sym!(non_exhaustive)); - let markers = variants.iter().filter(|v| is_non_exhaustive_marker(v)).count(); - if markers == 1 && variants.len() > markers; - if let Some(variant) = variants.last(); - if is_non_exhaustive_marker(variant); + let mut markers = variants.iter().filter(|v| is_non_exhaustive_marker(v)); + if let Some(marker) = markers.next(); + if markers.count() == 0 && variants.len() > 1; then { span_lint_and_then( cx, @@ -102,17 +101,20 @@ fn check_manual_non_exhaustive_enum(cx: &EarlyContext<'_>, item: &Item, variants item.span, "this seems like a manual implementation of the non-exhaustive pattern", |diag| { - let header_span = cx.sess.source_map().span_until_char(item.span, '{'); - - if let Some(snippet) = snippet_opt(cx, header_span) { - diag.span_suggestion( - item.span, - "add the attribute", - format!("#[non_exhaustive] {}", snippet), - Applicability::Unspecified, - ); - diag.span_help(variant.span, "and remove this variant"); + if_chain! { + if !attr::contains_name(&item.attrs, sym!(non_exhaustive)); + let header_span = cx.sess.source_map().span_until_char(item.span, '{'); + if let Some(snippet) = snippet_opt(cx, header_span); + then { + diag.span_suggestion( + header_span, + "add the attribute", + format!("#[non_exhaustive] {}", snippet), + Applicability::Unspecified, + ); + } } + diag.span_help(marker.span, "remove this variant"); }); } } @@ -123,8 +125,18 @@ fn check_manual_non_exhaustive_struct(cx: &EarlyContext<'_>, item: &Item, data: matches!(field.vis.node, VisibilityKind::Inherited) } - fn is_non_exhaustive_marker(name: &Option) -> bool { - name.map(|n| n.as_str().starts_with('_')).unwrap_or(true) + fn is_non_exhaustive_marker(field: &StructField) -> bool { + is_private(field) && field.ty.kind.is_unit() && field.ident.map_or(true, |n| n.as_str().starts_with('_')) + } + + fn find_header_span(cx: &EarlyContext<'_>, item: &Item, data: &VariantData) -> Span { + let delimiter = match data { + VariantData::Struct(..) => '{', + VariantData::Tuple(..) => '(', + _ => unreachable!("`VariantData::Unit` is already handled above"), + }; + + cx.sess.source_map().span_until_char(item.span, delimiter) } let fields = data.fields(); @@ -132,12 +144,8 @@ fn check_manual_non_exhaustive_struct(cx: &EarlyContext<'_>, item: &Item, data: let public_fields = fields.iter().filter(|f| f.vis.node.is_pub()).count(); if_chain! { - if !attr::contains_name(&item.attrs, sym!(non_exhaustive)); - if private_fields == 1 && public_fields >= private_fields && public_fields == fields.len() - 1; - if let Some(field) = fields.iter().find(|f| is_private(f)); - if is_non_exhaustive_marker(&field.ident); - if let TyKind::Tup(tup_fields) = &field.ty.kind; - if tup_fields.is_empty(); + if private_fields == 1 && public_fields >= 1 && public_fields == fields.len() - 1; + if let Some(marker) = fields.iter().find(|f| is_non_exhaustive_marker(f)); then { span_lint_and_then( cx, @@ -145,22 +153,20 @@ fn check_manual_non_exhaustive_struct(cx: &EarlyContext<'_>, item: &Item, data: item.span, "this seems like a manual implementation of the non-exhaustive pattern", |diag| { - let delimiter = match data { - VariantData::Struct(..) => '{', - VariantData::Tuple(..) => '(', - _ => unreachable!(), - }; - let header_span = cx.sess.source_map().span_until_char(item.span, delimiter); - - if let Some(snippet) = snippet_opt(cx, header_span) { - diag.span_suggestion( - item.span, - "add the attribute", - format!("#[non_exhaustive] {}", snippet), - Applicability::Unspecified, - ); - diag.span_help(field.span, "and remove this field"); + if_chain! { + if !attr::contains_name(&item.attrs, sym!(non_exhaustive)); + let header_span = find_header_span(cx, item, data); + if let Some(snippet) = snippet_opt(cx, header_span); + then { + diag.span_suggestion( + header_span, + "add the attribute", + format!("#[non_exhaustive] {}", snippet), + Applicability::Unspecified, + ); + } } + diag.span_help(marker.span, "remove this field"); }); } } diff --git a/tests/ui/manual_non_exhaustive.rs b/tests/ui/manual_non_exhaustive.rs index 9c239db6e00d..7a788f485207 100644 --- a/tests/ui/manual_non_exhaustive.rs +++ b/tests/ui/manual_non_exhaustive.rs @@ -9,7 +9,16 @@ mod enums { _C, } - // last variant does not have doc hidden attribute, should be ignored + // user forgot to remove the marker + #[non_exhaustive] + enum Ep { + A, + B, + #[doc(hidden)] + _C, + } + + // marker variant does not have doc hidden attribute, should be ignored enum NoDocHidden { A, B, @@ -32,21 +41,13 @@ mod enums { _C(bool), } - // variant with doc hidden is not the last one, should be ignored - enum NotLast { - A, - #[doc(hidden)] - _B, - C, - } - // variant with doc hidden is the only one, should be ignored enum OnlyMarker { #[doc(hidden)] _A, } - // variant with multiple non-exhaustive "markers", should be ignored + // variant with multiple markers, should be ignored enum MultipleMarkers { A, #[doc(hidden)] @@ -55,7 +56,7 @@ mod enums { _C, } - // already non_exhaustive, should be ignored + // already non_exhaustive and no markers, should be ignored #[non_exhaustive] enum NonExhaustive { A, @@ -70,6 +71,14 @@ mod structs { _c: (), } + // user forgot to remove the private field + #[non_exhaustive] + struct Sp { + pub a: i32, + pub b: i32, + _c: (), + } + // some other fields are private, should be ignored struct PrivateFields { a: i32, @@ -96,7 +105,7 @@ mod structs { _a: (), } - // already non exhaustive, should be ignored + // already non exhaustive and no private fields, should be ignored #[non_exhaustive] struct NonExhaustive { pub a: i32, @@ -107,6 +116,10 @@ mod structs { mod tuple_structs { struct T(pub i32, pub i32, ()); + // user forgot to remove the private field + #[non_exhaustive] + struct Tp(pub i32, pub i32, ()); + // some other fields are private, should be ignored struct PrivateFields(pub i32, i32, ()); @@ -116,7 +129,7 @@ mod tuple_structs { // private field is the only field, should be ignored struct OnlyMarker(()); - // already non exhaustive, should be ignored + // already non exhaustive and no private fields, should be ignored #[non_exhaustive] struct NonExhaustive(pub i32, pub i32); } diff --git a/tests/ui/manual_non_exhaustive.stderr b/tests/ui/manual_non_exhaustive.stderr index d6719bca0d4c..613c5e8ca1d4 100644 --- a/tests/ui/manual_non_exhaustive.stderr +++ b/tests/ui/manual_non_exhaustive.stderr @@ -1,48 +1,103 @@ error: this seems like a manual implementation of the non-exhaustive pattern --> $DIR/manual_non_exhaustive.rs:5:5 | -LL | / enum E { +LL | enum E { + | ^----- + | | + | _____help: add the attribute: `#[non_exhaustive] enum E` + | | LL | | A, LL | | B, LL | | #[doc(hidden)] LL | | _C, LL | | } - | |_____^ help: add the attribute: `#[non_exhaustive] enum E` + | |_____^ | = note: `-D clippy::manual-non-exhaustive` implied by `-D warnings` -help: and remove this variant +help: remove this variant --> $DIR/manual_non_exhaustive.rs:9:9 | LL | _C, | ^^ error: this seems like a manual implementation of the non-exhaustive pattern - --> $DIR/manual_non_exhaustive.rs:67:5 + --> $DIR/manual_non_exhaustive.rs:14:5 | -LL | / struct S { +LL | / enum Ep { +LL | | A, +LL | | B, +LL | | #[doc(hidden)] +LL | | _C, +LL | | } + | |_____^ + | +help: remove this variant + --> $DIR/manual_non_exhaustive.rs:18:9 + | +LL | _C, + | ^^ + +error: this seems like a manual implementation of the non-exhaustive pattern + --> $DIR/manual_non_exhaustive.rs:68:5 + | +LL | struct S { + | ^------- + | | + | _____help: add the attribute: `#[non_exhaustive] struct S` + | | +LL | | pub a: i32, +LL | | pub b: i32, +LL | | _c: (), +LL | | } + | |_____^ + | +help: remove this field + --> $DIR/manual_non_exhaustive.rs:71:9 + | +LL | _c: (), + | ^^^^^^ + +error: this seems like a manual implementation of the non-exhaustive pattern + --> $DIR/manual_non_exhaustive.rs:76:5 + | +LL | / struct Sp { LL | | pub a: i32, LL | | pub b: i32, LL | | _c: (), LL | | } - | |_____^ help: add the attribute: `#[non_exhaustive] struct S` + | |_____^ | -help: and remove this field - --> $DIR/manual_non_exhaustive.rs:70:9 +help: remove this field + --> $DIR/manual_non_exhaustive.rs:79:9 | LL | _c: (), | ^^^^^^ error: this seems like a manual implementation of the non-exhaustive pattern - --> $DIR/manual_non_exhaustive.rs:108:5 + --> $DIR/manual_non_exhaustive.rs:117:5 | LL | struct T(pub i32, pub i32, ()); - | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: add the attribute: `#[non_exhaustive] struct T` + | --------^^^^^^^^^^^^^^^^^^^^^^^ + | | + | help: add the attribute: `#[non_exhaustive] struct T` | -help: and remove this field - --> $DIR/manual_non_exhaustive.rs:108:32 +help: remove this field + --> $DIR/manual_non_exhaustive.rs:117:32 | LL | struct T(pub i32, pub i32, ()); | ^^ -error: aborting due to 3 previous errors +error: this seems like a manual implementation of the non-exhaustive pattern + --> $DIR/manual_non_exhaustive.rs:121:5 + | +LL | struct Tp(pub i32, pub i32, ()); + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + | +help: remove this field + --> $DIR/manual_non_exhaustive.rs:121:33 + | +LL | struct Tp(pub i32, pub i32, ()); + | ^^ + +error: aborting due to 6 previous errors From 350c17de24c0bc7ee1b17981fe02f88ca6ec50a4 Mon Sep 17 00:00:00 2001 From: ebroto Date: Fri, 1 May 2020 23:00:16 +0200 Subject: [PATCH 3/3] Use the only variant left instead of a wildcard Co-authored-by: Philipp Krones --- clippy_lints/src/manual_non_exhaustive.rs | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/clippy_lints/src/manual_non_exhaustive.rs b/clippy_lints/src/manual_non_exhaustive.rs index a4273da1d741..f3b8902e26f6 100644 --- a/clippy_lints/src/manual_non_exhaustive.rs +++ b/clippy_lints/src/manual_non_exhaustive.rs @@ -133,7 +133,7 @@ fn check_manual_non_exhaustive_struct(cx: &EarlyContext<'_>, item: &Item, data: let delimiter = match data { VariantData::Struct(..) => '{', VariantData::Tuple(..) => '(', - _ => unreachable!("`VariantData::Unit` is already handled above"), + VariantData::Unit(_) => unreachable!("`VariantData::Unit` is already handled above"), }; cx.sess.source_map().span_until_char(item.span, delimiter)