diff options
Diffstat (limited to 'src/tools/clippy/clippy_lints/src/partial_pub_fields.rs')
-rw-r--r-- | src/tools/clippy/clippy_lints/src/partial_pub_fields.rs | 81 |
1 files changed, 81 insertions, 0 deletions
diff --git a/src/tools/clippy/clippy_lints/src/partial_pub_fields.rs b/src/tools/clippy/clippy_lints/src/partial_pub_fields.rs new file mode 100644 index 000000000..f60d9d65b --- /dev/null +++ b/src/tools/clippy/clippy_lints/src/partial_pub_fields.rs @@ -0,0 +1,81 @@ +use clippy_utils::diagnostics::span_lint_and_help; +use rustc_ast::ast::{Item, ItemKind}; +use rustc_lint::{EarlyContext, EarlyLintPass}; +use rustc_session::{declare_lint_pass, declare_tool_lint}; + +declare_clippy_lint! { + /// ### What it does + /// Checks whether partial fields of a struct are public. + /// + /// Either make all fields of a type public, or make none of them public + /// + /// ### Why is this bad? + /// Most types should either be: + /// * Abstract data types: complex objects with opaque implementation which guard + /// interior invariants and expose intentionally limited API to the outside world. + /// * Data: relatively simple objects which group a bunch of related attributes together. + /// + /// ### Example + /// ```rust + /// pub struct Color { + /// pub r: u8, + /// pub g: u8, + /// b: u8, + /// } + /// ``` + /// Use instead: + /// ```rust + /// pub struct Color { + /// pub r: u8, + /// pub g: u8, + /// pub b: u8, + /// } + /// ``` + #[clippy::version = "1.66.0"] + pub PARTIAL_PUB_FIELDS, + restriction, + "partial fields of a struct are public" +} +declare_lint_pass!(PartialPubFields => [PARTIAL_PUB_FIELDS]); + +impl EarlyLintPass for PartialPubFields { + fn check_item(&mut self, cx: &EarlyContext<'_>, item: &Item) { + let ItemKind::Struct(ref st, _) = item.kind else { + return; + }; + + let mut fields = st.fields().iter(); + let Some(first_field) = fields.next() else { + // Empty struct. + return; + }; + let all_pub = first_field.vis.kind.is_pub(); + let all_priv = !all_pub; + + let msg = "mixed usage of pub and non-pub fields"; + + for field in fields { + if all_priv && field.vis.kind.is_pub() { + span_lint_and_help( + cx, + PARTIAL_PUB_FIELDS, + field.vis.span, + msg, + None, + "consider using private field here", + ); + return; + } else if all_pub && !field.vis.kind.is_pub() { + span_lint_and_help( + cx, + PARTIAL_PUB_FIELDS, + field.vis.span, + msg, + None, + "consider using public field here", + ); + return; + } + } + } +} |