wip

doctest

Author: lengyijun

CHANGELOG.md

@@ -6212,6 +6212,7 @@ Released 2018-09-13
 [`unwrap_or_else_default`]: https://rust-lang.github.io/rust-clippy/master/index.html#unwrap_or_else_default
 [`unwrap_used`]: https://rust-lang.github.io/rust-clippy/master/index.html#unwrap_used
 [`upper_case_acronyms`]: https://rust-lang.github.io/rust-clippy/master/index.html#upper_case_acronyms
+[`use_crate_prefix_for_self_imports`]: https://rust-lang.github.io/rust-clippy/master/index.html#use_crate_prefix_for_self_imports
 [`use_debug`]: https://rust-lang.github.io/rust-clippy/master/index.html#use_debug
 [`use_self`]: https://rust-lang.github.io/rust-clippy/master/index.html#use_self
 [`used_underscore_binding`]: https://rust-lang.github.io/rust-clippy/master/index.html#used_underscore_binding

clippy_lints/src/declared_lints.rs

@@ -776,6 +776,7 @@ pub static LINTS: &[&crate::LintInfo] = &[
     crate::unwrap::UNNECESSARY_UNWRAP_INFO,
     crate::unwrap_in_result::UNWRAP_IN_RESULT_INFO,
     crate::upper_case_acronyms::UPPER_CASE_ACRONYMS_INFO,
+    crate::use_crate_prefix_for_self_imports::USE_CRATE_PREFIX_FOR_SELF_IMPORTS_INFO,
     crate::use_self::USE_SELF_INFO,
     crate::useless_conversion::USELESS_CONVERSION_INFO,
     crate::vec::USELESS_VEC_INFO,

clippy_lints/src/lib.rs

@@ -390,6 +390,7 @@ mod unused_unit;
 mod unwrap;
 mod unwrap_in_result;
 mod upper_case_acronyms;
+mod use_crate_prefix_for_self_imports;
 mod use_self;
 mod useless_conversion;
 mod vec;
@@ -976,5 +977,6 @@ pub fn register_lints(store: &mut rustc_lint::LintStore, conf: &'static Conf) {
     store.register_late_pass(|_| Box::new(unneeded_struct_pattern::UnneededStructPattern));
     store.register_late_pass(|_| Box::<unnecessary_semicolon::UnnecessarySemicolon>::default());
     store.register_late_pass(move |_| Box::new(non_std_lazy_statics::NonStdLazyStatic::new(conf)));
+    store.register_late_pass(|_| Box::new(use_crate_prefix_for_self_imports::UseCratePrefixForSelfImports));
     // add lints here, do not remove this comment, it's used in `new_lint`
 }

clippy_lints/src/use_crate_prefix_for_self_imports.rs

@@ -0,0 +1,76 @@
+use clippy_utils::diagnostics::span_lint_and_sugg;
+use clippy_utils::source::snippet_opt;
+use def_id::LOCAL_CRATE;
+use rustc_errors::Applicability;
+use rustc_hir::def::Res;
+use rustc_hir::*;
+use rustc_lint::{LateContext, LateLintPass};
+use rustc_session::declare_lint_pass;
+
+declare_clippy_lint! {
+    /// ### What it does
+    /// This lint checks for imports from the current crate that do not use the `crate::` prefix.
+    /// It suggests using `crate::` to make it clear that the item is from the same crate.
+    ///
+    /// ### Why is this bad?
+    /// When imports from the current crate lack the `crate::` prefix, it can make the code less readable
+    /// because it’s not immediately clear if the imported item is from the current crate or an external dependency.
+    /// Using `crate::` for self-imports provides a consistent style, making the origin of each import clear.
+    /// This helps reduce confusion and maintain a uniform codebase.
+    ///
+    /// ### Example
+    /// ```rust,ignore
+    /// // lib.rs
+    /// mod foo;
+    /// use foo::bar;
+    /// ```
+    ///
+    /// ```rust,ignore
+    /// // foo.rs
+    /// #[path = "./foo.rs"]
+    /// pub fn bar() {}
+    /// ```
+    ///
+    /// Use instead:
+    /// ```rust,ignore
+    /// // lib.rs
+    /// mod foo;
+    /// use crate::foo::bar;
+    /// ```
+    ///
+    /// ```rust,ignore
+    /// // foo.rs
+    /// #[path = "./foo.rs"]
+    /// pub fn bar() {}
+    /// ```
+    #[clippy::version = "1.84.0"]
+    pub USE_CRATE_PREFIX_FOR_SELF_IMPORTS,
+    style,
+    "checks that imports from the current crate use the `crate::` prefix"
+}
+
+declare_lint_pass!(UseCratePrefixForSelfImports => [USE_CRATE_PREFIX_FOR_SELF_IMPORTS]);
+
+impl LateLintPass<'_> for UseCratePrefixForSelfImports {
+    fn check_item(&mut self, cx: &LateContext<'_>, item: &Item<'_>) {
+        if let ItemKind::Use(use_path, _) = &item.kind {
+            if let Some(segment) = use_path.segments.first()
+                && let Res::Def(_, def_id) = segment.res
+                && def_id.krate == LOCAL_CRATE
+            {
+                let root = segment.ident.name;
+                if root != rustc_span::symbol::kw::Crate && root != rustc_span::symbol::kw::Super {
+                    span_lint_and_sugg(
+                        cx,
+                        USE_CRATE_PREFIX_FOR_SELF_IMPORTS,
+                        use_path.span,
+                        "this import is not clear",
+                        "prefix with `crate::`",
+                        format!("crate::{}", snippet_opt(cx, use_path.span).unwrap()),
+                        Applicability::MachineApplicable,
+                    );
+                }
+            }
+        }
+    }
+}

tests/ui-cargo/use_crate_prefix_for_self_imports/fail/Cargo.stderr

@@ -0,0 +1,10 @@
+error: this import is not clear
+ --> src/main.rs:1:5
+  |
+1 | use foo::Foo;
+  |     ^^^^^^^^ help: prefix with `crate::`: `crate::foo::Foo`
+  |
+  = note: `-D clippy::use-crate-prefix-for-self-imports` implied by `-D warnings`
+  = help: to override `-D warnings` add `#[allow(clippy::use_crate_prefix_for_self_imports)]`
+
+error: could not compile `fail` (bin "fail") due to 1 previous error

tests/ui-cargo/use_crate_prefix_for_self_imports/fail/Cargo.toml

@@ -0,0 +1,7 @@
+[package]
+name = "fail"
+version = "0.1.0"
+edition = "2021"
+publish = false
+
+[dependencies]

tests/ui-cargo/use_crate_prefix_for_self_imports/fail/src/foo.rs

@@ -0,0 +1 @@
+pub struct Foo;

tests/ui-cargo/use_crate_prefix_for_self_imports/fail/src/main.rs

@@ -0,0 +1,7 @@
+use foo::Foo;
+
+mod foo;
+
+fn main() {
+    let _foo = Foo;
+}

tests/ui-cargo/use_crate_prefix_for_self_imports/pass/Cargo.toml

@@ -0,0 +1,7 @@
+[package]
+name = "pass"
+version = "0.1.0"
+edition = "2021"
+publish = false
+
+[dependencies]

tests/ui-cargo/use_crate_prefix_for_self_imports/pass/src/foo.rs

@@ -0,0 +1 @@
+pub struct Foo;