Add check for "test" in parent name. Include flag for disabling wildcard import exceptions

clippy_lints/src/lib.rs

@@ -1058,7 +1058,8 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
     let max_struct_bools = conf.max_struct_bools;
     store.register_early_pass(move || box excessive_bools::ExcessiveBools::new(max_struct_bools, max_fn_params_bools));
     store.register_early_pass(|| box option_env_unwrap::OptionEnvUnwrap);
-    store.register_late_pass(|| box wildcard_imports::WildcardImports);
+    let warn_on_all_wildcard_imports = conf.warn_on_all_wildcard_imports;
+    store.register_late_pass(move || box wildcard_imports::WildcardImports::new(warn_on_all_wildcard_imports));
     store.register_early_pass(|| box macro_use::MacroUseImports);
     store.register_late_pass(|| box verbose_file_reads::VerboseFileReads);
     store.register_late_pass(|| box redundant_pub_crate::RedundantPubCrate::default());

clippy_lints/src/utils/conf.rs

@@ -158,6 +158,8 @@ define_Conf! {
     (max_struct_bools, "max_struct_bools": u64, 3),
     /// Lint: FN_PARAMS_EXCESSIVE_BOOLS. The maximum number of bools function parameters can have
     (max_fn_params_bools, "max_fn_params_bools": u64, 3),
+    /// Lint: WILDCARD_IMPORTS. Whether to allow certain wildcard imports (prelude, super in tests).
+    (warn_on_all_wildcard_imports, "warn_on_all_wildcard_imports": bool, false),
 }
 
 impl Default for Conf {

clippy_lints/src/wildcard_imports.rs

@@ -6,7 +6,7 @@ use rustc_hir::{
     Item, ItemKind, PathSegment, UseKind,
 };
 use rustc_lint::{LateContext, LateLintPass};
-use rustc_session::{declare_lint_pass, declare_tool_lint};
+use rustc_session::{declare_tool_lint, impl_lint_pass};
 use rustc_span::BytePos;
 
 declare_clippy_lint! {
@@ -73,18 +73,38 @@ declare_clippy_lint! {
     "lint `use _::*` statements"
 }
 
-declare_lint_pass!(WildcardImports => [ENUM_GLOB_USE, WILDCARD_IMPORTS]);
+#[derive(Default)]
+pub struct WildcardImports {
+    warn_on_all: bool,
+    is_test_module: bool,
+    test_modules_deep: u32,
+}
+
+impl WildcardImports {
+    pub fn new(warn_on_all: bool) -> Self {
+        Self {
+            warn_on_all,
+            is_test_module: false,
+            test_modules_deep: 0,
+        }
+    }
+}
+
+impl_lint_pass!(WildcardImports => [ENUM_GLOB_USE, WILDCARD_IMPORTS]);
 
 impl LateLintPass<'_, '_> for WildcardImports {
     fn check_item(&mut self, cx: &LateContext<'_, '_>, item: &Item<'_>) {
         if item.vis.node.is_pub() || item.vis.node.is_pub_restricted() {
             return;
         }
+        if is_test_module(item) {
+            self.is_test_module = true;
+            self.test_modules_deep += 1;
+        }
         if_chain! {
             if !in_macro(item.span);
             if let ItemKind::Use(use_path, UseKind::Glob) = &item.kind;
-            if !is_prelude_import(use_path.segments);
-            if !(is_super_only_import(use_path.segments) && is_in_test_module(cx, item));
+            if self.warn_on_all || !self.check_exceptions(use_path.segments);
             let used_imports = cx.tcx.names_imported_by_glob_use(item.hir_id.owner);
             if !used_imports.is_empty(); // Already handled by `unused_imports`
             then {
@@ -152,6 +172,19 @@ impl LateLintPass<'_, '_> for WildcardImports {
             }
         }
     }
+
+    fn check_item_post(&mut self, _: &LateContext<'_, '_>, _: &Item<'_>) {
+        if self.is_test_module {
+            self.is_test_module = false;
+            self.test_modules_deep -= 1;
+        }
+    }
+}
+
+impl WildcardImports {
+    fn check_exceptions(&self, segments: &[PathSegment<'_>]) -> bool {
+        is_prelude_import(segments) || (is_super_only_import(segments) && self.test_modules_deep > 0)
+    }
 }
 
 // Allow "...prelude::*" imports.
@@ -168,9 +201,6 @@ fn is_super_only_import(segments: &[PathSegment<'_>]) -> bool {
     segments.len() == 1 && segments[0].ident.as_str() == "super"
 }
 
-fn is_in_test_module(cx: &LateContext<'_, '_>, item: &Item<'_>) -> bool {
-    let parent = cx.tcx.hir().get_parent_node(item.hir_id);
-    let parent_item = cx.tcx.hir().expect_item(parent);
-    let parent_name = parent_item.ident.name.as_str();
-    parent_name.contains("test")
+fn is_test_module(item: &Item<'_>) -> bool {
+    item.ident.name.as_str().contains("test")
 }

tests/ui-toml/toml_unknown_key/conf_unknown_key.stderr

@@ -1,4 +1,4 @@
-error: error reading Clippy's configuration file `$DIR/clippy.toml`: unknown field `foobar`, expected one of `blacklisted-names`, `cognitive-complexity-threshold`, `cyclomatic-complexity-threshold`, `doc-valid-idents`, `too-many-arguments-threshold`, `type-complexity-threshold`, `single-char-binding-names-threshold`, `too-large-for-stack`, `enum-variant-name-threshold`, `enum-variant-size-threshold`, `verbose-bit-mask-threshold`, `literal-representation-threshold`, `trivial-copy-size-limit`, `too-many-lines-threshold`, `array-size-threshold`, `vec-box-size-threshold`, `max-struct-bools`, `max-fn-params-bools`, `third-party` at line 5 column 1
+error: error reading Clippy's configuration file `$DIR/clippy.toml`: unknown field `foobar`, expected one of `blacklisted-names`, `cognitive-complexity-threshold`, `cyclomatic-complexity-threshold`, `doc-valid-idents`, `too-many-arguments-threshold`, `type-complexity-threshold`, `single-char-binding-names-threshold`, `too-large-for-stack`, `enum-variant-name-threshold`, `enum-variant-size-threshold`, `verbose-bit-mask-threshold`, `literal-representation-threshold`, `trivial-copy-size-limit`, `too-many-lines-threshold`, `array-size-threshold`, `vec-box-size-threshold`, `max-struct-bools`, `max-fn-params-bools`, `warn-on-all-wildcard-imports`, `third-party` at line 5 column 1
 
 error: aborting due to previous error
 

tests/ui/wildcard_imports.fixed

@@ -156,10 +156,10 @@ fn test_weird_formatting() {
     foo();
 }
 
-mod test_super_imports {
+mod super_imports {
     fn foofoo() {}
 
-    mod use_super_should_be_replaced {
+    mod should_be_replaced {
         use super::foofoo;
 
         fn with_super() {
@@ -167,7 +167,7 @@ mod test_super_imports {
         }
     }
 
-    mod use_super_in_test_should_pass {
+    mod test_should_pass {
         use super::*;
 
         fn with_super() {
@@ -175,8 +175,15 @@ mod test_super_imports {
         }
     }
 
+    mod inner {
+        fn test_should_pass() {
+            use super::*;
+            let _ = foofoo();
+        }
+    }
+
     mod use_explicit_should_be_replaced {
-        use test_super_imports::foofoo;
+        use super_imports::foofoo;
 
         fn with_explicit() {
             let _ = foofoo();
@@ -194,7 +201,7 @@ mod test_super_imports {
     }
 
     mod use_super_explicit_should_be_replaced {
-        use super::super::test_super_imports::foofoo;
+        use super::super::super_imports::foofoo;
 
         fn with_super_explicit() {
             let _ = foofoo();

tests/ui/wildcard_imports.rs

@@ -157,10 +157,10 @@ fn test_weird_formatting() {
     foo();
 }
 
-mod test_super_imports {
+mod super_imports {
     fn foofoo() {}
 
-    mod use_super_should_be_replaced {
+    mod should_be_replaced {
         use super::*;
 
         fn with_super() {
@@ -168,7 +168,7 @@ mod test_super_imports {
         }
     }
 
-    mod use_super_in_test_should_pass {
+    mod test_should_pass {
         use super::*;
 
         fn with_super() {
@@ -176,8 +176,15 @@ mod test_super_imports {
         }
     }
 
+    mod inner {
+        fn test_should_pass() {
+            use super::*;
+            let _ = foofoo();
+        }
+    }
+
     mod use_explicit_should_be_replaced {
-        use test_super_imports::*;
+        use super_imports::*;
 
         fn with_explicit() {
             let _ = foofoo();
@@ -195,7 +202,7 @@ mod test_super_imports {
     }
 
     mod use_super_explicit_should_be_replaced {
-        use super::super::test_super_imports::*;
+        use super::super::super_imports::*;
 
         fn with_super_explicit() {
             let _ = foofoo();

tests/ui/wildcard_imports.stderr

@@ -99,22 +99,22 @@ LL |         use super::*;
    |             ^^^^^^^^ help: try: `super::foofoo`
 
 error: usage of wildcard import
-  --> $DIR/wildcard_imports.rs:180:13
+  --> $DIR/wildcard_imports.rs:187:13
    |
-LL |         use test_super_imports::*;
-   |             ^^^^^^^^^^^^^^^^^^^^^ help: try: `test_super_imports::foofoo`
+LL |         use super_imports::*;
+   |             ^^^^^^^^^^^^^^^^ help: try: `super_imports::foofoo`
 
 error: usage of wildcard import
-  --> $DIR/wildcard_imports.rs:189:17
+  --> $DIR/wildcard_imports.rs:196:17
    |
 LL |             use super::super::*;
    |                 ^^^^^^^^^^^^^^^ help: try: `super::super::foofoo`
 
 error: usage of wildcard import
-  --> $DIR/wildcard_imports.rs:198:13
+  --> $DIR/wildcard_imports.rs:205:13
    |
-LL |         use super::super::test_super_imports::*;
-   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `super::super::test_super_imports::foofoo`
+LL |         use super::super::super_imports::*;
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `super::super::super_imports::foofoo`
 
 error: aborting due to 19 previous errors