[wildcard_imports] Modules that contain prelude are also allowed

This commit fixes rust-lang#10846 by checking if the path segment contains the
word "prelude".

Signed-off-by: Charalampos Mitrodimas <charmitro@gmail.com>

Author: charmitro

clippy_lints/src/wildcard_imports.rs

@@ -65,8 +65,9 @@ declare_clippy_lint! {
     /// This can lead to confusing error messages at best and to unexpected behavior at worst.
     ///
     /// ### Exceptions
-    /// Wildcard imports are allowed from modules named `prelude`. Many crates (including the standard library)
-    /// provide modules named "prelude" specifically designed for wildcard import.
+    /// Wildcard imports are allowed from modules that their name contains `prelude`. Many crates
+    /// (including the standard library) provide modules named "prelude" specifically designed
+    /// for wildcard import.
     ///
     /// `use super::*` is allowed in test modules. This is defined as any module with "test" in the name.
     ///
@@ -212,7 +213,9 @@ impl WildcardImports {
 // Allow "...prelude::..::*" imports.
 // Many crates have a prelude, and it is imported as a glob by design.
 fn is_prelude_import(segments: &[PathSegment<'_>]) -> bool {
-    segments.iter().any(|ps| ps.ident.name == sym::prelude)
+    segments
+        .iter()
+        .any(|ps| ps.ident.name.as_str().contains(sym::prelude.as_str()))
 }
 
 // Allow "super::*" imports in tests.

tests/ui/auxiliary/wildcard_imports_helper.rs

@@ -25,3 +25,9 @@ pub mod prelude {
         pub struct PreludeModAnywhere;
     }
 }
+
+pub mod extern_prelude {
+    pub mod v1 {
+        pub struct ExternPreludeModAnywhere;
+    }
+}

tests/ui/wildcard_imports.fixed

@@ -24,6 +24,7 @@ use wildcard_imports_helper::inner::inner_for_self_import::inner_extern_bar;
 use wildcard_imports_helper::{ExternA, extern_foo};
 
 use std::io::prelude::*;
+use wildcard_imports_helper::extern_prelude::v1::*;
 use wildcard_imports_helper::prelude::v1::*;
 
 struct ReadFoo;
@@ -81,6 +82,7 @@ fn main() {
     let _ = inner_struct_mod::C;
     let _ = ExternA;
     let _ = PreludeModAnywhere;
+    let _ = ExternPreludeModAnywhere;
 
     double_struct_import_test!();
     double_struct_import_test!();

tests/ui/wildcard_imports.rs

@@ -24,6 +24,7 @@ use wildcard_imports_helper::inner::inner_for_self_import::*;
 use wildcard_imports_helper::*;
 
 use std::io::prelude::*;
+use wildcard_imports_helper::extern_prelude::v1::*;
 use wildcard_imports_helper::prelude::v1::*;
 
 struct ReadFoo;
@@ -81,6 +82,7 @@ fn main() {
     let _ = inner_struct_mod::C;
     let _ = ExternA;
     let _ = PreludeModAnywhere;
+    let _ = ExternPreludeModAnywhere;
 
     double_struct_import_test!();
     double_struct_import_test!();

tests/ui/wildcard_imports.stderr

@@ -37,93 +37,93 @@ LL | use wildcard_imports_helper::*;
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `wildcard_imports_helper::{ExternA, extern_foo}`
 
 error: usage of wildcard import
-  --> $DIR/wildcard_imports.rs:95:13
+  --> $DIR/wildcard_imports.rs:97:13
    |
 LL |         use crate::fn_mod::*;
    |             ^^^^^^^^^^^^^^^^ help: try: `crate::fn_mod::foo`
 
 error: usage of wildcard import
-  --> $DIR/wildcard_imports.rs:101:75
+  --> $DIR/wildcard_imports.rs:103:75
    |
 LL |         use wildcard_imports_helper::inner::inner_for_self_import::{self, *};
    |                                                                           ^ help: try: `inner_extern_foo`
 
 error: usage of wildcard import
-  --> $DIR/wildcard_imports.rs:102:13
+  --> $DIR/wildcard_imports.rs:104:13
    |
 LL |         use wildcard_imports_helper::*;
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `wildcard_imports_helper::{ExternA, extern_foo}`
 
 error: usage of wildcard import
-  --> $DIR/wildcard_imports.rs:113:20
+  --> $DIR/wildcard_imports.rs:115:20
    |
 LL |         use self::{inner::*, inner2::*};
    |                    ^^^^^^^^ help: try: `inner::inner_foo`
 
 error: usage of wildcard import
-  --> $DIR/wildcard_imports.rs:113:30
+  --> $DIR/wildcard_imports.rs:115:30
    |
 LL |         use self::{inner::*, inner2::*};
    |                              ^^^^^^^^^ help: try: `inner2::inner_bar`
 
 error: usage of wildcard import
-  --> $DIR/wildcard_imports.rs:120:13
+  --> $DIR/wildcard_imports.rs:122:13
    |
 LL |         use wildcard_imports_helper::*;
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `wildcard_imports_helper::{ExternExportedEnum, ExternExportedStruct, extern_exported}`
 
 error: usage of wildcard import
-  --> $DIR/wildcard_imports.rs:149:9
+  --> $DIR/wildcard_imports.rs:151:9
    |
 LL |     use crate::in_fn_test::*;
    |         ^^^^^^^^^^^^^^^^^^^^ help: try: `crate::in_fn_test::{ExportedEnum, ExportedStruct, exported}`
 
 error: usage of wildcard import
-  --> $DIR/wildcard_imports.rs:158:9
+  --> $DIR/wildcard_imports.rs:160:9
    |
 LL |     use crate:: in_fn_test::  * ;
    |         ^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `crate:: in_fn_test::exported`
 
 error: usage of wildcard import
-  --> $DIR/wildcard_imports.rs:159:9
+  --> $DIR/wildcard_imports.rs:161:9
    |
 LL |       use crate:: fn_mod::
    |  _________^
 LL | |         *;
    | |_________^ help: try: `crate:: fn_mod::foo`
 
 error: usage of wildcard import
-  --> $DIR/wildcard_imports.rs:170:13
+  --> $DIR/wildcard_imports.rs:172:13
    |
 LL |         use super::*;
    |             ^^^^^^^^ help: try: `super::foofoo`
 
 error: usage of wildcard import
-  --> $DIR/wildcard_imports.rs:205:17
+  --> $DIR/wildcard_imports.rs:207:17
    |
 LL |             use super::*;
    |                 ^^^^^^^^ help: try: `super::insidefoo`
 
 error: usage of wildcard import
-  --> $DIR/wildcard_imports.rs:213:13
+  --> $DIR/wildcard_imports.rs:215:13
    |
 LL |         use super_imports::*;
    |             ^^^^^^^^^^^^^^^^ help: try: `super_imports::foofoo`
 
 error: usage of wildcard import
-  --> $DIR/wildcard_imports.rs:222:17
+  --> $DIR/wildcard_imports.rs:224:17
    |
 LL |             use super::super::*;
    |                 ^^^^^^^^^^^^^^^ help: try: `super::super::foofoo`
 
 error: usage of wildcard import
-  --> $DIR/wildcard_imports.rs:231:13
+  --> $DIR/wildcard_imports.rs:233:13
    |
 LL |         use super::super::super_imports::*;
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `super::super::super_imports::foofoo`
 
 error: usage of wildcard import
-  --> $DIR/wildcard_imports.rs:239:13
+  --> $DIR/wildcard_imports.rs:241:13
    |
 LL |         use super::*;
    |             ^^^^^^^^ help: try: `super::foofoo`