From 0c14ea8ed79ebf0b7368659282136e876f247cc9 Mon Sep 17 00:00:00 2001
From: Glenn Hope <glenn.alexander.hope@gmail.com>
Date: Sun, 3 May 2020 10:56:25 -0700
Subject: [PATCH 01/10] Allow 'use super::*;' imports

---
 clippy_lints/src/wildcard_imports.rs | 19 +++++++++++---
 tests/ui/wildcard_imports.fixed      | 38 ++++++++++++++++++++++++++++
 tests/ui/wildcard_imports.rs         | 38 ++++++++++++++++++++++++++++
 tests/ui/wildcard_imports.stderr     | 20 ++++++++++++++-
 4 files changed, 111 insertions(+), 4 deletions(-)

diff --git a/clippy_lints/src/wildcard_imports.rs b/clippy_lints/src/wildcard_imports.rs
index f3038861cee2..70ad9a60a02c 100644
--- a/clippy_lints/src/wildcard_imports.rs
+++ b/clippy_lints/src/wildcard_imports.rs
@@ -3,7 +3,7 @@ use if_chain::if_chain;
 use rustc_errors::Applicability;
 use rustc_hir::{
     def::{DefKind, Res},
-    Item, ItemKind, UseKind,
+    Item, ItemKind, PathSegment, UseKind,
 };
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_session::{declare_lint_pass, declare_tool_lint};
@@ -83,8 +83,8 @@ impl LateLintPass<'_, '_> for WildcardImports {
         if_chain! {
             if !in_macro(item.span);
             if let ItemKind::Use(use_path, UseKind::Glob) = &item.kind;
-            // don't lint prelude glob imports
-            if !use_path.segments.iter().last().map_or(false, |ps| ps.ident.as_str() == "prelude");
+            if !is_prelude_import(use_path.segments);
+            if !is_super_only_import_in_test(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 {
@@ -154,3 +154,16 @@ impl LateLintPass<'_, '_> for 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().last().map_or(false, |ps| ps.ident.as_str() == "prelude")
+}
+
+// Allow "super::*" imports.
+// This is intended primarily to ease the process of writing unit tests.
+fn is_super_only_import_in_test(segments: &[PathSegment<'_>]) -> bool {
+    segments.iter().len() == 1 &&
+        segments.first().map_or(false, |ps| ps.ident.as_str() == "super")
+}
diff --git a/tests/ui/wildcard_imports.fixed b/tests/ui/wildcard_imports.fixed
index ed6cc00ef048..003f11009a06 100644
--- a/tests/ui/wildcard_imports.fixed
+++ b/tests/ui/wildcard_imports.fixed
@@ -155,3 +155,41 @@ fn test_weird_formatting() {
     exported();
     foo();
 }
+
+mod test_super_imports {
+    fn foofoo() {}
+
+    mod use_super {
+        use super::*;
+
+        fn with_super() {
+            let _ = foofoo();
+        }
+    }
+
+    mod use_explicit {
+        use test_super_imports::foofoo;
+
+        fn with_explicit() {
+            let _ = foofoo();
+        }
+    }
+
+    mod use_double_super {
+        mod inner {
+            use super::super::foofoo;
+
+            fn with_double_super() {
+                let _ = foofoo();
+            }
+        }
+    }
+
+    mod use_super_explicit {
+        use super::super::test_super_imports::foofoo;
+
+        fn with_super_explicit() {
+            let _ = foofoo();
+        }
+    }
+}
diff --git a/tests/ui/wildcard_imports.rs b/tests/ui/wildcard_imports.rs
index c6d6efaece81..7bd57c7965a6 100644
--- a/tests/ui/wildcard_imports.rs
+++ b/tests/ui/wildcard_imports.rs
@@ -156,3 +156,41 @@ fn test_weird_formatting() {
     exported();
     foo();
 }
+
+mod test_super_imports {
+    fn foofoo() {}
+
+    mod use_super {
+        use super::*;
+
+        fn with_super() {
+            let _ = foofoo();
+        }
+    }
+
+    mod use_explicit {
+        use test_super_imports::*;
+
+        fn with_explicit() {
+            let _ = foofoo();
+        }
+    }
+
+    mod use_double_super {
+        mod inner {
+            use super::super::*;
+
+            fn with_double_super() {
+                let _ = foofoo();
+            }
+        }
+    }
+
+    mod use_super_explicit {
+        use super::super::test_super_imports::*;
+
+        fn with_super_explicit() {
+            let _ = foofoo();
+        }
+    }
+}
diff --git a/tests/ui/wildcard_imports.stderr b/tests/ui/wildcard_imports.stderr
index 050e4c6304f0..858dc28797fa 100644
--- a/tests/ui/wildcard_imports.stderr
+++ b/tests/ui/wildcard_imports.stderr
@@ -92,5 +92,23 @@ LL |       use crate:: fn_mod::
 LL | |         *;
    | |_________^ help: try: `crate:: fn_mod::foo`
 
-error: aborting due to 15 previous errors
+error: usage of wildcard import
+  --> $DIR/wildcard_imports.rs:172:13
+   |
+LL |         use test_super_imports::*;
+   |             ^^^^^^^^^^^^^^^^^^^^^ help: try: `test_super_imports::foofoo`
+
+error: usage of wildcard import
+  --> $DIR/wildcard_imports.rs:181:17
+   |
+LL |             use super::super::*;
+   |                 ^^^^^^^^^^^^^^^ help: try: `super::super::foofoo`
+
+error: usage of wildcard import
+  --> $DIR/wildcard_imports.rs:190:13
+   |
+LL |         use super::super::test_super_imports::*;
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `super::super::test_super_imports::foofoo`
+
+error: aborting due to 18 previous errors
 

From bdc75dbb7bbdc379b1f8cc346151fac4e63d7deb Mon Sep 17 00:00:00 2001
From: Glenn Hope <glenn.alexander.hope@gmail.com>
Date: Sun, 3 May 2020 11:18:10 -0700
Subject: [PATCH 02/10] Run `cargo dev fmt`

---
 clippy_lints/src/wildcard_imports.rs | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/clippy_lints/src/wildcard_imports.rs b/clippy_lints/src/wildcard_imports.rs
index 70ad9a60a02c..e7400642b078 100644
--- a/clippy_lints/src/wildcard_imports.rs
+++ b/clippy_lints/src/wildcard_imports.rs
@@ -158,12 +158,14 @@ impl LateLintPass<'_, '_> for 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().last().map_or(false, |ps| ps.ident.as_str() == "prelude")
+    segments
+        .iter()
+        .last()
+        .map_or(false, |ps| ps.ident.as_str() == "prelude")
 }
 
 // Allow "super::*" imports.
 // This is intended primarily to ease the process of writing unit tests.
 fn is_super_only_import_in_test(segments: &[PathSegment<'_>]) -> bool {
-    segments.iter().len() == 1 &&
-        segments.first().map_or(false, |ps| ps.ident.as_str() == "super")
+    segments.iter().len() == 1 && segments.first().map_or(false, |ps| ps.ident.as_str() == "super")
 }

From 56f4e1c3a8be54c1c80de366618e83d8d7a6e9eb Mon Sep 17 00:00:00 2001
From: Glenn Hope <glenn.alexander.hope@gmail.com>
Date: Thu, 7 May 2020 08:06:30 -0700
Subject: [PATCH 03/10] Check if the parent module name contains "test"

---
 clippy_lints/src/wildcard_imports.rs | 19 ++++++++++++-------
 tests/ui/wildcard_imports.fixed      | 16 ++++++++++++----
 tests/ui/wildcard_imports.rs         | 16 ++++++++++++----
 tests/ui/wildcard_imports.stderr     | 14 ++++++++++----
 4 files changed, 46 insertions(+), 19 deletions(-)

diff --git a/clippy_lints/src/wildcard_imports.rs b/clippy_lints/src/wildcard_imports.rs
index e7400642b078..a22d0e6775de 100644
--- a/clippy_lints/src/wildcard_imports.rs
+++ b/clippy_lints/src/wildcard_imports.rs
@@ -84,7 +84,7 @@ impl LateLintPass<'_, '_> for WildcardImports {
             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_in_test(use_path.segments);
+            if !(is_super_only_import(use_path.segments) && is_in_test_module(cx, item));
             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 {
@@ -109,8 +109,7 @@ impl LateLintPass<'_, '_> for WildcardImports {
                         span = use_path.span.with_hi(item.span.hi() - BytePos(1));
                     }
                     (
-                        span,
-                        false,
+                        span, false,
                     )
                 };
 
@@ -164,8 +163,14 @@ fn is_prelude_import(segments: &[PathSegment<'_>]) -> bool {
         .map_or(false, |ps| ps.ident.as_str() == "prelude")
 }
 
-// Allow "super::*" imports.
-// This is intended primarily to ease the process of writing unit tests.
-fn is_super_only_import_in_test(segments: &[PathSegment<'_>]) -> bool {
-    segments.iter().len() == 1 && segments.first().map_or(false, |ps| ps.ident.as_str() == "super")
+// Allow "super::*" imports in tests.
+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")
 }
diff --git a/tests/ui/wildcard_imports.fixed b/tests/ui/wildcard_imports.fixed
index 003f11009a06..1c5c01f65d15 100644
--- a/tests/ui/wildcard_imports.fixed
+++ b/tests/ui/wildcard_imports.fixed
@@ -159,7 +159,15 @@ fn test_weird_formatting() {
 mod test_super_imports {
     fn foofoo() {}
 
-    mod use_super {
+    mod use_super_should_be_replaced {
+        use super::foofoo;
+
+        fn with_super() {
+            let _ = foofoo();
+        }
+    }
+
+    mod use_super_in_test_should_pass {
         use super::*;
 
         fn with_super() {
@@ -167,7 +175,7 @@ mod test_super_imports {
         }
     }
 
-    mod use_explicit {
+    mod use_explicit_should_be_replaced {
         use test_super_imports::foofoo;
 
         fn with_explicit() {
@@ -175,7 +183,7 @@ mod test_super_imports {
         }
     }
 
-    mod use_double_super {
+    mod use_double_super_should_be_replaced {
         mod inner {
             use super::super::foofoo;
 
@@ -185,7 +193,7 @@ mod test_super_imports {
         }
     }
 
-    mod use_super_explicit {
+    mod use_super_explicit_should_be_replaced {
         use super::super::test_super_imports::foofoo;
 
         fn with_super_explicit() {
diff --git a/tests/ui/wildcard_imports.rs b/tests/ui/wildcard_imports.rs
index 7bd57c7965a6..f783149ef93e 100644
--- a/tests/ui/wildcard_imports.rs
+++ b/tests/ui/wildcard_imports.rs
@@ -160,7 +160,7 @@ fn test_weird_formatting() {
 mod test_super_imports {
     fn foofoo() {}
 
-    mod use_super {
+    mod use_super_should_be_replaced {
         use super::*;
 
         fn with_super() {
@@ -168,7 +168,15 @@ mod test_super_imports {
         }
     }
 
-    mod use_explicit {
+    mod use_super_in_test_should_pass {
+        use super::*;
+
+        fn with_super() {
+            let _ = foofoo();
+        }
+    }
+
+    mod use_explicit_should_be_replaced {
         use test_super_imports::*;
 
         fn with_explicit() {
@@ -176,7 +184,7 @@ mod test_super_imports {
         }
     }
 
-    mod use_double_super {
+    mod use_double_super_should_be_replaced {
         mod inner {
             use super::super::*;
 
@@ -186,7 +194,7 @@ mod test_super_imports {
         }
     }
 
-    mod use_super_explicit {
+    mod use_super_explicit_should_be_replaced {
         use super::super::test_super_imports::*;
 
         fn with_super_explicit() {
diff --git a/tests/ui/wildcard_imports.stderr b/tests/ui/wildcard_imports.stderr
index 858dc28797fa..649d550a88d1 100644
--- a/tests/ui/wildcard_imports.stderr
+++ b/tests/ui/wildcard_imports.stderr
@@ -93,22 +93,28 @@ LL | |         *;
    | |_________^ help: try: `crate:: fn_mod::foo`
 
 error: usage of wildcard import
-  --> $DIR/wildcard_imports.rs:172:13
+  --> $DIR/wildcard_imports.rs:164:13
+   |
+LL |         use super::*;
+   |             ^^^^^^^^ help: try: `super::foofoo`
+
+error: usage of wildcard import
+  --> $DIR/wildcard_imports.rs:180:13
    |
 LL |         use test_super_imports::*;
    |             ^^^^^^^^^^^^^^^^^^^^^ help: try: `test_super_imports::foofoo`
 
 error: usage of wildcard import
-  --> $DIR/wildcard_imports.rs:181:17
+  --> $DIR/wildcard_imports.rs:189:17
    |
 LL |             use super::super::*;
    |                 ^^^^^^^^^^^^^^^ help: try: `super::super::foofoo`
 
 error: usage of wildcard import
-  --> $DIR/wildcard_imports.rs:190:13
+  --> $DIR/wildcard_imports.rs:198:13
    |
 LL |         use super::super::test_super_imports::*;
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `super::super::test_super_imports::foofoo`
 
-error: aborting due to 18 previous errors
+error: aborting due to 19 previous errors
 

From ad92486d52fdede5c712dd27c868c942d8240704 Mon Sep 17 00:00:00 2001
From: Glenn Hope <glenn.alexander.hope@gmail.com>
Date: Thu, 7 May 2020 14:41:54 -0700
Subject: [PATCH 04/10] Add check for "test" in parent name. Include flag for
 disabling wildcard import exceptions

---
 clippy_lints/src/lib.rs                       |  3 +-
 clippy_lints/src/utils/conf.rs                |  2 +
 clippy_lints/src/wildcard_imports.rs          | 48 +++++++++++++++----
 .../toml_unknown_key/conf_unknown_key.stderr  |  2 +-
 tests/ui/wildcard_imports.fixed               | 17 +++++--
 tests/ui/wildcard_imports.rs                  | 17 +++++--
 tests/ui/wildcard_imports.stderr              | 14 +++---
 7 files changed, 75 insertions(+), 28 deletions(-)

diff --git a/clippy_lints/src/lib.rs b/clippy_lints/src/lib.rs
index fb2e9932b8e4..4b67c84e38ed 100644
--- a/clippy_lints/src/lib.rs
+++ b/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());
diff --git a/clippy_lints/src/utils/conf.rs b/clippy_lints/src/utils/conf.rs
index 4b81ff33495c..57b9eafd14db 100644
--- a/clippy_lints/src/utils/conf.rs
+++ b/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 {
diff --git a/clippy_lints/src/wildcard_imports.rs b/clippy_lints/src/wildcard_imports.rs
index a22d0e6775de..43d0d1b9e96c 100644
--- a/clippy_lints/src/wildcard_imports.rs
+++ b/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")
 }
diff --git a/tests/ui-toml/toml_unknown_key/conf_unknown_key.stderr b/tests/ui-toml/toml_unknown_key/conf_unknown_key.stderr
index 18f5d994ba8a..53970af41079 100644
--- a/tests/ui-toml/toml_unknown_key/conf_unknown_key.stderr
+++ b/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
 
diff --git a/tests/ui/wildcard_imports.fixed b/tests/ui/wildcard_imports.fixed
index 1c5c01f65d15..98bf6acfe55f 100644
--- a/tests/ui/wildcard_imports.fixed
+++ b/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();
diff --git a/tests/ui/wildcard_imports.rs b/tests/ui/wildcard_imports.rs
index f783149ef93e..9275c5a09286 100644
--- a/tests/ui/wildcard_imports.rs
+++ b/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();
diff --git a/tests/ui/wildcard_imports.stderr b/tests/ui/wildcard_imports.stderr
index 649d550a88d1..bd000ce81616 100644
--- a/tests/ui/wildcard_imports.stderr
+++ b/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
 

From a42a2bdac2a6c881f85ebdbce66e84d977c74cfa Mon Sep 17 00:00:00 2001
From: Glenn Hope <glenn.alexander.hope@gmail.com>
Date: Thu, 7 May 2020 14:48:27 -0700
Subject: [PATCH 05/10] Also have flag disable macro check

---
 clippy_lints/src/wildcard_imports.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/clippy_lints/src/wildcard_imports.rs b/clippy_lints/src/wildcard_imports.rs
index 43d0d1b9e96c..843ddda03569 100644
--- a/clippy_lints/src/wildcard_imports.rs
+++ b/clippy_lints/src/wildcard_imports.rs
@@ -102,7 +102,7 @@ impl LateLintPass<'_, '_> for WildcardImports {
             self.test_modules_deep += 1;
         }
         if_chain! {
-            if !in_macro(item.span);
+            if self.warn_on_all || !in_macro(item.span);
             if let ItemKind::Use(use_path, UseKind::Glob) = &item.kind;
             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);

From 152cdcb45be7a8f0f24dbcd4177e0858d94516b6 Mon Sep 17 00:00:00 2001
From: Glenn Hope <glenn.alexander.hope@gmail.com>
Date: Fri, 8 May 2020 18:22:27 -0700
Subject: [PATCH 06/10] Remove unnecessary field, check for Mod/Fn ItemKind

---
 clippy_lints/src/wildcard_imports.rs | 14 +++++---------
 1 file changed, 5 insertions(+), 9 deletions(-)

diff --git a/clippy_lints/src/wildcard_imports.rs b/clippy_lints/src/wildcard_imports.rs
index 843ddda03569..48405a00d554 100644
--- a/clippy_lints/src/wildcard_imports.rs
+++ b/clippy_lints/src/wildcard_imports.rs
@@ -76,7 +76,6 @@ declare_clippy_lint! {
 #[derive(Default)]
 pub struct WildcardImports {
     warn_on_all: bool,
-    is_test_module: bool,
     test_modules_deep: u32,
 }
 
@@ -84,7 +83,6 @@ impl WildcardImports {
     pub fn new(warn_on_all: bool) -> Self {
         Self {
             warn_on_all,
-            is_test_module: false,
             test_modules_deep: 0,
         }
     }
@@ -97,8 +95,7 @@ impl LateLintPass<'_, '_> for WildcardImports {
         if item.vis.node.is_pub() || item.vis.node.is_pub_restricted() {
             return;
         }
-        if is_test_module(item) {
-            self.is_test_module = true;
+        if is_test_module_or_function(item) {
             self.test_modules_deep += 1;
         }
         if_chain! {
@@ -173,9 +170,8 @@ impl LateLintPass<'_, '_> for WildcardImports {
         }
     }
 
-    fn check_item_post(&mut self, _: &LateContext<'_, '_>, _: &Item<'_>) {
-        if self.is_test_module {
-            self.is_test_module = false;
+    fn check_item_post(&mut self, _: &LateContext<'_, '_>, item: &Item<'_>) {
+        if is_test_module_or_function(item) {
             self.test_modules_deep -= 1;
         }
     }
@@ -201,6 +197,6 @@ fn is_super_only_import(segments: &[PathSegment<'_>]) -> bool {
     segments.len() == 1 && segments[0].ident.as_str() == "super"
 }
 
-fn is_test_module(item: &Item<'_>) -> bool {
-    item.ident.name.as_str().contains("test")
+fn is_test_module_or_function(item: &Item<'_>) -> bool {
+    matches!(item.kind, ItemKind::Fn(..) | ItemKind::Mod(..)) && item.ident.name.as_str().contains("test")
 }

From 4db6abcd50eb07a7fa8349a059f80792b7b19a2e Mon Sep 17 00:00:00 2001
From: Glenn Hope <glenn.alexander.hope@gmail.com>
Date: Sat, 9 May 2020 08:04:07 -0700
Subject: [PATCH 07/10] Remove check for Fn, reflect this in test cases, make
 test cases more robust/explicit

---
 clippy_lints/src/wildcard_imports.rs | 13 +++++++++----
 tests/ui/wildcard_imports.fixed      | 25 +++++++++++++++++++++++--
 tests/ui/wildcard_imports.rs         | 24 ++++++++++++++++++++++--
 tests/ui/wildcard_imports.stderr     | 14 ++++++++++----
 4 files changed, 64 insertions(+), 12 deletions(-)

diff --git a/clippy_lints/src/wildcard_imports.rs b/clippy_lints/src/wildcard_imports.rs
index 48405a00d554..e12a6659ab5b 100644
--- a/clippy_lints/src/wildcard_imports.rs
+++ b/clippy_lints/src/wildcard_imports.rs
@@ -43,9 +43,14 @@ declare_clippy_lint! {
     ///
     /// This can lead to confusing error messages at best and to unexpected behavior at worst.
     ///
-    /// Note that this will not warn about wildcard imports from modules named `prelude`; many
-    /// crates (including the standard library) provide modules named "prelude" specifically
-    /// designed for wildcard import.
+    /// **Exceptions:**
+    ///
+    /// Wildcard imports are allowed from modules named `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.
+    ///
+    /// These exceptions can be disabled using the `warn-on-all-wildcard-imports` configuration flag.
     ///
     /// **Known problems:** If macros are imported through the wildcard, this macro is not included
     /// by the suggestion and has to be added by hand.
@@ -198,5 +203,5 @@ fn is_super_only_import(segments: &[PathSegment<'_>]) -> bool {
 }
 
 fn is_test_module_or_function(item: &Item<'_>) -> bool {
-    matches!(item.kind, ItemKind::Fn(..) | ItemKind::Mod(..)) && item.ident.name.as_str().contains("test")
+    matches!(item.kind, ItemKind::Mod(..)) && item.ident.name.as_str().contains("test")
 }
diff --git a/tests/ui/wildcard_imports.fixed b/tests/ui/wildcard_imports.fixed
index 98bf6acfe55f..b47c8f23e240 100644
--- a/tests/ui/wildcard_imports.fixed
+++ b/tests/ui/wildcard_imports.fixed
@@ -175,13 +175,34 @@ mod super_imports {
         }
     }
 
-    mod inner {
-        fn test_should_pass() {
+    mod test_should_pass_inside_function {
+        fn with_super_inside_function() {
             use super::*;
             let _ = foofoo();
         }
     }
 
+    mod test_should_pass_further_inside {
+        fn insidefoo() {}
+        mod inner {
+            use super::*;
+            fn with_super() {
+                let _ = insidefoo();
+            }
+        }
+    }
+
+    mod should_be_replaced_futher_inside {
+        fn insidefoo() {}
+        mod inner {
+            use super::insidefoo;
+            fn with_super() {
+                let _ = insidefoo();
+            }
+        }
+    }
+
+
     mod use_explicit_should_be_replaced {
         use super_imports::foofoo;
 
diff --git a/tests/ui/wildcard_imports.rs b/tests/ui/wildcard_imports.rs
index 9275c5a09286..3ad1a29aebad 100644
--- a/tests/ui/wildcard_imports.rs
+++ b/tests/ui/wildcard_imports.rs
@@ -176,13 +176,33 @@ mod super_imports {
         }
     }
 
-    mod inner {
-        fn test_should_pass() {
+    mod test_should_pass_inside_function {
+        fn with_super_inside_function() {
             use super::*;
             let _ = foofoo();
         }
     }
 
+    mod test_should_pass_further_inside {
+        fn insidefoo() {}
+        mod inner {
+            use super::*;
+            fn with_super() {
+                let _ = insidefoo();
+            }
+        }
+    }
+
+    mod should_be_replaced_futher_inside {
+        fn insidefoo() {}
+        mod inner {
+            use super::*;
+            fn with_super() {
+                let _ = insidefoo();
+            }
+        }
+    }
+
     mod use_explicit_should_be_replaced {
         use super_imports::*;
 
diff --git a/tests/ui/wildcard_imports.stderr b/tests/ui/wildcard_imports.stderr
index bd000ce81616..de07bd1d69ba 100644
--- a/tests/ui/wildcard_imports.stderr
+++ b/tests/ui/wildcard_imports.stderr
@@ -99,22 +99,28 @@ LL |         use super::*;
    |             ^^^^^^^^ help: try: `super::foofoo`
 
 error: usage of wildcard import
-  --> $DIR/wildcard_imports.rs:187:13
+  --> $DIR/wildcard_imports.rs:199:17
+   |
+LL |             use super::*;
+   |                 ^^^^^^^^ help: try: `super::insidefoo`
+
+error: usage of wildcard import
+  --> $DIR/wildcard_imports.rs:208:13
    |
 LL |         use super_imports::*;
    |             ^^^^^^^^^^^^^^^^ help: try: `super_imports::foofoo`
 
 error: usage of wildcard import
-  --> $DIR/wildcard_imports.rs:196:17
+  --> $DIR/wildcard_imports.rs:217:17
    |
 LL |             use super::super::*;
    |                 ^^^^^^^^^^^^^^^ help: try: `super::super::foofoo`
 
 error: usage of wildcard import
-  --> $DIR/wildcard_imports.rs:205:13
+  --> $DIR/wildcard_imports.rs:226:13
    |
 LL |         use super::super::super_imports::*;
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `super::super::super_imports::foofoo`
 
-error: aborting due to 19 previous errors
+error: aborting due to 20 previous errors
 

From a339766136a183327faaf13b987be30b2940872e Mon Sep 17 00:00:00 2001
From: Glenn Hope <glenn.alexander.hope@gmail.com>
Date: Sat, 9 May 2020 08:33:35 -0700
Subject: [PATCH 08/10] Fix test from auto-formatter fix

---
 tests/ui/wildcard_imports.fixed | 1 -
 1 file changed, 1 deletion(-)

diff --git a/tests/ui/wildcard_imports.fixed b/tests/ui/wildcard_imports.fixed
index b47c8f23e240..67423e6ec1d1 100644
--- a/tests/ui/wildcard_imports.fixed
+++ b/tests/ui/wildcard_imports.fixed
@@ -202,7 +202,6 @@ mod super_imports {
         }
     }
 
-
     mod use_explicit_should_be_replaced {
         use super_imports::foofoo;
 

From 0ba61c612ee873314d252ca1f747c14a2f0161ba Mon Sep 17 00:00:00 2001
From: Glenn Hope <glenn.alexander.hope@gmail.com>
Date: Sat, 9 May 2020 10:14:29 -0700
Subject: [PATCH 09/10] Check is_macro inside check_exceptions, update
 references to fix test

---
 clippy_lints/src/wildcard_imports.rs | 13 +++++++------
 tests/ui/wildcard_imports.stderr     |  6 +++---
 2 files changed, 10 insertions(+), 9 deletions(-)

diff --git a/clippy_lints/src/wildcard_imports.rs b/clippy_lints/src/wildcard_imports.rs
index e12a6659ab5b..2c4e24780e7d 100644
--- a/clippy_lints/src/wildcard_imports.rs
+++ b/clippy_lints/src/wildcard_imports.rs
@@ -101,12 +101,11 @@ impl LateLintPass<'_, '_> for WildcardImports {
             return;
         }
         if is_test_module_or_function(item) {
-            self.test_modules_deep += 1;
+            self.test_modules_deep = self.test_modules_deep.saturating_add(1);
         }
         if_chain! {
-            if self.warn_on_all || !in_macro(item.span);
             if let ItemKind::Use(use_path, UseKind::Glob) = &item.kind;
-            if self.warn_on_all || !self.check_exceptions(use_path.segments);
+            if self.warn_on_all || !self.check_exceptions(item, 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 {
@@ -177,14 +176,16 @@ impl LateLintPass<'_, '_> for WildcardImports {
 
     fn check_item_post(&mut self, _: &LateContext<'_, '_>, item: &Item<'_>) {
         if is_test_module_or_function(item) {
-            self.test_modules_deep -= 1;
+            self.test_modules_deep = self.test_modules_deep.saturating_sub(1);
         }
     }
 }
 
 impl WildcardImports {
-    fn check_exceptions(&self, segments: &[PathSegment<'_>]) -> bool {
-        is_prelude_import(segments) || (is_super_only_import(segments) && self.test_modules_deep > 0)
+    fn check_exceptions(&self, item: &Item<'_>, segments: &[PathSegment<'_>]) -> bool {
+        in_macro(item.span)
+            || is_prelude_import(segments)
+            || (is_super_only_import(segments) && self.test_modules_deep > 0)
     }
 }
 
diff --git a/tests/ui/wildcard_imports.stderr b/tests/ui/wildcard_imports.stderr
index de07bd1d69ba..fab43b738eb4 100644
--- a/tests/ui/wildcard_imports.stderr
+++ b/tests/ui/wildcard_imports.stderr
@@ -105,19 +105,19 @@ LL |             use super::*;
    |                 ^^^^^^^^ help: try: `super::insidefoo`
 
 error: usage of wildcard import
-  --> $DIR/wildcard_imports.rs:208:13
+  --> $DIR/wildcard_imports.rs:207:13
    |
 LL |         use super_imports::*;
    |             ^^^^^^^^^^^^^^^^ help: try: `super_imports::foofoo`
 
 error: usage of wildcard import
-  --> $DIR/wildcard_imports.rs:217:17
+  --> $DIR/wildcard_imports.rs:216:17
    |
 LL |             use super::super::*;
    |                 ^^^^^^^^^^^^^^^ help: try: `super::super::foofoo`
 
 error: usage of wildcard import
-  --> $DIR/wildcard_imports.rs:226:13
+  --> $DIR/wildcard_imports.rs:225:13
    |
 LL |         use super::super::super_imports::*;
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `super::super::super_imports::foofoo`

From b69200b8468434bc3f5b9ef8468733e5d40f4e01 Mon Sep 17 00:00:00 2001
From: Glenn Hope <glenn.alexander.hope@gmail.com>
Date: Sat, 9 May 2020 10:16:47 -0700
Subject: [PATCH 10/10] Move is_test_module check to top of function

---
 clippy_lints/src/wildcard_imports.rs | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/clippy_lints/src/wildcard_imports.rs b/clippy_lints/src/wildcard_imports.rs
index 2c4e24780e7d..32d9a45c37d7 100644
--- a/clippy_lints/src/wildcard_imports.rs
+++ b/clippy_lints/src/wildcard_imports.rs
@@ -97,12 +97,12 @@ 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_or_function(item) {
             self.test_modules_deep = self.test_modules_deep.saturating_add(1);
         }
+        if item.vis.node.is_pub() || item.vis.node.is_pub_restricted() {
+            return;
+        }
         if_chain! {
             if let ItemKind::Use(use_path, UseKind::Glob) = &item.kind;
             if self.warn_on_all || !self.check_exceptions(item, use_path.segments);