3 files changed, 33 insertions, 1 deletions
diff --git a/tests/ui/manual_is_ascii_check.fixed b/tests/ui/manual_is_ascii_check.fixed
index a72caa3a37e..179149f697d 100644
--- a/tests/ui/manual_is_ascii_check.fixed
+++ b/tests/ui/manual_is_ascii_check.fixed
@@ -82,3 +82,8 @@ fn generics() {
     take_while(|c: u8| c.is_ascii_uppercase());
     take_while(|c: char| c.is_ascii_uppercase());
 }
+
+fn adds_type_reference() {
+    let digits: Vec<&char> = ['1', 'A'].iter().take_while(|c: &&char| c.is_ascii_digit()).collect();
+    let digits: Vec<&mut char> = ['1', 'A'].iter_mut().take_while(|c: &&mut char| c.is_ascii_digit()).collect();
+}
diff --git a/tests/ui/manual_is_ascii_check.rs b/tests/ui/manual_is_ascii_check.rs
index bb6e2a317da..74f35ce94e8 100644
--- a/tests/ui/manual_is_ascii_check.rs
+++ b/tests/ui/manual_is_ascii_check.rs
@@ -82,3 +82,8 @@ fn generics() {
     take_while(|c| (b'A'..=b'Z').contains(&c));
     take_while(|c: char| ('A'..='Z').contains(&c));
 }
+
+fn adds_type_reference() {
+    let digits: Vec<&char> = ['1', 'A'].iter().take_while(|c| ('0'..='9').contains(c)).collect();
+    let digits: Vec<&mut char> = ['1', 'A'].iter_mut().take_while(|c| ('0'..='9').contains(c)).collect();
+}
diff --git a/tests/ui/manual_is_ascii_check.stderr b/tests/ui/manual_is_ascii_check.stderr
index a93ccace28a..92d93208006 100644
--- a/tests/ui/manual_is_ascii_check.stderr
+++ b/tests/ui/manual_is_ascii_check.stderr
@@ -173,5 +173,27 @@ error: manual check for common ascii range
 LL |     take_while(|c: char| ('A'..='Z').contains(&c));
    |                          ^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `c.is_ascii_uppercase()`
 
-error: aborting due to 27 previous errors
+error: manual check for common ascii range
+  --> tests/ui/manual_is_ascii_check.rs:87:63
+   |
+LL |     let digits: Vec<&char> = ['1', 'A'].iter().take_while(|c| ('0'..='9').contains(c)).collect();
+   |                                                               ^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: try
+   |
+LL |     let digits: Vec<&char> = ['1', 'A'].iter().take_while(|c: &&char| c.is_ascii_digit()).collect();
+   |                                                            ~~~~~~~~~  ~~~~~~~~~~~~~~~~~~
+
+error: manual check for common ascii range
+  --> tests/ui/manual_is_ascii_check.rs:88:71
+   |
+LL |     let digits: Vec<&mut char> = ['1', 'A'].iter_mut().take_while(|c| ('0'..='9').contains(c)).collect();
+   |                                                                       ^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: try
+   |
+LL |     let digits: Vec<&mut char> = ['1', 'A'].iter_mut().take_while(|c: &&mut char| c.is_ascii_digit()).collect();
+   |                                                                    ~~~~~~~~~~~~~  ~~~~~~~~~~~~~~~~~~
+
+error: aborting due to 29 previous errors