Auto merge of #10053 - naosense:fix_9933, r=xFrednet

improve `manual_is_ascii_check ` check

Sorry, not familiar the api, i can only check the method name of expression `<expr-1>.contains(<expr-2>)` after read clippy book and hints from #9933 . i dont know how to check
1.  if <expr-1> is a specific range
2. <expr-2> is a character

r? `@xFrednet` could you please provide some more hints? 😝️

---

changelog: Enhancement: [`manual_is_ascii_check`]: Now detects ranges with `.contains()` calls
[#10053](https://github.com/rust-lang/rust-clippy/pull/10053)
<!-- changelog_checked -->

3 files changed, 85 insertions, 5 deletions

diff --git a/tests/ui/manual_is_ascii_check.fixed b/tests/ui/manual_is_ascii_check.fixed
index 231ba83b142..5b2b44c2fdb 100644
--- a/tests/ui/manual_is_ascii_check.fixed
+++ b/tests/ui/manual_is_ascii_check.fixed
@@ -15,6 +15,19 @@ fn main() {
     assert!('x'.is_ascii_alphabetic());
 
     assert!(matches!('x', 'A'..='Z' | 'a'..='z' | '_'));
+
+    b'0'.is_ascii_digit();
+    b'a'.is_ascii_lowercase();
+    b'A'.is_ascii_uppercase();
+
+    '0'.is_ascii_digit();
+    'a'.is_ascii_lowercase();
+    'A'.is_ascii_uppercase();
+
+    let cool_letter = &'g';
+    cool_letter.is_ascii_digit();
+    cool_letter.is_ascii_lowercase();
+    cool_letter.is_ascii_uppercase();
 }
 
 #[clippy::msrv = "1.23"]
diff --git a/tests/ui/manual_is_ascii_check.rs b/tests/ui/manual_is_ascii_check.rs
index 39ee6151c56..c9433f33a1b 100644
--- a/tests/ui/manual_is_ascii_check.rs
+++ b/tests/ui/manual_is_ascii_check.rs
@@ -15,6 +15,19 @@ fn main() {
     assert!(matches!('x', 'A'..='Z' | 'a'..='z'));
 
     assert!(matches!('x', 'A'..='Z' | 'a'..='z' | '_'));
+
+    (b'0'..=b'9').contains(&b'0');
+    (b'a'..=b'z').contains(&b'a');
+    (b'A'..=b'Z').contains(&b'A');
+
+    ('0'..='9').contains(&'0');
+    ('a'..='z').contains(&'a');
+    ('A'..='Z').contains(&'A');
+
+    let cool_letter = &'g';
+    ('0'..='9').contains(cool_letter);
+    ('a'..='z').contains(cool_letter);
+    ('A'..='Z').contains(cool_letter);
 }
 
 #[clippy::msrv = "1.23"]
diff --git a/tests/ui/manual_is_ascii_check.stderr b/tests/ui/manual_is_ascii_check.stderr
index 397cbe05c82..ee60188506d 100644
--- a/tests/ui/manual_is_ascii_check.stderr
+++ b/tests/ui/manual_is_ascii_check.stderr
@@ -43,28 +43,82 @@ LL |     assert!(matches!('x', 'A'..='Z' | 'a'..='z'));
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `'x'.is_ascii_alphabetic()`
 
 error: manual check for common ascii range
-  --> $DIR/manual_is_ascii_check.rs:29:13
+  --> $DIR/manual_is_ascii_check.rs:19:5
+   |
+LL |     (b'0'..=b'9').contains(&b'0');
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `b'0'.is_ascii_digit()`
+
+error: manual check for common ascii range
+  --> $DIR/manual_is_ascii_check.rs:20:5
+   |
+LL |     (b'a'..=b'z').contains(&b'a');
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `b'a'.is_ascii_lowercase()`
+
+error: manual check for common ascii range
+  --> $DIR/manual_is_ascii_check.rs:21:5
+   |
+LL |     (b'A'..=b'Z').contains(&b'A');
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `b'A'.is_ascii_uppercase()`
+
+error: manual check for common ascii range
+  --> $DIR/manual_is_ascii_check.rs:23:5
+   |
+LL |     ('0'..='9').contains(&'0');
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `'0'.is_ascii_digit()`
+
+error: manual check for common ascii range
+  --> $DIR/manual_is_ascii_check.rs:24:5
+   |
+LL |     ('a'..='z').contains(&'a');
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `'a'.is_ascii_lowercase()`
+
+error: manual check for common ascii range
+  --> $DIR/manual_is_ascii_check.rs:25:5
+   |
+LL |     ('A'..='Z').contains(&'A');
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `'A'.is_ascii_uppercase()`
+
+error: manual check for common ascii range
+  --> $DIR/manual_is_ascii_check.rs:28:5
+   |
+LL |     ('0'..='9').contains(cool_letter);
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `cool_letter.is_ascii_digit()`
+
+error: manual check for common ascii range
+  --> $DIR/manual_is_ascii_check.rs:29:5
+   |
+LL |     ('a'..='z').contains(cool_letter);
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `cool_letter.is_ascii_lowercase()`
+
+error: manual check for common ascii range
+  --> $DIR/manual_is_ascii_check.rs:30:5
+   |
+LL |     ('A'..='Z').contains(cool_letter);
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `cool_letter.is_ascii_uppercase()`
+
+error: manual check for common ascii range
+  --> $DIR/manual_is_ascii_check.rs:42:13
    |
 LL |     assert!(matches!(b'1', b'0'..=b'9'));
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `b'1'.is_ascii_digit()`
 
 error: manual check for common ascii range
-  --> $DIR/manual_is_ascii_check.rs:30:13
+  --> $DIR/manual_is_ascii_check.rs:43:13
    |
 LL |     assert!(matches!('X', 'A'..='Z'));
    |             ^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `'X'.is_ascii_uppercase()`
 
 error: manual check for common ascii range
-  --> $DIR/manual_is_ascii_check.rs:31:13
+  --> $DIR/manual_is_ascii_check.rs:44:13
    |
 LL |     assert!(matches!('x', 'A'..='Z' | 'a'..='z'));
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `'x'.is_ascii_alphabetic()`
 
 error: manual check for common ascii range
-  --> $DIR/manual_is_ascii_check.rs:41:23
+  --> $DIR/manual_is_ascii_check.rs:54:23
    |
 LL |     const FOO: bool = matches!('x', '0'..='9');
    |                       ^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `'x'.is_ascii_digit()`
 
-error: aborting due to 11 previous errors
+error: aborting due to 20 previous errors