refactor: Hard-code char::is_control

According to
https://www.unicode.org/policies/stability_policy.html#Property_Value,
the set of codepoints in `Cc` will never change. So we can hard-code
the patterns to match against instead of using a table.

Author: Kmeakin

library/core/src/char/methods.rs

@@ -950,7 +950,11 @@ impl char {
     #[stable(feature = "rust1", since = "1.0.0")]
     #[inline]
     pub fn is_control(self) -> bool {
-        if self.is_ascii() { self.is_ascii_control() } else { unicode::Cc(self) }
+        // According to
+        // https://www.unicode.org/policies/stability_policy.html#Property_Value,
+        // the set of codepoints in `Cc` will never change. So we can hard-code
+        // the patterns to match against instead of using a table.
+        matches!(self, '\0'..='\x1f' | '\x7f'..='\u{9f}')
     }
 
     /// Returns `true` if this `char` has the `Grapheme_Extend` property.

library/core/src/unicode/mod.rs

@@ -8,7 +8,6 @@ pub use unicode_data::conversions;
 #[rustfmt::skip]
 pub(crate) use unicode_data::alphabetic::lookup as Alphabetic;
 pub(crate) use unicode_data::case_ignorable::lookup as Case_Ignorable;
-pub(crate) use unicode_data::cc::lookup as Cc;
 pub(crate) use unicode_data::grapheme_extend::lookup as Grapheme_Extend;
 pub(crate) use unicode_data::lowercase::lookup as Lowercase;
 pub(crate) use unicode_data::lt::lookup as Lt;

library/core/src/unicode/unicode_data.rs

@@ -1,7 +1,6 @@
 ///! This file is generated by `./x run src/tools/unicode-table-generator`; do not edit manually!
 // Alphabetic      :  1723 bytes, 142707 codepoints in 755 ranges (U+0000AA - U+0323B0) using skiplist
 // Case_Ignorable  :  1043 bytes,   2744 codepoints in 447 ranges (U+0000A8 - U+0E01F0) using skiplist
-// Cc              :     0 bytes,     32 codepoints in   1 ranges (U+000080 - U+0000A0) using match
 // Grapheme_Extend :   887 bytes,   2193 codepoints in 375 ranges (U+000300 - U+0E01F0) using skiplist
 // Lowercase       :   933 bytes,   2543 codepoints in 674 ranges (U+0000AA - U+01E944) using bitset
 // Lt              :     0 bytes,     31 codepoints in  10 ranges (U+0001C5 - U+001FFD) using match
@@ -338,18 +337,6 @@ pub mod case_ignorable {
     }
 }
 
-#[rustfmt::skip]
-pub mod cc {
-    #[inline]
-    pub const fn lookup(c: char) -> bool {
-        debug_assert!(!c.is_ascii());
-        match c as u32 {
-            0x80..=0x9f => true,
-            _ => false,
-        }
-    }
-}
-
 #[rustfmt::skip]
 pub mod grapheme_extend {
     use super::ShortOffsetRunHeader;

src/tools/unicode-table-generator/src/main.rs

@@ -94,7 +94,6 @@ static PROPERTIES: &[&str] = &[
     "Case_Ignorable",
     "Grapheme_Extend",
     "White_Space",
-    "Cc",
     "N",
 ];