Replace printables table with unicode_data.rs tables

This gets rid of the `printable.py` script,
ensuring that `unicode-table-generator` handles all our
Unicode data table generation needs.

There are also some drive-by documentation improvements
in `library/core/char/methods.rs`.

There is one change in behavior: we now consider all
characters with the `Default_Ignorable_Code_Point`
property to be unprintable. These characters can be
hidden/invisible otherwise.

I've elected to give each Unicode property its own table,
instead of merging them all into one.
This is slightly less efficient in terms of space,
but should allow us to expose these tables in the future
with public methods on `char`.

Author: Jules-Bertholet

library/core/src/char/methods.rs

@@ -2941,7 +2941,7 @@ impl Debug for str {
             let mut chars = rest.chars();
             if let Some(c) = chars.next() {
                 let esc = c.escape_debug_ext(EscapeDebugExtArgs {
-                    escape_grapheme_extended: true,
+                    escape_grapheme_extender: true,
                     escape_single_quote: false,
                     escape_double_quote: true,
                 });
@@ -2973,7 +2973,7 @@ impl Debug for char {
     fn fmt(&self, f: &mut Formatter<'_>) -> Result {
         f.write_char('\'')?;
         let esc = self.escape_debug_ext(EscapeDebugExtArgs {
-            escape_grapheme_extended: true,
+            escape_grapheme_extender: true,
             escape_single_quote: true,
             escape_double_quote: false,
         });

library/core/src/fmt/mod.rs

@@ -123,7 +123,7 @@ impl fmt::Debug for Debug<'_> {
                 let mut from = 0;
                 for (i, c) in valid.char_indices() {
                     let esc = c.escape_debug_ext(EscapeDebugExtArgs {
-                        escape_grapheme_extended: true,
+                        escape_grapheme_extender: true,
                         escape_single_quote: false,
                         escape_double_quote: true,
                     });

library/core/src/str/lossy.rs

@@ -3195,7 +3195,7 @@ impl_fn_for_zst! {
     #[derive(Clone)]
     struct CharEscapeDebugContinue impl Fn = |c: char| -> char::EscapeDebug {
         c.escape_debug_ext(EscapeDebugExtArgs {
-            escape_grapheme_extended: false,
+            escape_grapheme_extender: false,
             escape_single_quote: true,
             escape_double_quote: true
         })

library/core/src/str/mod.rs

@@ -9,15 +9,16 @@ 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::cf::lookup as Cf;
+pub(crate) use unicode_data::cn_planes_0_3::lookup as Cn_planes_0_3;
+pub(crate) use unicode_data::default_ignorable_code_point::lookup as Default_Ignorable_Code_Point;
 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;
 pub(crate) use unicode_data::n::lookup as N;
 pub(crate) use unicode_data::uppercase::lookup as Uppercase;
 pub(crate) use unicode_data::white_space::lookup as White_Space;
 
-pub(crate) mod printable;
-
 #[allow(unreachable_pub)]
 pub mod unicode_data;
 
@@ -27,8 +28,13 @@ pub mod unicode_data;
 /// New versions of Unicode are released regularly and subsequently all methods
 /// in the standard library depending on Unicode are updated. Therefore the
 /// behavior of some `char` and `str` methods and the value of this constant
-/// changes over time. This is *not* considered to be a breaking change.
+/// changes over time, within the boundaries of Unicode's [stability policies].
+/// This is *not* considered to be a breaking change.
+///
+/// [stability policies]: https://www.unicode.org/policies/stability_policy.html
 ///
 /// The version numbering scheme is explained in
-/// [Unicode 11.0 or later, Section 3.1 Versions of the Unicode Standard](https://www.unicode.org/versions/Unicode11.0.0/ch03.pdf#page=4).
+/// [Section 3.1 (Version Numbering)] of the Unicode Standard.
+///
+/// [Section 3.1 (Version Numbering)]: https://www.unicode.org/versions/latest/core-spec/chapter-3/#G49512
 pub const UNICODE_VERSION: (u8, u8, u8) = unicode_data::UNICODE_VERSION;