1 files changed, 51 insertions, 3 deletions

diff --git a/codegen/fold.zig b/codegen/fold.zig
index 7977e61..b3192e7 100644
--- a/codegen/fold.zig
+++ b/codegen/fold.zig
@@ -8,7 +8,51 @@ pub fn main() !void {
     defer arena.deinit();
     const allocator = arena.allocator();
 
-    // Process DerivedEastAsianWidth.txt
+    // Process DerivedCoreProperties.txt
+    var cp_file = try std.fs.cwd().openFile("data/unicode/DerivedCoreProperties.txt", .{});
+    defer cp_file.close();
+    var cp_buf = std.io.bufferedReader(cp_file.reader());
+    const cp_reader = cp_buf.reader();
+
+    var cp_map = std.AutoHashMap(u21, void).init(allocator);
+    defer cp_map.deinit();
+
+    var line_buf: [4096]u8 = undefined;
+
+    cp_lines: while (try cp_reader.readUntilDelimiterOrEof(&line_buf, '\n')) |line| {
+        if (line.len == 0 or line[0] == '#') continue;
+
+        const no_comment = if (std.mem.indexOfScalar(u8, line, '#')) |octo| line[0..octo] else line;
+
+        var field_iter = std.mem.tokenizeAny(u8, no_comment, "; ");
+        var current_code: [2]u21 = undefined;
+
+        var i: usize = 0;
+        while (field_iter.next()) |field| : (i += 1) {
+            switch (i) {
+                0 => {
+                    // Code point(s)
+                    if (std.mem.indexOf(u8, field, "..")) |dots| {
+                        current_code = .{
+                            try std.fmt.parseInt(u21, field[0..dots], 16),
+                            try std.fmt.parseInt(u21, field[dots + 2 ..], 16),
+                        };
+                    } else {
+                        const code = try std.fmt.parseInt(u21, field, 16);
+                        current_code = .{ code, code };
+                    }
+                },
+                1 => {
+                    // Core property
+                    if (!mem.eql(u8, field, "Changes_When_Casefolded")) continue :cp_lines;
+                    for (current_code[0]..current_code[1] + 1) |cp| try cp_map.put(@intCast(cp), {});
+                },
+                else => {},
+            }
+        }
+    }
+
+    // Process CaseFolding.txt
     var in_file = try std.fs.cwd().openFile("data/unicode/CaseFolding.txt", .{});
     defer in_file.close();
     var in_buf = std.io.bufferedReader(in_file.reader());
@@ -27,7 +71,6 @@ pub fn main() !void {
     const writer = out_comp.writer();
 
     const endian = builtin.cpu.arch.endian();
-    var line_buf: [4096]u8 = undefined;
 
     lines: while (try in_reader.readUntilDelimiterOrEof(&line_buf, '\n')) |line| {
         if (line.len == 0 or line[0] == '#') continue;
@@ -41,7 +84,12 @@ pub fn main() !void {
         var i: usize = 0;
         while (field_iter.next()) |field| : (i += 1) {
             switch (i) {
-                0 => cps[0] = try fmt.parseInt(u24, field, 16),
+                0 => {
+                    var cp = try fmt.parseInt(u21, field, 16);
+                    cp <<= 1;
+                    if (cp_map.contains(cp)) cp |= 1;
+                    cps[0] = cp;
+                },
 
                 1 => {
                     if (!mem.eql(u8, field, "C") and !mem.eql(u8, field, "F")) continue :lines;