Normalizer.eqlIgnoreCase compatibility caseless matching

1 files changed, 48 insertions, 0 deletions

diff --git a/src/FoldData.zig b/src/FoldData.zig
new file mode 100644
index 0000000..139c677
--- /dev/null
+++ b/src/FoldData.zig
@@ -0,0 +1,48 @@
+const std = @import("std");
+const builtin = @import("builtin");
+const compress = std.compress;
+const mem = std.mem;
+
+allocator: mem.Allocator,
+fold: [][]u21 = undefined,
+
+const Self = @This();
+
+pub fn init(allocator: mem.Allocator) !Self {
+    const decompressor = compress.deflate.decompressor;
+    const in_bytes = @embedFile("fold");
+    var in_fbs = std.io.fixedBufferStream(in_bytes);
+    var in_decomp = try decompressor(allocator, in_fbs.reader(), null);
+    defer in_decomp.deinit();
+    var reader = in_decomp.reader();
+
+    const endian = builtin.cpu.arch.endian();
+    var self = Self{
+        .allocator = allocator,
+        .fold = try allocator.alloc([]u21, 0x110000),
+    };
+
+    @memset(self.fold, &.{});
+
+    while (true) {
+        const len: u8 = try reader.readInt(u8, endian);
+        if (len == 0) break;
+        const cp = try reader.readInt(u24, endian);
+        self.fold[cp] = try allocator.alloc(u21, len - 1);
+        for (0..len - 1) |i| {
+            self.fold[cp][i] = @intCast(try reader.readInt(u24, endian));
+        }
+    }
+
+    return self;
+}
+
+pub fn deinit(self: *Self) void {
+    for (self.fold) |slice| self.allocator.free(slice);
+    self.allocator.free(self.fold);
+}
+
+/// Returns the case fold for `cp`.
+pub inline fn caseFold(self: Self, cp: u21) []const u21 {
+    return self.fold[cp];
+}