From 2c14444bc9054604b71ad5b0e8fb3c3e34877e58 Mon Sep 17 00:00:00 2001 From: Jose Colon Rodriguez Date: Sun, 18 Feb 2024 11:26:00 -0400 Subject: Grapheme -> grapheme --- src/Grapheme.zig | 332 ------------------------------------------------------- 1 file changed, 332 deletions(-) delete mode 100644 src/Grapheme.zig (limited to 'src/Grapheme.zig') diff --git a/src/Grapheme.zig b/src/Grapheme.zig deleted file mode 100644 index f013aba..0000000 --- a/src/Grapheme.zig +++ /dev/null @@ -1,332 +0,0 @@ -const std = @import("std"); -const unicode = std.unicode; - -const CodePoint = @import("code_point").CodePoint; -const CodePointIterator = @import("code_point").Iterator; -const gbp = @import("gbp"); - -/// `Grapheme` represents a Unicode grapheme cluster by its length and offset in the source bytes. -pub const Grapheme = struct { - len: u8, - offset: u32, - - /// `bytes` returns the slice of bytes that correspond to - /// this grapheme cluster in `src`. - pub fn bytes(self: Grapheme, src: []const u8) []const u8 { - return src[self.offset..][0..self.len]; - } -}; - -/// `Iterator` iterates a sting of UTF-8 encoded bytes one grapheme cluster at-a-time. -pub const Iterator = struct { - buf: [2]?CodePoint = .{ null, null }, - cp_iter: CodePointIterator, - - const Self = @This(); - - /// Assumes `src` is valid UTF-8. - pub fn init(str: []const u8) Self { - var self = Self{ .cp_iter = CodePointIterator{ .bytes = str } }; - self.advance(); - return self; - } - - fn advance(self: *Self) void { - self.buf[0] = self.buf[1]; - self.buf[1] = self.cp_iter.next(); - } - - pub fn next(self: *Self) ?Grapheme { - self.advance(); - - // If no more - if (self.buf[0] == null) return null; - // If last one - if (self.buf[1] == null) return Grapheme{ .len = self.buf[0].?.len, .offset = self.buf[0].?.offset }; - // If ASCII - if (self.buf[0].?.code != '\r' and self.buf[0].?.code < 128 and self.buf[1].?.code < 128) { - return Grapheme{ .len = self.buf[0].?.len, .offset = self.buf[0].?.offset }; - } - - const gc_start = self.buf[0].?.offset; - var gc_len: u8 = self.buf[0].?.len; - var state = State{}; - - if (graphemeBreak( - self.buf[0].?.code, - self.buf[1].?.code, - &state, - )) return Grapheme{ .len = gc_len, .offset = gc_start }; - - while (true) { - self.advance(); - if (self.buf[0] == null) break; - - gc_len += self.buf[0].?.len; - - if (graphemeBreak( - self.buf[0].?.code, - if (self.buf[1]) |ncp| ncp.code else 0, - &state, - )) break; - } - - return Grapheme{ .len = gc_len, .offset = gc_start }; - } -}; - -// Predicates -fn isBreaker(cp: u21) bool { - // Extract relevant properties. - const cp_props_byte = gbp.stage_3[gbp.stage_2[gbp.stage_1[cp >> 8] + (cp & 0xff)]]; - const cp_gbp_prop: gbp.Gbp = @enumFromInt(cp_props_byte >> 4); - return cp == '\x0d' or cp == '\x0a' or cp_gbp_prop == .Control; -} - -fn isIgnorable(cp: u21) bool { - const cp_gbp_prop = gbp.stage_3[gbp.stage_2[gbp.stage_1[cp >> 8] + (cp & 0xff)]]; - return cp_gbp_prop == .extend or cp_gbp_prop == .spacing or cp == '\u{200d}'; -} - -// Grapheme break state. -const State = struct { - bits: u3 = 0, - - // Extended Pictographic (emoji) - fn hasXpic(self: State) bool { - return self.bits & 1 == 1; - } - fn setXpic(self: *State) void { - self.bits |= 1; - } - fn unsetXpic(self: *State) void { - self.bits ^= 1; - } - - // Regional Indicatior (flags) - fn hasRegional(self: State) bool { - return self.bits & 2 == 2; - } - fn setRegional(self: *State) void { - self.bits |= 2; - } - fn unsetRegional(self: *State) void { - self.bits ^= 2; - } - - // Indic Conjunct - fn hasIndic(self: State) bool { - return self.bits & 4 == 4; - } - fn setIndic(self: *State) void { - self.bits |= 4; - } - fn unsetIndic(self: *State) void { - self.bits ^= 4; - } -}; - -/// `graphemeBreak` returns true only if a grapheme break point is required -/// between `cp1` and `cp2`. `state` should start out as 0. If calling -/// iteratively over a sequence of code points, this function must be called -/// IN ORDER on ALL potential breaks in a string. -/// Modeled after the API of utf8proc's `utf8proc_grapheme_break_stateful`. -/// https://github.com/JuliaStrings/utf8proc/blob/2bbb1ba932f727aad1fab14fafdbc89ff9dc4604/utf8proc.h#L599-L617 -pub fn graphemeBreak( - cp1: u21, - cp2: u21, - state: *State, -) bool { - // Extract relevant properties. - const cp1_props_byte = gbp.stage_3[gbp.stage_2[gbp.stage_1[cp1 >> 8] + (cp1 & 0xff)]]; - const cp1_gbp_prop: gbp.Gbp = @enumFromInt(cp1_props_byte >> 4); - const cp1_indic_prop: gbp.Indic = @enumFromInt((cp1_props_byte >> 1) & 0x7); - const cp1_is_emoji = cp1_props_byte & 1 == 1; - - const cp2_props_byte = gbp.stage_3[gbp.stage_2[gbp.stage_1[cp2 >> 8] + (cp2 & 0xff)]]; - const cp2_gbp_prop: gbp.Gbp = @enumFromInt(cp2_props_byte >> 4); - const cp2_indic_prop: gbp.Indic = @enumFromInt((cp2_props_byte >> 1) & 0x7); - const cp2_is_emoji = cp2_props_byte & 1 == 1; - - // GB11: Emoji Extend* ZWJ x Emoji - if (!state.hasXpic() and cp1_is_emoji) state.setXpic(); - // GB9c: Indic Conjunct Break - if (!state.hasIndic() and cp1_indic_prop == .Consonant) state.setIndic(); - - // GB3: CR x LF - if (cp1 == '\r' and cp2 == '\n') return false; - - // GB4: Control - if (isBreaker(cp1)) return true; - - // GB11: Emoji Extend* ZWJ x Emoji - if (state.hasXpic() and - cp1_gbp_prop == .ZWJ and - cp2_is_emoji) - { - state.unsetXpic(); - return false; - } - - // GB9b: x (Extend | ZWJ) - if (cp2_gbp_prop == .Extend or cp2_gbp_prop == .ZWJ) return false; - - // GB9a: x Spacing - if (cp2_gbp_prop == .SpacingMark) return false; - - // GB9b: Prepend x - if (cp1_gbp_prop == .Prepend and !isBreaker(cp2)) return false; - - // GB12, GB13: RI x RI - if (cp1_gbp_prop == .Regional_Indicator and cp2_gbp_prop == .Regional_Indicator) { - if (state.hasRegional()) { - state.unsetRegional(); - return true; - } else { - state.setRegional(); - return false; - } - } - - // GB6: Hangul L x (L|V|LV|VT) - if (cp1_gbp_prop == .L) { - if (cp2_gbp_prop == .L or - cp2_gbp_prop == .V or - cp2_gbp_prop == .LV or - cp2_gbp_prop == .LVT) return false; - } - - // GB7: Hangul (LV | V) x (V | T) - if (cp1_gbp_prop == .LV or cp1_gbp_prop == .V) { - if (cp2_gbp_prop == .V or - cp2_gbp_prop == .T) return false; - } - - // GB8: Hangul (LVT | T) x T - if (cp1_gbp_prop == .LVT or cp1_gbp_prop == .T) { - if (cp2_gbp_prop == .T) return false; - } - - // GB9c: Indic Conjunct Break - if (state.hasIndic() and - cp1_indic_prop == .Consonant and - (cp2_indic_prop == .Extend or cp2_indic_prop == .Linker)) - { - return false; - } - - if (state.hasIndic() and - cp1_indic_prop == .Extend and - cp2_indic_prop == .Linker) - { - return false; - } - - if (state.hasIndic() and - (cp1_indic_prop == .Linker or cp1_gbp_prop == .ZWJ) and - cp2_indic_prop == .Consonant) - { - state.unsetIndic(); - return false; - } - - return true; -} - -test "Segmentation GraphemeIterator" { - const allocator = std.testing.allocator; - var file = try std.fs.cwd().openFile("GraphemeBreakTest.txt", .{}); - defer file.close(); - var buf_reader = std.io.bufferedReader(file.reader()); - var input_stream = buf_reader.reader(); - - var buf: [4096]u8 = undefined; - var line_no: usize = 1; - - while (try input_stream.readUntilDelimiterOrEof(&buf, '\n')) |raw| : (line_no += 1) { - // Skip comments or empty lines. - if (raw.len == 0 or raw[0] == '#' or raw[0] == '@') continue; - - // Clean up. - var line = std.mem.trimLeft(u8, raw, "÷ "); - if (std.mem.indexOf(u8, line, " ÷\t#")) |octo| { - line = line[0..octo]; - } - // Iterate over fields. - var want = std.ArrayList(Grapheme).init(allocator); - defer want.deinit(); - - var all_bytes = std.ArrayList(u8).init(allocator); - defer all_bytes.deinit(); - - var graphemes = std.mem.split(u8, line, " ÷ "); - var bytes_index: u32 = 0; - - while (graphemes.next()) |field| { - var code_points = std.mem.split(u8, field, " "); - var cp_buf: [4]u8 = undefined; - var cp_index: u32 = 0; - var gc_len: u8 = 0; - - while (code_points.next()) |code_point| { - if (std.mem.eql(u8, code_point, "×")) continue; - const cp: u21 = try std.fmt.parseInt(u21, code_point, 16); - const len = try unicode.utf8Encode(cp, &cp_buf); - try all_bytes.appendSlice(cp_buf[0..len]); - cp_index += len; - gc_len += len; - } - - try want.append(Grapheme{ .len = gc_len, .offset = bytes_index }); - bytes_index += cp_index; - } - - // std.debug.print("\nline {}: {s}\n", .{ line_no, all_bytes.items }); - var iter = Iterator.init(all_bytes.items); - - // Chaeck. - for (want.items) |want_gc| { - const got_gc = (iter.next()).?; - try std.testing.expectEqualStrings( - want_gc.bytes(all_bytes.items), - got_gc.bytes(all_bytes.items), - ); - } - } -} - -test "Segmentation comptime GraphemeIterator" { - const want = [_][]const u8{ "H", "é", "l", "l", "o" }; - - comptime { - const src = "Héllo"; - var ct_iter = Iterator.init(src); - var i = 0; - while (ct_iter.next()) |grapheme| : (i += 1) { - try std.testing.expectEqualStrings(grapheme.bytes(src), want[i]); - } - } -} - -test "Segmentation ZWJ and ZWSP emoji sequences" { - const seq_1 = "\u{1F43B}\u{200D}\u{2744}\u{FE0F}"; - const seq_2 = "\u{1F43B}\u{200D}\u{2744}\u{FE0F}"; - const with_zwj = seq_1 ++ "\u{200D}" ++ seq_2; - const with_zwsp = seq_1 ++ "\u{200B}" ++ seq_2; - const no_joiner = seq_1 ++ seq_2; - - var ct_iter = Iterator.init(with_zwj); - var i: usize = 0; - while (ct_iter.next()) |_| : (i += 1) {} - try std.testing.expectEqual(@as(usize, 1), i); - - ct_iter = Iterator.init(with_zwsp); - i = 0; - while (ct_iter.next()) |_| : (i += 1) {} - try std.testing.expectEqual(@as(usize, 3), i); - - ct_iter = Iterator.init(no_joiner); - i = 0; - while (ct_iter.next()) |_| : (i += 1) {} - try std.testing.expectEqual(@as(usize, 2), i); -} -- cgit v1.2.3