Commit 08e5daa7d5ff0226ced462308d06b3b17ee4472f | zig

author	Jonathan Marler <johnnymarler@gmail.com> 2021-07-01 22:23:10-06:00
committer	Veikka Tuominen <git@vexu.eu> 2021-07-15 20:37:16+03:00
log	08e5daa7d5ff0226ced462308d06b3b17ee4472f
tree	1a4693bfd12b81d099b5769a1cd29c6120267d1a
parent	ee173d512721df521b5a29bc939770e098931e21

Add std.unicode.fmtUtf16le

1 files changed, 43 insertions(+), 2 deletions(-)

lib
- std
  - unicode.zig

lib/std/unicode.zig+43-2

...	...	@@ -317,9 +317,9 @@ pub const Utf16LeIterator = struct {
317	317	assert(it.i <= it.bytes.len);
318	318	if (it.i == it.bytes.len) return null;
319	319	const c0: u21 = mem.readIntLittle(u16, it.bytes[it.i..][0..2]);
	320	it.i += 2;
320	321	if (c0 & ~@as(u21, 0x03ff) == 0xd800) {
321	322	// surrogate pair
322		it.i += 2;
323	323	if (it.i >= it.bytes.len) return error.DanglingSurrogateHalf;
324	324	const c1: u21 = mem.readIntLittle(u16, it.bytes[it.i..][0..2]);
325	325	if (c1 & ~@as(u21, 0x03ff) != 0xdc00) return error.ExpectedSecondSurrogateHalf;
...	...	@@ -328,7 +328,6 @@ pub const Utf16LeIterator = struct {
328	328	} else if (c0 & ~@as(u21, 0x03ff) == 0xdc00) {
329	329	return error.UnexpectedSecondSurrogateHalf;
330	330	} else {
331		it.i += 2;
332	331	return c0;
333	332	}
334	333	}
...	...	@@ -769,6 +768,48 @@ fn calcUtf16LeLen(utf8: []const u8) usize {
769	768	return dest_len;
770	769	}
771	770
	771	/// Print the given `utf16le` string
	772	fn formatUtf16le(
	773	utf16le: []const u16,
	774	comptime fmt: []const u8,
	775	options: std.fmt.FormatOptions,
	776	writer: anytype,
	777	) !void {
	778	const unknown_codepoint = 0xfffd;
	779	_ = fmt;
	780	_ = options;
	781	var buf: [300]u8 = undefined; // just a random size I chose
	782	var it = Utf16LeIterator.init(utf16le);
	783	var u8len: usize = 0;
	784	while (it.nextCodepoint() catch unknown_codepoint) \|codepoint\| {
	785	u8len += utf8Encode(codepoint, buf[u8len..]) catch
	786	utf8Encode(unknown_codepoint, buf[u8len..]) catch unreachable;
	787	if (u8len + 3 >= buf.len) {
	788	try writer.writeAll(buf[0..u8len]);
	789	u8len = 0;
	790	}
	791	}
	792	try writer.writeAll(buf[0..u8len]);
	793	}
	794
	795	/// Return a Formatter for a Utf16le string
	796	pub fn fmtUtf16le(utf16le: []const u16) std.fmt.Formatter(formatUtf16le) {
	797	return .{ .data = utf16le };
	798	}
	799
	800	test "fmtUtf16le" {
	801	const expectFmt = std.testing.expectFmt;
	802	try expectFmt("", "{}", .{fmtUtf16le(utf8ToUtf16LeStringLiteral(""))});
	803	try expectFmt("foo", "{}", .{fmtUtf16le(utf8ToUtf16LeStringLiteral("foo"))});
	804	try expectFmt("𐐷", "{}", .{fmtUtf16le(utf8ToUtf16LeStringLiteral("𐐷"))});
	805	try expectFmt("퟿", "{}", .{fmtUtf16le(&[_]u16{std.mem.readIntNative(u16, "\xff\xd7")})});
	806	try expectFmt("�", "{}", .{fmtUtf16le(&[_]u16{std.mem.readIntNative(u16, "\x00\xd8")})});
	807	try expectFmt("�", "{}", .{fmtUtf16le(&[_]u16{std.mem.readIntNative(u16, "\xff\xdb")})});
	808	try expectFmt("�", "{}", .{fmtUtf16le(&[_]u16{std.mem.readIntNative(u16, "\x00\xdc")})});
	809	try expectFmt("�", "{}", .{fmtUtf16le(&[_]u16{std.mem.readIntNative(u16, "\xff\xdf")})});
	810	try expectFmt("", "{}", .{fmtUtf16le(&[_]u16{std.mem.readIntNative(u16, "\x00\xe0")})});
	811	}
	812
772	813	test "utf8ToUtf16LeStringLiteral" {
773	814	{
774	815	const bytes = [_:0]u16{