implement TextEncoder

Author: krichprollsch

src/browser/encoding/text_encoder.zig

@@ -0,0 +1,60 @@
+// Copyright (C) 2023-2024  Lightpanda (Selecy SAS)
+//
+// Francis Bouvier <[email protected]>
+// Pierre Tachoire <[email protected]>
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as
+// published by the Free Software Foundation, either version 3 of the
+// License, or (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+const std = @import("std");
+
+const SessionState = @import("../env.zig").SessionState;
+
+pub const Interfaces = .{
+    TextEncoder,
+};
+
+// https://encoding.spec.whatwg.org/#interface-textencoder
+pub const TextEncoder = struct {
+    pub fn constructor() !TextEncoder {
+        return .{};
+    }
+
+    pub fn get_encoding(_: *const TextEncoder) []const u8 {
+        return "utf-8";
+    }
+
+    pub fn _encode(_: *const TextEncoder, v: []const u8, state: *SessionState) ![]u8 {
+        // ensure the input is a valid utf-8
+        if (!std.unicode.utf8ValidateSlice(v)) {
+            return error.InvalidUtf8Input;
+        }
+
+        // raw copy b/c we know the input is utf-8
+        const result = try state.arena.alloc(u16, v.len);
+        @memcpy(result, v);
+        return result;
+    }
+};
+
+const testing = @import("../../testing.zig");
+test "Browser.Encoding.TextEncoder" {
+    var runner = try testing.jsRunner(testing.tracking_allocator, .{});
+    defer runner.deinit();
+
+    try runner.testCases(&.{
+        .{ "var encoder = new TextEncoder();", "undefined" },
+        .{ "encoder.encoding;", "utf-8" },
+        .{ "encoder.encode('€');", "Uint8Array(3) [226, 130, 172]" },
+    }, .{});
+}

src/browser/env.zig

@@ -28,6 +28,7 @@ const WebApis = struct {
         @import("crypto/crypto.zig").Crypto,
         @import("console/console.zig").Console,
         @import("dom/dom.zig").Interfaces,
+        @import("encoding/text_encoder.zig").Interfaces,
         @import("events/event.zig").Interfaces,
         @import("html/html.zig").Interfaces,
         @import("iterator/iterator.zig").Interfaces,