Zig side of js lexer testing

lexer_test.zig

const std = @import("std");
const print = std.debug.print;

const MAX_READ_BUFFER = 4294967295;

pub fn readFile(alloc: std.mem.Allocator, path: []const u8) ![:0]u8 {
const file = try std.fs.cwd().openFile(path, .{});
defer file.close();

const source_code = file.readToEndAllocOptions(
alloc,
MAX_READ_BUFFER,
null,
@alignOf(u16),
0,
);
return source_code;
}

pub fn main() !void {
var gpa = std.heap.GeneralPurposeAllocator(.{}){};
const alloc = gpa.allocator();

const args = try std.process.argsAlloc(alloc);

const source = try readFile(alloc, args[1]);
//\\const std = @import("std");
// ;
defer alloc.free(source);

//var toks = std.ArrayList(std.zig.Token).init(alloc);
//defer toks.deinit();

var tokenizer = std.zig.Tokenizer.init(source);
var should_stop = false;

const stdout = std.io.getStdOut().writer(); //needed for stdout

try stdout.print("[", .{});

//var toks = std.ArrayList(std.zig.Token);

while (!should_stop) {
const token = tokenizer.next();
// print("{s} \"{s}\"\n", .{ @tagName(token.tag), source[token.loc.start..token.loc.end] });
//try toks.append(token);

if (token.tag == .eof) {
should_stop = true;
try stdout.print("{{\"tag\": \"{s}\", \"loc\": {{\"start\": {}, \"end\": {}}}}}", .{ @tagName(token.tag), token.loc.start, token.loc.end });
} else {
try stdout.print("{{\"tag\": \"{s}\", \"loc\": {{\"start\": {}, \"end\": {}}}}},", .{ @tagName(token.tag), token.loc.start, token.loc.end });
}
}

try stdout.print("]\n", .{});
}