fn testCollapseRepeats(str: []const u8, elem: u8, expected: []const u8) !void
fn testCollapseRepeats(str: []const u8, elem: u8, expected: []const u8) !void { const mutable = try std.testing.allocator.dupe(u8, str); defer std.testing.allocator.free(mutable); try testing.expect(std.mem.eql(u8, collapseRepeats(u8, mutable, elem), expected)); }