You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: helpers_test.go
    path of file: ./repos/livekit/pkg/sfu/buffer
    
    the code of the file until where you have to start completion: // Copyright 2023 LiveKit, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You 
    
func TestVP8Helper_Unmarshal(t *testing.T) {
	type args struct {
		payload []byte
	}
	tests := []struct {
		name            string
		args            args
		wantErr         bool
		checkTemporal   bool
		temporalSupport bool
		checkKeyFrame   bool
		keyFrame        bool
		checkPictureID  bool
		pictureID       uint16
		checkTlzIdx     bool
		tlzIdx          uint8
		checkTempID     bool
		temporalID      uint8
	}{
		{
			name:    "Empty or nil payload must return error",
			args:    args{payload: []byte{}},
			wantErr: true,
		},
		{
			name:            "Temporal must be supported by setting T bit to 1",
			args:            args{payload: []byte{0xff, 0x20, 0x1, 0x2, 0x3, 0x4}},
			checkTemporal:   true,
			temporalSupport: true,
		},
		{
			name:           "Picture must be ID 7 bits by setting M bit to 0 and present by I bit set to 1",
			args:           args{payload: []byte{0xff, 0xff, 0x11, 0x2, 0x3, 0x4}},
			checkPictureID: true,
			pictureID:      17,
		},
		{
			name:           "Picture ID must be 15 bits by setting M bit to 1 and present by I bit set to 1",
			args:           args{payload: []byte{0xff, 0xff, 0x92, 0x67, 0x3, 0x4, 0x5}},
			checkPictureID: true,
			pictureID:      4711,
		},
		{
			name:        "Temporal level zero index must be present if L set to 1",
			args:        args{payload: []byte{0xff, 0xff, 0xff, 0xfd, 0xb4, 0x4, 0x5}},
			checkTlzIdx: true,
			tlzIdx:      180,
		},
		{
			name:        "Temporal index must be present and used if T bit set to 1",
			args:        args{payload: []byte{0xff, 0xff, 0xff, 0xfd, 0xb4, 0x9f, 0x5, 0x6}},
			checkTempID: true,
			temporalID:  2,
		},
		{
			name:          "Check if packet is a keyframe by looking at P bit set to 0",
			args:          args{payload: []byte{0xff, 0xff, 0xff, 0xfd, 0xb4, 0x9f, 0x94, 0x1}},
			checkKeyFrame: true,
			keyFrame:      true,
		},
	}
	for _, tt := range tests {
		tt := tt
		t.Run(tt.name, func(t *testing.T) {
			p := &VP8{}
			if err := p.Unmarshal(tt.args.payload); (err != nil) != tt.wantErr {
				t.Errorf("Unmarshal() error = %v, wantErr %v", err, tt.wantErr)
			}
			if tt.checkTemporal {
				require.Equal(t, tt.temporalSupport, p.T)
			}
			if tt.checkKeyFrame {
				require.Equal(t, tt.keyFrame, p.IsKeyFrame)
			}
			if tt.checkPictureID {
				require.Equal(t, tt.pictureID, p.PictureID)
			}
			if tt.checkTlzIdx {
				require.Equal(t, tt.tlzIdx, p.TL0PICIDX)
			}
			if tt.checkTempID {
				require.Equal(t, tt.temporalID, p.TID)
			}
		})
	}
}