header     http.Header
	shouldFail bool
}{
	{header: generateHeader(0, 0), shouldFail: false},
	{header: generateHeader(1024, 0), shouldFail: false},
	{header: generateHeader(2048, 0), shouldFail: false},
	{header: generateHeader(8*1024+1, 0), shouldFail: true},
	{header: generateHeader(0, 1024), shouldFail: false},
	{header: generateHeader(0, 2048), shouldFail: true},

	reconstructParity          bool
	shouldFail                 bool
}{
	{dataBlocks: 2, parityBlocks: 2, missingData: 0, missingParity: 0, reconstructParity: true, shouldFail: false},
	{dataBlocks: 3, parityBlocks: 3, missingData: 1, missingParity: 0, reconstructParity: true, shouldFail: false},
	{dataBlocks: 4, parityBlocks: 4, missingData: 2, missingParity: 0, reconstructParity: false, shouldFail: false},

		os.Clearenv()
		for k, v := range test.Env {
			t.Setenv(k, v)
		}

		ok, err := IsPresent()
		if err != nil && !test.ShouldFail {
			t.Fatalf("Test %d: %v", i, err)
		}
		if err == nil && test.ShouldFail {
			t.Fatalf("Test %d: should have failed but succeeded", i)
		}

		if !test.ShouldFail && ok != test.IsPresent {
			t.Fatalf("Test %d: reported that KMS present=%v - want present=%v", i, ok, test.IsPresent)
		}
	}
}

	blocksize, size int64
	algorithm       BitrotAlgorithm
	shouldFail      bool
}{
	{dataBlocks: 2, disks: 4, offDisks: 1, badDisks: 0, badStaleDisks: 0, blocksize: int64(blockSizeV2), size: oneMiByte, algorithm: SHA256, shouldFail: false},                   // 0
	{dataBlocks: 3, disks: 6, offDisks: 2, badDisks: 0, badStaleDisks: 0, blocksize: int64(blockSizeV2), size: oneMiByte, algorithm: BLAKE2b512, shouldFail: false},               // 1

			metadata:   nil,
			shouldFail: true,
		},
	}

	// Validate if the extracting headers.
	for i, testCase := range testCases {
		metadata := make(map[string]string)
		err := extractMetadataFromMime(t.Context(), textproto.MIMEHeader(testCase.header), metadata)
		if err != nil && !testCase.shouldFail {
			t.Fatalf("Test %d failed to extract metadata: %v", i+1, err)
		}
		if err == nil && testCase.shouldFail {