sbt/util/io/src/test/scala/CopySpec.scala

69 lines
2.2 KiB
Scala

package sbt
import java.io.File
import java.util.Arrays
import org.scalacheck._
import Prop._
import Arbitrary.arbLong
object CopySpec extends Properties("Copy") {
// set to 0.25 GB by default for success on most systems without running out of space.
// when modifying IO.copyFile, verify against 1 GB or higher, preferably > 4 GB
final val MaxFileSizeBits = 28
final val BufferSize = 1 * 1024 * 1024
val randomSize = Gen.choose(0, MaxFileSizeBits).map(1L << _)
val pow2Size = (0 to (MaxFileSizeBits - 1)).toList.map(1L << _)
val derivedSize = pow2Size.map(_ - 1) ::: pow2Size.map(_ + 1) ::: pow2Size
val fileSizeGen: Gen[Long] =
Gen.frequency(
80 -> Gen.oneOf(derivedSize),
8 -> randomSize,
1 -> Gen.value(0)
)
property("same contents") = forAll(fileSizeGen, arbLong.arbitrary) { (size: Long, seed: Long) =>
IO.withTemporaryDirectory { dir =>
val f1 = new File(dir, "source")
val f2 = new File(dir, "dest")
generate(seed = seed, size = size, file = f1)
IO.copyFile(f1, f2)
checkContentsSame(f1, f2)
true
}
}
def generate(seed: Long, size: Long, file: File) {
val rnd = new java.util.Random(seed)
val buffer = new Array[Byte](BufferSize)
def loop(offset: Long) {
val len = math.min(size - offset, BufferSize)
if (len > 0) {
rnd.nextBytes(buffer)
IO.append(file, buffer)
loop(offset + len)
}
}
if (size == 0L) IO.touch(file) else loop(0)
}
def checkContentsSame(f1: File, f2: File) {
val len = f1.length
assert(len == f2.length, "File lengths differ: " + (len, f2.length).toString + " for " + (f1, f2).toString)
Using.fileInputStream(f1) { in1 =>
Using.fileInputStream(f2) { in2 =>
val buffer1 = new Array[Byte](BufferSize)
val buffer2 = new Array[Byte](BufferSize)
def loop(offset: Long): Unit = if (offset < len) {
val read1 = in1.read(buffer1)
val read2 = in2.read(buffer2)
assert(read1 == read2, "Read " + (read1, read2).toString + " bytes from " + (f1, f2).toString)
assert(Arrays.equals(buffer1, buffer2), "Contents differed.")
loop(offset + read1)
}
loop(0)
}
}
}
}