原文链接：https://www.scala-sbt.org/1.x/docs/Mapping-Files.html

原文中有6段代码，其中第1，2，6段代码在windows上是跑不对的。现在将错误原因和修改代码一并给出：

第1，2段代码出错原因一样，是目录分隔符的原因：

• file()，relativeTo()，以及rebase(File)方法会将目录分隔符（/）转换成windows特有的分隔符（\），因此mappings的值变成String输出是：Vector((\a\b\C.scala,b\C.scala))
• 但是，expected是一个Seq[File,String]，其String部分写死了为b/C.scala, 所以expected的String输出是List((\a\b\C.scala,b/C.scala))
• ==比较的是内容，不考虑集合的类型，所以比较对象（mappings和expected）的类型是List还是Vector无所谓，但是内容不同就不同了。

第6段代码出错原因除了目录分割符问题之外，还因为在expected的定义里多了两个括号。

 

修改后能跑的6段代码集合如下：

import Path.relativeTo
val files: Seq[File] = file("/a/b/C.scala") :: Nil
val baseDirectories: Seq[File] = file("/a") :: Nil
val mappings: Seq[(File,String)] = files pair relativeTo(baseDirectories)

val expected = (file("/a/b/C.scala") -> "b\\C.scala") :: Nil
assert( mappings == expected )

import Path.rebase
val files2: Seq[File] = file("/a/b/C.scala") :: Nil
val baseDirectories2: File = file("/a")
val mappings2: Seq[(File,String)] = files2 pair rebase(baseDirectories2, "pre/")

val expected2 = (file("/a/b/C.scala") -> "pre/b\\C.scala") :: Nil
assert( mappings2 == expected2 )

val files3: Seq[File] = file("/a/b/C.scala") :: Nil
val baseDirectories3: Seq[File] = file("/a") :: Nil
val newBase3: File = file("/new/base")
val mappings3: Seq[(File,File)] = files3 pair rebase(baseDirectories3, newBase3)

val expected3 = (file("/a/b/C.scala") -> file("/new/base/b/C.scala") ) :: Nil
assert( mappings3 == expected3 )

import Path.flat
val files4: Seq[File] = file("/a/b/C.scala") :: Nil
val mappings4: Seq[(File,String)] = files4 pair flat

val expected4 = (file("/a/b/C.scala") -> "C.scala" ) :: Nil
assert( mappings4 == expected4 )

val files5: Seq[File] = file("/a/b/C.scala") :: Nil
val newBase5: File = file("/new/base")
val mappings5: Seq[(File,File)] = files5 pair flat(newBase5)

val expected5 = (file("/a/b/C.scala") -> file("/new/base/C.scala") ) :: Nil
assert( mappings5 == expected5 )

val files6: Seq[File] = file("/a/b/C.scala") :: file("/zzz/D.scala") :: Nil
val baseDirectories6: Seq[File] = file("/a") :: Nil
val mappings6: Seq[(File,String)] = files6 pair ( relativeTo(baseDirectories6) | flat )

val expected6 = (file("/a/b/C.scala") -> "b\\C.scala") :: (file("/zzz/D.scala") -> "D.scala") :: Nil
assert( mappings6 == expected6 )