Merge pull request nim-lang#937 from bobeff/bugfix/symlinks-checksums

Fix a bug when including symbolic link files to the package's checksum.

src/nimblepkg/checksums.nim

@@ -25,22 +25,36 @@ proc updateSha1Checksum(checksum: var Sha1State, fileName, filePath: string) =
     # directory from which no files are being installed.
     return
   checksum.update(fileName)
-  var file: File
-  try:
-    file = filePath.open(fmRead)
-  except IOError:
-    ## If the file cannot be open for reading do not count its content in the
-    ## checksum.
-    displayWarning(&"The file \"{filePath}\" cannot be open for reading.\n" &
-                    "Skipping it in the calculation of the checksum.")
-    return
-  defer: close(file)
-  const bufferSize = 8192
-  var buffer = newString(bufferSize)
-  while true:
-    var bytesRead = readChars(file, buffer)
-    if bytesRead == 0: break
-    checksum.update(buffer.toOpenArray(0, bytesRead - 1))
+  if symlinkExists(filePath):
+    # Check whether a file is a symbolic link and if so update the checksum with
+    # the path to the file that the link points to.
+    var linkPath: string
+    try:
+      linkPath = expandSymlink(filePath)
+    except OSError:
+      displayWarning(&"Cannot expand symbolic link \"{filePath}\".\n" &
+                      "Skipping it in the calculation of the checksum.")
+      return
+    checksum.update(linkPath)
+  else:
+    # Otherwise this is an ordinary file and we are adding its content to the
+    # checksum.
+    var file: File
+    try:
+      file = filePath.open(fmRead)
+    except IOError:
+      ## If the file cannot be open for reading do not count its content in the
+      ## checksum.
+      displayWarning(&"The file \"{filePath}\" cannot be open for reading.\n" &
+                      "Skipping it in the calculation of the checksum.")
+      return
+    defer: close(file)
+    const bufferSize = 8192
+    var buffer = newString(bufferSize)
+    while true:
+      var bytesRead = readChars(file, buffer)
+      if bytesRead == 0: break
+      checksum.update(buffer.toOpenArray(0, bytesRead - 1))
 
 proc calculateDirSha1Checksum*(dir: string): Sha1Hash =
   ## Recursively calculates the sha1 checksum of the contents of the directory

src/nimblepkg/download.nim

@@ -309,6 +309,25 @@ proc doDownloadTarball(url, downloadDir, version: string, queryRevision: bool):
     raise nimbleError(tryDoCmdExErrorMessage(cmd, output, exitCode))
   display("Completed", "unpacking " & filePath)
 
+  when defined(windows):
+    # On Windows symbolic link files are not being extracted properly by the
+    # `tar` command. They are extracted as empty files, but when cloning the
+    # repository with Git they are extracted as ordinary files with the link
+    # path in them. For that reason here we parse the tar file content to
+    # extract the symbolic links and add their paths manually to the content of
+    # their files.
+    let listCmd = &"{getTarExePath()} -ztvf {filePath} --force-local"
+    let (cmdOutput, cmdExitCode) = doCmdEx(listCmd)
+    if cmdExitCode != QuitSuccess:
+      raise nimbleError(tryDoCmdExErrorMessage(listCmd, cmdOutput, cmdExitCode))
+    for line in cmdOutput.splitLines():
+      if line.contains(" -> "):
+        let parts = line.split
+        let linkPath = parts[^1]
+        let linkNameParts = parts[^3].split('/')
+        let linkName = linkNameParts[1 .. ^1].foldl(a / b)
+        writeFile(downloadDir / linkName, linkPath)
+
   filePath.removeFile
   return if queryRevision: getRevision(url, version) else: notSetSha1Hash
 

src/nimblepkg/vcstools.nim

@@ -203,7 +203,12 @@ proc getVcsRevision*(dir: Path): Sha1Hash =
 proc getPackageFileListWithoutVcs(dir: Path): seq[string] =
   ## Recursively walks the directory `dir` and returns a list of files in it and
   ## its subdirectories.
-  for file in walkDirRec($dir, relative = true):
+  for file in walkDirRec($dir, yieldFilter = {pcFile, pcLinkToFile},
+                         relative = true):
+    when defined(windows):
+      # On windows relative paths to files which are included in the calculation
+      # of the package checksum must be the same as on POSIX systems.
+      let file = file.replace('\\', '/')
     result.add file
 
 proc getPackageFileList*(dir: Path): seq[string] =
@@ -1060,7 +1065,6 @@ username = John Doe <[email protected]>
       check not isValidSha1Hash($getVcsRevision(testNoVcsDir))
 
     test "getPackageFileList":
-      check getPackageFileList(testNoVcsDir) ==
-            @[testFile, testSubDirFile.normalizedPath]
+      check getPackageFileList(testNoVcsDir) == @[testFile, testSubDirFile]
 
     tearDownSuite(testNoVcsDir)