Fixes problems caused by "" being present in the version list.

Specifically, not being able to install nim-vorbis.

download.nim

@@ -58,10 +58,14 @@ proc getTagsList(dir: string, meth: TDownloadMethod): seq[string] =
   if output.len > 0:
     case meth
     of TDownloadMethod.Git:
-      result = output.splitLines()
+      result = @[]
+      for i in output.splitLines():
+        if i == "": continue
+        result.add(i)
     of TDownloadMethod.Hg:
       result = @[]
       for i in output.splitLines():
+        if i == "": continue
         var tag = ""
         discard parseUntil(i, tag, ' ')
         if tag != "tip":
@@ -91,9 +95,10 @@ proc getVersionList*(tags: seq[string]): TTable[TVersion, string] =
   # Returns: TTable of version -> git tag name
   result = initTable[TVersion, string]()
   for tag in tags:
-    let i = skipUntil(tag, digits) # skip any chars before the version
-    # TODO: Better checking, tags can have any names. Add warnings and such.
-    result[newVersion(tag[i .. -1])] = tag
+    if tag != "":
+      let i = skipUntil(tag, digits) # skip any chars before the version
+      # TODO: Better checking, tags can have any names. Add warnings and such.
+      result[newVersion(tag[i .. -1])] = tag
 
 proc getDownloadMethod*(meth: string): TDownloadMethod =
   case meth

packageinfo.nim

@@ -281,6 +281,8 @@ proc findPkg*(pkglist: seq[tuple[pkginfo: TPackageInfo, meta: TMetaData]],
   ## of ``dep.ver``. ``True`` is returned if a package is found. If multiple
   ## packages are found the newest one is returned (the one with the highest
   ## version number)
+  ##
+  ## **Note**: dep.name here could be a URL, hence the need for pkglist.meta. 
   for pkg in pkglist:
     if pkg.pkginfo.name != dep.name and pkg.meta.url != dep.name: continue
     if withinRange(newVersion(pkg.pkginfo.version), dep.ver):

tools.nim

@@ -62,8 +62,15 @@ proc getDownloadDirName*(url: string, verRange: PVersionRange): string =
     of strutils.Letters, strutils.Digits:
       result.add i
     else: nil
-  result.add "_"
-  result.add getSimpleString(verRange)
+    
+  let verSimple = getSimpleString(verRange)
+  if verSimple != "":
+    result.add "_"
+    result.add verSimple
 
 proc getDownloadDirName*(pkg: TPackage, verRange: PVersionRange): string =
-  result = pkg.name & "_" & verRange.getSimpleString
+  result = pkg.name
+  let verSimple = getSimpleString(verRange)
+  if verSimple != "":
+    result.add "_"
+    result.add verSimple