Fix #567: Display package versions in sorted order (#688)

* Fix #567: Display package versions in sorted order

* Add docs

* Fix docs to focus on git tags

* Refactor to use version module

* Streamline docs

* Refactor to make things work in nim <= 0.19.6

* Improve code readability

src/nimblepkg/download.nim

@@ -2,8 +2,9 @@
 # BSD License. Look at license.txt for more info.
 
 import parseutils, os, osproc, strutils, tables, pegs, uri
-
 import packageinfo, packageparser, version, tools, common, options, cli
+from algorithm import SortOrder, sorted
+from sequtils import toSeq, filterIt, map
 
 type
   DownloadMethod* {.pure.} = enum
@@ -103,14 +104,21 @@ proc getTagsListRemote*(url: string, meth: DownloadMethod): seq[string] =
     # http://stackoverflow.com/questions/2039150/show-tags-for-remote-hg-repository
     raise newException(ValueError, "Hg doesn't support remote tag querying.")
 
-proc getVersionList*(tags: seq[string]): Table[Version, string] =
-  # Returns: TTable of version -> git tag name
-  result = initTable[Version, string]()
-  for tag in tags:
-    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 .. tag.len-1])] = tag
+proc getVersionList*(tags: seq[string]): OrderedTable[Version, string] =
+  ## Return an ordered table of Version -> git tag label.  Ordering is
+  ## in descending order with the most recent version first.
+  let taggedVers: seq[tuple[ver: Version, tag: string]] =
+    tags
+      .filterIt(it != "")
+      .map(proc(s: string): tuple[ver: Version, tag: string] =
+        # skip any chars before the version
+        let i = skipUntil(s, Digits)
+        # TODO: Better checking, tags can have any
+        # names. Add warnings and such.
+        result = (newVersion(s[i .. s.len-1]), s))
+      .sorted(proc(a, b: (Version, string)): int = cmp(a[0], b[0]),
+              SortOrder.Descending)
+  result = toOrderedTable[Version, string](taggedVers)
 
 proc getDownloadMethod*(meth: string): DownloadMethod =
   case meth
@@ -268,14 +276,8 @@ proc echoPackageVersions*(pkg: Package) =
     try:
       let versions = getTagsListRemote(pkg.url, downMethod).getVersionList()
       if versions.len > 0:
-        var vstr = ""
-        var i = 0
-        for v in values(versions):
-          if i != 0:
-            vstr.add(", ")
-          vstr.add(v)
-          i.inc
-        echo("  versions:    " & vstr)
+        let sortedVersions = toSeq(values(versions))
+        echo("  versions:    " & join(sortedVersions, ", "))
       else:
         echo("  versions:    (No versions tagged in the remote repository)")
     except OSError:
@@ -283,3 +285,19 @@ proc echoPackageVersions*(pkg: Package) =
   of DownloadMethod.hg:
     echo("  versions:    (Remote tag retrieval not supported by " &
         pkg.downloadMethod & ")")
+
+when isMainModule:
+  # Test version sorting
+  block:
+    let data = @["v9.0.0-taeyeon", "v9.0.1-jessica", "v9.2.0-sunny",
+                 "v9.4.0-tiffany", "v9.4.2-hyoyeon"]
+    let expected = toOrderedTable[Version, string]({
+      newVersion("9.4.2-hyoyeon"): "v9.4.2-hyoyeon",
+      newVersion("9.4.0-tiffany"): "v9.4.0-tiffany",
+      newVersion("9.2.0-sunny"): "v9.2.0-sunny",
+      newVersion("9.0.1-jessica"): "v9.0.1-jessica",
+      newVersion("9.0.0-taeyeon"): "v9.0.0-taeyeon"
+    })
+    doAssert expected == getVersionList(data)
+
+  echo("Everything works!")

src/nimblepkg/version.nim

@@ -93,6 +93,11 @@ proc `==`*(ver: Version, ver2: Version): bool =
     else:
       return false
 
+proc cmp*(a, b: Version): int =
+  if a < b: -1
+  elif a > b: 1
+  else: 0
+
 proc `<=`*(ver: Version, ver2: Version): bool =
   return (ver == ver2) or (ver < ver2)
 
@@ -272,7 +277,7 @@ proc newVREq*(ver: string): VersionRange =
   result.ver = newVersion(ver)
 
 proc findLatest*(verRange: VersionRange,
-        versions: Table[Version, string]): tuple[ver: Version, tag: string] =
+        versions: OrderedTable[Version, string]): tuple[ver: Version, tag: string] =
   result = (newVersion(""), "")
   for ver, tag in versions:
     if not withinRange(ver, verRange): continue
@@ -309,8 +314,11 @@ when isMainModule:
   doAssert(newVersion("") < newVersion("1.0.0"))
   doAssert(newVersion("") < newVersion("0.1.0"))
 
-  var versions = toTable[Version, string]({newVersion("0.1.1"): "v0.1.1",
-      newVersion("0.2.3"): "v0.2.3", newVersion("0.5"): "v0.5"})
+  var versions = toOrderedTable[Version, string]({
+    newVersion("0.1.1"): "v0.1.1",
+    newVersion("0.2.3"): "v0.2.3",
+    newVersion("0.5"): "v0.5"
+  })
   doAssert findLatest(parseVersionRange(">= 0.1 & <= 0.4"), versions) ==
       (newVersion("0.2.3"), "v0.2.3")