Take package path as an optional argument

nim_lk.nimble

@@ -3,6 +3,6 @@ bin = @["nim_lk"]
 description = "Tool for generating Nim lockfiles"
 license = "BSD-3-Clause"
 srcDir = "src"
-version = "20231021"
+version = "20231031"
 
 requires "nim >= 2.0.0", "preserves >= 20231021"

src/nim_lk.nim

@@ -7,7 +7,7 @@ import nimblepkg/common,
   nimblepkg/packageparser,
   nimblepkg/version
 
-import std/[algorithm, deques, httpclient, json, os, osproc, parseutils, streams, strutils, uri]
+import std/[algorithm, cmdline, deques, httpclient, json, os, osproc, parseutils, streams, strutils, uri]
 import preserves
 
 const githubPackagesUrl =
@@ -217,12 +217,12 @@ proc getPackgeUri(name: string): tuple[uri: string, meth: string] =
           quit("Failed to parse shit JSON " & $e)
     inc i
 
-proc generateLockfile(): Preserve =
+proc generateLockfile(directoryPath: string): Preserve =
   result = initDictionary()
   var
     deps = initSequence()
     pending: Deque[PkgTuple]
-  collectRequires(pending, getCurrentDir())
+  collectRequires(pending, directoryPath)
   while pending.len > 0:
     let batchLen = pending.len
     for i in 1..batchLen:
@@ -259,9 +259,16 @@ proc generateLockfile(): Preserve =
   result["depends".toPreserve] = deps
 
 proc main =
+  var packagePath = getCurrentDir()
+  case paramCount()
+  of 0: discard
+  of 1:
+    packagePath = commandLineParams()[0]
+  else:
+    quit "no more than a single package path may be specified"
   var
     stream = newFileStream(stdout)
-    lockInfo = generateLockfile()
+    lockInfo = generateLockfile(packagePath)
   cannonicalize(lockInfo)
   writeText(stream, lockInfo, textJson)
   writeLine(stream)