Add config helper function to find config files in a standardized manner.

cliutils.nimble

@@ -1,6 +1,6 @@
 # Package
 
-version       = "0.8.0"
+version       = "0.8.1"
 author        = "Jonathan Bernard"
 description   = "Helper functions for writing command line interfaces."
 license       = "MIT"

cliutils/config.nim

@@ -1,4 +1,5 @@
-import docopt, json, nre, os, strtabs, strutils
+import std/[json, nre, os, sequtils, strtabs, strutils]
+import docopt
 
 type
   CombinedConfig* = object
@@ -34,6 +35,22 @@ template walkFieldDefs*(t: NimNode, body: untyped) =
 #   cfgType.walkFieldDefs:
 #     let valLookup = quote do: `getVal`(
 
+proc initCombinedConfig*(
+    filename: string,
+    docopt: Table[string, Value] = initTable[string, Value]()
+  ): CombinedConfig =
+
+  result = CombinedConfig(docopt: docopt, json: parseFile(filename))
+
+proc findConfigFile*(name: string, otherLocations: seq[string] = @[]): string =
+  let cfgLocations = @[
+    $getEnv(name.strip(chars = {'.'}).toUpper()),
+    $getEnv("HOME") / name ] & otherLocations
+
+  result = cfgLocations.foldl(if fileExists(b): b else: a, "")
+  if result == "" or not fileExists(result):
+    raise newException(ValueError, "could not find configuration file")
+
 proc getVal*(cfg: CombinedConfig, key: string): string =
   let argKey = "--" & key
   let envKey = key.replace('-', '_').toUpper