From e84c5a721c45b18cb2f1d874e3f7e3c0db71c96d Mon Sep 17 00:00:00 2001
From: Dominik Picheta <dominikpicheta@googlemail.com>
Date: Fri, 20 Jun 2014 20:42:34 +0100
Subject: [PATCH] Fixes #25.

---
 src/babelpkg/download.nim |  6 +++---
 src/babelpkg/tools.nim    | 10 ++++++++++
 2 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/src/babelpkg/download.nim b/src/babelpkg/download.nim
index c20865a..89723fa 100644
--- a/src/babelpkg/download.nim
+++ b/src/babelpkg/download.nim
@@ -83,7 +83,7 @@ proc getTagsListRemote*(url: string, meth: TDownloadMethod): seq[string] =
   result = @[]
   case meth
   of TDownloadMethod.Git:
-    var (output, exitCode) = execCmdEx("git ls-remote --tags " & url)
+    var (output, exitCode) = doCmdEx("git ls-remote --tags " & url)
     if exitCode != QuitSuccess:
       raise newException(EOS, "Unable to query remote tags for " & url &
           ". Git returned: " & output)
@@ -122,9 +122,9 @@ proc getHeadName*(meth: TDownloadMethod): string =
 
 proc checkUrlType*(url: string): TDownloadMethod =
   ## Determines the download method based on the URL.
-  if execCmdEx("git ls-remote " & url).exitCode == QuitSuccess:
+  if doCmdEx("git ls-remote " & url).exitCode == QuitSuccess:
     return TDownloadMethod.Git
-  elif execCmdEx("hg identify " & url).exitCode == QuitSuccess:
+  elif doCmdEx("hg identify " & url).exitCode == QuitSuccess:
     return TDownloadMethod.Hg
   else:
     raise newException(EBabel, "Unable to identify url.")
diff --git a/src/babelpkg/tools.nim b/src/babelpkg/tools.nim
index 08ea08b..ee904b6 100644
--- a/src/babelpkg/tools.nim
+++ b/src/babelpkg/tools.nim
@@ -9,10 +9,20 @@ type
   EBabel* = object of EBase
 
 proc doCmd*(cmd: string) =
+  let bin = cmd.split(' ')[0]
+  if findExe(bin) == "":
+    raise newException(EBabel, "'" & bin & "' not in PATH.")
+
   let exitCode = execCmd(cmd)
   if exitCode != QuitSuccess:
     raise newException(EBabel, "Execution failed with exit code " & $exitCode)
 
+proc doCmdEx*(cmd: string): tuple[output: TaintedString, exitCode: int] =
+  let bin = cmd.split(' ')[0]
+  if findExe(bin) == "":
+    raise newException(EBabel, "'" & bin & "' not in PATH.")
+  return execCmdEx(cmd)
+
 template cd*(dir: string, body: stmt) =
   ## Sets the current dir to ``dir``, executes ``body`` and restores the
   ## previous working dir.