[lit] Avoid CRLFs in bash scripts on Windows

Native Windows Python will do line ending translation by default, which
we don't want in bash scripts.  If we're not native Windows Python, then
'b' is ignored.

llvm-svn: 177602

llvm/utils/lit/lit/TestRunner.py

@@ -277,7 +277,10 @@ def executeScript(test, litConfig, tmpBase, commands, cwd):
         script += '.bat'
 
     # Write script file
-    f = open(script,'w')
+    mode = 'w'
+    if litConfig.isWindows and not isWin32CMDEXE:
+      mode += 'b'  # Avoid CRLFs when writing bash scripts.
+    f = open(script, mode)
     if isWin32CMDEXE:
         f.write('\nif %ERRORLEVEL% NEQ 0 EXIT\n'.join(commands))
     else: