[LIT] Decode string result in lit.util.capture

Summary: I think this is probably a bug, but I'm putting this up for review just to be sure. I think that `lit.util.capture` should decode the resulting string in the same way `lit.util.executeCommand` does.

Reviewers: ddunbar, EricWF

Reviewed By: EricWF

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D6769

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225681 91177308-0d34-0410-b5e6-96231b3b80d8

utils/lit/lit/util.py

@@ -16,6 +16,12 @@ def to_string(bytes):
         return bytes
     return to_bytes(bytes)
 
+def convert_string(bytes):
+    try:
+        return to_string(bytes.decode('utf-8'))
+    except UnicodeError:
+        return str(bytes)
+
 def detectCPUs():
     """
     Detects the number of CPUs on a system. Cribbed from pp.
@@ -60,7 +66,7 @@ def capture(args, env=None):
     p = subprocess.Popen(args, stdout=subprocess.PIPE, stderr=subprocess.PIPE,
                          env=env)
     out,_ = p.communicate()
-    return out
+    return convert_string(out)
 
 def which(command, paths = None):
     """which(command, [paths]) - Look up the given command in the paths string
@@ -166,14 +172,8 @@ def executeCommand(command, cwd=None, env=None):
         raise KeyboardInterrupt
 
     # Ensure the resulting output is always of string type.
-    try:
-        out = to_string(out.decode('utf-8'))
-    except:
-        out = str(out)
-    try:
-        err = to_string(err.decode('utf-8'))
-    except:
-        err = str(err)
+    out = convert_string(out)
+    err = convert_string(err)
 
     return out, err, exitCode