patman: Move capture_sys_output() into terminal and rename

This function is sometimes useful outside tests. Also it can affect how
terminal output is done, e.g. whether ANSI characters should be emitted
or not.

Move it out of the test_util package and into terminal.

Signed-off-by: Simon Glass <sjg@chromium.org>

1 files changed, 16 insertions, 0 deletions

diff --git a/tools/u_boot_pylib/terminal.py b/tools/u_boot_pylib/terminal.py
index 2cd5a54ab52..84531831760 100644
--- a/tools/u_boot_pylib/terminal.py
+++ b/tools/u_boot_pylib/terminal.py
@@ -7,6 +7,8 @@
 This module handles terminal interaction including ANSI color codes.
 """
 
+from contextlib import contextmanager
+from io import StringIO
 import os
 import re
 import shutil
@@ -271,3 +273,17 @@ class Color(object):
             base = self.BRIGHT_START if bright else self.NORMAL_START
             start = base % (color + 30)
         return start + text + self.RESET
+
+
+# Use this to suppress stdout/stderr output:
+# with terminal.capture() as (stdout, stderr)
+#   ...do something...
+@contextmanager
+def capture():
+    capture_out, capture_err = StringIO(), StringIO()
+    old_out, old_err = sys.stdout, sys.stderr
+    try:
+        sys.stdout, sys.stderr = capture_out, capture_err
+        yield capture_out, capture_err
+    finally:
+        sys.stdout, sys.stderr = old_out, old_err