Add terminal.py from firebase-ios-sdk

Author: andrewheard

scripts/lib/terminal.py

@@ -0,0 +1,38 @@
+# Copyright 2019 Google
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import subprocess
+import threading
+
+
+_lock = threading.Lock()
+_columns = None
+
+
+def columns():
+  """Returns the number of columns in the terminal's display."""
+
+  global _columns
+  with _lock:
+    if _columns is None:
+      _columns = _find_terminal_columns()
+    return _columns
+
+
+def _find_terminal_columns():
+  try:
+    result = subprocess.check_output(['tput', 'cols'])
+    return int(result.rstrip())
+  except subprocess.CalledProcessError:
+    return 80