From c2e44fb5835535df61c2777cd8accda36fadbbd5 Mon Sep 17 00:00:00 2001
From: Ram Rachum <ram@rachum.com>
Date: Wed, 17 Jul 2019 09:19:37 +0300
Subject: [PATCH] Improve ensure_tuple

---
 pysnooper/pycompat.py                 |  5 +++++
 pysnooper/tracer.py                   |  4 +++-
 pysnooper/utils.py                    | 10 ++++++----
 pysnooper/variables.py                | 11 +++++++++++
 tests/test_utils/__init__.py          |  0
 tests/test_utils/test_ensure_tuple.py | 19 +++++++++++++++++++
 6 files changed, 44 insertions(+), 5 deletions(-)
 create mode 100644 tests/test_utils/__init__.py
 create mode 100644 tests/test_utils/test_ensure_tuple.py

diff --git a/pysnooper/pycompat.py b/pysnooper/pycompat.py
index de0a472..1748ccd 100644
--- a/pysnooper/pycompat.py
+++ b/pysnooper/pycompat.py
@@ -54,3 +54,8 @@ if PY3:
 else:
     string_types = (basestring,)
     text_type = unicode
+
+try:
+    from collections import abc as collections_abc
+except ImportError: # Python 2.7
+    import collections as collections_abc
diff --git a/pysnooper/tracer.py b/pysnooper/tracer.py
index c4a6413..5d91aeb 100644
--- a/pysnooper/tracer.py
+++ b/pysnooper/tracer.py
@@ -261,7 +261,9 @@ class Tracer:
             calling_frame.f_trace = self.trace
             self.target_frames.add(calling_frame)
 
-        stack = self.thread_local.__dict__.setdefault('original_trace_functions', [])
+        stack = self.thread_local.__dict__.setdefault(
+            'original_trace_functions', []
+        )
         stack.append(sys.gettrace())
         sys.settrace(self.trace)
 
diff --git a/pysnooper/utils.py b/pysnooper/utils.py
index 8c27006..b569698 100644
--- a/pysnooper/utils.py
+++ b/pysnooper/utils.py
@@ -4,7 +4,7 @@
 import abc
 
 import sys
-from .pycompat import ABC, string_types
+from .pycompat import ABC, string_types, collections_abc
 
 MAX_VARIABLE_LENGTH = 100
 MAX_EXCEPTION_LENGTH = 200
@@ -78,9 +78,11 @@ def truncate(string, max_length):
 
 
 def ensure_tuple(x):
-    if isinstance(x, string_types):
-        x = (x,)
-    return tuple(x)
+    if isinstance(x, collections_abc.Iterable) and \
+                                               not isinstance(x, string_types):
+        return tuple(x)
+    else:
+        return (x,)
 
 
 
diff --git a/pysnooper/variables.py b/pysnooper/variables.py
index 8468c6b..fe0176a 100644
--- a/pysnooper/variables.py
+++ b/pysnooper/variables.py
@@ -38,6 +38,17 @@ class BaseVariable(pycompat.ABC):
     def _items(self, key):
         raise NotImplementedError
 
+    @property
+    def _fingerprint(self):
+        return (type(self), self.source, self.exclude)
+
+    def __hash__(self):
+        return hash(self._fingerprint)
+
+    def __eq__(self, other):
+        return (isinstance(other, BaseVariable) and
+                                       self._fingerprint == other._fingerprint)
+
 
 class CommonVariable(BaseVariable):
     def _items(self, main_value):
diff --git a/tests/test_utils/__init__.py b/tests/test_utils/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/tests/test_utils/test_ensure_tuple.py b/tests/test_utils/test_ensure_tuple.py
new file mode 100644
index 0000000..aa6e526
--- /dev/null
+++ b/tests/test_utils/test_ensure_tuple.py
@@ -0,0 +1,19 @@
+# Copyright 2019 Ram Rachum and collaborators.
+# This program is distributed under the MIT license.
+
+import pysnooper
+from pysnooper.utils import ensure_tuple
+
+def test_ensure_tuple():
+    x1 = ('foo', ('foo',), ['foo'], {'foo'})
+    assert set(map(ensure_tuple, x1)) == {('foo',)}
+
+    x2 = (pysnooper.Keys('foo'), (pysnooper.Keys('foo'),),
+          [pysnooper.Keys('foo')], {pysnooper.Keys('foo')})
+
+    assert set(map(ensure_tuple, x2)) == {(pysnooper.Keys('foo'),)}
+
+
+
+
+