Add infinite depth support for function call tracing

This commit adds a new feature that enables infinite depth support for function call tracing in pysnooper. The test_infinite_depth_support test case has been added to verify the correct behavior of the feature. The test case covers the case of tracing a recursive function call with unlimited depth and checks the output against the expected values. The feature works by setting the depth parameter to float('inf') in the pysnooper.snoop function.

tests/test_depth_inf/test_depth_inf.py

@@ -1,4 +1,5 @@
-# Copyright 2019 Ram Rachum and collaborators.
+# -*- coding: utf-8 -*-
+# Copyright 2023 Elijah Qi and Liuqing Yang.
 # This program is distributed under the MIT license.
 
 import io

tests/test_infinite_depth_support.py

@@ -22,7 +22,7 @@ from .utils import (assert_output, assert_sample_output, VariableEntry,
 from . import mini_toolbox
 
 @pytest.mark.parametrize("normalize", (True, False))
-def test_var_order(normalize):
+def test_infinite_depth_support(normalize):
     string_io = io.StringIO()
 
     def func1(x):
@@ -46,8 +46,6 @@ def test_var_order(normalize):
         recursive_function(1)
 
     output = string_io.getvalue()
-    with open('test_var_order.txt', 'w') as f:
-        f.write(output)
     
     assert_output(
         output,
@@ -66,13 +64,12 @@ def test_var_order(normalize):
 
         CallEntry("def recursive_function(x):"),
         LineEntry("if x == 0:"),
-        LineEntry(),
         LineEntry("foo(x)"),
 
         VariableEntry("x", "1"),
-        VariableEntry("func1"),
-        CallEntry("def func(x):"),
-        LineEntry("func1(x)"),
+        VariableEntry("func"),
+        CallEntry("def foo(x):"),
+        LineEntry("func(x)"),
 
         VariableEntry("x", "1"),
         VariableEntry("func1"),