I would expect this to pass.

Author: nedtwigg

python/example-pytest-selfie/tests/binary_test.py

@@ -4,7 +4,6 @@
 import pytest
 from selfie_lib import expect_selfie
 
-
 def test_empty_binary_base64():
     """Test base64 encoding of empty byte array"""
     expect_selfie(bytes()).to_be_base64("")
@@ -21,41 +20,31 @@ def test_large_binary_base64():
 def test_binary_file():
     """Test writing binary data to a file"""
     data = b"test binary data"
-    expect_selfie(data).to_be_file("test_binary.bin")
+    expect_selfie(data).to_be_file("tests/binary_test__test_binary_file.bin")
 
 
 def test_binary_file_duplicate_equal():
     """Test writing same binary data to a file multiple times"""
-    expect_selfie(b"equal").to_be_file("duplicate_equal.bin")
-    expect_selfie(b"equal").to_be_file("duplicate_equal.bin")
-
-def test_binary_file_duplicate_unequal():
-    """Test writing same binary data to a file multiple times"""
-    try:
-        expect_selfie(b"a").to_be_file("duplicate_unequal.bin")
-        expect_selfie(b"b").to_be_file("duplicate_unequal.bin")
-    except AssertionError as e:
-        expect_selfie(str(e)).to_be("""Snapshot mismatch, TODO: string comparison
-- update this snapshot by adding `_TODO` to the function name
-- update all snapshots in this file by adding """)
+    expect_selfie(b"equal").to_be_file("tests/binary_test__test_binary_file_duplicate_equal.bin")
+    expect_selfie(b"equal").to_be_file("tests/binary_test__test_binary_file_duplicate_equal.bin")
 
 def test_binary_file_mismatch():
     """Test error handling for mismatched binary data"""
     with pytest.raises(AssertionError):
-        expect_selfie(b"different").to_be_file("test_binary.bin")
+        expect_selfie(b"different").to_be_file("tests/binary_test__SHOULD_NOT_EXIST.bin")
 
 
 def test_binary_file_not_found():
     """Test error handling for non-existent file"""
     with pytest.raises(AssertionError) as exc_info:
-        expect_selfie(b"test").to_be_file("nonexistent.bin")
+        expect_selfie(b"test").to_be_file("tests/binary_test__SHOULD_NOT_EXIST.bin")
     assert "no such file" in str(exc_info.value)
 
 
 def test_base64_mismatch():
     """Test error handling for mismatched base64 data"""
-    data = b"test data"
-    encoded = base64.b64encode(b"different data").decode()
-    with pytest.raises(AssertionError) as exc_info:
-        expect_selfie(data).to_be_base64("dGVzdCBkYXRh")
-    expect_selfie(str(exc_info.value)).to_be_TODO("Error while parsing the literal at File: /Users/ntwigg/Documents/dev/selfie/python/example-pytest-selfie/tests/binary_test.py, Line: 60. Please report this error at https://github.com/diffplug/selfie")
+    with pytest.raises(Exception) as exc_info:
+        expect_selfie(b"test data").to_be_base64("AAAA")
+    expect_selfie(str(exc_info.value)).to_be("""Snapshot mismatch, TODO: string comparison
+- update this snapshot by adding `_TODO` to the function name
+- update all snapshots in this file by adding `#selfieonce` or `#SELFIEWRITE`""")

python/example-pytest-selfie/tests/binary_test__test_binary_file.bin

@@ -0,0 +1 @@
+test binary data

python/example-pytest-selfie/tests/binary_test__test_binary_file_duplicate_equal.bin

@@ -0,0 +1 @@
+equal

python/example-pytest-selfie/tests/binary_test__test_binary_file_duplicate_unequal.bin

@@ -0,0 +1 @@
+a