From 8e4aa62865226866e63df611b2e84c86bc357217 Mon Sep 17 00:00:00 2001
From: William Jamieson <wjamieson@stsci.edu>
Date: Thu, 16 Nov 2023 11:18:43 -0500
Subject: [PATCH] Add tests for dq flags.

---
 src/roman_datamodels/dqflags.py |  4 +-
 tests/test_dqflags.py           | 68 +++++++++++++++++++++++++++++++++
 2 files changed, 71 insertions(+), 1 deletion(-)
 create mode 100644 tests/test_dqflags.py

diff --git a/src/roman_datamodels/dqflags.py b/src/roman_datamodels/dqflags.py
index 5410c7ffc..9d4469954 100644
--- a/src/roman_datamodels/dqflags.py
+++ b/src/roman_datamodels/dqflags.py
@@ -18,10 +18,11 @@
 which provides 32 bits. Bits of an integer are most easily referred to using
 the formula `2**bit_number` where `bit_number` is the 0-index bit of interest.
 """
-from enum import IntEnum
+from enum import IntEnum, unique
 
 
 # fmt: off
+@unique
 class pixel(IntEnum):
     """Pixel-specific data quality flags"""
 
@@ -59,6 +60,7 @@ class pixel(IntEnum):
     REFERENCE_PIXEL  = 2**31  # Pixel is a reference pixel
 
 
+@unique
 class group(IntEnum):
     """Group-specific data quality flags
         Once groups are combined, these flags are equivalent to the pixel-specific flags.
diff --git a/tests/test_dqflags.py b/tests/test_dqflags.py
new file mode 100644
index 000000000..21b1a4405
--- /dev/null
+++ b/tests/test_dqflags.py
@@ -0,0 +1,68 @@
+from math import log10
+
+import pytest
+
+from roman_datamodels import dqflags
+
+
+def _is_power_of_two(x):
+    return (log10(x) / log10(2)) % 1 == 0
+
+
+def test_pixel_uniqueness():
+    """
+    Test that there are no duplicate names in dqflags.pixel
+
+        Note: The @unique decorator should ensure that no flag names have the
+            same value as another in the enum raising an error at first import
+            of this module. However, this test is just a sanity check on this.
+    """
+
+    assert len(dqflags.pixel) == len(dqflags.pixel.__members__)
+
+
+@pytest.mark.parametrize("flag", dqflags.pixel)
+def test_pixel_flags(flag):
+    """Test that each pixel flag follows the defined rules"""
+    # Test that the pixel flags are dqflags.pixel instances
+    assert isinstance(flag, dqflags.pixel)
+
+    # Test that the pixel flags are ints
+    assert isinstance(flag, int)
+
+    # Test that the pixel flags are dict accessible
+    assert dqflags.pixel[flag.name] is flag
+
+    # Test that the pixel flag is a power of 2
+    if flag.name == "GOOD":
+        # GOOD is the only non-power-of-two flag (it is 0)
+        assert flag.value == 0
+    else:
+        assert _is_power_of_two(flag.value)
+
+
+def test_group_uniqueness():
+    """
+    Test that there are no duplicate names in dqflags.group
+
+        Note: The @unique decorator should ensure that no flag names have the
+            same value as another in the enum raising an error at first import
+            of this module. However, this test is just a sanity check on this.
+    """
+    assert len(dqflags.group) == len(dqflags.group.__members__)
+
+
+@pytest.mark.parametrize("flag", dqflags.group)
+def test_group_flags(flag):
+    """Test that each group flag follows the defined rules"""
+    # Test that the group flags are dqflags.group instances
+    assert isinstance(flag, dqflags.group)
+
+    # Test that the group flags are ints
+    assert isinstance(flag, int)
+
+    # Test that the group flags are dict accessible
+    assert dqflags.group[flag.name] is flag
+
+    # Test that each group flag matches a pixel flag of the same name
+    assert dqflags.pixel[flag.name] == flag