From d60b98b03739b615ec4b7f72da4ab9d7a21a1c9c Mon Sep 17 00:00:00 2001
From: Ofek Lev <ofekmeister@gmail.com>
Date: Wed, 10 Feb 2021 17:28:39 -0500
Subject: [PATCH] Add logical utility functions (#8590)

---
 .../base/checks/openmetrics/v2/labels.py      |  2 +-
 .../base/checks/openmetrics/v2/scraper.py     |  4 +--
 .../datadog_checks/base/utils/common.py       |  4 ---
 .../datadog_checks/base/utils/functions.py    | 31 +++++++++++++++++++
 4 files changed, 34 insertions(+), 7 deletions(-)
 create mode 100644 datadog_checks_base/datadog_checks/base/utils/functions.py

diff --git a/datadog_checks_base/datadog_checks/base/checks/openmetrics/v2/labels.py b/datadog_checks_base/datadog_checks/base/checks/openmetrics/v2/labels.py
index 50c4a75db4e31..22f150e9dbee3 100644
--- a/datadog_checks_base/datadog_checks/base/checks/openmetrics/v2/labels.py
+++ b/datadog_checks_base/datadog_checks/base/checks/openmetrics/v2/labels.py
@@ -1,7 +1,7 @@
 # (C) Datadog, Inc. 2020-present
 # All rights reserved
 # Licensed under a 3-clause BSD style license (see LICENSE)
-from ....utils.common import no_op
+from ....utils.functions import no_op
 
 
 class LabelAggregator:
diff --git a/datadog_checks_base/datadog_checks/base/checks/openmetrics/v2/scraper.py b/datadog_checks_base/datadog_checks/base/checks/openmetrics/v2/scraper.py
index eaa36afcf985e..5fd50e10f2c6f 100644
--- a/datadog_checks_base/datadog_checks/base/checks/openmetrics/v2/scraper.py
+++ b/datadog_checks_base/datadog_checks/base/checks/openmetrics/v2/scraper.py
@@ -15,7 +15,7 @@
 from ....config import is_affirmative
 from ....constants import ServiceCheck
 from ....errors import ConfigurationError
-from ....utils.common import no_op
+from ....utils.functions import no_op, return_true
 from ....utils.http import RequestsWrapper
 from .labels import LabelAggregator, get_label_normalizer
 from .transform import MetricTransformer
@@ -118,7 +118,7 @@ def __init__(self, check, config):
         elif exclude_metrics_by_labels:
             for label, values in exclude_metrics_by_labels.items():
                 if values is True:
-                    self.exclude_metrics_by_labels[label] = lambda label_value: True
+                    self.exclude_metrics_by_labels[label] = return_true
                 elif isinstance(values, list):
                     for i, value in enumerate(values, 1):
                         if not isinstance(value, str):
diff --git a/datadog_checks_base/datadog_checks/base/utils/common.py b/datadog_checks_base/datadog_checks/base/utils/common.py
index 9c5fce469012b..ef90b595afb65 100644
--- a/datadog_checks_base/datadog_checks/base/utils/common.py
+++ b/datadog_checks_base/datadog_checks/base/utils/common.py
@@ -38,10 +38,6 @@ def ensure_unicode(s):
 to_string = to_native_string
 
 
-def no_op(*args, **kwargs):
-    pass
-
-
 def compute_percent(part, total):
     if total:
         return part / total * 100
diff --git a/datadog_checks_base/datadog_checks/base/utils/functions.py b/datadog_checks_base/datadog_checks/base/utils/functions.py
new file mode 100644
index 0000000000000..1e441560afa0f
--- /dev/null
+++ b/datadog_checks_base/datadog_checks/base/utils/functions.py
@@ -0,0 +1,31 @@
+# (C) Datadog, Inc. 2021-present
+# All rights reserved
+# Licensed under a 3-clause BSD style license (see LICENSE)
+
+
+def identity(obj, **kwargs):
+    """
+    https://en.wikipedia.org/wiki/Identity_function
+    """
+    return obj
+
+
+def no_op(*args, **kwargs):
+    """
+    https://en.wikipedia.org/wiki/NOP_(code)
+    """
+
+
+def predicate(assertion):
+    """
+    https://en.wikipedia.org/wiki/Predicate_(mathematical_logic)
+    """
+    return return_true if bool(assertion) else return_false
+
+
+def return_true(*args, **kwargs):
+    return True
+
+
+def return_false(*args, **kwargs):
+    return False