From aa18575c835fdeff8ae4eb415b07d38e90fd332c Mon Sep 17 00:00:00 2001
From: Emmanuelle Vargas-Gonzalez <emmanuelle@mitre.org>
Date: Mon, 8 Jun 2020 09:27:12 -0400
Subject: [PATCH] add `id` as special-case option in regex. closes #406

---
 stix2/properties.py                      |  2 +-
 stix2/test/v20/test_granular_markings.py | 14 ++++++++++++++
 stix2/test/v21/test_granular_markings.py | 14 ++++++++++++++
 3 files changed, 29 insertions(+), 1 deletion(-)

diff --git a/stix2/properties.py b/stix2/properties.py
index c876c11..a267eb5 100644
--- a/stix2/properties.py
+++ b/stix2/properties.py
@@ -537,7 +537,7 @@ def enumerate_types(types, spec_version):
     return return_types
 
 
-SELECTOR_REGEX = re.compile(r"^[a-z0-9_-]{3,250}(\.(\[\d+\]|[a-z0-9_-]{1,250}))*$")
+SELECTOR_REGEX = re.compile(r"^([a-z0-9_-]{3,250}(\.(\[\d+\]|[a-z0-9_-]{1,250}))*|id)$")
 
 
 class SelectorProperty(Property):
diff --git a/stix2/test/v20/test_granular_markings.py b/stix2/test/v20/test_granular_markings.py
index e912cc1..ae2da3b 100644
--- a/stix2/test/v20/test_granular_markings.py
+++ b/stix2/test/v20/test_granular_markings.py
@@ -1089,3 +1089,17 @@ def test_clear_marking_not_present(data):
     """Test clearing markings for a selector that has no associated markings."""
     with pytest.raises(MarkingNotFoundError):
         data = markings.clear_markings(data, ["labels"])
+
+
+def test_set_marking_on_id_property():
+    malware = Malware(
+        granular_markings=[
+            {
+                "selectors": ["id"],
+                "marking_ref": MARKING_IDS[0],
+            },
+        ],
+        **MALWARE_KWARGS
+    )
+
+    assert "id" in malware["granular_markings"][0]["selectors"]
diff --git a/stix2/test/v21/test_granular_markings.py b/stix2/test/v21/test_granular_markings.py
index 1c3194b..ff8fe26 100644
--- a/stix2/test/v21/test_granular_markings.py
+++ b/stix2/test/v21/test_granular_markings.py
@@ -1307,3 +1307,17 @@ def test_clear_marking_not_present(data):
     """Test clearing markings for a selector that has no associated markings."""
     with pytest.raises(MarkingNotFoundError):
         markings.clear_markings(data, ["malware_types"])
+
+
+def test_set_marking_on_id_property():
+    malware = Malware(
+        granular_markings=[
+            {
+                "selectors": ["id"],
+                "marking_ref": MARKING_IDS[0],
+            },
+        ],
+        **MALWARE_KWARGS
+    )
+
+    assert "id" in malware["granular_markings"][0]["selectors"]