python
diff --git a/‎bedevere/util.py
Lines changed: 33 additions & 1 deletion b/‎bedevere/util.py
Lines changed: 33 additions & 1 deletion
diff --git a/‎tests/test_gh_issue.py
Lines changed: 24 additions & 4 deletions b/‎tests/test_gh_issue.py
Lines changed: 24 additions & 4 deletions
@@ -3,7 +3,18 @@
 
 import gidgethub
 
+
+DEFAULT_BODY = ""
+TAG_NAME = "gh-issue-number"
 NEWS_NEXT_DIR = "Misc/NEWS.d/next/"
+CLOSING_TAG = f"<!-- /{TAG_NAME} -->"
+BODY = f"""\
+{{body}}
+
+<!-- {TAG_NAME}: gh-{{issue_number}} -->
+* gh-{{issue_number}}
+{CLOSING_TAG}
+"""
 
 
 @enum.unique
@@ -67,7 +78,10 @@ async def files_for_PR(gh, pull_request):
     data = []
     async for filedata in gh.getiter(files_url):  # pragma: no branch
         data.append(
-            {"file_name": filedata["filename"], "patch": filedata.get("patch", ""),}
+            {
+                "file_name": filedata["filename"],
+                "patch": filedata.get("patch", ""),
+            }
         )
     return data
 
@@ -77,6 +91,24 @@ async def issue_for_PR(gh, pull_request):
     return await gh.getitem(pull_request["issue_url"])
 
 
+async def patch_body(gh, pull_request, issue_number):
+    """Updates the description of a PR with the gh issue number if it exists.
+
+    returns if body exists with issue_number
+    """
+    if "body" not in pull_request or pull_request["body"] is None:
+        return await gh.patch(
+            pull_request["url"],
+            data=BODY.format(body=DEFAULT_BODY, issue_number=issue_number),
+        )
+    if f"GH-{issue_number}\n" not in pull_request["body"]:
+        return await gh.patch(
+            pull_request["url"],
+            data=BODY.format(body=pull_request["body"], issue_number=issue_number),
+        )
+    return
+
+
 async def is_core_dev(gh, username):
     """Check if the user is a CPython core developer."""
     org_teams = "/orgs/python/teams"
 
@@ -12,11 +12,14 @@
 
 class FakeGH:
 
-    def __init__(self, *, getitem=None, post=None):
+    def __init__(self, *, getitem=None, post=None, patch=None):
         self._getitem_return = getitem
         self._post_return = post
+        self._patch_return = patch
         self.post_url = []
         self.post_data = []
+        self.patch_url = []
+        self.patch_data = []
 
     async def getitem(self, url):
         if isinstance(self._getitem_return, Exception):
@@ -28,7 +31,6 @@ async def post(self, url, *, data):
         self.post_data.append(data)
         return self._post_return
 
-
 @pytest.mark.asyncio
 @pytest.mark.parametrize("action", ["opened", "synchronize", "reopened"])
 async def test_set_status_failure(action, monkeypatch):
@@ -40,6 +42,7 @@ async def test_set_status_failure(action, monkeypatch):
             "statuses_url": "https://api.github.com/blah/blah/git-sha",
             "title": "No issue in title",
             "issue_url": "issue URL",
+            "url": "url",
         },
     }
     issue_data = {
@@ -68,6 +71,8 @@ async def test_set_status_failure_via_issue_not_found_on_github(action, monkeypa
         "pull_request": {
              "statuses_url": "https://api.github.com/blah/blah/git-sha",
             "title": "gh-123: Invalid issue number",
+            "issue_url": "issue URL",
+            "url": "url",
         },
     }
     event = sansio.Event(data, event="pull_request", delivery_id="12345")
@@ -88,7 +93,9 @@ async def test_set_status_success_issue_found_on_bpo(action):
         "action": action,
         "pull_request": {
             "statuses_url": "https://api.github.com/blah/blah/git-sha",
-            "title": "bpo-12345: an issue!",
+            "title": "bpo-12345: An issue on b.p.o",
+            "issue_url": "issue URL",
+            "url": "url",
         },
     }
     event = sansio.Event(data, event="pull_request", delivery_id="12345")
@@ -112,6 +119,7 @@ async def test_set_status_success(action, monkeypatch):
         "action": action,
         "pull_request": {
             "statuses_url": "https://api.github.com/blah/blah/git-sha",
+            "url": "",
             "title": "[3.6] gh-1234: an issue!",
         },
     }
@@ -137,6 +145,7 @@ async def test_set_status_success_issue_found_on_gh(action, monkeypatch):
         "pull_request": {
             "statuses_url": "https://api.github.com/blah/blah/git-sha",
             "title": "gh-12345: an issue!",
+            "url": "url",
         },
     }
     event = sansio.Event(data, event="pull_request", delivery_id="12345")
@@ -161,6 +170,7 @@ async def test_set_status_success_issue_found_on_gh_ignore_case(action, monkeypa
         "pull_request": {
             "statuses_url": "https://api.github.com/blah/blah/git-sha",
             "title": "GH-12345: an issue!",
+            "url": "url",
         },
     }
     event = sansio.Event(data, event="pull_request", delivery_id="12345")
@@ -186,6 +196,7 @@ async def test_set_status_success_via_skip_issue_label(action, monkeypatch):
             "statuses_url": "https://api.github.com/blah/blah/git-sha",
             "title": "No issue in title",
             "issue_url": "issue URL",
+            "url": "url",
         },
     }
     issue_data = {
@@ -211,6 +222,7 @@ async def test_edit_title(monkeypatch):
         "pull_request": {
             "statuses_url": "https://api.github.com/blah/blah/git-sha",
             "title": "gh-1234: an issue!",
+            "url": "url",
         },
         "action": "edited",
         "changes": {"title": "thingy"},
@@ -251,6 +263,7 @@ async def test_edit_other_than_title(monkeypatch):
         "pull_request": {
             "statuses_url": "https://api.github.com/blah/blah/git-sha",
             "title": "bpo-1234: an issue!",
+            "url": "url",
         },
         "action": "edited",
         "changes": {"stuff": "thingy"},
@@ -270,6 +283,7 @@ async def test_new_label_skip_issue_no_issue():
         "pull_request": {
             "statuses_url": "https://api.github.com/blah/blah/git-sha",
             "title": "An easy fix",
+            "url": "url",
         },
     }
     event = sansio.Event(data, event="pull_request", delivery_id="12345")
@@ -287,6 +301,7 @@ async def test_new_label_skip_issue_with_issue_number():
         "pull_request": {
             "statuses_url": "https://api.github.com/blah/blah/git-sha",
             "title": "Revert gh-1234: revert an easy fix",
+            "url": "url",
         },
     }
     event = sansio.Event(data, event="pull_request", delivery_id="12345")
@@ -308,6 +323,7 @@ async def test_new_label_skip_issue_with_issue_number_ignore_case():
         "pull_request": {
             "statuses_url": "https://api.github.com/blah/blah/git-sha",
             "title": "Revert Gh-1234: revert an easy fix",
+            "url": "url",
         },
     }
     event = sansio.Event(data, event="pull_request", delivery_id="12345")
@@ -327,6 +343,7 @@ async def test_new_label_not_skip_issue():
         "label": {"name": "non-trivial"},
         "pull_request": {
             "statuses_url": "https://api.github.com/blah/blah/git-sha",
+            "url": "url",
         },
     }
     event = sansio.Event(data, event="pull_request", delivery_id="12345")
@@ -347,6 +364,7 @@ async def test_removed_label_from_label_deletion(monkeypatch):
         "pull_request": {
             "statuses_url": "https://api.github.com/blah/blah/git-sha",
             "title": "gh-1234: an issue!",
+            "url": "url",
         },
     }
     event = sansio.Event(data, event="pull_request", delivery_id="12345")
@@ -366,6 +384,7 @@ async def test_removed_label_skip_issue(monkeypatch):
         "pull_request": {
             "statuses_url": "https://api.github.com/blah/blah/git-sha",
             "title": "gh-1234: an issue!",
+            "url": "url",
         },
     }
     event = sansio.Event(data, event="pull_request", delivery_id="12345")
@@ -389,6 +408,7 @@ async def test_removed_label_non_skip_issue(monkeypatch):
         "label": {"name": "non-trivial"},
         "pull_request": {
             "statuses_url": "https://api.github.com/blah/blah/git-sha",
+            "url": "url",
         },
     }
     event = sansio.Event(data, event="pull_request", delivery_id="12345")
@@ -422,7 +442,7 @@ async def test_validate_issue_number_is_pr_on_github():
 
     gh = FakeGH(getitem={
         "number": 123,
-        "pull_request": {"html_url": "https://github.com/python/cpython/pull/123"}
+        "pull_request": {"html_url": "https://github.com/python/cpython/pull/123", "url": "url",}
     })
     async with aiohttp.ClientSession() as session:
         response = await gh_issue._validate_issue_number(gh, 123, session=session)