Verification: move disabled DM handling into helper

Note that we were previously only catching 403. As the docstring
explains, we will now catch any Discord exception and only look
at the the code, rather than the status.

1 files changed, 22 insertions, 5 deletions

diff --git a/bot/exts/moderation/verification.py b/bot/exts/moderation/verification.py
index e9ab2c816..e10ad3e23 100644
--- a/bot/exts/moderation/verification.py
+++ b/bot/exts/moderation/verification.py
@@ -109,6 +109,25 @@ def is_verified(member: discord.Member) -> bool:
     return len(set(member.roles) - unverified_roles) > 0
 
 
+async def safe_dm(coro: t.Coroutine) -> None:
+    """
+    Execute `coro` ignoring disabled DM warnings.
+
+    The 50_0007 error code indicates that the target user does not accept DMs.
+    As it turns out, this error code can appear on both 400 and 403 statuses,
+    we therefore catch any Discord exception.
+
+    If the request fails on any other error code, the exception propagates,
+    and must be handled by the caller.
+    """
+    try:
+        await coro
+    except discord.HTTPException as discord_exc:
+        log.trace(f"DM dispatch failed on status {discord_exc.status} with code: {discord_exc.code}")
+        if discord_exc.code != 50_007:  # If any reason other than disabled DMs
+            raise
+
+
 class Verification(Cog):
     """
     User verification and role management.
@@ -330,11 +349,9 @@ class Verification(Cog):
         async def kick_request(member: discord.Member) -> None:
             """Send `KICKED_MESSAGE` to `member` and kick them from the guild."""
             try:
-                await member.send(KICKED_MESSAGE)
-            except discord.Forbidden as exc_403:
-                log.trace(f"DM dispatch failed on 403 error with code: {exc_403.code}")
-                if exc_403.code != 50_007:  # 403 raised for any other reason than disabled DMs
-                    raise StopExecution(reason=exc_403)
+                await safe_dm(member.send(KICKED_MESSAGE))  # Suppress disabled DMs
+            except discord.HTTPException as suspicious_exception:
+                raise StopExecution(reason=suspicious_exception)
             await member.kick(reason=f"User has not verified in {constants.Verification.kicked_after} days")
 
         n_kicked = await self._send_requests(members, kick_request, Limit(batch_size=2, sleep_secs=1))