fix bogus orphaning due to expunging

we cannot orphan all messages whose opposite we expunge, as that would
prevent subsequent propagation of the deletion. we can do that only if
the message is already known to be marked as deleted.

src/run-tests.pl

@@ -1064,6 +1064,26 @@ my @X08 = (
 );
 test("push flags + pull deletions", \@x01, \@X08, \@O08);
 
+my @O09 = ("", "", "Sync None\nExpunge Both\n");
+my @X09 = (
+  I, 0, I,
+  E, "/", "", "",
+  F, "", "", "/",
+  H, "/", "", "",
+  J, "/", "", "",
+  L, "", "", "/",
+);
+test("noop + expunge both", \@x01, \@X09, \@O09);
+
+my @O0A = ("", "", "Sync None\nExpunge Near\n");
+# Sync entries are not updated/pruned, because the far side is not loaded.
+my @X0A = (
+  I, 0, I,
+  F, "", "", "/",
+  L, "", "", "/",
+);
+test("noop + expunge near side", \@x01, \@X0A, \@O0A);
+
 # Size restriction tests
 
 my @x20 = (

src/sync.c

@@ -1812,11 +1812,11 @@ box_closed_p2( sync_vars_t *svars, int t )
 				    ((srec->status & S_EXPIRED) && svars->maxuid[F] >= srec->uid[F] && svars->maxxfuid >= srec->uid[F])) {
 					PC_JLOG( "- %u %u", (srec->uid[F], srec->uid[N]), "killing" );
 					srec->status = S_DEAD;
-				} else if (srec->uid[N]) {
+				} else if (srec->uid[N] && (srec->status & S_DEL(F))) {
 					PC_JLOG( "> %u %u 0", (srec->uid[F], srec->uid[N]), "orphaning" );
 					srec->uid[N] = 0;
 				}
-			} else if (srec->uid[F] && ((srec->status & S_DEL(F)) && (svars->state[F] & ST_DID_EXPUNGE))) {
+			} else if (srec->uid[F] && ((srec->status & S_DEL(F)) && (svars->state[F] & ST_DID_EXPUNGE)) && (srec->status & S_DEL(N))) {
 				PC_JLOG( "< %u %u 0", (srec->uid[F], srec->uid[N]), "orphaning" );
 				srec->uid[F] = 0;
 			}