fix: assign one active engine owner

tests/engine_test.c

@@ -155,6 +155,75 @@ engine_dictionary_queue_latest_wins(struct ct *t)
 	dictreqc = saved;
 }
 
+static Keyres
+ownerrequest(uvlong owner, int op, Rune key, u32int mod)
+{
+	Channel *reply;
+	Keyreq req;
+	Keyres res;
+
+	reply = chancreate(sizeof(Keyres), 1);
+	memset(&req, 0, sizeof req);
+	req.owner = owner;
+	req.op = op;
+	req.ks = key;
+	req.mod = mod;
+	req.want = 1;
+	req.reply = reply;
+	imhandlekey(&req);
+	chanrecv(reply, &res);
+	chanfree(reply);
+	return res;
+}
+
+void
+engine_active_owner_lifecycle(struct ct *t)
+{
+	Keyres res;
+	Str shown;
+	uvlong a, b, c;
+
+	a = ownernew();
+	b = ownernew();
+	c = ownernew();
+	CT_CHECK(t, a != 0 && b != 0 && c != 0);
+	CT_CHECK(t, a != b && b != c && a != c);
+	init();
+	im.l = getlang(LangJP);
+	res = ownerrequest(a, Keypress, 'k', 0);
+	CT_CHECK(t, res.eaten);
+	res = ownerrequest(a, Keypress, 'a', 0);
+	checkstr(t, "first owner preedit", "か", &res.preedit);
+	CT_EQ_UINT(t, a, activeowner);
+
+	res = ownerrequest(b, Keypress, 'n', 0);
+	checkstr(t, "takeover resets old preedit", "ん", &res.preedit);
+	CT_EQ_UINT(t, b, activeowner);
+	res = ownerrequest(a, Keyreset, 0, 0);
+	CT_EQ_INT(t, 0, res.preedit.n);
+	shown = shownpre(&im);
+	checkstr(t, "stale reset preserves owner", "ん", &shown);
+	CT_EQ_UINT(t, b, activeowner);
+
+	res = ownerrequest(b, Keypress, 'y', 0);
+	res = ownerrequest(b, Keypress, 'a', 0);
+	checkstr(t, "current owner continues", "にゃ", &res.preedit);
+	ownerrequest(a, Keyrelease, 0, 0);
+	shown = shownpre(&im);
+	checkstr(t, "stale release preserves owner", "にゃ", &shown);
+	CT_EQ_UINT(t, b, activeowner);
+
+	ownerrequest(b, Keyrelease, 0, 0);
+	CT_EQ_UINT(t, 0, activeowner);
+	CT_EQ_INT(t, 0, im.pre.n);
+	CT_EQ_INT(t, 0, im.raw.n);
+	ownerrequest(c, Keypress, Kmodfirst, 0);
+	CT_EQ_UINT(t, 0, activeowner);
+	res = ownerrequest(c, Keypress, 'k', 0);
+	CT_EQ_UINT(t, c, activeowner);
+	checkstr(t, "next owner first key", "k", &res.preedit);
+}
+
 void
 engine_commit_contract(struct ct *t)
 {