fix: pass empty search backspace through

strans.c

@@ -620,8 +620,10 @@ searchkey(u32int ks, u32int mod, Str *com)
 		return 1;
 	}
 	if(ks == Kback){
-		if(search.raw.n == 0)
+		if(search.raw.n == 0){
-			return 1;
+			endsearch();
+			return 0;
+		}
 		spopr(&search.raw);
 		searchquery();
 		return 1;

tests/engine_test.c

@@ -1305,6 +1305,42 @@ engine_hanja_korean_keys(struct ct *t)
 	searchend(&f);
 }
 
+void
+engine_hanja_backspace(struct ct *t)
+{
+	Searchfix f;
+	Str com;
+
+	hanjabegin(&f, LangKO);
+	sclear(&com);
+	CT_CHECK(t, keystroke('h', Mctrl, &com));
+	if(!typekeys(t, "gks", &com))
+		goto cleanup;
+	checkstr(t, "Hanja before backspace", "한", &search.text);
+	CT_EQ_INT(t, 2, im.nkouho);
+	CT_CHECK(t, keystroke(Kback, 0, &com));
+	checkstr(t, "Hanja final backspace", "하", &search.text);
+	CT_EQ_INT(t, 0, im.nkouho);
+	CT_CHECK(t, keystroke(Kback, 0, &com));
+	checkstr(t, "Hanja vowel backspace", "ㅎ", &search.text);
+	CT_CHECK(t, keystroke(Kback, 0, &com));
+	checkstr(t, "empty Hanja search", "", &search.text);
+	CT_EQ_INT(t, LangHANJA, search.lang);
+	CT_CHECK(t, !keystroke(Kback, 0, &com));
+	CT_EQ_INT(t, 0, search.lang);
+
+	if(!typekeys(t, "gks", &com))
+		goto cleanup;
+	CT_CHECK(t, keystroke('h', Mctrl, &com));
+	checkstr(t, "preedit committed before Hanja", "한", &com);
+	CT_EQ_INT(t, LangHANJA, search.lang);
+	CT_CHECK(t, !keystroke(Kback, 0, &com));
+	CT_EQ_INT(t, 0, search.lang);
+	CT_EQ_INT(t, LangKO, im.l->lang);
+cleanup:
+	searchend(&f);
+}
+
 void
 engine_hanja_input_languages(struct ct *t)
 {

tests/test.h

@@ -57,6 +57,7 @@ void	engine_emoji_dictionary_identity(struct ct*);
 void	engine_hanja_search(struct ct*);
 void	engine_hanja_unknown_and_cancel(struct ct*);
 void	engine_hanja_korean_keys(struct ct*);
+void	engine_hanja_backspace(struct ct*);
 void	engine_hanja_input_languages(struct ct*);
 void	engine_randomized_stress(struct ct*);
 void	engine_full_boundary_passthrough(struct ct*);

tests/unit_test.c

@@ -111,6 +111,7 @@ static const struct ct_test tests[] = {
 	{ "engine/hanja-search", engine_hanja_search },
 	{ "engine/hanja-unknown-cancel", engine_hanja_unknown_and_cancel },
 	{ "engine/hanja-korean-keys", engine_hanja_korean_keys },
+	{ "engine/hanja-backspace", engine_hanja_backspace },
 	{ "engine/hanja-input-languages", engine_hanja_input_languages },
 	{ "engine/randomized-stress", engine_randomized_stress },
 	{ "engine/full-boundary-passthrough", engine_full_boundary_passthrough },