fix: retain the newest dictionary request

strans.c

@@ -135,7 +135,7 @@ reset(void)
 void
 dictsend(Im *im, Str *key)
 {
-	Dictreq req;
+	Dictreq old, req;
 
 	req.key = *key;
 	req.lang = im->l->lang;
@@ -143,6 +143,9 @@ dictsend(Im *im, Str *key)
 		jpreading(im, &req.pre);
 	else
 		req.pre = im->pre;
+	/* imthread is the sole producer; discard every obsolete queued lookup. */
+	while(channbrecv(dictreqc, &old) > 0)
+		;
 	channbsend(dictreqc, &req);
 }
 
@@ -271,7 +274,6 @@ static int
 dotrans(Rune c, Str *com)
 {
 	Emit e;
-	Dictreq req;
 	Str mapped;
 
 	if(isjp(&im))
@@ -297,10 +299,7 @@ dotrans(Rune c, Str *com)
 	sclear(&im.pre);
 	sappend(&im.pre, &e.next);
 	if(e.eat && e.dict.n > 0){
-		req.key = e.dict;
-		req.lang = im.l->lang;
-		req.pre = im.pre;
-		channbsend(dictreqc, &req);
+		dictsend(&im, &e.dict);
 	}
 	return e.eat;
 }
@@ -626,7 +625,7 @@ keystroke(u32int ks, u32int mod, Str *com)
 	off = 0;
 	if(im.sel >= Maxdisp)
 		off = im.sel - Maxdisp + 1;
-	if(n >= 0 && n < Maxdisp && off + n < im.nkouho){
+	if(n >= 0 && n < Maxdisp && off + n < im.nkouho && mod == 0){
 		sappend(com, &im.kouho[off + n]);
 		reset();
 		return 1;

tests/engine_test.c

@@ -108,6 +108,53 @@ engine_selects_visible_candidate(struct ct *t)
 	}
 }
 
+void
+engine_candidate_shortcut_modifiers(struct ct *t)
+{
+	static u32int mods[] = { Mctrl, Malt, Msuper };
+	Str com;
+	int i;
+
+	for(i = 0; i < nelem(mods); i++){
+		init();
+		im.kouho[0] = mkstr("must-not-select");
+		im.nkouho = 1;
+		im.sel = -1;
+		sclear(&com);
+		CT_CHECK(t, !keystroke('1', mods[i], &com));
+		CT_CHECK(t, scmp(&com, &im.kouho[0]) != 0);
+	}
+}
+
+void
+engine_dictionary_queue_latest_wins(struct ct *t)
+{
+	Channel *saved;
+	Dictreq old, got;
+	Str key;
+
+	saved = dictreqc;
+	dictreqc = chancreate(sizeof(Dictreq), 1);
+	memset(&old, 0, sizeof old);
+	old.key = mkstr("old-key");
+	old.pre = mkstr("old-preedit");
+	old.lang = LangJP;
+	CT_CHECK(t, channbsend(dictreqc, &old) > 0);
+	init();
+	im.l = getlang(LangJP);
+	im.pre = mkstr("new-preedit");
+	key = mkstr("new-key");
+	dictsend(&im, &key);
+	if(CT_CHECK(t, channbrecv(dictreqc, &got) > 0)){
+		checkstr(t, "newest dictionary key", "new-key", &got.key);
+		checkstr(t, "newest dictionary preedit", "new-preedit", &got.pre);
+		CT_EQ_INT(t, LangJP, got.lang);
+	}
+	CT_CHECK(t, channbrecv(dictreqc, &got) <= 0);
+	chanfree(dictreqc);
+	dictreqc = saved;
+}
+
 void
 engine_commit_contract(struct ct *t)
 {

tests/test.h

@@ -32,6 +32,8 @@ void	vietnamese_state_lifetime(struct ct*);
 void	engine_clears_candidates(struct ct*);
 void	engine_backspace_clears_candidates(struct ct*);
 void	engine_selects_visible_candidate(struct ct*);
+void	engine_candidate_shortcut_modifiers(struct ct*);
+void	engine_dictionary_queue_latest_wins(struct ct*);
 void	engine_commit_contract(struct ct*);
 void	engine_language_switch_state(struct ct*);
 void	engine_telex_history_bound(struct ct*);

tests/unit_test.c

@@ -81,6 +81,8 @@ static const struct ct_test tests[] = {
 	{ "engine/clears-candidates", engine_clears_candidates },
 	{ "engine/backspace-clears-candidates", engine_backspace_clears_candidates },
 	{ "engine/selects-visible-candidate", engine_selects_visible_candidate },
+	{ "engine/candidate-shortcut-modifiers", engine_candidate_shortcut_modifiers },
+	{ "engine/dictionary-queue-latest", engine_dictionary_queue_latest_wins },
 	{ "engine/commit-contract", engine_commit_contract },
 	{ "engine/language-switch-state", engine_language_switch_state },
 	{ "engine/telex-history-bound", engine_telex_history_bound },