Show informative empty posts search.

Telegram/SourceFiles/dialogs/dialogs_search_posts.cpp

@@ -117,7 +117,9 @@ void PostsSearch::pushStateUpdate(const Entry &entry) {
 		}
 		return;
 	}
-	if (!entry.pages.empty() || entry.loaded) {
+	const auto empty = entry.pages.empty()
+		|| (entry.pages.size() == 1 && entry.pages.front().empty());
+	if (!empty || (entry.loaded && !_query->isEmpty())) {
 		if (!entry.pages.empty()) {
 			++entry.pagesPushed;
 		}

Telegram/SourceFiles/dialogs/ui/dialogs_suggestions.cpp

@@ -2020,6 +2020,10 @@ void Suggestions::setupPostsIntro(const PostsSearchIntroState &intro) {
 		}
 	}, _postsSearchIntro->lifetime());
 
+	_postsScroll->heightValue() | rpl::start_with_next([=](int height) {
+		_postsWrap->resize(_postsWrap->width(), height);
+	}, _postsSearchIntro->lifetime());
+
 	_postsSearchIntro->show();
 	updateControlsGeometry();
 }

Telegram/SourceFiles/dialogs/ui/posts_search_intro.cpp

@@ -198,6 +198,12 @@ void PostsSearchIntro::setup() {
 
 	_state.value(
 	) | rpl::start_with_next([=](const PostsSearchIntroState &state) {
+		if (state.query.trimmed().isEmpty()) {
+			_button->resize(_button->width(), 0);
+			_content->resizeToWidth(width());
+			return;
+		}
+
 		auto copy = _button->children();
 		for (const auto child : copy) {
 			delete child;
@@ -232,6 +238,7 @@ void PostsSearchIntro::setup() {
 				st::resaleButtonTitle,
 				st::resaleButtonSubtitle);
 		}
+		_button->resize(_button->width(), st::postsSearchIntroButton.height);
 		_content->resizeToWidth(width());
 	}, _button->lifetime());
 }