Add "minRackVersion" plugin manifest property. Don't download plugin update if Rack version is lower than the plugin's minRackVersion.

include/library.hpp

@@ -13,6 +13,8 @@ struct UpdateInfo {
 	std::string name;
 	std::string version;
 	std::string changelogUrl;
+	/** Only defined if plugin does not meet Rack version requirement */
+	std::string minRackVersion;
 	bool downloaded = false;
 };
 

src/app/MenuBar.cpp

@@ -664,26 +664,37 @@ struct SyncUpdateItem : ui::MenuItem {
 			return NULL;
 		library::UpdateInfo update = it->second;
 
-		if (update.changelogUrl == "")
-			return NULL;
-
 		ui::Menu* menu = new ui::Menu;
 
-		std::string changelogUrl = update.changelogUrl;
-		menu->addChild(createMenuItem("Changelog", "", [=]() {
-			system::openBrowser(changelogUrl);
-		}));
+		if (update.minRackVersion != "") {
+			menu->addChild(createMenuLabel(string::f("Requires Rack %s+", update.minRackVersion.c_str())));
+		}
+
+		if (update.changelogUrl != "") {
+			std::string changelogUrl = update.changelogUrl;
+			menu->addChild(createMenuItem("Changelog", "", [=]() {
+				system::openBrowser(changelogUrl);
+			}));
+		}
 
+		if (menu->children.empty()) {
+			delete menu;
+			return NULL;
+		}
 		return menu;
 	}
 
 	void step() override {
-		disabled = library::isSyncing;
+		if (library::isSyncing)
+			disabled = true;
 
 		auto it = library::updateInfos.find(slug);
 		if (it != library::updateInfos.end()) {
 			library::UpdateInfo update = it->second;
 
+			if (update.minRackVersion != "")
+				disabled = true;
+
 			if (update.downloaded) {
 				rightText = CHECKMARK_STRING;
 				disabled = true;

src/library.cpp

@@ -12,6 +12,7 @@
 #include <asset.hpp>
 #include <settings.hpp>
 #include <plugin.hpp>
+#include <string.hpp>
 
 
 namespace rack {
@@ -278,6 +279,16 @@ void checkUpdates() {
 		if (changelogUrlJ)
 			update.changelogUrl = json_string_value(changelogUrlJ);
 
+		// Get minRackVersion
+		json_t* minRackVersionJ = json_object_get(manifestJ, "minRackVersion");
+		if (minRackVersionJ) {
+			std::string minRackVersion = json_string_value(minRackVersionJ);
+			// Check that Rack version is at least minRackVersion
+			if (string::Version(APP_VERSION) < string::Version(minRackVersion)) {
+				update.minRackVersion = minRackVersion;
+			}
+		}
+
 		// Add update to updates map
 		updateInfos[pluginSlug] = update;
 	}
@@ -349,6 +360,10 @@ void syncUpdate(std::string slug) {
 		return;
 	UpdateInfo update = it->second;
 
+	// Don't update if not compatible with Rack version
+	if (update.minRackVersion != "")
+		return;
+
 	updateSlug = slug;
 	DEFER({updateSlug = "";});