add gs

RCCService2021/ExtraContent/LuaPackages/AppTempCommon/LuaApp/PromiseUtilities.lua

@@ -0,0 +1,91 @@
+--[[
+	Provides utility functions for Promises
+]]
+
+local CorePackages = game:GetService("CorePackages")
+
+local Result = require(CorePackages.AppTempCommon.LuaApp.Result)
+local Promise = require(CorePackages.AppTempCommon.LuaApp.Promise)
+
+local PromiseUtilities = {}
+
+--[[
+	Accept a table of promises;
+		promises = {
+			[1] = Promise.resolve(),
+			["Home"] = Promise.reject(),
+			...
+		}
+	Returns a new promise that:
+		* is resolved when all input promises are finished.
+			returns the results of each individual promises in a list of Results
+				results = {
+					[1] = Result1,
+					["Home"] = Result2,
+					...
+				}
+		* is never rejected.
+]]
+function PromiseUtilities.Batch(promises)
+	assert(type(promises) == "table", "PromiseUtilities expects a list of Promises!")
+
+	local numberOfPromises = 0
+
+	for _, promise in pairs(promises) do
+		assert(Promise.is(promise), "PromiseUtilities expects a list of Promises!")
+		numberOfPromises = numberOfPromises + 1
+	end
+
+	return Promise.new(function(resolve, reject)
+		local totalCompleted = 0
+		local results = {}
+
+		local function promiseCompleted(key, success, value)
+			results[key] = Result.new(success, value)
+			totalCompleted = totalCompleted + 1
+
+			if totalCompleted == numberOfPromises then
+				resolve(results)
+			end
+		end
+
+		if next(promises) == nil then
+			resolve(results)
+		end
+
+		for key, promise in pairs(promises) do
+			promise:andThen(
+				function(result, ...)
+					if select("#", ...) > 0 then
+						warn("Promises in PromiseUtilities.Batch should not return tuple")
+					end
+					promiseCompleted(key, true, result)
+				end,
+				function(reason)
+					promiseCompleted(key, false, reason)
+				end
+			)
+		end
+	end)
+end
+
+function PromiseUtilities.CountResults(batchPromiseResults)
+	local totalCount = 0
+	local failureCount = 0
+
+	for _, result in pairs(batchPromiseResults) do
+		local success, _ = result:unwrap()
+		if not success then
+			failureCount = failureCount + 1
+		end
+		totalCount = totalCount + 1
+	end
+
+	return {
+		successCount = totalCount - failureCount,
+		failureCount = failureCount,
+		totalCount = totalCount,
+	}
+end
+
+return PromiseUtilities