'FileSystemService' is not a valid Service name

[westurner]

When I try to run jest-lua in Roblox Studio, I get the following error message:

getDataModelService:4: 'FileSystemService' is not a valid Service name

• I have FFlagEnableLoadModule set to true (Add documentation for flag flipping #6 (comment)
• I could finish patching run-in-roblox to work on linux,
  but all I want to do is run the tests at init if in Roblox Studio.
  • run-in-roblox runs tests on a Place in Roblox Studio and captures the test output
  • Would that solve for this issue though, because run-in-roblox just runs in regular Roblox Studio fwiu?

[westurner]

• Here's the test runner I'm attempting to call from within Roblox Studio:

-- Run jest tests
-- src: https://jsdotlua.github.io/jest-lua/ : MIT
function main_test()

	local ReplicatedStorage = game:GetService("ReplicatedStorage")

	--local runCLI = require("@DevPackages/Jest").runCLI
	local runCLI = require(ReplicatedStorage.DevPackages.Jest).runCLI
	
	local processServiceExists, ProcessService = pcall(function()
		return game:GetService("ProcessService")
	end)

	local StarterPlayer = game:GetService("StarterPlayer")
	local clientTests = StarterPlayer.StarterPlayerScripts
	
	local status, result = runCLI(clientTests, {
		verbose = false,
		ci = false
	}, { clientTests }):awaitStatus()
	
	if status == "Rejected" then
		print(result)
	end
	
	if status == "Resolved" and result.results.numFailedTestSuites == 0 and result.results.numFailedTests == 0 then
		if processServiceExists then
			ProcessService:ExitAsync(0)
		end
	end
	
	if processServiceExists then
		ProcessService:ExitAsync(1)
	end
	
	return nil
end

if game:GetService("RunService").IsStudio then
	print("INFO: AreaVolumeCube.client: main_test() starting ...")
	main_test()
	print("INFO: AreaVolumeCube.client: main_test() complete.")
else
	print("INFO: AreaVolumeCube.client: Skipping main_test() because .IsStudio is false")
end

return exports

[westurner]

• /? "FileSystemService" roblox
  https://www.google.com/search?q=%22FileSystemService%22+roblox
  • Support implementing new Roblox services lune-org/lune#125
  • https://github.com/Roblox/jest-roblox/blob/master/CHANGELOG.md
    • 2021: "🐛 Fix for JestSnapshot throwing in environments where FileSystemService does not exist (#103)"
  • https://github.com/jsdotlua/jest-lua/blob/main/src/jest-snapshot/README.md

    Major deviations on snapshot read/write implementation details because we handle reading snapshots through various Roblox-specific mechanisms like ModuleScript, FileSystemService, and CoreScriptSyncService.

What is FileSystemService and why do I need one for snapshots, to run the tests at init?

Can a mock FileSystemService that writes to an in-RAM FS work for jest, at least?

• Support implementing new Roblox services lune-org/lune#125

Are there additional errors after getDataModelService:4: 'FileSystemService' is not a valid Service name?

[westurner]

• lune has fs.:
  https://lune.gitbook.io/lune/api-reference/fs
• lemur has fs.:
  https://github.com/LPGhatguy/lemur/blob/master/lib/fs.lua
• https://github.com/LPGhatguy/lemur/blob/master/FEATURES.md#implemented-services
• lemur (MIT) has RunService but not FileSystemService
  https://github.com/LPGhatguy/lemur/blob/master/lib/instances/RunService.lua
• https://github.com/LPGhatguy/lemur/pull/146/files
• https://github.com/LPGhatguy/lemur/pull/185/files
  • this is probably how to add a FileSystemService to lemur

[westurner]

FileSystemService probably just works in Open Cloud Engine API, which basically takes --place and --script like run-in-roblox?

• https://devforum.roblox.com/t/beta-open-cloud-engine-api-for-executing-luau/3172185
• https://create.roblox.com/docs/cloud/features/luau-execution
• https://create.roblox.com/docs/cloud/reference/LuauExecutionSessionTask

[westurner]

• /? run-in-roblox path:.github/workflows/*.yml
  https://github.com/search?q=run-in-roblox+path%3A.github%2Fworkflows%2F*.yml&type=code
  • https://github.com/Dionysusnu/Fusion/blob/eaa4fc830dc92bdd3c769be16a107950709d05f1/.github/workflows/ci.yml#L62
  • https://github.com/ok-nick/LayoutUtil/blob/master/.github/workflows/check.yml#L41
• https://github.com/Roblox/place-ci-cd-demo/blob/production/.github/workflows/cicd.yml (archived)
  • https://github.com/Roblox/place-ci-cd-demo/blob/11c635a02bbbc0fc969c87e1fa433e27286ed392/.github/workflows/cicd.yml#L71
  • https://github.com/Roblox/place-ci-cd-demo/blob/production/scripts/shell/test.sh