I’ve noticed Codex often struggles to run tests in an umbrella app. It repeatedly follows a long trial-and-error process before eventually succeeding. Could anyone help me figure out why this happens and how to make it run the tests correctly on the first try? Below is the process it goes through:
• Ran cd /Users/john/Developer/Demo/demo_server && MIX_ENV=test mix test apps/foo_app/test└ \*\* (RuntimeError) failed to start Mix.PubSub, reason: {{:shutdown, {:failed_to_start_child, Mix.PubSub.Subscriber, {%Mix.Error{message: “failed to open a TCP socket in Mix.Sync.PubSub.subscribe/1, reason: :eperm”, mix: 1}, \[{Mix, :raise,2, \[file: \~c"lib/mix.ex", line: 647\]}, {Mix.PubSub.Subscriber, :init, 1, \[file: \~c"lib/mix/pubsub/subscriber.ex", line: 24\]}, {:gen_server, :init_it, 2, \[file: \~c"gen_server.erl", line: 2276\]}, {:gen_server, :init_it, 6, \[file:… +8 lines(mix 1.19.4) lib/mix/task.ex:474: Mix.Task.maybe_load_or_compile_task/2(mix 1.19.4) lib/mix/task.ex:428: Mix.Task.do_run/3
• I’m considering how Mix.PubSub doesn’t start for mix run—it might not be needed. Yet, the stack shows it starting in deps.loadpaths. Maybe mix run follows a different code path that skips PubSub? There’s also the possibility that an errorhappens when trying to open a restricted port. This could be a non-deterministic issue depending on the port number used. If the environment prohibits opening sockets selectively, that could be my issue. The error code :eperm suggests apermission problem, not an address conflict.
Investigating Mix Test Issues
I’m thinking that maybe mix test is starting more processes or using a code reloader that requires watchers needing TCP. Mix.PubSub is linked with Mix.Sync, which handles concurrency across multiple tasks and uses local TCP with 127.0.0.1.In some sandbox environments, opening TCP sockets might be restricted. I’m curious why mix run succeeded, though. Maybe it didn’t start Mix.Sync PubSub because subscribing wasn’t necessary, possibly due to MIX_EXS. I’ll need to dive deeperinto the versions and how Mix.Tasks.Run operates!
Analyzing Environment Changes
I’m pondering if something changed in the environment between commands. Earlier, I ran MIX_ENV=test mix run scripts/perf/explain_foo.exs, possibly with pre-compiled tasks. Yet, each exec_command runs as a separate process. I wonder ifmix test and mix run both using MIX_ENV=test might be the issue. There’s an error regarding opening a TCP socket in Mix.Sync.PubSub, potentially due to MIX_SYNC. Opening TCP might be blocked at the OS level, but why did mix run succeed?Maybe it didn’t trigger the PubSub code since dependencies were already loaded.
Testing with Mix Help
I’m considering that mix still calls deps.loadpaths, but if dependencies are already compiled and cached, maybe it doesn’t start PubSub. I want to test this further. I could run mix help or any mix task to see if the error reoccurs. If ithappens consistently, I might need a workaround. So, I’ll go ahead and run mix help to check for errors—got to make sure it’s an approved command first, which it is!
• Ran cd /Users/john/Developer/Demo/demo_server && mix help└ mix # Runs the default task (current: “mix run”)mix absinthe.plug.graphiql.assets.download # Download GraphiQL assets… +106 lines
Use “mix help ” for more information on a particular command.
• Ran cd /Users/john/Developer/Demo/demo_server && MIX_ENV=test mix help└ \*\* (RuntimeError) failed to start Mix.PubSub, reason: {{:shutdown, {:failed_to_start_child, Mix.PubSub.Subscriber, {%Mix.Error{message: “failed to open a TCP socket in Mix.Sync.PubSub.subscribe/1, reason: :eperm”, mix: 1}, \[{Mix, :raise,2, \[file: \~c"lib/mix.ex", line: 647\]}, {Mix.PubSub.Subscriber, :init, 1, \[file: \~c"lib/mix/pubsub/subscriber.ex", line: 24\]}, {:gen_server, :init_it, 2, \[file: \~c"gen_server.erl", line: 2276\]}, {:gen_server, :init_it, 6, \[file:… +8 lines(mix 1.19.4) lib/mix/tasks/help.ex:59: Mix.Tasks.Help.run/1(mix 1.19.4) lib/mix/task.ex:499: anonymous fn/3 in Mix.Task.run_task/5
• I’m noticing that when the MIX_ENV=test is set, there’s a failure related to opening a Mix.PubSub socket due to an eperm error. Interestingly, the same environment worked previously when running a specific script. I need to think about whymix help would suddenly fail now. Maybe Mix.PubSub was able to use an ephemeral port before, but something has changed, leading to permission issues. I need to explore that further!
Exploring script execution issues
I’m considering that when running the script with MIX_ENV=test, it might have used a cached environment and didn’t start PubSub because Mix was already active. However, that seems unlikely since each command should run in a new process.Oh, but we did execute the command with MIX_ENV=test in front of it, and that succeeded. It’s puzzling why mix help fails now. Maybe it’s related to environment variables or recent changes in file watchers. The error regarding TCP socketin Mix.Sync.PubSub is curious too!
Analyzing execution environment
I’m thinking that the prefix approval rule might be using /bin/zsh -lc to run that command, potentially bypassing restrictions. Wait, do we really run exec_command inside a sandbox with a zsh login shell? It seems it could run the commandthrough the default shell. I wonder if it executes with the login option set to true, specifically with Mix running in the test environment. The difference could be linked to port binding with MIX_SYNC_PORT—maybe it succeeded before but isnow hitting an OS limit for open ports?
Testing for eperm failure
I’m considering that the eperm failure might be due to a file descriptor creation attempt within some sandbox, but that seems unlikely. Still, I’ll try to replicate the issue by rerunning the command MIX_ENV=test mix run -e ‘IO.puts(“hi”)’to see if it fails again. This could help me understand whether the problem is consistent or if it’s just an intermittent issue with the environment!
• Ran cd /Users/john/Developer/Demo/demo_server && MIX_ENV=test mix run -e ‘IO.puts(“hi”)’└ \*\* (RuntimeError) failed to start Mix.PubSub, reason: {{:shutdown, {:failed_to_start_child, Mix.PubSub.Subscriber, {%Mix.Error{message: “failed to open a TCP socket in Mix.Sync.PubSub.subscribe/1, reason: :eperm”, mix: 1}, \[{Mix, :raise,2, \[file: \~c"lib/mix.ex", line: 647\]}, {Mix.PubSub.Subscriber, :init, 1, \[file: \~c"lib/mix/pubsub/subscriber.ex", line: 24\]}, {:gen_server, :init_it, 2, \[file: \~c"gen_server.erl", line: 2276\]}, {:gen_server, :init_it, 6, \[file:… +8 lines(mix 1.19.4) lib/mix/task.ex:499: anonymous fn/3 in Mix.Task.run_task/5(mix 1.19.4) lib/mix/tasks/app.config.ex:33: Mix.Tasks.App.Config.run/1
• I’m thinking that running mix test might compile the test configuration. When I use mix test, it sets the environment to :test, but I need to double-check if it still does that if MIX_ENV isn’t set.
I wonder if running MIX_ENV=prod mix test would actually execute tests in the production environment, which isn’t typical. It might be worth exploring mix env to clarify which environment is currently set. I also recall that Mix.env iscompile-time, but tasks could potentially use it.
Exploring Mix.Sync.PubSub configuration
I’m considering setting the environment variable MIX_SYNC_PUBSUB_PORT=0. I want to check the Mix.Sync.PubSub documentation quickly, but without internet access, my next best option might be to look at the source code in the Elixirinstallation, specifically lib/mix/sync/pubsub.ex.
I could use elixir -e to find some useful info without needing Mix. However, I think there could be restrictions in the sandbox environment that would block opening a TCP socket, which Mix.Sync requires for file system watchers. DisablingMix.Sync by setting MIX_SYNC might be the way to go.
Investigating Mix.Sync.PubSub
I’m thinking about searching through the Mix code for MIX_SYNC_PUBSUB using rg in my local Elixir installation. I could look in the \_build or use a command like rg “Mix.Sync.PubSub”.
Since I’m in a sandbox environment, network operations might be restricted. The new “mix sync” feature introduced in Mix 1.19 requires a local TCP port, which may be blocked when MIX_ENV=test is set. I wonder if I can run mix test withMIX_SYNC=0. It might help to search for environment variable names in the Mix source to clarify.
• Ran elixir -e ‘IO.puts(:code.lib_dir(:mix))’└ /Users/john/.asdf/installs/elixir/1.19.4-otp-28/bin/../lib/mix
• Explored└ Search Mix.Sync.PubSub|sync.pubsub|MIX_SYNC in mixRead pubsub.ex
• I’m thinking that PubSub might only kick off if “mix sync” is enabled. I wonder if this feature is limited to a test environment? It feels like it could be a specific setup detail. So, to clarify everything, I should take a look at theMix.PubSub module. This will help me confirm how it works and whether any particular conditions need to be met for it to activate. Let’s dive into that!
• Explored└ Read pubsub.ex
• I’m trying to understand why we didn’t see an error in the development environment. It seems that Mix.PubSub might not start there, possibly because it’s only initiated when Mix.env() == :test for supporting Mix.Sync across tests.Interestingly, mix help worked fine in the dev environment, which makes me think PubSub didn’t start. It could be that deps.loadpaths only activates Mix.PubSub in the test environment. I’ll check Mix.Tasks.Deps.Loadpaths to figure thisout.
• Explored└ Read deps.loadpaths.ex, subscriber.ex
• I’m wondering why socket operations succeed in the dev environment but fail in the test environment. It seems like the build paths differ, but they shouldn’t affect permissions. I’m considering that maybe they use different :gen_tcp.listenoptions in dev. However, the mix help command works in dev but fails with MIX_ENV=test. This suggests that the permission issue might relate to the environment variable MIX_ENV, possibly restricted by sandbox settings that deny networkaccess when set to test.
Investigating the permission error
I’m thinking that it seems unlikely, but maybe the harness could restrict network commands based on specific patterns. However, I realize it’s more likely related to OS-level issues. The MIX_ENV=test mix help command uses the MIX_ENV=testvariable, affecting Elixir’s Mix.env and compile path, but this shouldn’t influence TCP connections. I wonder if the permission error, :eperm, could arise from trying to bind to a privileged port by mistake, but Mix uses port 0, whichshould avoid that issue.
Examining sandbox restrictions
I’m considering whether the sandbox imposes network restrictions, allowing loopback binding for certain ports only. It seems like the development environment might be treated differently, but the options specify the same IP. I’mquestioning if the environment variable MIX_ENV affects the binding permissions — maybe it alters how the build path is perceived, though that shouldn’t matter for socket binding.
To investigate, I think it’s worth running a simple Elixir script to listen on a socket with MIX_ENV set and unset, checking for any errors. This should clarify whether the OS imposes restrictions.
Testing socket permissions
I’ll run elixir -e to test using Erlang’s :gen_tcp.listen, which bypasses Mix. If that command succeeds, it indicates that the OS allows socket creation. If it works, I’ll have to dig deeper into why the Mix commands are failing, as theyshouldn’t be restricted if this command runs smoothly. I’m curious about the underlying differences between the two environments, and I want to clarify whether the issue lies with Mix itself.
• Ran elixir -e ‘IO.inspect(:gen_tcp.listen(0, \[:binary, ip: {127,0,0,1}, packet: :raw, nodelay: true, backlog: 128, active: false\]))’└ {:error, :eperm}
• In this thought, I’m considering if mix run scripts/perf/explain_foo.exs is a fresh process. I’m questioning whether the command executed using exec_command might influence that. It looks like exec_command runs a single command andreturns output, so each call is separate. I’m trying to figure out if the environment is clean or if the Mix.PubSub could be still running. It’s complex, but I’m working through it!
Investigating Mix.PubSub behavior
I’m diving into how Mix.PubSub operates within the Erlang VM while running mix run scripts/perf/explain_foo.exs. When that command finishes, the VM stops, and so does PubSub, unless a background VM was initiated, which it wasn’t. Thisraises questions about how mix run successfully calls deps.loadpaths, which needs PubSub. I wonder if the command defaults to dev environment instead of the expected test. Yet, when I explicitly ran it in the test environment, itsucceeded. I’m puzzled by the differences between running scripts and eval.
Exploring command behavior in Mix
I’m pondering why some commands succeed while others fail due to starting the PubSub subscriber. Our Elixir test shows that :gen_tcp.listen returns :eperm, which suggests a failure for any mix command that starts PubSub. Yet, commands likemix help and mix run script succeeded, possibly indicating they didn’t activate the PubSub. Maybe those commands bypassed the deps.loadpaths, perhaps because dependencies were already cached or Mix was invoked with --no-deps-check. Theumbrella structure could also contribute here. It’s quite a tangled web!
Analyzing mix run behavior
I want to figure out what happens when I execute mix run scripts/perf/explain_foo.exs. It starts by calling ensure_all_started(:foo_app), which means the project needs to compile and load first. Could I have run this as part of amix run alias in mix.exs? The default task appears to be “mix run,” probably because they set default_task: “run”. To clarify, I think I should attempt MIX_ENV=test mix deps.loadpaths --no-listeners --no-deps-check to see if it fails dueto the PubSub start.
Searching for Mix.PubSub options
I’m considering if setting an environment variable like MIX_REPLICA=1 might help, but that doesn’t seem to work. Since I can’t open TCP sockets, I realize I need to disable Mix’s PubSub feature entirely to allow mix tasks to run smoothly.I wonder if there’s an environment variable to disable either Mix.Sync.PubSub or Mix.PubSub. Alternatively, could I patch my project to prevent starting PubSub? I’m also thinking about setting configurations like MIX_EXS for listeners, butI’ll search for mix_pubsub or MIX_PUBSUB in the source instead.
• Explored└ Search MIX_PUBSUB|mix_pubsub in mixSearch Mix.Sync|sync. in mix
• I’m trying to figure out how to disable PubSub. I’m thinking there might be an environment variable like MIX_NO_PUBSUB, but I didn’t find it. Perhaps there’s a command line option --no-pubsub, but it doesn’t seem to exist. Theenvironment’s limitation with TCP sockets is causing issues with Mix’s pubsub. We’ve run some mix tasks that didn’t initiate pubsub, which is interesting. I wonder if the dev environment has a different compilation path. Running tests istricky without tasks starting pubsub, but maybe I can run ExUnit directly? However, tests generally need Mix for environment and configuration.
Considering Mix compile issues
I’m wondering if mix compile might work if it doesn’t start pubsub. I think running it in the test environment could fail due to pubsub, but maybe the dev environment would be better? However, tests typically require the test environmentconfiguration. This is getting tricky! It seems like the error might come from sandbox restrictions on TCP sockets. I wondered about options like using Unix domain sockets or setting MIX_SYNC=true, but neither seems to pan out. Ultimately,it seems any Mix task that starts pubsub is going to fail here. But how did mix run scripts/perf/explain_foo.exs actually succeed? It must not have initiated a pubsub subscriber.
Exploring mix run behavior
I’m checking how mix run starts a subscriber and calls subscribe, which would usually lead to a failure with :gen_tcp.listen. But surprisingly, it didn’t fail, indicating our assumption about mix run scripts/perf/explain_foo.exstriggering deps.loadpaths might be incorrect. Perhaps since it’s an umbrella with pre-compiled dependencies, mix run acts like an “embedded” task that skips loading paths? But that contradicts the usual behavior. I think mix tasksgenerally run loadpaths, but maybe mix run does it differently with specified script paths. I’ll test this by running MIX_ENV=test mix compile to see if it fails.
• Ran cd /Users/john/Developer/Demo/demo_server && MIX_ENV=test mix compile└ \*\* (RuntimeError) failed to start Mix.PubSub, reason: {{:shutdown, {:failed_to_start_child, Mix.PubSub.Subscriber, {%Mix.Error{message: “failed to open a TCP socket in Mix.Sync.PubSub.subscribe/1, reason: :eperm”, mix: 1}, \[{Mix, :raise,2, \[file: \~c"lib/mix.ex", line: 647\]}, {Mix.PubSub.Subscriber, :init, 1, \[file: \~c"lib/mix/pubsub/subscriber.ex", line: 24\]}, {:gen_server, :init_it, 2, \[file: \~c"gen_server.erl", line: 2276\]}, {:gen_server, :init_it, 6, \[file:… +8 lines(mix 1.19.4) lib/mix/task.ex:499: anonymous fn/3 in Mix.Task.run_task/5(mix 1.19.4) lib/mix/cli.ex:129: Mix.CLI.run_task/2
• The compilation fails, but the script runs successfully. That suggests the script executed without starting the PubSub. I think it might be the way I ran the script. Even though it succeeded directly, I’m wondering if it executed a cachedversion instead of compiling. The output indicates “Wrote EXPLAIN outputs,” but I didn’t see any compilation logs or errors. I’m curious if mix run bypasses project loading and dependencies. It seems that could be a factor too!
Evaluating Mix Environment Execution
I want to confirm that running MIX_ENV=test mix run -e ‘IO.inspect(Mix.Project.get())’ might fail because of PubSub. However, the script can still execute without loading the project, which could prevent dependency compilation. Since thescript starts with Application.ensure_all_started(:foo_app), it may still run if the code is available. I wonder if running mix run in the umbrella root loads code paths. In a new VM, the compiled code might not be available, just thestandard library. So it seems like it must load from the code path!
Analyzing Mix Run Behavior
It seems that mix run likely loaded the project apps and dependencies, which typically requires loading paths. However, I’m curious if it uses --no-mix-exs, but that doesn’t seem right. I think inspecting the mix run task implementationmight help. Running MIX_ENV=test mix run --verbose could provide insights, but since compilation fails, I’m unsure. Maybe mix run avoids starting Mix.PubSub if there’s a \_build/test directory. If Mix.Tasks.Deps.Loadpaths.run isn’t called,that might explain why it didn’t fail!
Examining Environment Variables and Paths
I’m wondering if there’s a shell alias for mix that sets MIX_ENV=dev, but that doesn’t seem to be the case. When I ran MIX_ENV=test mix run scripts/perf/explain_foo.exs, it succeeded quickly, which makes me think it might not havecompiled but used existing artifacts from \_build/dev. Since the dev environment doesn’t trigger PubSub issues, I’m questioning if the build path is still \_build/dev for some reason. Maybe MIX_BUILD_PATH is affecting it, allowing for anoverride to /tmp/… if set?
Checking Build Path Environment Variable
I’m considering that in earlier prefix rules, they might have set MIX_BUILD_PATH=/tmp/collabdock-tech-5027/\_build for some tests. But that was probably for a previous run. It’s possible this environment has MIX_BUILD_PATH set in the shellprofile to a path with precompiled artifacts. So, I think the next step is to check the current value of the MIX_BUILD_PATH environment variable by running echo $MIX_BUILD_PATH. That could clarify things!
• Ran echo ${MIX_BUILD_PATH-}└
• I’m wondering if the repository might have a build_path configured within mix.exs. That seems like a possibility worth exploring. So, I’ll check the root mix.exs file to see if there’s indeed any configuration related to build_path. It’simportant to get this right, so my next step is to delve into that file and verify the settings. Let’s see what we can find!
• Explored└ Read mix.exs
• I’m trying to figure out if there might be any compiled artifacts checked into the repo, though usually that’s not the case. I wonder if there could be something like apps/foo_app/ebin in the source? I think it’s a good idea to checkthat directory with the command ls apps/foo_app/ebin. That might clarify whether those files exist or not!
• Explored└ List foo_app
• I’m trying to understand how tasks in Mix work. It seems that running mix loadpaths calls Mix.Tasks.Deps.Loadpaths, but it’s unclear if mix run scripts/perf/explain_foo.exs uses caching and skips deps.loadpaths. Yet, it seems to workeven when mix compile fails. I’m considering running with --no-start to check. Additionally, it seems that running a script path might not be handled the same way as using the elixir command directly.
Analyzing Script Execution in Mix
It seems like running a script may not load or compile the project directly; it simply runs the script file. The script calls Application.ensure_all_started(:foo_app), which could fail if the app isn’t loaded. Still, mix run generallyloads and compiles the project by default. I wonder if running mix run scripts/perf/explain_foo.exs invokes the “run” task but somehow defaults to a dev environment. Interestingly, this command succeeded despite previous compilationfailures, indicating that deps.loadpaths didn’t start the pubsub subscriber in this case.
Exploring Mix Environment Behavior
I’m considering why running the script with MIX_ENV=test seemed to bypass the pubsub subscriber. The script starts with a check for the environment using Mix.env(), and since it didn’t raise an error, it confirms it’s running in the testenvironment. I’m thinking it might be that when using mix run, it runs with flags like --no-compile or --no-deps-check implicitly. This could explain why it doesn’t trigger the deps.loadpaths step, as it’s potentially using alreadycompiled code from previous runs.
Examining Mix Run Dependencies
I’m pondering how mix run uses mix app.config, which should invoke compile tasks and deps.loadpaths. I’m thinking about running MIX_ENV=test mix run --no-compile scripts/perf/explain_foo.exs to see if it succeeds by avoiding thecompilation and thereby sidestepping pubsub. However, it seems that deps.loadpaths might still start pubsub before the compilation happens. Maybe the start of the pubsub subscriber only triggers when tasks require dependencies, but thescript does use dependencies like Ecto, so they must be included in the execution path somehow.
Investigating Dependency Loading
I’m thinking about how dependencies might be loaded—maybe through system applications—but that doesn’t seem right here. It’s odd that the script runs successfully despite socket errors, as it suggests that Mix.PubSub didn’t subscribe. Iwonder if Mix.PubSub.start was ever called, since Mix.Tasks.Deps.Loadpaths should definitely invoke it. However, if the script doesn’t run deps.loadpaths, perhaps it’s because our project is the umbrella root with no specific dependencies.I should check if mix loadpaths invokes deps.loadpaths.
• Explored└ Read loadpaths.ex
• I’m exploring the installation of ‘phoenix’ as an archive. Historically, it uses mix tasks within dependencies, and to generate a new project, I would install the ‘phx_new’ archive. But I wonder if they also have ‘Phoenix’ installed as anarchive. Similarly, Ecto tasks might come from an Ecto archive, but there’s also the “ecto_sql” application for tasks. I’m thinking that perhaps ‘mix help’ includes tasks from the umbrella root, since mix loads apps in ‘apps/’. It seemslike it might include child app compile paths automatically too.
Analyzing mix tasks and dependencies
I’m considering how the task list includes tasks from dependencies of child apps that are compiled and path-accessible in the development environment. Maybe ‘mix help’ uses load paths with --no-deps-check, but I’m not sure. It seems ‘mixhelp’ could succeed in a dev environment even if ‘:gen_tcp.listen’ fails. If ‘Mix.PubSub.start’ wasn’t executed, that could explain why, as it might not call load paths or start up properly, even if it listed tasks from the archives likeEcto or Phoenix.
Exploring mix task execution
I’m thinking about how tasks like ‘mix ecto.migrate’ might come from the ‘ecto_sql’ archive, but I’m not really sure. Our project tasks requiring compilation failed due to ‘Mix.PubSub’ not opening sockets. Yet, we successfully ran ‘mix runscripts/perf/explain_foo.exs’ without starting pubsub. Maybe this happened because we executed it in a way that skipped Mix’s dependency loading, possibly using a precompiled build. However, it seems that ‘mix run’ succeeded, implyingthat pubsub didn’t fail, or maybe it only fails when building from scratch.
Examining network restrictions in Elixir
I’m wondering if our Elixir test ‘:gen_tcp.listen’ fails with ‘:eperm’ because network access is restricted in the sandbox. However, it’s possible that certain commands could open sockets with escalated permissions. By default, commandsrun within the sandbox, so maybe our previous successful ‘mix run scripts/perf/explain_foo.exs’ ran outside of it due to an approved prefix rule. The developer message indicates that network access is restricted, but perhaps commandscan access the network in escalated mode. Still, we haven’t used ‘require_escalated’ with our commands yet.
Investigating sandbox restrictions and network access
I’m puzzling over why ‘:gen_tcp.listen’ fails due to network socket restrictions in a sandboxed environment. If I run a command with sandbox_permissions: require_escalated, could it allow opening sockets? Our earlier successful mix runscripts/perf/explain_foo.exs might have bypassed this restriction because it matched an approved prefix, enabling socket access. However, it didn’t require sockets. Since our ‘mix test’ command likely runs in the sandbox, it couldexplain the failure, though I wonder if it should have matched the approved prefixes. It’s quite complicated!
Exploring mix test execution and environment settings
I’m trying to understand why our mix test command fails. It looks like setting MIX_ENV=test causes the first token to change, which doesn’t match the prefix rule expecting mix as the first token. If our command had started with mix, itmight have run outside the sandbox. However, mix help succeeded, possibly due to matching an approved prefix that allows socket access. I think we need to test running mix test without the environment assignment to see if it works withouttriggering restrictions.
Testing mix test execution
I just remembered that running mix test automatically sets the environment to :test, creating the \_build/test directory. This implies we could run our earlier mix test command without explicitly setting MIX_ENV. If we have an approvedprefix rule for \[“mix”,“test”\], it might mean it runs outside the sandbox. To see what happens, I’ll run mix test apps/foo_app/test without the environment assignment, even though it might still fail due to pubsub socket restrictions.Let’s give it a shot!
• Ran cd /Users/john/Developer/Demo/demo_server && mix test apps/foo_app/test└ ==> foo_appRunning ExUnit with seed: 901435, max_cases: 16… +2 linesFinished in 4.2 seconds (4.2s async, 0.00s sync)183 tests, 0 failures
• I’m excited that mix test apps/foo_app/test succeeded without needing to set the MIX_ENV! It’s interesting because mix test seems to use the test environment, but there’s a question about socket usage. If it did try to open a TCPsocket, it should have failed, but since it succeeded, maybe Mix.PubSub wasn’t started or it was executed outside the sandbox. This could be due to approved prefix rules allowing TCP socket use. There are definitely intriguingpossibilities here!
Finalizing test execution
It seems plausible that running mix test without an environment assignment allows Mix.Sync.PubSub to open a socket successfully. The earlier command using MIX_ENV=test didn’t match the prefix rule and failed because it was executed insidethe sandbox. But now that I know I can run the tests without that assignment, I feel great about completing step 6 (running tests). I’ll mark this plan accordingly — all set!
