"dart info" reports "No Dart processes found"

[DanTup]

Running dart info says there are no Dart processes:

danny@Dannys-MacBook-Pro sdk % ~/Dev/Dart\ SDKs/nightly/bin/dart info

If providing this information as part of reporting a bug, please review the information
below to ensure it only contains things you're comfortable posting publicly.

#### General info

- Dart 3.0.0-edge.85d1a7752eb0196ceff40f8d3a9db843db5205c2 (be) (Tue Feb 14 09:01:13 2023 +0000) on "macos_x64"
- on macos / Version 13.1 (Build 22C65)
- locale is en-GB

#### Process info

No Dart processes found.

However I have a VS Code window open that certainly has an analysis server running. If I run ps -x | grep dart I see a few:

danny@Dannys-MacBook-Pro ~ % ps -x | grep dart
10714 ??         0:05.31 /Users/danny/Dev/Google/flutter/bin/cache/artifacts/engine/darwin-x64/flutter_tester --vm-service-port=0 --start-paused --enable-checked-mode --verify-entry-points --enable-software-rendering --skia-deterministic-rendering --enable-dart-profiling --non-interactive --use-test-fonts --disable-asset-fonts --packages=/Users/danny/Dev/Google/flutter/dev/automated_tests/.dart_tool/package_config.json --flutter-assets-dir=/Users/danny/Dev/Google/flutter/dev/automated_tests/build/unit_test_assets /var/folders/b1/ftm2whhj4mb3_c4nfjhq23z00000gn/T/flutter_tools.S4PH0b/flutter_test_listener.hqexdE/listener.dart.dill
11811 ??         0:05.29 /Users/danny/Dev/Google/flutter/bin/cache/artifacts/engine/darwin-x64/flutter_tester --vm-service-port=0 --start-paused --enable-checked-mode --verify-entry-points --enable-software-rendering --skia-deterministic-rendering --enable-dart-profiling --non-interactive --use-test-fonts --disable-asset-fonts --packages=/Users/danny/Dev/Google/flutter/dev/automated_tests/.dart_tool/package_config.json --flutter-assets-dir=/Users/danny/Dev/Google/flutter/dev/automated_tests/build/unit_test_assets /var/folders/b1/ftm2whhj4mb3_c4nfjhq23z00000gn/T/flutter_tools.0LQlQj/flutter_test_listener.gwbO2M/listener.dart.dill
37260 ??         0:16.93 /Users/danny/Dev/Dart SDKs/nightly/bin/dart language-server --protocol=lsp --client-id=VS-Code --client-version=3.59.20230214 --instrumentation-log-file=/Users/danny/Dev/Dart-Code-Logs/server-project-analyzer.instrum.txt
37328 ttys008    0:00.00 grep dart

(FYI @devoncarew)

[devoncarew]

Thanks for the report! Can you run this:

ps -eo "rss,pcpu,etime,args"

and just paste in the lines for the process you think we should be reporting (dart, flutter_tester, ...). I want to verify that our parsing isn't going wrong, and / or the filtering we apply to make sure we're just reporting dart+flutter related processes.

[DanTup]

If I run that through grep dart I see this:

danny@Dannys-MacBook-Pro ~ % ps -eo "rss,pcpu,etime,args" | grep dart
111880   0.0 04:18:56 /Users/danny/Dev/Google/flutter/bin/cache/artifacts/engine/darwin-x64/flutter_tester --vm-service-port=0 --start-paused --enable-checked-mode --verify-entry-points --enable-software-rendering --skia-deterministic-rendering --enable-dart-profiling --non-interactive --use-test-fonts --disable-asset-fonts --packages=/Users/danny/Dev/Google/flutter/dev/automated_tests/.dart_tool/package_config.json --flutter-assets-dir=/Users/danny/Dev/Google/flutter/dev/automated_tests/build/unit_test_assets /var/folders/b1/ftm2whhj4mb3_c4nfjhq23z00000gn/T/flutter_tools.S4PH0b/flutter_test_listener.hqexdE/listener.dart.dill
111424   0.0 04:15:20 /Users/danny/Dev/Google/flutter/bin/cache/artifacts/engine/darwin-x64/flutter_tester --vm-service-port=0 --start-paused --enable-checked-mode --verify-entry-points --enable-software-rendering --skia-deterministic-rendering --enable-dart-profiling --non-interactive --use-test-fonts --disable-asset-fonts --packages=/Users/danny/Dev/Google/flutter/dev/automated_tests/.dart_tool/package_config.json --flutter-assets-dir=/Users/danny/Dev/Google/flutter/dev/automated_tests/build/unit_test_assets /var/folders/b1/ftm2whhj4mb3_c4nfjhq23z00000gn/T/flutter_tools.0LQlQj/flutter_test_listener.gwbO2M/listener.dart.dill
103032   0.0    17:14 /Users/danny/Dev/Google/flutter/bin/cache/dart-sdk/bin/dart --disable-dart-dev --packages=/Users/danny/Dev/Google/flutter/packages/flutter_tools/.dart_tool/package_config.json /Users/danny/Dev/Google/flutter/bin/cache/flutter_tools.snapshot daemon --show-web-server-device
 63932   0.0    17:14 /Users/danny/Dev/Google/flutter/bin/cache/dart-sdk/bin/dart devtools --machine --try-ports 10 --allow-embedding --port 9237
605388   0.0    17:14 /Users/danny/Dev/Google/flutter/bin/cache/dart-sdk/bin/dart language-server --protocol=lsp --client-id=VS-Code --client-version=3.59.20230214
   716   0.0    00:00 grep dart

However without grep, it seems like each line is truncated:

danny@Dannys-MacBook-Pro ~ % ps -eo "rss,pcpu,etime,args"            
   RSS  %CPU  ELAPSED ARGS
 27064   0.0 06:49:23 /sbin/launchd
 44628   0.0 06:49:19 /usr/libexec/logd
// SNIP
605388   0.0    17:54 /Users/danny/Dev/Google/flutter/bin/cache/dart-sdk/bin/dart lang
   648   0.0    17:31 /usr/bin/script -t 0 /dev/null xcrun xcdevice observe --both
  2104   0.0    09:31 /System/Library/PrivateFrameworks/ToneLibrary.framework/Versions
  6080   0.0    09:31 /System/Library/Frameworks/AudioToolbox.framework/XPCServices/co
 88992   0.3    01:08 /System/Applications/Utilities/Terminal.app/Contents/MacOS/Termi
158608   0.0    00:28 /Applications/Google Chrome.app/Contents/Frameworks/Google Chrom
 41528   0.0    00:27 /Applications/Google Chrome.app/Contents/Frameworks/Google Chrom
  2156   0.0    17:53 /bin/zsh -il
 34044   0.0 06:15:27 /Applications/Xcode.app/Contents/Developer/usr/bin/xcdevice obse
 34160   0.0 06:14:20 /Applications/Xcode.app/Contents/Developer/usr/bin/xcdevice obse
 33932   0.0    17:31 /Applications/Xcode.app/Contents/Developer/usr/bin/xcdevice obse
 33796   0.0 04:42:09 /Applications/Xcode.app/Contents/Developer/usr/bin/xcdevice obse
 34000   0.0 04:22:19 /Applications/Xcode.app/Contents/Developer/usr/bin/xcdevice obse
 33820   0.0    57:41 /Applications/Xcode.app/Contents/Developer/usr/bin/xcdevice obse
 33952   0.0 04:12:32 /Applications/Xcode.app/Contents/Developer/usr/bin/xcdevice obse
  4184   0.0    01:08 login -pf danny
  2584   0.0    01:08 -zsh
  1340   0.0    00:00 ps -eo rss,pcpu,etime,args
danny@Dannys-MacBook-Pro ~ % 

Not sure why it's truncated, or if that's what you're getting. I can try to debug locally if this seems odd.

[devoncarew]

Hmm, I do see the truncation - perhaps something it does for an interactive process? I don't see if when piped to a file, and don't think we see it when shelling out to that command from dart.

I'll see if I can repo the issue now w/ your output from above.

[DanTup]

Oh I see what's going on.. this only happened for some projects, and it looks like it's when my Dart SDK path has a space in it:

danny@Dannys-MacBook-Pro ~ % ps -eo "rss,pcpu,etime,args" | grep dart
484340  81.6    00:07 /Users/danny/Dev/Dart SDKs/nightly/bin/dart language-server --protocol=lsp --client-id=VS-Code --client-version=3.59.20230214 --instrumentation-log-file=/Users/danny/Dev/Dart-Code-Logs/server-project-analyzer.instrum.txt
                                           ^ space here

[devoncarew]

OK, gotcha - I think w/ that I'll be able to repro this issue.

[DanTup]

Yep, confirmed. I ran the command locally and changed this:

bool _isProcessDartRelated(ProcessInfo process) {
  return process.command.toLowerCase() == 'dart' ||

And now that one shows up (because my folder with a space happens to have "Dart" before the space). You might need to find a way to get ps to output in a way that doesn't have ambiguous spaces 🙃

[devoncarew]

Yeah, that doesn't look easy. From https://unix.stackexchange.com/questions/485999/how-can-i-parse-the-output-of-ps-to-different-fields, the parsable flags of ps aren't available on the mac (ps -o '%p,%a,%c,%y').

[DanTup]

In man ps I have:

      -c      Change the “command” column output to just contain the executable name, rather than the full command line.

If I add this, then the paths with the problematic spaces are gone:

danny@Dannys-MacBook-Pro ~ % ps -eco "rss,pcpu,etime,args" | grep dart
112044   0.0 05:04:45 listener.dart.dill
111592   0.0 05:01:09 listener.dart.dill
 63596   0.0    08:36 dart devtools --machine --try-ports 10 --allow-embedding --port 9237
608572   0.0    08:36 dart language-server --protocol=lsp --client-id=VS-Code --client-version=3.59.20230214
119120   0.0    08:11 test.dart
130892   0.0    08:02 listener.dart.dill
   520   0.0    00:00 grep dart

If you do need to get those paths back, you could always grab the PIDs from here and then re-run without the -c and look it up there?

[DanTup]

Actually, that output seems to capture the last argument for some things :/ For example those showing listener.dart.dill look like this in the full output:

112056   0.0 05:07:28 /Users/danny/Dev/Google/flutter/bin/cache/artifacts/engine/darwin-x64/flutter_tester --vm-service-port=0 --start-paused --enable-checked-mode --verify-entry-points --enable-software-rendering --skia-deterministic-rendering --enable-dart-profiling --non-interactive --use-test-fonts --disable-asset-fonts --packages=/Users/danny/Dev/Google/flutter/dev/automated_tests/.dart_tool/package_config.json --flutter-assets-dir=/Users/danny/Dev/Google/flutter/dev/automated_tests/build/unit_test_assets /var/folders/b1/ftm2whhj4mb3_c4nfjhq23z00000gn/T/flutter_tools.S4PH0b/flutter_test_listener.hqexdE/listener.dart.dill

I would say the process here should've been flutter_tester? 🤔

Edit: I thought maybe pgrep could be the answer, but I can't get it to return those flutter_tester processes no matter what pattern I provide, so I'm not convinced it's doing what I would expect 🙃