google/process.dart

Process

Moved

The source for the platform package has moved to the flutter/packages repository.

---

A generic process invocation abstraction for Dart.

Like dart:io, package:process supplies a rich, Dart-idiomatic API for spawning OS processes.

Unlike dart:io, package:process:

• Can be used to implement custom process invocation backends.
• Comes with a record-replay implementation out-of-the-box, making it super easy to test code that spawns processes in a hermetic way.

process.dart's Issues

Please publish a new version, which is compatible with Dart SDK ^2.1.0

The next flutter/engine -> flutter/flutter roll will receive a new 2.1.0-dev Dart SDK, which requires us to upgrade all 3rd party packages. Most of them have already newer versions published which are compatible with Dart 2, but the latest commits to this package:process repository haven't been published yet.

@tvolkert @goderbauer Would you mind publishing a new version? (This is blocking flutter/flutter#20427)

Where is the record-replay functionality

The readme talks about

Comes with a record-replay implementation out-of-the-box, making it super easy to test code that spawns processes in a hermetic way.

but I couldn't find any info about it except that it was removed.

See also:

• #47

[Bug] Can't run system commands in Windows.

I'm wondering If run designed to run executable?

example:

// Not working
processManager.run(['tasklist | findstr svchost.exe'], runInShell: true);
// error: '\"tasklist | findstr svchost.exe\"' is not recognized as an internal or external command,
// Neither(note)
processManager.run(['', 'tasklist | findstr svchost.exe'], runInShell: true);

So there is no possible to use these kind of commands, only for pure Process.

// Working
Process.run('tasklist | findstr svchost.exe', [], runInShell: true);
// Not working (note)
Process.run('', ['tasklist | findstr svchost.exe'], runInShell: true); 

Note: After viewing source code, I want to bypass this change, but It's not possible, Process.run with empty executable will give a double quote with empty space, see below:

'" "tasklist' is not recognized as an internal or external command,

The code affect this issue for Sanitizes the executable path on Windows.

  if (executable.contains(' ') && !executable.contains('"')) {
    // Use quoted strings to indicate where the file name ends and the arguments begin;
    // otherwise, the file name is ambiguous.
    return '"$executable"';
  }

ProcessManager.run* should throw ProcessException if executable not found

As of #3, it throws ArgumentError instead.

/cc @goderbauer

Upgrade from comment-based generics syntax

The comment-based generics syntax will be removed from the Dart SDK tools (like DDC, analyzer) "soon." dart-lang/sdk#28796

Such syntax (like in _areListsEqual) needs to be updated, and the minimum Dart SDK in pubspec.yaml needs to be bumped to 1.21, when the real, non-comment-based syntax was introduced.

Consider transparently replacing `/` with `\` on Windows in executable path

See flutter/flutter#13978 (comment).

That way it wouldn't matter if you accidentally pass a Linux-like executable path with \ as path separator on a Windows system. It would just work.

Not sure what the implications of this are. Is there ever a reason why you want to keep a \ in an executable path on Windows?

Fix "unverified published" on pub.dev

This package should be in the google.dev publisher, but instead it's shown as belonging to an "unverified publisher".

ProcessManager.start's first argument should be List<String> not List<dynamic>

I'm implementing ProcessManager.start and I don't understand what type I could receive in the first argument's list other than String, nor what to do with any other types.

ProcessManager.run should check if the executable is an absolute path and not do its attempts to lookup the path etc. if it is

For example, processManager.run(<String>['/path/to/a/binary', 'arg1', 'arg2']); is going through this code path: https://github.com/google/process.dart/blob/master/lib/src/interface/local_process_manager.dart#L122 when I don't use runInShell.

I don't want to use runInShell though, I want it to just run the command to a process I have the abspath for.

Encoding parameters should be nullable

In the dart:io versions of the Process.run and runSync methods, the stderrEncoding and stdoutEncoding parameters are nullable. This library should be updated to match.

Due to backward compatibility constraints, this has to be done in two phases:

1. Make the parameters nullable, but with a covariant keyword. This can be done in a patch release.
2. Once all dependents are migrated, remove the covariant. This requires a major release.

When fs.currentDirectory throws, skip cwd relative search

In getExecutablePath, fs.currentDirectory is queried, but it can throw FileSystemException if e.g. getcwd() fails with EACCES, which can happen if the current process doesn't have read/list permissions from / up to the cwd.

Instead of propagating the exception, getExecutablePath should catch it, and just skip the cwd relative search.

flutter/flutter#57166

Feature request: Process.reSync(PID)

It can be good to have a way to re-sync a process, like for example:
Process.reSync(PID) and this will return a Process object.

Please add a tag to match the released version in Pub.dev

The published version can currently not be traced to a source code version.

Dart 2 runtime failures in tests

Running tests in Dart 2 mode, see the following failure

00:02 +0 -2: RecordingProcessManager run [E]
type 'List' is not a subtype of type 'List' where
List is from dart:core
List is from dart:core
String is from dart:core

package:process/src/record_replay/common.dart 15:6 sanitize
package:process/src/record_replay/recording_process_manager.dart 147:37 RecordingProcessManager.run
===== asynchronous gap ===========================
dart:async _Completer.completeError
package:process/src/record_replay/recording_process_manager.dart RecordingProcessManager.run
===== asynchronous gap ===========================
dart:async _asyncThenWrapperHelper
package:process/src/record_replay/recording_process_manager.dart RecordingProcessManager.run
../../tmp/archives/third_party/dart/process/test/record_test.dart 65:25 main..
===== asynchronous gap ===========================
dart:async new Future.microtask
../../process/test/record_test.dart 63:17 main..

Child process not killed when program exit

I'm using Process in a Flutter project.
When the main application is closed, the child process started with run or either start is not terminated as well.

Does it an issue with the process itself?

 # pstree show process as child of fluter executable
❯ pstree -p 57234                 
-+= 00001 root /sbin/launchd
 \-+= 26078 pierozi /Applications/IntelliJ IDEA CE.app/Contents/MacOS/idea
   \-+- 56973 pierozi bash /Users/pierozi/Public/flutter/bin/flutter --no-color run --machine --track-widget-creat
     \-+- 56988 pierozi /Users/pierozi/Public/flutter/bin/cache/dart-sdk/bin/dart --packages=/Users/pierozi/Public
       \-+- 57228 pierozi /Users/pierozi/Project/github/plab/PeerVault-Client/build/macos/Build/Products/Debug/Peer
         \--- 57234 pierozi sleep 3600

# After flutter closed
❯ pstree -p 57234                       
-+= 00001 root /sbin/launchd
 \--- 57234 pierozi sleep 3600

ProcessManager.run signature is inconsistent with LocalProcessManager.run

ProcessManager has:

  Future<ProcessResult> run(
    List<dynamic> command, {
    String workingDirectory,
    Map<String, String> environment,
    bool includeParentEnvironment = true,
    bool runInShell = false,
    Encoding stdoutEncoding = systemEncoding,
    Encoding stderrEncoding = systemEncoding,
  });

LocalProcessManager has:

  @override
  Future<ProcessResult> run(
    covariant List<Object> command, {
    String? workingDirectory,
    Map<String, String>? environment,
    bool includeParentEnvironment = true,
    bool runInShell = false,
    Encoding stdoutEncoding = systemEncoding,
    Encoding stderrEncoding = systemEncoding,
  }) {

Is the difference in nullability for the workingDirectory and environment arguments intended? While legal, it's confusing, and I don't see any advantage to requiring non-null arguments in the base class.

Same for ProcessManager.start and LocalProcessManager.start.

Give `LocalProcessManager` a `const` constructor...

... so it can be used as a default parameter.

getExecutablePath should only return executables

Right now, if I have the directory /tmp/bin in my PATH before /usr/bin, and it has a text file (mod 644, i.e. executable bit NOT set) in it called patch, then if I attempt to run 'patch' using Process.run or Process.start, then it will fail, because even though an executable patch exists in the PATH at /usr/bin/patch, it finds the one in /tmp/bin/patch instead and tries to execute it. It will succeed just fine if runInShell is set, since the shell skips non-executables.

getExecutablePath should, at least on Unix-like systems, only return files that have their executable bit set.

Pubspec doesn't declare Dart 2.0 SDK support

The published version of process doesn't support Dart 2:
https://pub.dartlang.org/packages/process#-analysis-tab-

However, looks like the pubspec in this repo does, so do we need to republish?

Also, there seems to be analysis issues: #26

Make compatible with file ^7.0.0