(Will remove)

Actually displaying null...

I don't see null when I run this locally. Are you ensuring the cached tool snapshot is up to date? See https://github.com/flutter/flutter/wiki/The-flutter-tool#making-changes-to-the-flutter-tool for more context.

will check that.

Currently i run my unit test with this command :

$>  dart bin/flutter_tools.dart test test/commands.shard/hermetic/clean_test.dart

will check that.

Currently i run my unit test with this command :

$>  dart bin/flutter_tools.dart test test/commands.shard/hermetic/clean_test.dart

Well if it's showing null in unit tests, that's different :) That means your test is set up wrong.

will check that.
Currently i run my unit test with this command :

$>  dart bin/flutter_tools.dart test test/commands.shard/hermetic/clean_test.dart

Well if it's showing null in unit tests, that's different :) That means your test is set up wrong.

Need help on that, didn't know what is wrong inside the test... Just trying to use my flag inside test...

I pushed a new version with a working test. Maybe not the best test ever, do not hesitate to tell me what changes need I do.

Exceptions here were hidden. If xcode didn't find scheme or throw something it's important to abort no ? I've edited that.

@christopherfujino Do you have any opinions on this? In particular, is it appropriate to throw a ToolExit in the case of input error (i.e. no scheme given)?

@christopherfujino Do you have any opinions on this? In particular, is it appropriate to throw a ToolExit in the case of input error (i.e. no scheme given)?

I'm not sure I understand the question. Are you asking if we should printError and exit 0 when the user provides a non-existent scheme? If so, then I think tool exiting is the right course of action (ToolExit generally means that we cannot continue because of some invalid state, usually based on user inputs).

If I'm misunderstanding the question, please clarify.

Three new ToolExit throws are added here:

https://github.com/flutter/flutter/blob/8c7682a933a9fb856631706da2e9e1fb49bf1d18/packages/flutter_tools/lib/src/commands/clean.dart#L91-L96

and

https://github.com/flutter/flutter/blob/8c7682a933a9fb856631706da2e9e1fb49bf1d18/packages/flutter_tools/lib/src/commands/clean.dart#L103-L105

(side note: the first two shown in the first code snippet will get caught by the catch in the second code snippet, in which case a different ToolExit is thrown)

However, in other cases throughout the tool, debug.printError is used without throwing a ToolExit. Example:

Going back to the three newly added ToolExit throws, is it appropriate to throw here instead of just printing an error message? Asked more specifically:

1. Is it appropriate to throw if a user provides an invalid Xcode scheme name (or doesn't provide one at all despite using --scheme), or should we print an error message and continue with cleaning?
2. Is it appropriate to throw if something goes wrong with cleaning a workspace, or should we print an error message and continue with cleaning?

Three new ToolExit throws are added here:

https://github.com/flutter/flutter/blob/8c7682a933a9fb856631706da2e9e1fb49bf1d18/packages/flutter_tools/lib/src/commands/clean.dart#L91-L96

and

https://github.com/flutter/flutter/blob/8c7682a933a9fb856631706da2e9e1fb49bf1d18/packages/flutter_tools/lib/src/commands/clean.dart#L103-L105

(side note: the first two shown in the first code snippet will get caught by the catch in the second code snippet, in which case a different ToolExit is thrown)

However, in other cases throughout the tool, debug.printError is used without throwing a ToolExit. Example:

flutter/packages/flutter_tools/lib/src/commands/clean.dart

Lines 101 to 104 in 378387b

	} on FileSystemException catch (err) {
	globals.printError('Cannot clean ${file.path}.\n$err');
	return;
	}

Going back to the three newly added ToolExit throws, is it appropriate to throw here instead of just printing an error message? Asked more specifically:

1. Is it appropriate to throw if a user provides an invalid Xcode scheme name (or doesn't provide one at all despite using --scheme), or should we print an error message and continue with cleaning?

This to me seems like a clear user error, and thus should be a tool exit.

2. Is it appropriate to throw if something goes wrong with cleaning a workspace, or should we print an error message and continue with cleaning?

It makes sense to me printError and continue cleaning, but I don't have a strong opinion either way.