{Core} Add util function highlight_command

[houk-ms]

Description

This PR adds an util function to highlight a command.

The function may be used in

• error recommendation
• az next

Testing Guide

History Notes

[Component Name 1] BREAKING CHANGE: az command a: Make some customer-facing breaking change.
[Component Name 2] az command b: Add some customer-facing feature.

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• The PR title and description has followed the guideline in Submitting Pull Requests.

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[jiasli]

Some example can be very helpful, like

azure-cli/src/azure-cli-core/azure/cli/core/util.py

Lines 1186 to 1190 in 903ecf1

	def resource_to_scopes(resource):
	"""Convert the ADAL resource ID to MSAL scopes by appending the /.default suffix and return a list.
	For example:
	'https://management.core.windows.net/' -> ['https://management.core.windows.net//.default']
	'https://managedhsm.azure.com' -> ['https://managedhsm.azure.com/.default']

[houk-ms]

Added more comments about the highlighting rules. The return type is of list of styled text, not easy to provide example.

[jiasli]

The style framework is far from perfect. I made several refinements in #16258. I suggest we put this PR on hold until #16258 is fully tested and merged.

[fengzhou-msft]

Can you add comment about the rule used?

[jiasli]

I made some comments at #16257 (comment)

The logic of = handling is for commands with positional argument. However, it works for az config set a=b, but it doesn't work for az config unset output. It is the nature of positional argument that we can NOT decide whether an arg (like output) is

• part of a command, or
• a positional argument

until semantic analysis is involved.

Let's keep it simple and treat it as part of the command by now.

[jiasli]

Another possible solution is to utilize linter_exclusions.yml which contains the full list of commands with positional arguments:

azure-cli/linter_exclusions.yml

Lines 1181 to 1185 in 2c52cbc

	config set:
	parameters:
	key_value:
	rule_exclusions:
	- no_positional_parameters

[houk-ms]

This is a good proposal, but also would make the function much more complex and harder to maintain.

I prefer we keep it simple for now, until we really need to consider the case.