Don't stop scan on invalid inline property annotation

[jrfnl]

Description

Recreation of upstream PR squizlabs/PHP_CodeSniffer#3916:

Follow up on squizlabs/PHP_CodeSniffer#3629, which was merged for PHPCS 3.8.0.

PR squizlabs/PHP_CodeSniffer#3629 added logic to throw a "Ruleset invalid. Property "$propertyName" does not exist on sniff ..." error.

This error is intended for the command-line when reading the phpcs.xml.dist ruleset file.

However, this error could also be encountered if an inline // phpcs:set ... annotation would try to set a non-existent property.

While the use of // phpcs:set is typically reserved for sniff test case files, there is nothing stopping end-users from using the annotation.

The net-effect would be:

• The Ruleset::setSniffProperty() throws a RuntimeException.
• This exception is then passed to File::addMessage() where it is not thrown as the line on which the error is being thrown is an annotation line.
• The scan of the file stops dead in its tracks as a RuntimeException was encountered.
• The end-user doesn't know the file does not finish scanning as no Internal error is shown for the file.

To me, this is counter-intuitive and counter-productive as it may give people a false sense of security (CI is green, while in reality files are not being scanned).

To fix this, I propose the following:

• Collect all // phpcs:set related inline annotations encountered while scanning.
• Do not stop the file scan for these errors.
• Add a warning with information about the incorrect annotations on line 1 once the file has finished scanning.

Includes a test via the Generic.PHP.BacktickOperator sniff.

Suggested changelog entry

I'd suggest updating the existing changelog entry for the change from PR squizlabs/PHP_CodeSniffer#3629 and adding:

    -- Invalid sniff properties set for sniffs via inline annotations will result in an informative `Internal.PropertyDoesNotExist` errror on line 1, but will not halt the execution of PHPCS

Types of changes

• Bug fix (non-breaking change which fixes an issue)