Improvements to rule expressions

[otykier]

Various improvements to existing rules:

• Use Tokenize().Any(...) instead of RegEx.IsMatch(...), when determining if a DAX expression contains certain tokens, such as specific DAX functions or the / (division) operator. Tokenization ignores whitespace/comments in the DAX expression, which improves the accuracy of the rules.
• When RegEx is used, and the RegEx pattern is constructed from one or more object names, make sure to escape the name using RegEx.Escape. Otherwise, the rule would error out when an object name contains characters that has special meaning in RegEx syntax.
• RLS-specific rules should use the "TablePermission" scope to simplify the rule expression, and to better guide the user to the object that hosts the DAX filter expression.

The Tokenize() syntax works with all current versions of Tabular Editor 2. We identified a bug in TE3 that prevented the use of Tokenize() in BPA rules, affecting versions 3.6.0 through 3.11.0, but this bug will be fixed with the release of 3.12.0, later this month.

CC @m-kovalsky

[otykier]

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[m-kovalsky]

Thanks so much Daniel! We even have best practices for the best practices :) Is the Tokenize function documented (or will it be)? Certainly makes the code much simpler. I will wait to commit these changes until you release TE 3.12.0 so folks using TE3 will not be as interrupted.

[otykier]

Is the Tokenize function documented (or will it be)? Certainly makes the code much simpler.

Yes (although it deserves its own article as you can do a lot of cool stuff once you have the list of tokens).

I will wait to commit these changes until you release TE 3.12.0 so folks using TE3 will not be as interrupted.

Awesome!