fix(condition): handling of missing source and/or target keys

[jtan-brex]

Description

Adds additional handling of missing source and/or target keys in condition package number equal to and string equal to.

Motivation and Context

Fix for issue:Condition Package Zero Value Matches Can Be Inaccurate #263.

Current behaviour of condition package does not contain source key or target key's object path existence check. This caused unexpected behaviour:

• When only src key is present but the path doesn't exist, condition package inaccurately matches on zero value and empty string.

• When both source key and target key are present but both paths do not exist, the number equal to and string equal to return true.

This adds checks thus

• when source key or target key is present in condition package number equal to and string equal to, but either of path does not exist in the object, then condition equal to check return false.

How Has This Been Tested?

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.

[jshlbrd]

Any tests that return false should be labeled as "fail" ("pass" is for tests that return true).

[jtan-brex]

gotcha, thanks for pointing that out! fixed test cases to reflect expected 'fail' outcomes.

[jshlbrd]

There will need to be more work on this prior to the next major update. I think we can do this in more places, but not everywhere without introducing a breaking change.