Handle nil content value

[fractalwrench]

Goal

The notifier currently assumes that the "value" key in notable_addresses data is non-null, whereas this is not necessarily the case, which can lead to an NSInvalidArgumentException.

This change adds unit test coverage for this method, and ensures that it can handle any of the items in the dictionary being null.

Changeset

Added

Unit Tests which cover behaviour of the class.

Removed

Changed

Skip iteration if the contentValue is nil.

Review

For the submitter, initial self-review:

• Commented on code changes inline explain the reasoning behind the approach
• Reviewed the test cases added for completeness and possible points for discussion
• A changelog entry was added for the goal of this pull request
• Check the scope of the changeset - is everything in the diff required for the pull request?
• This pull request is ready for:
  • Initial review of the intended approach, not yet feature complete
  • Structural review of the classes, functions, and properties modified
  • Final review

For the pull request reviewer(s), this changeset has been reviewed for:

• Consistency across platforms for structures or concepts added or modified
• Consistency between the changeset and the goal stated above
• Internal consistency with the rest of the library - is there any overlap between existing interfaces and any which have been added?
• Usage friction - is the proposed change in usage cumbersome or complicated?
• Performance and complexity - are there any cases of unexpected O(n^3) when iterating, recursing, flat mapping, etc?
• Concurrency concerns - if components are accessed asynchronously, what issues will arise
• Thoroughness of added tests and any missing edge cases
• Idiomatic use of the language

[fractalwrench]

This change just simplifies the condition to make it more readable

[martin308]

The code change itself looks good to me.

It's not super obvious to me that there is a test case that covers the specific situation where contentValue is nil. Should there be a test where the value for the key "value" is explicitly set as nil?

[fractalwrench]

I've added both an implicit and explicit test case for where "value" can be nil. I've also added a type check as the original issue occurred if [NSNull null] was present, as this wouldn't evaluate to false but is nil.

[fractalwrench]

suppresses warnings on a redundant nsstring type check, which actually isn't redundant when contentValue is NSNull