number filter converts null to "0"

[jbedard]

The doc says the 'number' filter:

Formats a number as text.
If the input is not a number an empty string is returned.

But passing many non-number values (null, "", " ", [], ...) return "0" because isNaN is broken.

I think the simple fix would be making the is-number check at the start of formatNumber() better, or if that is too risky of a change then the documentation should be updated. The jQuery isNumeric implementation might be best:

!isNaN( parseFloat(obj) ) && isFinite( obj )

[sidraval]

All unit tests pass after this change. It seems possible that the original behavior is intentional since JS itself treats 'null' like numeric 0.

[jbedard]

Personally I would prefer what the doc says where only numbers (possibly in a string) are formatted as numbers, and non numbers return a blank string. Even if that can't be done and null is converted to "0" I think all those other cases should return an empty string.

[sagens42]

We should use isNumber Angular function to check for a number, this is fix for this issue

angular.js/src/Angular.js

Line 457 in 686b13b

function isNumber(value){return typeof value === 'number';}

[jbedard]

I thought using isNumber would be too strict, however I see you first called parseFloat. This fixes the original issue I brought up but now number leading strings will work such as "123foobar" where parseFloat returns 123. Was that intentional?