Cast className using toString

[porsager]

Description

When mithril normalizes classNames it now ensures toString is called before concatenating strings. This ensures mithril works like the browser does when setting dom.className =. The browser always calls toString for either dom.classList.add() or dom.className =

Motivation and Context

This makes mithril behave more like the dom, and allows bss (and maybe others) to support casting to a className using a period when doing

m('div' + b('background blue')) => m('div.bssClass')

and not adding a period when doing

m('div', { class: b('background blue') }) => m('div', { class: 'bssClass' })

flems with fixed mithril

flems without fix

How Has This Been Tested?

Added a test to check if toString is called when using className attr.

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)
• Documentation 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.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.
• I have updated docs/change-log.md

[dead-claudia]

LGTM

[dead-claudia]

This reads more like a bug than anything (hence the quick merge). @porsager If you wouldn't mind, would you like to ensure the rest of the renderer prefers toString over valueOf for coercing to strings?

[porsager]

Sure thing, I'll try to go through it Monday 😉

[porsager]

Ok, just went through it, and I don't think there are other places where it matters.

There is some "" + value usage, but that's dom.value, so I don't think that should change..

[dead-claudia]

Okay, thanks!