Allow withTheme to have a fallback theme when rendered outside of a ThemeProvider

Currently, when trying to test or use a component wrapped with withTheme when no ThemeProvider is found in the context, it will throw an error in componentWillMount.

[withTheme] Please use ThemeProvider to be able to use withTheme

As a result, if we want to mount a component wrapped with “withTheme” for testing - we have to wrap it manually with <ThemeProvider theme={{}}> <Component /> </ThemeProvider> to test it properly.

Was it a design decision to always require ThemeProvider to be in the tree to use withTheme? It seems odd to have such a strict requirement on this, since the styled components don’t

If not, I see two different solutions to this, either:

• Simply set the theme to be an empty object, when not found
• Allow specifying a default theme to use in the absence of a ThemeProvider when using withTheme (which could just default to an empty object, handling the previous solution by default). I’m not sure how much of a need this is

I’d be interested to hear your thoughts either way, and I’d be happy to lend a hand making any changes if you think this is something worth pursuing

[mxstbr]

I think this isn’t an issue with testing, but with inconsistency:

Was it a design decision to always require ThemeProvider to be in the tree to use withTheme? It seems odd to have such a strict requirement on this, since the styled components don’t

I agree that this is weird, and would appreciate a PR adding the behaviour from the styled components to withTheme so it’s consistent!

[brunolemos]

ThewithTheme HoC is highly attached to ThemeProvider because it doesn’t make sense to use withTheme without it.

@5id @kopax can’t you just wrap <ThemeProvider> in your tests? That’s the way you application code is, so that’s the way you should be testing it.