Allow console.warn and console.error

[limonte]

In order to implement vaadin/vaadin-grid#566 we need to allow console.warn. In future we will also need console.error.

console.log will still throw a linter error.

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This change is 

[Saulis]

I'm thinking if we should keep the default rules and add explicit ignores to the code using console as it should be quite rare?

Also, I wonder how this passes the linter: https://github.com/vaadin/vaadin-grid/blob/2.0-dev/vaadin-grid-dynamic-columns-behavior.html#L114

[limonte]

I'm thinking if we should keep the default rules and add explicit ignores to the code using console

there are no "default" rules, no-console is the recommended rule, allowing .warn() and .error() is documented: http://eslint.org/docs/rules/no-console#options

it should be quite rare

Actually, we should use console.warn() more often to improve the DX.

Also, I wonder how this passes the linter: https://github.com/vaadin/vaadin-grid/blob/2.0-dev/vaadin-grid-dynamic-columns-behavior.html#L114

Probably, it's because of the workaround with the window. context.

[tomivirkki]

I'm also in favor of keeping the rule since console.log is used a lot in development and while the rule is there, they don't accidentally end up in PRs.

I used window.console.warn to work around the linter and I think it's a neat way to explicitly mark console messages that are intended to be merged (explicit ignores are also ok IMO).

[limonte]

I'm also in favor of keeping the rule since console.log is used a lot in development and while the rule is there, they don't accidentally end up in PRs.

console.* including console.log will produce a linter error, exceptions are console.warn and console.error.

[tomivirkki]

console.* including console.log will produce a linter error, exceptions are console.warn and console.error.

Ah, right. Well in that case LGTM

[Saulis]

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Reviewed 1 of 1 files at r1.
Review status: all files reviewed at latest revision, all discussions resolved.

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