Make loader aware of "internal" partials

[andreyvolokitin]

When partial is failing to be resolved there is an error thrown here, which interferes with the use of inline partials and failover content of partial blocks (#106, #135 ). Currently, handlebars-loader considers any partial names as external partials. But some partials with names not necessarily should be external (i.e. inline partials), or it may be acceptable to not have a resolved partial by this name if it is a partial block (which always has failover content).

I used AST Visitor to save names of any partial blocks and inline decorators in the current template. In case of resolve error, I check if the name of a partial from failed request is the one of those saved names and if that is the case I proceed with return partialCallback(); so that Handlebars can do all remaining work. In other case I pass error along as usual

[coveralls]

Coverage decreased (-3.4%) to 83.534% when pulling 35580ca on andreyvolokitin:internal-partials-resolving into 67657e2 on pcardune:master.

[coveralls]

Coverage decreased (-3.4%) to 83.534% when pulling d742f53 on andreyvolokitin:internal-partials-resolving into 67657e2 on pcardune:master.

[pcardune]

Thanks for the pull request! Do you think you can add some unit tests for this fix?

[andreyvolokitin]

I am actually not familiar with unit testing and testing in general. I read wiki on it a bit but still has no clue what to test and how... The only new "thing" is InternalBlocksVisitor, which is just an extension of Handlebars Visitor with minor and trivial changes

[andreyvolokitin]

I will try it though

[coveralls]

Coverage increased (+2.2%) to 89.157% when pulling f984f28 on andreyvolokitin:internal-partials-resolving into 67657e2 on pcardune:master.

[andreyvolokitin]

Are my tests ok?

[pcardune]

Looks good! Thank you. I'll publish a new release in the next few days.

[aparshin]

@andreyvolokitin thank you for this PR!
@pcardune when are you going to publish new version?