Avoid error in type signature for Context.Isolate, NewObjectTemplate & NewFunctionTemplate

[dylanahsmith]

Fixes #108

The above issue linked to #118 (comment) where it was decided that panic may be more appropriate and idiomatic Go code in certain cases

Specifically, this makes sense when:

• there is no underlying error in the v8 API used
• any error can be equivalently checked in the caller
• the error typically represents a bug in the caller

As such, I removed error from the type signature of:

• Context.Isolate
• NewObjectTemplate
• NewFunctionTemplate

[codecov]

Codecov Report

Merging #152 (f50ba33) into master (a674d15) will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master     #152   +/-   ##
=======================================
  Coverage   96.91%   96.91%           
=======================================
  Files          12       12           
  Lines         454      454           
=======================================
  Hits          440      440           
  Misses          9        9           
  Partials        5        5           

Impacted Files	Coverage Δ
promise.go	100.00% <ø> (ø)
context.go	94.59% <100.00%> (ø)
function_template.go	100.00% <100.00%> (ø)
object_template.go	100.00% <100.00%> (ø)

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update a674d15...f50ba33. Read the comment docs.

[dylanahsmith]

An example that highlights the need for this change is that code using NewContext to create the isolate (e.g. ctx, err := v8go.NewContext()). If that succeeds, the code would be expected to close the context and dispose of the isolate to avoid a memory leak. However, the error return value prevents the isolate from being disposed of unconditionally using defer ctx.Isolate().Dispose().

[wisepythagoras]

@dylanahsmith It looks like @rogchap doesn't really care about this project anymore, so in the coming days I'll be pulling all your PRs into my forked branch to - hopefully - continue development there.

[dylanahsmith]

I talked to @rogchap on the v8go slack channel and it isn't that he doesn't care about this project, he has just been preoccupied.

For now, I would recommend continuing to contribute changes to this repo and using a fork to pull in any features blocking your work. That is the approach we are taking. In the case of this PR, it isn't a feature that is needed to unblock anything.

[wisepythagoras]

Thanks for the clarification. I didn't realize that there was a Slack channel about this. Sounds good!