Error handler with context

[frenzzy]

The router no longer mutate errors to avoid issues with non-extensible objects.
If your code relies on error.context or error.code you still can access the same variables using errorHandler option:

errorHandler(error, context) {
  const code = error.status || 500
  console.log(error, context, code)
}

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)

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.

Closes #152
Closes #154
Closes #156

[codecov-io]

Codecov Report

Merging #158 into master will not change coverage.
The diff coverage is 100%.

@@          Coverage Diff          @@
##           master   #158   +/-   ##
=====================================
  Coverage     100%   100%           
=====================================
  Files           4      4           
  Lines         147    144    -3     
  Branches       44     42    -2     
=====================================
- Hits          147    144    -3

Impacted Files	Coverage Δ
src/UniversalRouter.js	100% <100%> (ø)	⬆️

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[gpoitch]

Checking the message string feels dirty. How about a 3rd arg for the code?

[frenzzy]

I think it is better to use a special route with (.*) path for not found errors. This example just shows how easy to reach a backward compatibility. Maybe need to mention it, what do you think?

[gpoitch]

Agree on the special route and would put that in the docs. I wouldn't encourage the string check and explicitly mention it's for backwards compat.