Relate unhandled rejections to source calls

[adamnovak]

I was getting nearly untraceable rejections handled at the top level of an application, with errors like Error: ENOENT: no such file or directory, mkdir '/public'. I eventually used node --inspect and breakOnException to trace them to fs functions being wrapped with universalify. The important information for debugging these errors is really the stack trace from the universalify wrapper's invocation, but that was not being preserved or at all attached to the error being passed to the rejection.

This makes sure to attach stack traces from the wrapper invocation and the callback invocation to the rejection errors, if they are normal Error objects that carry stack traces. This will make debugging failures in wrapped functions possible, because it will be possible to see where a failing wrapped function was invoked from.

The traces look like this:

Error: ENOENT: no such file or directory, mkdir '/public'
Error: Callback-based function called back with an error
    at /Users/anovak/workspace/amazon-genomics-cli/packages/cdk/node_modules/aws-cdk/node_modules/universalify/index.js:19:25
    at FSReqCallback.oncomplete (fs.js:179:23)
Error: Failing function was called from here
    at Object.mkdir (/Users/anovak/workspace/amazon-genomics-cli/packages/cdk/node_modules/aws-cdk/node_modules/universalify/index.js:8:26)
    at Object.module.exports.makeDir (/Users/anovak/workspace/amazon-genomics-cli/packages/cdk/node_modules/aws-cdk/node_modules/fs-extra/lib/mkdirs/make-dir.js:51:15)
    at Object.defineProperty.value (/Users/anovak/workspace/amazon-genomics-cli/packages/cdk/node_modules/aws-cdk/node_modules/universalify/index.js:36:45)
    at Object.execProgram (/Users/anovak/workspace/amazon-genomics-cli/packages/cdk/node_modules/aws-cdk/lib/api/cxapp/exec.ts:71:12)
    at CloudExecutable.doSynthesize (/Users/anovak/workspace/amazon-genomics-cli/packages/cdk/node_modules/aws-cdk/lib/api/cxapp/cloud-executable.ts:71:24)
    at CloudExecutable.synthesize (/Users/anovak/workspace/amazon-genomics-cli/packages/cdk/node_modules/aws-cdk/lib/api/cxapp/cloud-executable.ts:57:29)
    at CdkToolkit.selectStacksForDeploy (/Users/anovak/workspace/amazon-genomics-cli/packages/cdk/node_modules/aws-cdk/lib/cdk-toolkit.ts:486:22)
    at CdkToolkit.deploy (/Users/anovak/workspace/amazon-genomics-cli/packages/cdk/node_modules/aws-cdk/lib/cdk-toolkit.ts:120:20)
    at initCommandLine (/Users/anovak/workspace/amazon-genomics-cli/packages/cdk/node_modules/aws-cdk/bin/cdk.ts:267:9)

[RyanZim]

If we do this, it should be a single error message with a single stack trace. However, I'm torn on this. I recognize the usefulness of this for debugging, at the same time, callback-based errors do not have stack traces; without universalify, you'd get the same result. Even util.promisify doesn't provide this.