ts-node >= 7.x makes mocha unit tests hanging

[Q-Man]

I'm using Mocha Version 6.0.2 in my project with ts-node for writing unit tests in TypeScript.

I'm starting mocha from the command line via:

mocha --require ts-node/register --ui bdd ./src/**/*.test.ts ./src/**/*.test.tsx

With ts-node 6.x I don't have any problems, but all ts-node versions after (7.x and 8.x) make mocha hanging without any output.

Is it possible to get a debug output from Mocha or ts-node to see what's going on?

[hisuwh]

I'm seeing the same thing with alsatian tests with ts-node 8.x but not with 7.0.1

[jbouhier]

Duplicate of #754.

For now --transpile-only with the CLI should help.
See https://github.com/TypeStrong/ts-node#cli-and-programmatic-options.

[cspotcode]

Closing because each aspect of this ticket is either solved or the necessary work is tracked by other issues:

• Performance recommendations here: https://typestrong.org/ts-node/docs/performance
• Use ts-node with TypeScript incremental build #817, Make --files default? Conditionally when leveraging incremental compilation? #1245, Refactor fs (cache/tracing) layer into self-contained API #1161 track research and work to use incremental builds
• TS_NODE_DEBUG=true logs verbose diagnostic information to see what ts-node and the compiler are doing
  • Docs: https://typestrong.org/ts-node/docs/options#diagnostics