Compiling generated code causes a heap overflow with tsc

[Hilzu]

I'm using ts-proto to generate code from pg_query.proto from libpg_query. With default options compiling the generated code causes tsc to crash due to a heap overflow. Using the --generateTrace option and @typescript/analyze-trace tool this seems to be caused by the fromPartial function for Node message. Using --ts_proto_opt=outputPartialMethods=false fixes the heap overflow.

I have reproduced the issue here: https://github.com/Hilzu/ts-proto-with-pg-query#ts-proto-generated-code-causes-a-heap-overflow-with-tsc

[stephenh]

Hi @Hilzu , if you use --ts_proto_opt=useExactTypes=false, you should be able to keep the from partial methods, but with simpler types, that won't blow up tsc.

Ideally we'd use an Exact type provided by TS: microsoft/TypeScript#12936 but for now we approximate it with a mapped/conditional type that can get expensive.