vpanta/ts_lib_module_root_bug

Example of ts_library module output failing to link

To see the build failures when using the webpack_bundle rule, do the following:

1. Update the MODULE value in module_type.bzl to one of none or commonjs.
2. Execute bazel build //:bundle

What's going on?

As far as I can tell, when using commonjs or none, the generated output should be resolvable by Node itself. The tsc-generated JavaScript in these cases requires based purely on the original import declaration. However, the LinkablePackageInfo does not take into account module_root, so these import attempts fail to resolve (e.g. bazel has made JS module foo available under .../package_foo/src/foo, but mapped package_foo to .../package_foo).

Interestingly, it works fine under module-type umd, as tsc rewrites the import to account for this (e.g. TS referencing foo/foo becomes JS referencing foo/src/foo).