We have been using tracing-hooks to instrument the @langchain/core library. Langchain uses conditional exports in their package.json which translates a package/file being required/imported into a different file path.

tracing-hooks handles this already, but there should be tests to assert that this slightly more complicated use case continues to work. I will create a PR to add these tests.

Acceptance Criteria

• A third test package, pkg-3, is created that has conditional exports and contains both CJS and ESM files.
• A correct InstrumentationConfig is supplied and code transformation works as expected

Example

Imagine a package named test-package with class Foo. It is required/imported as 'test-package/foo'. test-package has conditional exports as described by its package.json:

test-package/package.json:

...
"exports": {
  "./foo": {
    "require": {
        "default": ""./some/other/path/foo.cjs"
      },
      "import": {
        "default": "./some/other/path/foo.js"
      }
  }
}
...

test-package/some/other/path/foo.cjs:

class Foo {
   constructor() {}
   bar() {}
}

module.exports = Foo

test-package/some/other/path/foo.js:

class Foo {
   constructor() {}
   bar() {}
}

export default Foo

The correct InstrumentationConfig should be defined as below and the tests will assert that this works (which it already does in practice).

{
      channelName: 'Foo_bar ',
      module: { name: 'test-package', versionRange: '>=0.0.0', filePath: "some/other/path/foo.js" },
      functionQuery: {
        className: 'Foo',
        methodName: 'bar',
        kind: 'Sync'
      }
}