Digging deeper I'm seeing this, but can't figure out what's happening here:

exceptionDetails: {
        exceptionId: 2,
        text: 'Uncaught',
        lineNumber: 0,
        columnNumber: 27,
        scriptId: '2434',
        exception: {
          type: 'object',
          subtype: 'error',
          className: 'TypeError',
          description: "TypeError: Cannot read property 'id1' of undefined\n" +
            '    at <anonymous>:1:28\n' +
            '    at <http://Session.post|Session.post> (inspector.js:110:28)\n' +
            '    at internal/util.js:278:30\n' +
            '    at new Promise (<anonymous>)\n' +
            '    at <http://Session.post|Session.post> (internal/util.js:277:12)\n' +
            '    at /opt/pulumi/node_modules/@pulumi/pulumi/runtime/closure/v8_v11andHigher.js:121:40\n' +
            '    at Generator.next (<anonymous>)\n' +
            '    at fulfilled (/opt/pulumi/node_modules/@pulumi/pulumi/runtime/closure/v8_v11andHigher.js:18:58)\n' +
            '    at processTicksAndRejections (internal/process/task_queues.js:93:5)',
          objectId: '{"injectedScriptId":1,"id":4}'
        }

i have a hunch that this has something to do with how jest sets up a vm and possibly messing with or restricting the global namespace somehow

i've found that if i poke the jest global settings (like inserting

__inflightFunctions

via the "globals" configuration) I get different errors.

but i don't really know what i'm doing

Are you using “closure serialization” (magic functions) anywhere in your code?

I believe both lambdacallbacks and dynamic resources use this, right?

Will look into this a little later - there are some hints in the call stack about what might be interacting poorly with Jest. Haven’t seen anything like this previously though.

I created a minimal repo and opened an issue: https://github.com/pulumi/pulumi/issues/3799