cdktf synth fails when outdir is set in AppOptions instead of the CLI flag

TL;DR

Do not pass outdir to the App constructor for real runs; it is only for testing. Set the output directory with cdktf synth -o [dir], the CDKTF_OUTDIR env var, or the output property in cdktf.json.

The error

Setting outdir in AppOptions (e.g. new App({ outdir: "my-dir" })) and running cdktf synth raises a synth error instead of writing output to that directory.

Fix it

1. Remove outdir from the App constructor in your code; keep new App() plain (or with only testing-related options).

2. Pick one of the supported ways to set the output directory:

   • CLI flag: cdktf synth -o my-dir (or --output my-dir)
   • Environment variable: export CDKTF_OUTDIR=my-dir
   • Config file: set "output": "my-dir" in cdktf.json
3. Re-run cdktf synth and confirm output lands in the chosen directory.

Expected result: synth completes and cdk.tf.json appears under the configured output directory.

When to use this

• You set outdir in App/AppOptions and synth errors out
• You want the synth output in a non-default directory

When NOT to use this

• Synth fails for other reasons (missing provider, bad import) with outdir untouched
• You are writing unit tests for stacks (the in-code outdir is intended for that)

Root cause

The CDKTF CLI spawns your app as a separate process and there is no channel for the app to tell the CLI which outdir it chose, so the CLI cannot find the generated Terraform config afterward. By design the outdir must come from the CLI side (flag, env var, or cdktf.json). The in-code option exists only so tests can synthesize to a temp directory without a CLI.

Edge cases

• cdktf.json output and CDKTF_OUTDIR can disagree; the CLI flag wins when several are set.
• Relative outdir paths resolve against the project root, not the stack file location.