skaffold pre-build hook can't create input

Expected behavior

My understanding of the before-build hook was that it should be able to create the inputs used for the build.

Actual behavior

Dependency checking happens before the before-build hook is run and fails as it can't find the data that hasn't been created yet.

Information

• skaffold v1.35.2
• Operating system: Ubuntu 18.04
• Contents of skaffold.yaml:

apiVersion: skaffold/v2beta22
kind: Config
build:
  artifacts:
  - image: makedataimage
    hooks:
      before:
      - command: ["./makedata.sh"]

makedata.sh

#!/bin/bash

echo "XX" > data

Dockerfile

FROM busybox

COPY ./data .

Steps to reproduce the behavior

skaffold build

Generating tags...
 - makedataimage -> makedataimage:latest
Some taggers failed. Rerun with -vdebug for errors.
Checking cache...
 - makedataimage: Error checking cache.
getting hash for artifact "makedataimage": getting dependencies for "makedataimage": file pattern [./data] must match at least one file