Review GitHub issue #90 for DDEV project

[bserem]

Fixes #90

The post-install script was failing when DDEV_UPSTREAM_PROVIDER was not defined in the .env file. The script uses 'set -u' flag (via pipefail) which treats unset variables as errors.

Changed the conditional check from '$DDEV_UPSTREAM_PROVIDER' to '${DDEV_UPSTREAM_PROVIDER:-}' to use parameter expansion that provides an empty string if the variable is unset, preventing the script from failing when the variable doesn't exist.

Summary

• Fixes post-install action fails on 2.1.0-beta1 #90: post-install action fails on MacOS with "DDEV_UPSTREAM_PROVIDER: unbound variable" error
• Changed variable reference from $DDEV_UPSTREAM_PROVIDER to ${DDEV_UPSTREAM_PROVIDER:-} to safely handle unset variables

Problem

The post-install script in install.yaml was failing on MacOS when the DDEV_UPSTREAM_PROVIDER variable was not defined in the .env file. The script uses bash's -u flag (treat unset variables as errors), which caused the script to exit immediately when trying to reference the undefined variable, even though it was inside a conditional check.

Solution

Used parameter expansion syntax ${DDEV_UPSTREAM_PROVIDER:-} which provides an empty string if the variable is unset, allowing the conditional check to work properly without triggering an unbound variable error.

Test Plan

• Code change made in install.yaml:138
• Test installation on MacOS without DDEV_UPSTREAM_PROVIDER in .env file
• Test installation on MacOS with DDEV_UPSTREAM_PROVIDER in .env file
• Verify migration from old .env to .env.anner works when variable is set