allow setting nixpkgs path via env var

Author: erikarvstedt

check-compatibilities.sh

@@ -2,9 +2,9 @@
 set -euo pipefail
 
 versionsFile=changes-8e18c70.json
-nixpkgsPath=/path/to/nixpkgs
+nixpkgsPath=${NIXPKGS_PATH:-}
 if [[ ! -e $nixpkgsPath ]]; then
-    echo "Please set nixpkgsPath"
+    echo "Please set NIXPKGS_PATH"
     exit 1
 fi
 if ! git -C "$nixpkgsPath" diff --quiet; then

get-revisions.rb

@@ -3,12 +3,10 @@
 require 'open3'
 require 'json'
 
-NixpkgsPath = File.expand_path("/path/to/nixpkgs")
+NixpkgsPath = File.expand_path(ENV['NIXPKGS_PATH'] || (raise 'Please set NIXPKGS_PATH'))
 # master as of 2021-10-25
 StartRev = "8e18c70837aa01ade3718cd0fd35b649b3a2cf52"
 
-raise 'Please set NixpkgsPath' unless Dir.exist? NixpkgsPath
-
 Change = Struct.new(:version, :drv, :date, :rev, :depth, keyword_init: true)
 
 def find_versions(versions_to_find: 10, start_depth: 0, log: Log.new)