Workaround issue with .editorconfigs when NUGET_PACKAGES does not have a

trailing slash

build.sh

@@ -13,4 +13,5 @@ while [[ -h $source ]]; do
 done
 
 scriptroot="$( cd -P "$( dirname "$source" )" && pwd )"
+. "$scriptroot/eng/nuget-workaround.sh" $@
 "$scriptroot/eng/common/build.sh" --restore --build --pack $@

eng/cibuild.sh

@@ -13,4 +13,5 @@ while [[ -h $source ]]; do
 done
 scriptroot="$( cd -P "$( dirname "$source" )" && pwd )"
 
+. "$scriptroot/nuget-workaround.sh" $@
 . "$scriptroot/common/build.sh" --ci $@

eng/nuget-workaround.sh

@@ -0,0 +1,30 @@
+#!/usr/bin/env bash
+
+# This works around an issue where .editorconfigs in nuget packages are not respected if the NUGET_PACKAGES
+# environment variable does not end with a slash.  We copy the logic for setting the NUGET_PACKAGES variable from the eng/common/tools.sh
+# script as we cannot modify the script itself (its arcade managed).
+# This workaround is only required for non-windows builds as the powershell versions of the arcade scripts already ensure a trailing slash is present.
+# Tracking https://github.com/dotnet/roslyn/issues/72657
+ci=false
+while [[ $# > 0 ]]; do
+  opt="$(echo "${1/#--/-}" | tr "[:upper:]" "[:lower:]")"
+  case "$opt" in
+    -ci)
+      ci=true
+      break
+      ;;
+    *)
+      shift
+      ;;
+  esac
+done
+if [[ "$ci" == true ]]; then
+  if [[ -z ${NUGET_PACKAGES:-} ]]; then
+    if [[ "$ci" == true ]]; then
+      export NUGET_PACKAGES="$HOME/.nuget/packages/"
+    else
+      export NUGET_PACKAGES="$repo_root/.packages/"
+      export RESTORENOCACHE=true
+    fi
+  fi
+fi