Patch for module applies with patch command but not composer
It turns out this is an issue with Drupal patches for composer when using an older version of Git.  The problem is with composer-patches 1.6.3.

Three possible solutions for now until the bug gets fixed.

Force 1.6.2

In composer.json, specify 1.6.2:

"require": {
"composer/installers": "^1.0.20",
"cweagans/composer-patches": "1.6.2",


Force git clone with 1.6.3

In composer.json, instead of "dist", use "source":

"config": {
    "preferred-install": "source"
  },


Update git to the latest version