@@ -219,7 +219,8 @@ function disable_python3_package {

 # Wrapper for ``pip install`` to set cache and proxy environment variables

 # Uses globals ``OFFLINE``, ``PIP_VIRTUAL_ENV``,

 # ``PIP_UPGRADE``, ``TRACK_DEPENDS``, ``*_proxy``,

-# pip_install package [package ...]

+# Usage:

+#  pip_install pip_arguments

 function pip_install {

     local xtrace result

     xtrace=$(set +o | grep xtrace)

@@ -241,6 +242,26 @@ function pip_install {

     if [[ -z "$os_PACKAGE" ]]; then

         GetOSVersion

     fi

+

+    # Try to extract the path of the package we are installing into

+    # package_dir.  We need this to check for test-requirements.txt,

+    # at least.

+    #

+    # ${!#} expands to the last positional argument to this function.

+    # With "extras" syntax included, our arguments might be something

+    # like:

+    #  -e /path/to/fooproject[extra]

+    # Thus this magic line grabs just the path without extras

+    #

+    # Note that this makes no sense if this is a pypi (rather than

+    # local path) install; ergo you must check this path exists before

+    # use.  Also, if we had multiple or mixed installs, we would also

+    # likely break.  But for historical reasons, it's basically only

+    # the other wrapper functions in here calling this to install

+    # local packages, and they do so with single call per install.  So

+    # this works (for now...)

+    local package_dir=${!#%\[*\]}

+

     if [[ $TRACK_DEPENDS = True && ! "$@" =~ virtualenv ]]; then

         # TRACK_DEPENDS=True installation creates a circular dependency when

         # we attempt to install virtualenv into a virtualenv, so we must global

@@ -261,7 +282,6 @@ function pip_install {

                 # versions supported, and if we find the version of

                 # python3 we've been told to use, use that instead of the

                 # default pip

-                local package_dir=${!#}

                 local python_versions

                 # Special case some services that have experimental

@@ -323,7 +343,7 @@ function pip_install {

     # Also install test requirements

     local install_test_reqs=""

-    local test_req="${!#}/test-requirements.txt"

+    local test_req="${package_dir}/test-requirements.txt"

     if [[ -e "$test_req" ]]; then

         install_test_reqs="-r $test_req"

     fi