Add a partial test for geoip (#902)

.github/workflows/test.yml

@@ -44,6 +44,7 @@ jobs:
         run: |
           ./create-docker-volumes-test.sh
           ./relay-credentials-test.sh
+          ./geoip-test.sh
 
       - name: Inspect failure
         if: failure()

install/_test_setup.sh

@@ -14,19 +14,17 @@ teardown() {
 }
 
 setup() {
-  # Clone the local repo into a temp dir, and propagate local changes.
-
-  # FWIW `git clone --local` breaks for me because it depends on hard-linking,
-  # which doesn't work across devices, and I happen to have my workspace and
-  # tmp on separate devices.
+  # Clone the local repo into a temp dir. FWIW `git clone --local` breaks for
+  # me because it depends on hard-linking, which doesn't work across devices,
+  # and I happen to have my workspace and /tmp on separate devices.
   git clone --depth=1 "file://$(pwd)" "$_SANDBOX"
 
+  # Now propagate any local changes from the working copy to the sandbox. This
+  # provides a pretty nice dev experience: edit the files in the working copy,
+  # then run `DEBUG=1 some-test.sh` to leave the sandbox up for interactive
+  # dev/debugging.
   git status --porcelain | while read line; do
-
-    # $line here is something like `M some-script.sh`. By propagating working
-    # copy changes to the sandbox, we can provide a pretty nice dev experience:
-    # edit the files in the working copy, then run `DEBUG=1 some-test.sh` to
-    # leave the sandbox up for interactive dev/debugging.
+    # $line here is something like `M some-script.sh`.
 
     local filepath="$(cut -f2 -d' ' <(echo $line))"
     local filestatus="$(cut -f1 -d' ' <(echo $line))"

install/geoip-test.sh

@@ -0,0 +1,16 @@
+#!/usr/bin/env bash
+source "$(dirname $0)/_test_setup.sh"
+
+mmdb="geoip/GeoLite2-City.mmdb"
+
+# Starts with no mmdb, ends up with empty.
+test ! -f $mmdb
+./install/geoip.sh
+diff -rub $mmdb $mmdb.empty
+
+# Doesn't clobber existing, though.
+echo GARBAGE > $mmdb
+./install/geoip.sh
+test "$(cat $mmdb)" = "GARBAGE"
+
+report_success