docker: use git tags instead of revs

nixos/tests/docker.nix

@@ -43,7 +43,7 @@ import ./make-test-python.nix ({ pkgs, ...} : {
     docker.fail("sudo -u noprivs docker ps")
     docker.succeed("docker stop sleeping")
 
-    # Must match version twice to ensure client and server versions are correct
-    docker.succeed('[ $(docker version | grep ${pkgs.docker.version} | wc -l) = "2" ]')
+    # Must match version 4 times to ensure client and server git commits and versions are correct
+    docker.succeed('[ $(docker version | grep ${pkgs.docker.version} | wc -l) = "4" ]')
   '';
 })

pkgs/applications/virtualization/docker/default.nix

@@ -184,9 +184,9 @@ rec {
   # Get revisions from
   # https://github.com/docker/docker-ce/tree/${version}/components/engine/hack/dockerfile/install/*
 
-  docker_18_09 = makeOverridable dockerGen {
+  docker_18_09 = makeOverridable dockerGen rec {
     version = "18.09.9";
-    rev = "039a7df9ba8097dd987370782fcdd6ea79b26016";
+    rev = "v${version}";
     sha256 = "0wqhjx9qs96q2jd091wffn3cyv2aslqn2cvpdpgljk8yr9s0yg7h";
     runcRev = "3e425f80a8c931f88e6d94a8c831b9d5aa481657";
     runcSha256 = "18psc830b2rkwml1x6vxngam5b5wi3pj14mw817rshpzy87prspj";
@@ -196,9 +196,9 @@ rec {
     tiniSha256 = "1h20i3wwlbd8x4jr2gz68hgklh0lb0jj7y5xk1wvr8y58fip1rdn";
   };
 
-  docker_19_03 = makeOverridable dockerGen {
+  docker_19_03 = makeOverridable dockerGen rec {
     version = "19.03.12";
-    rev = "48a66213fe1747e8873f849862ff3fb981899fc6";
+    rev = "v${version}";
     sha256 = "0i5xr8q3yjrz5zsjcq63v4g1mzqpingjr1hbf9amk14484i2wkw7";
     runcRev = "dc9208a3303feef5b3839f4323d9beb36df0a9dd"; # v1.0.0-rc10
     runcSha256 = "0pi3rvj585997m4z9ljkxz2z9yxf9p2jr0pmqbqrc7bc95f5hagk";