diff --git a/README.md b/README.md
index d3e39b1..27074e2 100644
--- a/README.md
+++ b/README.md
@@ -32,14 +32,25 @@ In order to generate GET forms add `'type' => 'GET'` to the `filterForm()` or `b
 
 ## Testing
 
+To run PHPUnit tests:
+
+```shell
+Test/phpunit.sh <args>
+```
+
+Execute shell for manual testing
+
 ```shell
-docker pull devkba/cake2-app-template:staging;
+docker pull devkba/cake2-app-template:staging
 docker run \
     --rm \
+    --init \
     -it \
     -v "$(pwd)":/cakephp-filter-plugin \
     -e DEBUG=0 \
-    devkba/cake2-app-template:staging /cakephp-filter-plugin/Test/test.sh
+    -e BEFORE_SCRIPT="/cakephp-filter-plugin/Test/before_script.sh" \
+    -e AFTER_SCRIPT="/cakephp-filter-plugin/Test/after_script.sh" \
+    devkba/cake2-app-template:staging
 ```
 
 ## Contributing
diff --git a/Test/after_script.sh b/Test/after_script.sh
new file mode 100755
index 0000000..3c60c71
--- /dev/null
+++ b/Test/after_script.sh
@@ -0,0 +1,3 @@
+#!/usr/bin/env sh
+# stop mysql service at the end of the tests
+service mysql stop
diff --git a/Test/test.sh b/Test/before_script.sh
similarity index 69%
rename from Test/test.sh
rename to Test/before_script.sh
index 00da225..a92cd29 100755
--- a/Test/test.sh
+++ b/Test/before_script.sh
@@ -9,15 +9,3 @@ composer config repositories.cakephp-filter-plugin '{"type": "path", "url": "/ca
 composer config repo.packagist false
 # require the current dev version of the filter plugin
 composer require --prefer-source kba-team/cakephp-filter-plugin:@dev
-# Either use the test case from the parameter, or run all tests
-if [ -n "${1}" ]; then
-    # call PHPUnit and remember return code
-    vendor/bin/phpunit ${*}
-    E=$?
-else
-    (>&2 echo "ERROR: Missing test case!")
-fi
-# stop mysql service at the end of the tests
-service mysql stop
-# exit with the return code of phpunit
-exit $E
diff --git a/Test/phpunit.sh b/Test/phpunit.sh
new file mode 100755
index 0000000..cc7cb3a
--- /dev/null
+++ b/Test/phpunit.sh
@@ -0,0 +1,31 @@
+#!/usr/bin/env bash
+# the docker image to use for phpunit testing
+DOCKER_IMAGE="devkba/cake2-app-template:staging"
+# the path to prepend to the test case
+TEST_PREFIX="Plugin/Filter/"
+# compile PHPUnit parameters
+PARAMS=""
+for arg in "$@"; do
+    # add prefix in case an argument is a path to a test
+    if [[ "${arg}" == *Test.php ]]; then
+        arg="${TEST_PREFIX}${arg}"
+    fi
+    # in case this is the first argument, don't add $IFS
+    if [ "${PARAMS}" == "" ]; then
+        PARAMS="${arg}"
+    else
+        PARAMS="${PARAMS}${IFS}${arg}"
+    fi
+done
+# pull latest docker image
+docker pull "${DOCKER_IMAGE}" || exit $?
+# run actual PHPUnit inside docker container
+docker run \
+    --rm \
+    --init \
+    -it \
+    -v "$(pwd)":/cakephp-filter-plugin \
+    -e DEBUG=0 \
+    -e BEFORE_SCRIPT="/cakephp-filter-plugin/Test/before_script.sh" \
+    -e AFTER_SCRIPT="/cakephp-filter-plugin/Test/after_script.sh" \
+    "${DOCKER_IMAGE}" vendor/bin/phpunit ${PARAMS}