Add scripts to run tests in Docker

Author: ErikSchierboom

.dockerignore

@@ -5,3 +5,7 @@
 .gitattributes
 .dockerignore
 Dockerfile
+bin/run-in-docker.sh
+bin/run-tests-in-docker.sh
+bin/run-tests.sh
+test/

bin/run-tests-in-docker.sh

@@ -0,0 +1,31 @@
+#!/usr/bin/env sh
+
+# Synopsis:
+# Test the test runner Docker image by running it against a predefined set of 
+# solutions with an expected output.
+# The test runner Docker image is built automatically.
+
+# Output:
+# Outputs the diff of the expected test results against the actual test results
+# generated by the test runner Docker image.
+
+# Example:
+# ./bin/run-tests-in-docker.sh
+
+# Stop executing when a command returns a non-zero return code
+set -e
+
+# Build the Docker image
+docker build --rm -t exercism/python-test-runner .
+
+# Run the Docker image using the settings mimicking the production environment
+docker run \
+    --rm \
+    --network none \
+    --read-only \
+    --mount type=bind,src="${PWD}/test",dst=/opt/test-runner/test \
+    --mount type=volume,dst=/tmp \
+    --volume "${PWD}/bin/run-tests.sh:/opt/test-runner/bin/run-tests.sh" \
+    --workdir /opt/test-runner \
+    --entrypoint /opt/test-runner/bin/run-tests.sh \
+    exercism/python-test-runner

bin/run-tests.sh

@@ -0,0 +1,47 @@
+#!/usr/bin/env sh
+
+# Synopsis:
+# Test the test runner by running it against a predefined set of solutions 
+# with an expected output.
+
+# Output:
+# Outputs the diff of the expected test results against the actual test results
+# generated by the test runner.
+
+# Example:
+# ./bin/run-tests.sh
+
+exit_code=0
+
+# Iterate over all test directories
+for test_dir in test/*; do
+    if [ ! -d "${test_dir}" ]; then
+        continue
+    fi
+
+    test_dir_name=$(basename "${test_dir}")
+    test_dir_path=$(realpath "${test_dir}")
+    output_dir_path=$(mktemp -d -t 'test-runner-tests-XXXXXXXXX')
+    results_file_path="${output_dir_path}/results.json"
+    expected_results_file_path="${test_dir_path}/results.json"
+
+    bin/run.sh "${test_dir_name}" "${test_dir_path}" "${output_dir_path}"
+
+    # OPTIONAL: Normalize the results file
+    # If the results.json file contains information that changes between 
+    # different test runs (e.g. timing information or paths), you should normalize
+    # the results file to allow the diff comparison below to work as expected
+    # sed -i -E \
+    #   -e 's/Elapsed time: [0-9]+\.[0-9]+ seconds//g' \
+    #   -e "s~${test_dir_path}~/solution~g" \
+    #   "${results_file_path}"
+
+    echo "${test_dir_name}: comparing results.json to expected_results.json"
+    diff "${results_file_path}" "${expected_results_file_path}"
+
+    if [ $? -ne 0 ]; then
+        exit_code=1
+    fi
+done
+
+exit ${exit_code}