add self-test for calc_release_version.py

Author: rcsanchez97

etc/calc_release_version.py

@@ -22,6 +22,18 @@
 current Git commit.
 """
 
+# XXX NOTE XXX NOTE XXX NOTE XXX
+# After modifying this script it is advisable to execute the self-test.
+#
+# This is done by starting in the directory containing this script and then
+# executing a separate self-test script, like this:
+#
+# $ bash ./calc_release_version_selftest.sh
+#
+# The self-test script will emit diagnostic output. If tracing of the execution
+# of each command is desired, then add the -x option to the bash invocation.
+# XXX NOTE XXX NOTE XXX NOTE XXX
+
 import datetime
 import re
 import subprocess

etc/calc_release_version_selftest.sh

@@ -0,0 +1,73 @@
+#!/bin/bash
+# calc_release_version_selftest.sh is used to test output of calc_release_version.py.
+# run with:
+# cd etc
+# ./calc_release_version_selftest.sh
+
+set -o errexit
+set -o pipefail
+
+function assert_eq () {
+    a="$1"
+    b="$2"
+    if [[ "$a" != "$b" ]]; then
+        echo "Assertion failed: $a != $b"
+        # Print caller
+        caller
+        exit 1
+    fi
+}
+
+SAVED_REF=$(git rev-parse HEAD)
+
+function cleanup () {
+    [[ -e calc_release_version_test.py ]] && rm calc_release_version_test.py
+    git checkout $SAVED_REF --quiet
+}
+
+trap cleanup EXIT
+
+: ${PYTHON_INTERP:=python}
+if [[ -z $(command -v "${PYTHON_INTERP}") ]]; then
+    echo "Python interpreter '${PYTHON_INTERP}' is not valid."
+    echo "Set the PYTHON_INTERP environment variable to a valid interpreter."
+    exit 1
+fi
+
+# copy calc_release_version.py to a separate file not tracked by git so it does not change on `git checkout`
+cp calc_release_version.py calc_release_version_test.py
+
+echo "Test a tagged commit ... begin"
+{
+    git checkout r3.7.2 --quiet
+    got=$("${PYTHON_INTERP}" calc_release_version_test.py)
+    assert_eq "$got" "3.7.2"
+    git checkout - --quiet
+}
+echo "Test a tagged commit ... end"
+
+DATE=$(date +%Y%m%d)
+echo "Test an untagged commit ... begin"
+{
+    # 15756bff8640435b8647fe2eccf8d9c1f6d78816 is commit before r3.7.2
+    git checkout 15756bff8640435b8647fe2eccf8d9c1f6d78816 --quiet
+    got=$("${PYTHON_INTERP}" calc_release_version_test.py)
+    assert_eq "$got" "3.7.2-$DATE+git15756bff86"
+    git checkout - --quiet
+}
+echo "Test an untagged commit ... end"
+
+echo "Test next minor version ... begin"
+{
+    CURRENT_SHORTREF=$(git rev-parse --revs-only --short=10 HEAD)
+    got=$("${PYTHON_INTERP}" calc_release_version_test.py --next-minor)
+    # XXX NOTE XXX NOTE XXX
+    # If you find yourself looking at this line because the assertion below
+    # failed, then it is probably because a new major/minor release was made.
+    # Update the expected output to represent the correct next version.
+    # XXX NOTE XXX NOTE XXX
+    assert_eq "$got" "3.9.0-$DATE+git$CURRENT_SHORTREF"
+}
+echo "Test next minor version ... end"
+
+echo "All tests passed"