#!/bin/sh
#
# Parameters: testSubject sourcePath [testScript...]
#
# Run one or more test scripts.  The ${testSubject} is the path of the test
# subject program, and the ${sourcePath} is the path to the top level of the
# source directory.  If any ${testScript} parameters are given, they are the
# tests to run (each one being either the full path to a script, or the base
# filename of the script in the test directory).  If no test scripts are
# listed, then all tests directly under "${sourcePath}/tests/" are run.
#
# Test scripts should be written to exit 0 if the test passed, 2 if the test
# is to be skipped, or any other exit status to indicate failure.  They are
# run via "sh -e", so any command exiting non-zero will cause the test
# script to exit early.
#
# The test scripts can rely on the environment variables "testSubject",
# "sourcePath", "workFile1", "workFile2", "workFile3", and "workFile4" being
# populated, and should use those work files - which will be present and
# empty - for scratch space.  They should not delete those files.
#
# When the test scripts are called, LANG and LC_ALL are set to "C".
#
# Anything output by a test script on stdout or stderr is captured and shown
# after the "OK" / "FAILED" / "skipped" result description.
#
# The exit status of this script will be 1 if any test failed, 0 otherwise. 
# A skipped test is not counted as a failure.
#

testSubject="$1"
sourcePath="$2"
shift
shift
selectedTests="$*"

# Temporary working files, for the test scripts to use.
workFile1=$(mktemp 2>/dev/null) || workFile1="./.tmp1"
workFile2=$(mktemp 2>/dev/null) || workFile2="./.tmp2"
workFile3=$(mktemp 2>/dev/null) || workFile3="./.tmp3"
workFile4=$(mktemp 2>/dev/null) || workFile4="./.tmp4"

# Clean up the temporary files on exit, in case we are interrupted.
trap 'rm -f "${workFile1}" "${workFile2}" "${workFile3}" "${workFile4}"' EXIT

# Variables used by the test scripts.
export testSubject sourcePath workFile1 workFile2 workFile3 workFile4

# Set everything to the "C" locale.
LANG=C
LC_ALL=C
export LANG LC_ALL

# If no tests were specified, list all test scripts under the source path.
test -n "${selectedTests}" || selectedTests=$(find "${sourcePath}/tests" -maxdepth 1 -type f | sort -n)

# Initial pass to count the number of tests and find the length of the
# longest test name, to use when formatting the output.
#
numberOfTests=0
maxTestNameLength=0
for testScript in ${selectedTests}; do
	# Find the test script, make sure it exists.
	test -f "${testScript}" || testScript="${sourcePath}/tests/${testScript}"
	test -f "${testScript}" || testScript=$(find "${sourcePath}/tests" -maxdepth 1 -type f -name "${testScript##*/}*" | sed -n '1p')
	test -f "${testScript}" || continue

	numberOfTests=$((1+numberOfTests))

	testScriptLeaf="${testScript##*/}"
	testName="$(echo "${testScriptLeaf%.sh}" | tr '_' ' ' | sed 's/ - /: /')"
	testNameLength=${#testName}
	test "${testNameLength}" -gt "${maxTestNameLength}" && maxTestNameLength="${testNameLength}"
done

# Set a minimum and maximum test name length.
test "${maxTestNameLength}" -lt 10 && maxTestNameLength=10
test "${maxTestNameLength}" -gt 60 && maxTestNameLength=60

# Count the number of digits in the number of tests so we know how wide the
# column for the test count should be.
testCountWidth=${#numberOfTests}

# The exit status - 0 means all tests that were run have passed, 1 means
# that at least one test failed.
overallExitStatus=0

# Run all of the selected test scripts, formatting the output.
#
testNumber=0
for testScript in ${selectedTests}; do
	# Find the test script, make sure it exists.
	test -f "${testScript}" || testScript="${sourcePath}/tests/${testScript}"
	test -f "${testScript}" || testScript=$(find "${sourcePath}/tests" -maxdepth 1 -type f -name "${testScript##*/}*" | sed -n '1p')
	test -f "${testScript}" || continue

	testNumber=$((1+testNumber))

	testScriptLeaf="${testScript##*/}"
	testName="$(echo "${testScriptLeaf%.sh}" | tr '_' ' ' | sed 's/ - /: /')"
	printf "%${testCountWidth}d/%d: %-${maxTestNameLength}.${maxTestNameLength}s  " "${testNumber}" "${numberOfTests}"  "${testName}"

	# Run the test script, capturing the output and the exit status.
	testExitStatus=0
	testOutput=""
	if test -s "${testScript}"; then
		true > "${workFile1}"
		true > "${workFile2}"
		true > "${workFile3}"
		true > "${workFile4}"
		testOutput=$(sh -e "${testScript}" 2>&1)
		testExitStatus=$?
	else
		testOutput="test script has not yet been written"
		testExitStatus=2
	fi

	# Work out what we're going to say about this test result.
	testResultDescription=""
	resultFormatCodes=""
	if test ${testExitStatus} -eq 0; then
		resultFormatCodes="setaf 2;bold"
		testResultDescription="OK"
	elif test ${testExitStatus} -eq 2; then
		resultFormatCodes="setaf 3"
		testResultDescription="skipped"
	else
		resultFormatCodes="setaf 1;bold"
		testResultDescription="FAILED"
		overallExitStatus=1
	fi

	# If stdout is not a terminal, don't use terminal format codes.
	test -t 1 || resultFormatCodes=""

	# Show the description of the test result, and start a new line.
	test -n "${resultFormatCodes}" && command -v tput >/dev/null 2>&1 && echo "${resultFormatCodes}" | tr ';' '\n' | tput -S 2>/dev/null
	printf "%s" "${testResultDescription}"
	test -n "${resultFormatCodes}" && command -v tput >/dev/null 2>&1 && tput sgr0 2>/dev/null
	printf "\n"

	# If there was any output from the test, display it on the new line,
	# with the same terminal format codes as the result description, and
	# each line prefixed with the test number.
	if test -n "${testOutput}"; then
		test -n "${resultFormatCodes}" && command -v tput >/dev/null 2>&1 && echo "${resultFormatCodes}" | tr ';' '\n' | tput -S 2>/dev/null
		printf "%s" "$(echo "${testOutput}" | sed "s,^,$(printf "%${testCountWidth}d/%d: - " "${testNumber}" "${numberOfTests}"),")"
		test -n "${resultFormatCodes}" && command -v tput >/dev/null 2>&1 && tput sgr0 2>/dev/null
		printf "\n"
	fi
done

# Clean up.
rm -f "${workFile1}" "${workFile2}" "${workFile3}" "${workFile4}"
trap '' EXIT

# Exit with status 1 if any test failed outright, 0 otherwise.
exit ${overallExitStatus}

# EOF