# grepTest.cmake executes a command and captures the output in a file. File is then compared
# against a reference file. Exit status of command can also be compared.

# arguments checking
if (NOT TEST_PROGRAM)
  message (FATAL_ERROR "Require TEST_PROGRAM to be defined")
endif (NOT TEST_PROGRAM)
#if (NOT TEST_ARGS)
#  message (STATUS "Require TEST_ARGS to be defined")
#endif (NOT TEST_ARGS)
if (NOT TEST_FOLDER)
  message ( FATAL_ERROR "Require TEST_FOLDER to be defined")
endif (NOT TEST_FOLDER)
if (NOT TEST_OUTPUT)
  message (FATAL_ERROR "Require TEST_OUTPUT to be defined")
endif (NOT TEST_OUTPUT)
#if (NOT TEST_EXPECT)
#  message (STATUS "Require TEST_EXPECT to be defined")
#endif (NOT TEST_EXPECT)
if (NOT TEST_FILTER)
  message (STATUS "Require TEST_FILTER to be defined")
endif (NOT TEST_FILTER)
if (NOT TEST_REFERENCE)
  message (FATAL_ERROR "Require TEST_REFERENCE to be defined")
endif (NOT TEST_REFERENCE)

message (STATUS "COMMAND: ${TEST_PROGRAM} ${TEST_ARGS}")

# run the test program, capture the stdout/stderr and the result var
EXECUTE_PROCESS (
    COMMAND ${TEST_PROGRAM} ${TEST_ARGS}
    WORKING_DIRECTORY ${TEST_FOLDER}
    RESULT_VARIABLE TEST_RESULT
    OUTPUT_FILE ${TEST_OUTPUT}
    ERROR_FILE ${TEST_OUTPUT}.err
    OUTPUT_VARIABLE TEST_ERROR
    ERROR_VARIABLE TEST_ERROR
)

message (STATUS "COMMAND Result: ${TEST_RESULT}")
message (STATUS "COMMAND Error: ${TEST_ERROR}")

# now grep the output with the reference
file (READ ${TEST_FOLDER}/${TEST_OUTPUT} TEST_STREAM)

# TEST_REFERENCE should always be matched
STRING(REGEX MATCH "${TEST_REFERENCE}" TEST_MATCH ${TEST_STREAM}) 
STRING(COMPARE EQUAL "${TEST_REFERENCE}" "${TEST_MATCH}" TEST_RESULT) 
if (${TEST_RESULT} STREQUAL "0")
  message (FATAL_ERROR "Failed: The output of ${TEST_PROGRAM} did not contain ${TEST_REFERENCE}")
endif (${TEST_RESULT} STREQUAL "0")

STRING(REGEX MATCH "${TEST_FILTER}" TEST_MATCH ${TEST_STREAM}) 
if (${TEST_EXPECT} STREQUAL "1")
  # TEST_EXPECT (1) interperts TEST_FILTER as NOT to match
  STRING(LENGTH "${TEST_MATCH}" TEST_RESULT) 
  if (NOT ${TEST_RESULT} STREQUAL "0")
    message (FATAL_ERROR "Failed: The output of ${TEST_PROGRAM} did contain ${TEST_FILTER}")
  endif (NOT ${TEST_RESULT} STREQUAL "0")
endif (${TEST_EXPECT} STREQUAL "1")

# everything went fine...
message ("Passed: The output of ${TEST_PROGRAM} matched")