#! /usr/bin/python

"""This script takes the file produced by DMD's test mode and checks its
correctness.

It produces the following output files: $TMP/test-{fixed,filtered,diff}.dmd.

It runs the appropriate fix* script to get nice stack traces.  It also
filters out platform-specific details from the test output file.

Note: you must run this from the same directory that you invoked DMD's test
mode, otherwise the fix* script will not work properly, because some of the
paths in the test output are relative.

"""

from __future__ import print_function

import os
import platform
import re
import subprocess
import sys
import tempfile


def main():

    # Arguments

    if (len(sys.argv) != 3):
        print("usage:", sys.argv[0], "<srcdir> <test-output>")
        sys.exit(1)

    srcdir = sys.argv[1]

    # Filenames

    tempdir = tempfile.gettempdir()
    in_name       = sys.argv[2]
    fixed_name    = tempdir + os.sep + "test-fixed.dmd"
    filtered_name = tempdir + os.sep + "test-filtered.dmd"
    diff_name     = tempdir + os.sep + "test-diff.dmd"
    expected_name = srcdir + os.sep + \
                    "memory/replace/dmd/test-expected.dmd"

    # Fix stack traces

    print("fixing output to", fixed_name)

    sysname = platform.system()
    if sysname == "Linux":
        fix = srcdir + os.sep + "tools/rb/fix-linux-stack.pl"
    elif sysname == "Darwin":
        fix = srcdir + os.sep + "tools/rb/fix_macosx_stack.py"
    else:
        print("unhandled platform: " + sysname, file=sys.stderr)
        sys.exit(1)

    subprocess.call(fix, stdin=open(in_name, "r"),
                         stdout=open(fixed_name, "w"))

    # Filter output

    # In stack trace records we filter out all stack frames that contain a
    # function whose name doesn't begin with "RunTestMode".  And the remaining
    # ones have their line numbers omitted, unfortunately, because they are
    # often off by one or two and this can vary between builds (e.g. debug vs
    # non-debug).
    #
    # As for stack frame records, we complete eliminate all those that contain
    # a function whose name doesn't begin with "RunTestMode", because such
    # stack frame records are highly dependent on the exact forms of stack
    # traces.

    print("filtering output to", filtered_name)

    with open(fixed_name, "r") as fin, \
         open(filtered_name, "w") as fout:

        test_frame_re = re.compile(r".*(RunTestMode\w*).*(DMD.cpp)")

        for line in fin:
            if re.match(r" (Allocated at|Reported( again)? at)", line):
                # It's a stack trace record.
                print(line, end='', file=fout)

                # Filter the stack trace -- only show RunTestMode* frames.
                for frame in fin:
                    if re.match(r"   ", frame):
                        m = test_frame_re.match(frame)
                        if m:
                            print("   ...", m.group(1), "...", m.group(2),
                                  file=fout)
                    else:
                        # We're past the stack trace.
                        print(frame, end='', file=fout)
                        break

            elif re.search("in stack frame record", line):
                # Stack frame record.  Get the whole thing (we know how many
                # lines it has).
                line2 = fin.next()
                line3 = fin.next()
                line4 = fin.next()
                frame = fin.next()
                line6 = fin.next()
                m = test_frame_re.match(frame)
                if m:
                    # This is a stack frame record from RunTestMode* -- print
                    # it, obscuring record numbers (which vary unpredictably).
                    print(re.sub(r"record \d+ of \d+", "record M of N", line),
                          end='', file=fout)
                    print(line2, end='', file=fout)
                    print(line3, end='', file=fout)
                    print(line4, end='', file=fout)
                    print("   ...", m.group(1), "...", m.group(2), file=fout)
                    print(line6, end='', file=fout)

            else:
                # Some line that needs no special handling.  Copy it through.
                print(line, end='', file=fout)

    # Compare with expected output

    print("diffing output to", diff_name)

    ret = subprocess.call(["diff", "-u", filtered_name, expected_name],
                          stdout=open(diff_name, "w"))

    if ret == 0:
        print("test PASSED")
    else:
        print("test FAILED (did you remember to run this script and Firefox "
              "in the same directory?)")


if __name__ == "__main__":
    main()