diff -r 000000000000 -r 6474c204b198 memory/replace/dmd/check_test_output.py
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/memory/replace/dmd/check_test_output.py	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,128 @@
+#! /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], "<topsrcdir> <test.dmd>")
+        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 most stack frames.  The only thing
+    # we leave behind is a "DMD.cpp" entry if we see one or more frames that
+    # have DMD.cpp in them.  There is simply too much variation to do anything
+    # better than that.
+    #
+    # As for stack frame records, alas, we filter them out entirely because
+    # they have even more variation.
+
+    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".*(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 -- print a single line if we see one
+                # or more frames involving DMD.cpp.
+                seen_DMD_frame = False
+                for frame in fin:
+                    if re.match(r"   ", frame):
+                        m = test_frame_re.match(frame)
+                        if m:
+                            seen_DMD_frame = True
+                    else:
+                        # We're past the stack trace.
+                        if seen_DMD_frame:
+                            print("   ... DMD.cpp", file=fout)
+                        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()
+                line5 = fin.next()
+                line6 = fin.next()
+
+            else:
+                # A 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", expected_name, filtered_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()