Add trace comparison scripts #327

This adds some tools and documentation (!`README.md) for comparing
vm traces between geth and pyethapp/pyethereum.

debugging/README.md

@@ -15,6 +15,12 @@ Create traces from tester file:
 
 - with pyethapp
 
-    pyethapp --log-json -d /tmp/bt -l:trace blocktest \
-    tests/BlockchainTests/bcRPC_API_Test.json RPC_API_Test 2>&1 | grep "eth.vm.op"|while IFS=$'\n' read -r line; \
-    do python -mjson.tool <<<"$line"; done
+    pyethapp --log-json -d /tmp/bt -l:trace blocktest tests/BlockchainTests/bcRPC_API_Test.json RPC_API_Test 2>&1 | grep "eth.vm.op" > pylog.jsons
+
+Now we can diff traces between geth and pyethapp. In the `debugging` folder run:
+
+    ./compare_logs.py <block_number>
+
+    # e.g.
+
+    ./compare_logs.py 3  # to compare the traces of block 3

debugging/compare_logs.py

@@ -0,0 +1,21 @@
+#!/usr/bin/env python
+import sys
+import json
+from deepdiff import DeepDiff
+from pprint import pprint
+from print_pylog import read_pythons
+# from __future__ import print_function
+
+
+def read_geth(fn):
+    with open(fn) as f:
+        slogs = json.load(f)['result']['structLogs']
+    return slogs
+
+
+if __name__ == '__main__':
+    pyblocks = read_pythons()
+    blocknum = int(sys.argv[1]) if len(sys.argv) > 1 else 1
+
+    goblock = read_geth("trace-{}.json".format(blocknum))
+    pprint(DeepDiff(goblock, pyblocks[blocknum]))

debugging/print_pylog.py

@@ -0,0 +1,25 @@
+#!/usr/bin/env python
+import sys
+import json
+from collections import defaultdict
+
+
+def read_pythons(fn='pylog.jsons'):
+    with open(fn) as f:
+        lines = [json.loads(line) for line in f.readlines()]
+    blocks = defaultdict(list)
+    bnum = 0
+    for l in lines:
+        if l['pc'] == 0:
+            bnum += 1
+        # remove py slogging specifics:
+        l.pop('event')
+        l.pop('level')
+        blocks[bnum].append(l)
+    return blocks
+
+if __name__ == '__main__':
+    pyblocks = read_pythons()
+    blocknum = int(sys.argv[1]) if len(sys.argv) > 1 else 1
+
+    print json.dumps(pyblocks[blocknum], indent=2)