.

wcfs/wcfs_test.py

@@ -55,8 +55,8 @@ testdb = None
 testzurl = None     # URL of testdb
 testmntpt = None    # wcfs is mounted here
 def setup_module():
-    # if wcfs.py receives SIGBUS because wcfs.go panics, we want to see
-    # python-level traceback instead of being killed.
+    # if wcfs.py receives SIGBUS because wcfs.go panics while serving mmap'ed
+    # read, we want to see python-level traceback instead of being killed.
     install_sigbus_trap()
 
     global testdb, testzurl, testmntpt
@@ -214,7 +214,7 @@ class tDB:
         #   check the thread is the same when .root is used )
         t._maintid = gettid()
 
-        # prepare initail objects for test: zfile, nonzfile
+        # prepare initial objects for test: zfile, nonzfile
         t.root['!file'] = t.nonzfile  = Persistent()
         t.root['zfile'] = t.zfile     = ZBigFile(blksize)
         t.at0 = t.commit()
@@ -248,7 +248,7 @@ class tDB:
     def openwatch(t):   # -> tWatchLink
         return tWatchLink(t)
 
-    # change schedules zf to be changed according changeDelta at commit.
+    # change schedules zf to be changed according to changeDelta at commit.
     #
     # changeDelta: {} blk -> data.
     # data can be both bytes and unicode.
@@ -267,17 +267,15 @@ class tDB:
     #
     # zf and changeDelta can be optionally provided, in which case .change(zf,
     # changeDelta) call is made before actually committing.
-    def commit(t, zf=None, changeDelta=None):
+    def commit(t, zf=None, changeDelta=None):   # -> tAt
         if zf is not None:
             assert changeDelta is not None
             t.change(zf, changeDelta)
 
-        # we'll verify that all changed objects come from the same ZODB connection
-        zconns = set()
-
         # perform modifications scheduled by change.
         # use !wcfs mode so that we prepare data independently of wcfs code paths.
         dF = DF()
+        zconns = set()
         for zf, zfDelta in t._changed.items():
             dfile = DFile()
             zconns.add(zf._p_jar)
@@ -289,6 +287,7 @@ class tDB:
                 memcpy(vma, data)
             dF.byfile[zf] = dfile
 
+        # verify that all changed objects come from the same ZODB connection
         assert len(zconns) in (0, 1)    # either nothing to commit or all from the same zconn
         if len(zconns) == 1:
             zconn = zconns.pop()
@@ -504,7 +503,6 @@ class tFile:
     # provided pinokByWLink when it is present.
     @func
     def assertBlk(t, blk, dataok, pinokByWLink=None):
-        #print('assertBlk #%d' % blk)
         # XXX -> assertCtx('blk #%d' % blk)
         def _():
             assertCtx = 'blk #%d' % blk
@@ -555,7 +553,6 @@ class tFile:
                         assert cached == 0
                         # even if @head[blk] is uncached, the block could be
                         # already pinned by setup watch
-                        # XXX assert blkaccessed.rev > w.at => w.pinned
                         if blk not in w.pinned:
                             pinok = {blk: t.tdb._blkRevAt(t.zf, blk, w.at)}
                             shouldPin = True
@@ -569,7 +566,7 @@ class tFile:
         for wlink, pinok in pinokByWLink.items():
             pinokByWLink[wlink] = (t.zf, pinok)
 
-        # access 1 bye on the block and verify that wcfs sends us correct pins
+        # access 1 byte on the block and verify that wcfs sends us correct pins
         blkview = t._blk(blk)
         assert t.cached()[blk] == cached
 
@@ -625,9 +622,9 @@ class tFile:
     #
     # Expected blocks may be given with size < zf.blksize. In such case they
     # are implicitly appended with trailing zeros. If a block is specified as
-    # 'x' - this particular block is not checked.
+    # 'x' - this particular block is not accessed and is not checked.
     #
-    # It also checks file size and optionally mtime.
+    # The file size and optionally mtime are also verified.
     def assertData(t, dataokv, mtime=None):
         st = os.fstat(t.f.fileno())
         assert st.st_size == len(dataokv)*t.blksize
@@ -823,7 +820,7 @@ class tWatchLink:
         return _rx
 
     def _sendReq(t, ctx, req):  # -> rxq
-        stream = 1
+        stream = 1  # XXX -> dynamic
 
         rxq = chan()
         with t._rxmu:
@@ -1032,7 +1029,7 @@ def _watch(twlink, zf, at, pinok, replyok):
 #
 # f(ctx, eventv)
 # pinokByWLink: {} tWatchLink -> (zf, {} blk -> at).
-# pinfunc(wlink, foid, blk, at) | None.     XXX foid -> ZBigFile?
+# pinfunc(wlink, foid, blk, at) | None.
 #
 # pinfunc is called after pin request is received from wcfs, but before pin ack
 # is replied back. Pinfunc must not block.
@@ -1135,8 +1132,6 @@ def _blkDataAt(t, zf, blk, at): # -> (data, rev)
     if at is None:
         at = t.head
 
-    # XXX dup wrt _pinnedAt
-
     # all changes to zf
     vdf = [_.byfile[zf] for _ in t.dFtail if zf in _.byfile]
 
@@ -1150,8 +1145,8 @@ def _blkDataAt(t, zf, blk, at): # -> (data, rev)
         _ = blkhistoryat[-1]
         data = _.ddata[blk]
         rev  = _.rev
-        assert rev <= at
 
+    assert rev <= at
     return data, rev
 
 # _blkRevAt returns expected zf[blk] revision as of @at database state.
@@ -1171,8 +1166,6 @@ def _blkRevAt(t, zf, blk, at): # -> rev
 #                                                       ; (and so is tracked by wcfs)
 @func(tDB)
 def _pinnedAt(t, zf, at):  # -> pin = {} blk -> rev
-    # XXX dup in _blkDataAt
-
     # all changes to zf
     vdf = [_.byfile[zf] for _ in t.dFtail if zf in _.byfile]
 
@@ -1182,15 +1175,8 @@ def _pinnedAt(t, zf, at):  # -> pin = {} blk -> rev
         for blk in df.ddata:
             if blk in pin:
                 continue
-            # history of blk changes <= at
-            blkhistoryat = [_.rev for _ in vdf if blk in _.ddata and _.rev <= at]
-            if len(blkhistoryat) == 0:
-                pinrev = t.dFtail[0].rev    # was hole - at0  XXX -> pin to z64?
-            else:
-                pinrev = blkhistoryat[-1]
-            assert pinrev <= at
             if blk in t._blkaccessed(zf):
-                pin[blk] = pinrev
+                pin[blk] = t._blkRevAt(zf, blk, at)
 
     return pin
 
@@ -1817,7 +1803,7 @@ def tidtime(tid):
     # NOTE pytest.approx supports only ==, not e.g. <, so we use plain round.
     return round(t, 6)
 
-# tidfromtime converts time into corresponding transacton ID.
+# tidfromtime converts time into corresponding transaction ID.
 def tidfromtime(t):
     f = t - int(t)      # fraction of seconds
     t = int(t)
@@ -1955,7 +1941,7 @@ defer = xdefer
 del xdefer
 
 
-# ready reports whether chan ch is ready
+# ready reports whether chan ch is ready.
 def ready(ch):
     _, _rx = select(
         default,    # 0