Patchwork D7459: lock: pass "success" boolean to _afterlock callbacks

login
register
mail settings
Submitter phabricator
Date Nov. 20, 2019, 3:16 a.m.
Message ID <differential-rev-PHID-DREV-rgwqrhbghlfl63tlsnva-req@mercurial-scm.org>
Download mbox | patch
Permalink /patch/43371/
State Superseded
Headers show

Comments

phabricator - Nov. 20, 2019, 3:16 a.m.
spectral created this revision.
Herald added a subscriber: mercurial-devel.
Herald added a reviewer: hg-reviewers.

REVISION SUMMARY
  This lets the callback decide if it should actually run or not. I suspect that
  most callbacks (and hooks) *should not* run in this scenario, but I'm trying
  to not break any existing behavior. `persistmanifestcache`, however, seems
  actively dangerous to run: we just encountered an exception and the repo is in
  an unknown state (hopefully a consistent one due to transactions, but this is
  not 100% guaranteed), and the data we cache may be based on this unknown
  state.
  
  This was observed by our users since we wrap some of the functions that
  persistmanifestcache calls and it expects that the repo object is in a certain
  state that we'd set up earlier. If the user hits ctrl-c before we establish
  that state, we end up crashing there. I'm going to  make that extension
  resilient to this issue, but figured it might be a common issue and should be
  handled here as well instead of just working around the issue.

REPOSITORY
  rHG Mercurial

BRANCH
  default

REVISION DETAIL
  https://phab.mercurial-scm.org/D7459

AFFECTED FILES
  hgext/remotefilelog/__init__.py
  mercurial/bundle2.py
  mercurial/changegroup.py
  mercurial/localrepo.py
  mercurial/lock.py
  mercurial/manifest.py
  tests/test-lock.py

CHANGE DETAILS




To: spectral, #hg-reviewers
Cc: mercurial-devel

Patch

diff --git a/tests/test-lock.py b/tests/test-lock.py
--- a/tests/test-lock.py
+++ b/tests/test-lock.py
@@ -65,7 +65,7 @@ 
     def releasefn(self):
         self._releasecalled = True
 
-    def postreleasefn(self):
+    def postreleasefn(self, success):
         self._postreleasecalled = True
 
     def assertacquirecalled(self, called):
diff --git a/mercurial/manifest.py b/mercurial/manifest.py
--- a/mercurial/manifest.py
+++ b/mercurial/manifest.py
@@ -1572,7 +1572,11 @@ 
         reporef = weakref.ref(repo)
         manifestrevlogref = weakref.ref(self)
 
-        def persistmanifestcache():
+        def persistmanifestcache(success):
+            # Repo is in an unknown state, do not persist.
+            if not success:
+                return
+
             repo = reporef()
             self = manifestrevlogref()
             if repo is None or self is None:
diff --git a/mercurial/lock.py b/mercurial/lock.py
--- a/mercurial/lock.py
+++ b/mercurial/lock.py
@@ -233,7 +233,8 @@ 
         return self
 
     def __exit__(self, exc_type, exc_value, exc_tb):
-        self.release()
+        success = all(a is None for a in (exc_type, exc_value, exc_tb))
+        self.release(success=success)
 
     def __del__(self):
         if self.held:
@@ -408,7 +409,7 @@ 
                 self.acquirefn()
             self._inherited = False
 
-    def release(self):
+    def release(self, success=True):
         """release the lock and execute callback function if any
 
         If the lock has been acquired multiple times, the actual release is
@@ -433,7 +434,7 @@ 
             # at all.
             if not self._parentheld:
                 for callback in self.postrelease:
-                    callback()
+                    callback(success)
                 # Prevent double usage and help clear cycles.
                 self.postrelease = None
 
diff --git a/mercurial/localrepo.py b/mercurial/localrepo.py
--- a/mercurial/localrepo.py
+++ b/mercurial/localrepo.py
@@ -2180,7 +2180,7 @@ 
             # fixes the function accumulation.
             hookargs = tr2.hookargs
 
-            def hookfunc():
+            def hookfunc(unused_success):
                 repo = reporef()
                 if hook.hashook(repo.ui, b'txnclose-bookmark'):
                     bmchanges = sorted(tr.changes[b'bookmarks'].items())
@@ -2592,7 +2592,7 @@ 
                 l.postrelease.append(callback)
                 break
         else:  # no lock have been found.
-            callback()
+            callback(True)
 
     def lock(self, wait=True):
         '''Lock the repository store (.hg/store) and return a weak reference
@@ -2931,7 +2931,7 @@ 
                     )
                 raise
 
-        def commithook():
+        def commithook(unused_success):
             # hack for command that use a temporary commit (eg: histedit)
             # temporary commit got stripped before hook release
             if self.changelog.hasnode(ret):
@@ -3377,7 +3377,7 @@ 
         self.ui.debug(b'pushing key for "%s:%s"\n' % (namespace, key))
         ret = pushkey.push(self, namespace, key, old, new)
 
-        def runhook():
+        def runhook(unused_success):
             self.hook(
                 b'pushkey',
                 namespace=namespace,
diff --git a/mercurial/changegroup.py b/mercurial/changegroup.py
--- a/mercurial/changegroup.py
+++ b/mercurial/changegroup.py
@@ -436,7 +436,7 @@ 
 
             if changesets > 0:
 
-                def runhooks():
+                def runhooks(unused_success):
                     # These hooks run when the lock releases, not when the
                     # transaction closes. So it's possible for the changelog
                     # to have changed since we last saw it.
diff --git a/mercurial/bundle2.py b/mercurial/bundle2.py
--- a/mercurial/bundle2.py
+++ b/mercurial/bundle2.py
@@ -2372,7 +2372,7 @@ 
 
         if pushkeycompat:
 
-            def runhook():
+            def runhook(unused_success):
                 for hookargs in allhooks:
                     op.repo.hook(b'pushkey', **pycompat.strkwargs(hookargs))
 
diff --git a/hgext/remotefilelog/__init__.py b/hgext/remotefilelog/__init__.py
--- a/hgext/remotefilelog/__init__.py
+++ b/hgext/remotefilelog/__init__.py
@@ -1063,7 +1063,7 @@ 
     # update a revset with a date limit
     bgprefetchrevs = revdatelimit(ui, bgprefetchrevs)
 
-    def anon():
+    def anon(unused_success):
         if util.safehasattr(repo, b'ranprefetch') and repo.ranprefetch:
             return
         repo.ranprefetch = True