Now that all known format variants exists outside of the function, we can gather
them in a lists. This build a single entry point other code can use (current
target: extensions).
The repository upgrade code is updated to simply use entries from this list.
As a side effect this will also allow extensions to register their own format
variants, to do this "properly" we should introduce a "registrar" for this
category of object. However I prefer to keep this series simple, and that will
be adventure for future time.
Our goal here is to get top level definition for all the format variants. Having
them defined outside of the function enabled other users of that logic.
They are two keys components of a format variant:
1) the name and various descriptions of its effect,
2) the code that checks if the repo is using this variant and if the config
enables it.
That second items make us pick a class-based approach, since different variants
requires different code (even if in practice, many can reuse the same logic).
Each variants define its own class that is then used like a singleton. The
class-based approach also clarify the definitions part a bit since each are
simple assignment in an indented block.
The 'fromdefault' and 'fromconfig' are respectively replaced by a class
attribute and a method to be called at the one place where "fromconfig"
matters.
Overall, they are many viable approach for this, but this is the one I picked.
The 'deficiency' type has multiple specificities. We create a dedicated class to
host them. More logic will be added incrementally in future changesets.
I've not found anything related to color + windows on the bug tracker. So I'm
suggesting we get bolder and turn it on for windows too in the release
candidate. We can always backout this changeset if we find serious issue on
windows.
Color support is all in core for a couple of months. I've browsed the bug tracker
without finding any blocker bug. So I'm moving forward and enable color on by
default before '4.2-rc'. In the worse case, having it on in the release
candidate will help us to find blocker bug and we can turn it off for the final
release.
I remember people talking about issue with Windows during the freeze so I'm
keeping it off by default on that OS.
We could do various cleaning of the color used and the label issued. However
the label are probably already in our backward compatibility envelope since the
color extensions has been around since for ever and I do not think the color
choice themself should be considered BC. So I think we should rather gives color
to all user sooner than later.
A couple of test needs to be updated to avoid having color related control code
spoil the tested output.
Many have seen a "stream ended unexpectedly" error. This message is
raised from changegroup.readexactly() when a read(n) operation fails
to return exactly N bytes.
I believe most occurrences of this error in the wild stem from
the code changed in this patch. Before, if bundle2's part applicator
raised an Exception when processing/applying parts, the exception
handler would attempt to iterate the remaining parts. If I/O
during this iteration failed, it would likely raise the
"stream ended unexpectedly" exception.
The problem with this approach is that if we already encountered
an I/O error iterating the bundle2 data during application, then
any further I/O would almost certainly fail. If the original stream
were closed, changegroup.readexactly() would obtain an empty
string, triggering "stream ended unexpectedly" with "got 0." This is
the error message that users would see. What's worse is that the
original I/O related exception would be lost since a new exception
would be raised. This made debugging the actual I/O failure
effectively impossible.
This patch changes the exception handler for bundle2 application to
ignore errors when seeking the underlying stream. When the underlying
error is I/O related, the seek should fail fast and the original
exception will be re-raised. The output changes in
test-http-bad-server.t demonstrate this.
When the underlying error is not I/O related and the stream can be
seeked, the old behavior is preserved.
As part of writing test-http-bad-server.t, I noticed that some
requests include an empty Vary HTTP request header.
The Vary HTTP request header indicates which headers should be taken
into account when determining if a cached response can be used. It also
accepts the special value of "*".
The previous code unconditionally added a Vary header. This could lead
to an empty header value. While I don't believe this violates the HTTP
spec, this is weird and just wastes bytes. So this patch changes
behavior to only send a Vary header when it has a value.
Some low-level wire protocol byte reporting tests changed. In some
cases, the exact point of data termination changed. However, the
behavior being tested - that clients react when the connection is
closed in the middle of an HTTP request line or header - remains
unchanged.
The previous logic had many shortcoming (eg: looking at the head only, not
handling prune, etc...), the new logic use a more robust approach:
For each head, we check if after the push all changesets exclusive to this heads
will be obsolete. If they are, the branch considered be "replaced".
To check if a changeset will be obsolete, we simply checks:
* the changeset phase
* the existence of a marker relevant to the "pushed set" that affects the
changesets..
This fixes two major issues of the previous algorithm:
* branch partially rewritten (eg: head but not root) are no longer detected as
replaced,
* Prune are now properly handled.
(This implementation was introduction in the evolve extension, version 6.0.0.)
This new algorithm has an extended number of tests, a basic one is provided
in this patch. The others will be introduced in their own changeset for clarity.
In addition, we stop trying to process heads unknown locally, we do not have
enough data to take an informed decision so we should stop pretending we do.
This reflect a test that is now update.
I've been using `hg serve --web-conf ...` with a simple '/=projects/**' [paths]
configuration for awhile without issue. Let's ditch the need for the manual
configuration in this case, and limit the repos served to the actual subrepos.
This doesn't attempt to handle the case where a new subrepo appears while the
server is running. That could probably be handled with a hook if somebody wants
it. But it's such a rare case, it probably doesn't matter for the temporary
serves.
The main repo is served at '/', just like a repository without subrepos. I'm
not sure why the duplicate 'adding ...' lines appear on Linux. They don't
appear on Windows (see 3f4ff1bdf101), so they are optional.
Subrepositories that are configured with '../path' or absolute paths are not
cloneable from the server. (They aren't cloneable locally either, unless they
also exist at their configured source, perhaps via the share extension.) They
are still served, so that they can be browsed, or cloned individually. If we
care about that cloning someday, we can probably just add the extra entries to
the webconf dictionary. Even if the entries use '../' to escape the root, only
the related subrepositories would end up in the dictionary.
Now that the response instance itself is wrapped with error
handling, we no longer need this code. This code became dead
with the previous patch because the added code catches
HTTPException and re-raises as something else.
There were a handful of places in the code where HTTPResponse.read()
was called with no explicit error handling or with inconsistent
error handling. In order to eliminate this class of bug, we globally
swap out HTTPResponse.read() with a unified error handler.
I initially attempted to fix all call sites. However, after
going down that rabbit hole, I figured it was best to just change
read() to do what we want. This appears to be a worthwhile
change, as the tests demonstrate many of our uncaught exceptions
go away.
To better represent this class of failure, we introduce a new
error type. The main benefit over IOError is it can hold a hint.
I'm receptive to tweaking its name or inheritance.
An upcoming patch will add low-level testing of the bytes being sent
over the wire. As part of developing that test, I discovered that the
order of headers in HTTP requests wasn't deterministic. This patch
makes the order deterministic to make things easier to test.
We parse "descend" symbol as a Boolean using getboolean (prior extraction by
getargsdict already checked that it is a symbol).
In tests, check for error cases and vary Boolean values here and there.
The tag changes information we compute is now written to disk. This gives
hooks full access to that data.
The format picked for that file uses a 2 characters prefix for the action:
-R: tag removed
+A: tag added
-M: tag moved (old value)
+M: tag moved (new value)
This format allows hooks to easily select the line that matters to them without
having to post process the file too much. Here is a couple of examples:
* to select all newly tagged changeset, match "^+",
* to detect tag move, match "^.M",
* to detect tag deletion, match "-R".
Once again we rely on the fact the tag tests run through all possible
situations to test this change.
We now compute the proper actuall differences between tags before and after the
transaction. This catch a couple of false positives in the tests.
The compute the full difference since we are about to make this data available
to hooks in the next changeset.
This changeset introduces detection of tags changes during transaction. When
this happens a 'tag_moved=1' argument is set for hooks, similar to what we do
for bookmarks and phases.
This code is disabled by default as there are still various performance
concerns. Some require a smarter use of our existing tag caches and some other
require rework around the transaction logic to skip execution when unneeded.
These performance improvements have been delayed, I would like to be able to
experiment and stabilize the feature behavior first.
Later changesets will push the concept further and provide a way for hooks to
know what are the actual changes introduced by the transaction. Similar work
is needed for the other families of changes (bookmark, phase, obsolescence,
etc). Upgrade of the transaction logic will likely be performed at the same
time.
The current code can report some false positive when .hgtags file changes but
resulting tags are unchanged. This will be fixed in the next changeset.
For testing, we simply globally enable a hook in the tag test as all the
possible tag update cases should exist there. A couple of them show the false
positive mentioned above.
See in code documentation for more details.
This will get used to compare tags between two set of revisions during a
transaction (pre and post heads). The end goal is to be able to track tags
movement in transaction hooks.
If initial 'fctx' has changes in line range with respect to its parents, we
yield it first. This makes 'followlines(..., descend=True)' consistent with
'descendants()' revset which yields the starting revision.
We reuse one iteration of blockancestors() which does exactly what we want.
In test-annotate.t, adjust 'startrev' in one case to cover the situation where
the starting revision does not touch specified line range.
If this assertion fails, this indicates a flaw in the algorithm. So fail fast
instead of possibly producing wrong results.
Also extend the target line range in test to catch a merge changeset with all
its parents.
Module 'appdirs' tries to import win32com.shell (and catch ImportError as an
indication of failure) to check whether some further functionality should
be implemented one or another way [1]. Of course, demandimport lets it down, so
if we want appdirs to work we have to add it to demandimport's ignore list.
The reason we want appdirs to work is becuase it is used by setuptools [2] to
determine egg cache location. Only fairly recent versions of setuptools depend
on this so people don't see this often.
[1] https://github.com/ActiveState/appdirs/blob/master/appdirs.py#L560
[2] aae0a92811/pkg_resources/__init__.py (L1369)
The prior code used to ignore all errors, which was intended to
deal with a decade-old problem with writing to broken pipes on
Windows.
However, that code inadvertantly went a lot further, making it
impossible to detect *all* I/O errors on stdio ... but only sometimes.
What actually happened was that if Mercurial wrote less than a stdio
buffer's worth of output (the overwhelmingly common case for most
commands), any error that occurred would get swallowed here. But
if the buffering strategy changed, an unhandled IOError could be
raised from any number of other locations.
Because we now have a top-level StdioError handler, and ui._write
and ui._write_err (and now flush!) will raise that exception, we
have one rational place to detect and handle these errors.
We attempt to report what went wrong, and more importantly exit the
program with an error code.
(The exception we catch is not yet raised anywhere in the code.)
Mercurial currently fails to notice failures to write to stdout or
stderr. A correctly functioning command line tool should detect
this and exit with an error code.
To achieve this, we need a little extra plumbing, which we start
adding here.
In spite of its longstanding use, Python's built-in atexit code is
not suitable for Mercurial's purposes, for several reasons:
* Handlers run after application code has finished.
* Because of this, the code that runs handlers swallows exceptions
(since there's no possible stacktrace to associate errors with).
If we're lucky, we'll get something spat out to stderr (if stderr
still works), which of course isn't any use in a big deployment
where it's important that exceptions get logged and aggregated.
* Mercurial's current atexit handlers make unfortunate assumptions
about process state (specifically stdio) that, coupled with the
above problems, make it impossible to deal with certain categories
of error (try "hg status > /dev/full" on a Linux box).
* In Python 3, the atexit implementation is completely hidden, so
we can't hijack the platform's atexit code to run handlers at a
time of our choosing.
As a result, here's a perfectly cromulent atexit-like implementation
over which we have control. This lets us decide exactly when the
handlers run (after each request has completed), and control what
the process state is when that occurs (and afterwards).
In the initial implementation of blockdescendants (and thus followlines(...,
descend=True) revset), only the first branch encountered in descending
direction was followed.
Update the algorithm so that all children of a revision ('x' in code) are
considered. Accordingly, we need to prevent a child revision to be yielded
multiple times when it gets visited through different path, so we skip 'i'
when this occurs. Finally, since we now consider all parents of a possible
child touching a given line range, we take care of yielding the child if it
has a diff in specified line range with at least one of its parent (same logic
as blockancestors()).
Our current deprecation warning mechanism relies on ui object. They are case
where we cannot have access to the UI object. On a general basis we avoid using
the python mechanism for deprecation warning because up to Python 2.6 it is
exposing warning to unsuspecting user who cannot do anything to deal with them.
So we build a "safe" strategy to hide this warnings behind a flag in an
environment variable. The test runner set this flag so that tests show these
warning. This will help us marker API as deprecated for extensions to update
their code.
Mostly copy CSS rules from style-paper.css into style-gitweb.css. The only
modification is addition of !important on "background-color" rule for
"pre.sourcelines > span.followlines-selected" selector as the background color
is otherwise overriden by "pre.sourcelines.stripes > :nth-child(4n+4)" rule.
As for paper style, in d9b8811bed4a, we display "diff" data as an additional
row in the table of revision entries for the gitweb template.
Also, as these additional diff rows have a white background, they may be
confused with log entry rows ("age", "author", "description", "links") of even
parity (parity0 also have a white background). So we disable parity colors for
log entry rows when diff is displayed and fix the color to the
"dark" parity (i.e. parity1 #f6f6f0) so that it's always distinguishable from
As for paper style, in a58e79a03a6e, we display a "(following lines
<fromline>:<toline> <a href='...'>back to filelog</a>)" message alongside the
file name when "linerange" query parameter is present.
This is the beginning of a wip/smartlog view. It is basically a manually
constructed (read: fast) revset function to collect "relevant"
changesets combined with a custom template and a graph displayer.
It obviously needs a lot of work.
I'd like to get *something* usable in 4.2 so `hg show` has some value
to end-users.
Let the bikeshedding begin.
We change the content of the followlines popup to display two links inviting
to follow the history of selected lines in ascending (as before) and
descending directions. The popup now renders as:
follow history of lines <fromline>:<toline>:
<a href=...>ascending</a> / <a href=...>descending</a>
When this "descend" query parameter is present along with "linerange"
parameter, we get revisions following line range in descending order. The
parameter has no effect without "linerange".
This is useful to follow changes in a block of lines forward in the history
(for instance, when one wants to find out how a function evolved from a point
in history).
We added a 'descend' parameter to followlines(), which defaults to False. If
True, followlines() returns descendants of startrev.
Because context.blockdescendants() does not follow renames, these are not
followed by the revset either, so history will end when a rename occurs (as
can be seen in tests).
This is symmetrical with blockancestors() and yields descendants of a filectx
with changes in the given line range. The noticeable difference is that the
algorithm does not follow renames (probably because filelog.descendants() does
not), so we are missing branches with renames.
