Docs of WithDeadline refers to variable "d" which does not exist
in the docs.
This commit renames the time argument to "d" to make the doc work.
Change-Id: Ifd2c1be7d2e3f7dfb21cd9bb8ff7fc5039c8d3bd
Reviewed-on: https://go-review.googlesource.com/65130
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Previously, the suggested code would result in the following golint warning:
“should drop = 0 from declaration of var errorsOnlyKey; it is the zero value”
Change-Id: I1a302c1e40ca89acbc76897e39097ecd04865460
Reviewed-on: https://go-review.googlesource.com/60290
Reviewed-by: Ian Lance Taylor <iant@golang.org>
The Context definition to date has not defined what Err returns
before the Done channel is closed. Define that it returns nil,
as most implementations do.
All the standard context implementations (those in package
context and in golang.org/x/net/context) return Err() == nil
when Done is not yet closed. However, some non-standard
implementations may exist that return Err() != nil in this case,
as permitted by the Context definition before this date.
Call these "errorful implementations".
Because all the standard context implementations ensure that
Err() == nil when Done is not yet closed, clients now exist that
assume Err() != nil implies Done is closed and use calling Err
as a quick short-circuit check instead of first doing a non-blocking
receive from Done and then, if that succeeds, needing to call Err.
This assumption holds for all the standard Context implementations,
so these clients work fine in practice, even though they are making
unwarranted assumptions about the Context implementations.
Call these "technically incorrect clients".
If a technically incorrect client encounters an errorful
implementation, the client misbehaves. Because there are few
errorful implementations, over time we expect that many clients
will end up being technically incorrect without realizing it,
leading to latent, subtle bugs. If we want to eliminate these
latent, subtle bugs, there are two ways to do this:
either make errorful implementations more common
(exposing the client bugs more often) or redefine the Context
interface so that the clients are not buggy after all.
If we make errorful implementations more common, such
as by changing the standard context implementations to
return ErrNotDone instead of nil when Err is called before
Done is closed, this will shake out essentially all of the
technically incorrect clients, forcing people to find and fix
those clients during the transition to Go 1.9.
Technically this is allowed by the compatibility policy,
but we expect there are many pieces of code assuming
that Err() != nil means done, so updating will cause real pain.
If instead we disallow errorful implementations, then they
will need to be fixed as they are discovered, but the fault
will officially lie in the errorful Context implementation,
not in the clients. Technically this is disallowed by the compatibility
policy, because these errorful implementations were "correct"
in earlier versions of Go, except that they didn't work with
common client code. We expect there are hardly any errorful
implementations, so that disallowing them will be less disruptive
and more in the spirit of the compatibility policy.
This CL takes the path of expected least disruption,
narrowing the Context interface semantics and potentially
invalidating existing implementations. A survey of the
go-corpus v0.01 turned up only five Context implementations,
all trivial and none errorful (details in #19856).
We are aware of one early Context implementation inside Google,
from before even golang.org/x/net/context existed,
that is errorful. The misbehavior of an open-source library
when passed such a context is what prompted #19856.
That context implementation would be disallowed after this CL
and would need to be corrected. We are aware of no other
affected context implementations. On the other hand, a survey
of the go-corpus v0.01 turned up many instances of client
code assuming that Err() == nil implies not done yet
(details also in #19856). On balance, narrowing Context and
thereby allowing Err() == nil checks should invalidate significantly
less code than a push to flush out all the currently technically
incorrect Err() == nil checks.
If release feedback shows that we're wrong about this balance,
we can roll back this CL and try again in Go 1.10.
Fixes#19856.
Change-Id: Id45d126fac70e1fcc42d73e5a87ca1b66935b831
Reviewed-on: https://go-review.googlesource.com/40291
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Sameer Ajmani <sameer@golang.org>
It could have been defined the other way, but since the behavior has
been unspecified, this is the conservative approach for people writing
different implementations of the Context interface.
Change-Id: I7334a4c674bc2330cca6874f7cac1eb0eaea3cff
Reviewed-on: https://go-review.googlesource.com/37375
Reviewed-by: Matt Layher <mdlayher@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Sameer Ajmani <sameer@golang.org>
Run-TryBot: Sameer Ajmani <sameer@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
So that testing can use context in its public API.
For #16221.
Change-Id: I6263fa7266c336c9490f20164ce79336df44a57e
Reviewed-on: https://go-review.googlesource.com/32648
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
It already implemented the Timeout method,
but implementing the full net.Error is more convenient.
Fixes#14238 (again).
Change-Id: Ia87f897f0f35bcb49865e2355964049227951ca6
Reviewed-on: https://go-review.googlesource.com/30370
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Modifies context package to use map[]struct{} rather than map[]bool,
since the map is intended as a set object. Also adds Benchmarks to
the context package switching between different types of root nodes
and a tree with different depths.
Included below are bytes deltas between the old and new code, using
these benchmarks.
benchmark old bytes new bytes delta
BenchmarkContextCancelTree/depth=1/Root=Background-8 176 176 +0.00%
BenchmarkContextCancelTree/depth=1/Root=OpenCanceler-8 560 544 -2.86%
BenchmarkContextCancelTree/depth=1/Root=ClosedCanceler-8 352 352 +0.00%
BenchmarkContextCancelTree/depth=10/Root=Background-8 3632 3488 -3.96%
BenchmarkContextCancelTree/depth=10/Root=OpenCanceler-8 4016 3856 -3.98%
BenchmarkContextCancelTree/depth=10/Root=ClosedCanceler-8 1936 1936 +0.00%
BenchmarkContextCancelTree/depth=100/Root=Background-8 38192 36608 -4.15%
BenchmarkContextCancelTree/depth=100/Root=OpenCanceler-8 38576 36976 -4.15%
BenchmarkContextCancelTree/depth=100/Root=ClosedCanceler-8 17776 17776 +0.00%
BenchmarkContextCancelTree/depth=1000/Root=Background-8 383792 367808 -4.16%
BenchmarkContextCancelTree/depth=1000/Root=OpenCanceler-8 384176 368176 -4.16%
BenchmarkContextCancelTree/depth=1000/Root=ClosedCanceler-8 176176 176176 +0.00%
Change-Id: I699ad704d9f7b461214e1651d24941927315b525
Reviewed-on: https://go-review.googlesource.com/25270
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Adds a test case for calling context.WithDeadline() where the deadline
exists in the past. This change increases the code coverage of the
context package.
Change-Id: Ib486bf6157e779fafd9dab2b7364cdb5a06be36e
Reviewed-on: https://go-review.googlesource.com/25007
Reviewed-by: Sameer Ajmani <sameer@golang.org>
Run-TryBot: Sameer Ajmani <sameer@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Also replace double spaces after periods with single spaces.
Change-Id: Iedaea47595c5ce64e7e8aa3a368f36d49061c555
Reviewed-on: https://go-review.googlesource.com/24431
Reviewed-by: Alan Donovan <adonovan@google.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Some users don't realize that creating a Context with a CancelFunc
attaches a subtree to the parent, and that that subtree is not released
until the CancelFunc is called or the parent is canceled. Make this
clear early in the package docs, so that people learning about this
package have the right conceptual model.
Change-Id: I7c77a546c19c3751dd1f3a5bc827ad106dd1afbf
Reviewed-on: https://go-review.googlesource.com/24090
Reviewed-by: Alan Donovan <adonovan@google.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Change-Id: I41310ec88c889fda79d80eaf4a742a1000284f60
Reviewed-on: https://go-review.googlesource.com/23591
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Passes on OpenBSD now when running it with -count=500.
Presumably this will also fix the same problems seen on FreeBSD and
Windows.
Fixes#15158
Change-Id: I86451c901613dfa5ecff0c2ecc516527a3c011b3
Reviewed-on: https://go-review.googlesource.com/21840
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Andrew Gerrand <adg@golang.org>
Flaky tests are a distraction and cover up real problems.
File bugs instead and mark them as flaky.
This moves the net/http flaky test flagging mechanism to internal/testenv.
Updates #15156
Updates #15157
Updates #15158
Change-Id: I0e561cd2a09c0dec369cd4ed93bc5a2b40233dfe
Reviewed-on: https://go-review.googlesource.com/21614
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
This copies the golang.org/x/net/context package to the standard library.
It is imported from the x/net repo's git rev 1d9fd3b8333e (the most
recent modified to x/net/context as of 2016-03-07).
The corresponding change to x/net/context is in https://golang.org/cl/20347
Updates #14660
Change-Id: Ida14b1b7e115194d6218d9ac614548b9f41641cc
Reviewed-on: https://go-review.googlesource.com/20346
Reviewed-by: Sameer Ajmani <sameer@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
