Go 1.15 is not yet released. These are work-in-progress release notes. Go 1.15 is expected to be released in August 2020.
TODO
TODO
TODO
The GOPROXY environment variable now supports skipping proxies
that return errors. Proxy URLs may now be separated with either commas
(,) or pipe characters (|). If a proxy URL is
followed by a comma, the go command will only try the next proxy
in the list after a 404 or 410 HTTP response. If a proxy URL is followed by a
pipe character, the go command will try the next proxy in the
list after any error. Note that the default value of GOPROXY
remains https://proxy.golang.org,direct, which does not fall
back to direct in case of errors.
TODO
go test
Changing the -timeout flag now invalidates cached test results. A
cached result for a test run with a long timeout will no longer count as
passing when go test is re-invoked with a short one.
Various flag parsing issues in go test and
go vet have been fixed. Notably, flags specified
in GOFLAGS are handled more consistently, and
the -outputdir flag now interprets relative paths relative to the
working directory of the go command (rather than the working
directory of each individual test).
The location of the module cache may now be set with
the GOMODCACHE environment variable. The default value of
GOMODCACHE is GOPATH[0]/pkg/mod, the location of the
module cache before this change.
A workaround is now available for Windows "Access is denied" errors in
go commands that access the module cache, caused by external
programs concurrently scanning the file system (see
issue #36568). The workaround is
not enabled by default because it is not safe to use when Go versions lower
than 1.14.2 and 1.13.10 are running concurrently with the same module cache.
It can be enabled by explictly setting the environment variable
GODEBUG=modcacheunzipinplace=1.
TODO
Package unsafe's safety
rules allow converting an unsafe.Pointer
into uintptr when calling certain
functions. Previously, in some cases, the compiler allowed multiple
chained conversions (for example, syscall.Syscall(…,
uintptr(uintptr(ptr)), …)). The compiler now requires exactly
one conversion. Code that used multiple conversions should be
updated to satisfy the safety rules.
Go 1.15 includes a new package,
time/tzdata,
that permits embedding the timezone database into a program.
Importing this package (as import _ "time/tzdata")
permits the program to find timezone information even if the
timezone database is not available on the local system.
You can also embed the timezone database by building
with -tags timetzdata.
Either approach increases the size of the program by about 800 KB.
TODO
The testing.T type now has a Deadline method
that reports the time at which the test binary will have exceeded its
timeout.
A TestMain function is no longer required to call
os.Exit. If a TestMain function returns,
the test binary will call os.Exit with the value returned
by m.Run.
As always, there are various minor changes and updates to the library, made with the Go 1 promise of compatibility in mind.
TODO
The new
Dialer
type and its
DialContext
method permits using a context to both connect and handshake with a TLS server.
When the flag package sees -h or -help, and
those flags are not defined, the flag package prints a usage message.
If the FlagSet was created with
ExitOnError,
FlagSet.Parse would then
exit with a status of 2. In this release, the exit status for -h
or -help has been changed to 0. In particular, this applies to
the default handling of command line flags.
If an I/O operation exceeds a deadline set by
the Conn.SetDeadline,
Conn.SetReadDeadline,
or Conn.SetWriteDeadline methods, it will now
return an error that is or wraps
os.ErrDeadlineExceeded.
This may be used to reliably detect whether an error is due to
an exceeded deadline.
Earlier releases recommended calling the Timeout
method on the error, but I/O operations can return errors for
which Timeout returns true although a
deadline has not been exceeded.
All profile endpoints now support a "seconds" parameter. When present,
the endpoint profiles for the specified number of seconds and reports the difference.
The meaning of the "seconds" parameter in the cpu profile and
the trace endpoints is unchanged.
The new URL field
RawFragment and method EscapedFragment
provide detail about and control over the exact encoding of a particular fragment.
These are analogous to
RawPath and EscapedPath.
The new URL
method Redacted
returns the URL in string form with any password replaced with xxxxx.
If an I/O operation exceeds a deadline set by
the File.SetDeadline,
File.SetReadDeadline,
or File.SetWriteDeadline
methods, it will now return an error that is or wraps
os.ErrDeadlineExceeded.
This may be used to reliably detect whether an error is due to
an exceeded deadline.
Earlier releases recommended calling the Timeout
method on the error, but I/O operations can return errors for
which Timeout returns true although a
deadline has not been exceeded.
Package reflect now disallows accessing methods of all non-exported fields, whereas previously it allowed accessing those of non-exported, embedded fields. Code that relies on the previous behavior should be updated to instead access the corresponding promoted method of the enclosing variable.
If panic is invoked with a value whose type is derived from any
of: bool, complex64, complex128, float32, float64,
int, int8, int16, int32, int64, string,
uint, uint8, uint16, uint32, uint64, uintptr,
then the value will be printed, instead of just its address.
On a Unix system, if the kill command
or kill system call is used to send
a SIGSEGV, SIGBUS,
or SIGFPE signal to a Go program, and if the signal
is not being handled via
os/signal.Notify,
the Go program will now reliably crash with a stack trace.
In earlier releases the behavior was unpredictable.
The goroutine profile includes the profile labels associated with each goroutine
at the time of profiling. This feature is not yet implemented for the profile
reported with debug=2.
The new method
Map.LoadAndDelete
atomically deletes a key and returns the previous value if present.
The method
Map.Delete
is more efficient.
The new methods
T.TempDir and
B.TempDir and
return temporary directories that are automatically cleaned up
at the end of the test.
The new method
Ticker.Reset
supports changing the duration of a ticker.