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Fixes #59627
Change-Id: Icd6a9803e213596de6136ec980b0a352c450e6f7
Reviewed-on: https://go-review.googlesource.com/c/go/+/496142
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
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Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
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Use the explicit API for acquiring an empty available buffer,
rather than the hack that's implemented in terms of Bytes and Len.
Change-Id: If286ed42693acd61ffe28dc849ed4b76c3ae4434
Reviewed-on: https://go-review.googlesource.com/c/go/+/476337
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Auto-Submit: Joseph Tsai <joetsai@digital-static.net>
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The folded name logic (despite all attempts to optimize it)
was fundamentally an O(n) operation where every field in a struct
needed to be linearly scanned in order to find a match.
This made unmashaling of unknown fields always O(n).
Instead of optimizing the comparison for each field,
make it such that we can look up a name in O(1).
We accomplish this by maintaining a map keyed by pre-folded names,
which we can pre-calculate when processing the struct type.
Using a stack-allocated buffer, we can fold the input name and
look up its presence in the map.
Also, instead of mapping from names to indexes,
map directly to a pointer to the field information.
The memory cost of this is the same and avoids an extra slice index.
The new logic is both simpler and faster.
Performance:
name old time/op new time/op delta
CodeDecoder 2.47ms ± 4% 2.42ms ± 2% -1.83% (p=0.022 n=10+9)
UnicodeDecoder 259ns ± 2% 248ns ± 1% -4.32% (p=0.000 n=10+10)
DecoderStream 150ns ± 1% 149ns ± 1% ~ (p=0.516 n=10+10)
CodeUnmarshal 3.13ms ± 2% 3.09ms ± 2% -1.37% (p=0.022 n=10+9)
CodeUnmarshalReuse 2.50ms ± 1% 2.45ms ± 1% -1.96% (p=0.001 n=8+9)
UnmarshalString 67.1ns ± 5% 64.5ns ± 5% -3.90% (p=0.005 n=10+10)
UnmarshalFloat64 60.1ns ± 4% 58.4ns ± 2% -2.89% (p=0.002 n=10+8)
UnmarshalInt64 51.0ns ± 4% 49.2ns ± 1% -3.53% (p=0.001 n=10+8)
Issue10335 80.7ns ± 2% 79.2ns ± 1% -1.82% (p=0.016 n=10+8)
Issue34127 28.6ns ± 3% 28.8ns ± 3% ~ (p=0.388 n=9+10)
Unmapped 177ns ± 2% 177ns ± 2% ~ (p=0.956 n=10+10)
Change-Id: I478b2b958f5a63a69c9a991a39cd5ffb43244a2a
Reviewed-on: https://go-review.googlesource.com/c/go/+/471196
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Run-TryBot: Joseph Tsai <joetsai@digital-static.net>
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Reviewed-by: Johan Brandhorst-Satzkorn <johan.brandhorst@gmail.com>
Reviewed-by: Than McIntosh <thanm@google.com>
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
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Use append for HTMLEscape similar to Indent and Compact.
Move it to indent.go alongside Compact, as it shares similar logic.
In a future CL, we will modify appendCompact to be written in terms
of appendHTMLEscape, but we need to first move the JSON decoder logic
out of the main loop of appendCompact.
Change-Id: I131c64cd53d5d2b4ca798b37349aeefe17b418c7
Reviewed-on: https://go-review.googlesource.com/c/go/+/471198
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Auto-Submit: Joseph Tsai <joetsai@digital-static.net>
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v.SetZero() is faster than v.Set(reflect.Zero(v.Type()))
and was recently added in Go 1.20.
Benchmark numbers are largely unchanged since this mainly
affects the unmarshaling of large numbers of JSON nulls,
which our benchmarks do not heavily exercise.
Change-Id: I464f60f63c9027e63a99fd5da92e7ab782018329
Reviewed-on: https://go-review.googlesource.com/c/go/+/471195
Reviewed-by: Johan Brandhorst-Satzkorn <johan.brandhorst@gmail.com>
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With native support for fuzzing in the Go toolchain,
rely instead on the fuzz tests declared in fuzz_test.go.
Change-Id: I601842cd0bc7e64ea3bfdafbbbc3534df11acf59
Reviewed-on: https://go-review.googlesource.com/c/go/+/471197
Reviewed-by: Johan Brandhorst-Satzkorn <johan.brandhorst@gmail.com>
Reviewed-by: Than McIntosh <thanm@google.com>
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The Grow method is generally a more efficient way to grow a slice.
The older approach of using reflect.MakeSlice has to
waste effort zeroing the elements overwritten by the older slice
and has to allocate the slice header on the heap.
Performance:
name old time/op new time/op delta
CodeDecoder 2.41ms ± 2% 2.42ms ± 2% ~
CodeUnmarshal 3.12ms ± 3% 3.13ms ± 3% ~
CodeUnmarshalReuse 2.49ms ± 3% 2.52ms ± 3% ~
name old alloc/op new alloc/op delta
CodeDecoder 2.00MB ± 1% 1.99MB ± 1% ~
CodeUnmarshal 3.05MB ± 0% 2.92MB ± 0% -4.23%
CodeUnmarshalReuse 1.68MB ± 0% 1.68MB ± 0% -0.32%
name old allocs/op new allocs/op delta
CodeDecoder 77.1k ± 0% 77.0k ± 0% -0.09%
CodeUnmarshal 92.7k ± 0% 91.3k ± 0% -1.47%
CodeUnmarshalReuse 77.1k ± 0% 77.0k ± 0% -0.07%
The Code benchmarks (which are the only ones that uses slices)
are largely unaffected. There is a slight reduction in allocations.
A histogram of slice lengths from the Code testdata is as follows:
≤1: 392
≤2: 256
≤4: 252
≤8: 152
≤16: 126
≤32: 78
≤64: 62
≤128: 46
≤256: 18
≤512: 10
≤1024: 8
A bulk majority of slice lengths are 8 elements or under.
Use of reflect.Value.Grow performs better for larger slices since
it can avoid the zeroing of memory and has a faster growth rate.
However, Grow grows starting from 1 element,
with a 2x growth rate until some threshold (currently 512),
Starting from 1 ensures better utilization of the heap,
but at the cost of more frequent regrowth early on.
In comparison, the previous logic always started
with a minimum of 4 elements, which leads to a wasted capacity
of 75% for the highly frequent case of a single element slice.
The older code always had a growth rate of 1.5x,
and so wastes less memory for number of elements below 512.
All in all, there are too many factors that hurt or help performance.
Rergardless, the simplicity of favoring reflect.Value.Grow
over manually managing growth rates is a welcome simplification.
Change-Id: I62868a7f112ece3c2da3b4f6bdf74d397110243c
Reviewed-on: https://go-review.googlesource.com/c/go/+/471175
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As part of the effort to rely less on bytes.Buffer,
switch most operations to use more natural append-like operations.
This makes it easier to swap bytes.Buffer out with a buffer type
that only needs to support a minimal subset of operations.
As a simplification, we can remove the use of the scratch buffer
and use the available capacity of the buffer itself as the scratch.
Also, declare an inlineable mayAppendQuote function to conditionally
append a double-quote if necessary.
Performance:
name old time/op new time/op delta
CodeEncoder 405µs ± 2% 397µs ± 2% -1.94% (p=0.000 n=20+20)
CodeEncoderError 453µs ± 1% 444µs ± 4% -1.83% (p=0.000 n=19+19)
CodeMarshal 559µs ± 4% 548µs ± 2% -2.02% (p=0.001 n=19+17)
CodeMarshalError 724µs ± 3% 716µs ± 2% -1.13% (p=0.030 n=19+20)
EncodeMarshaler 24.9ns ±15% 22.9ns ± 5% ~ (p=0.086 n=20+17)
EncoderEncode 14.0ns ±27% 15.0ns ±20% ~ (p=0.365 n=20+20)
There is a slight performance gain across the board due to
the elimination of the scratch buffer. Appends are done directly
into the unused capacity of the underlying buffer,
avoiding an additional copy. See #53685
Updates #27735
Change-Id: Icf6d612a7f7a51ecd10097af092762dd1225d49e
Reviewed-on: https://go-review.googlesource.com/c/go/+/469558
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This is part of the effort to reduce direct reliance on bytes.Buffer
so that we can use a buffer with better pooling characteristics.
Unify these two methods as a single version that uses generics
to reduce duplicated logic. Unfortunately, we lack a generic
version of utf8.DecodeRune (see #56948), so we cast []byte to string.
The []byte variant is slightly slower for multi-byte unicode since
casting results in a stack-allocated copy operation.
Fortunately, this code path is used only for TextMarshalers.
We can also delete TestStringBytes, which exists to ensure
that the two duplicate implementations remain in sync.
Performance:
name old time/op new time/op delta
CodeEncoder 399µs ± 2% 409µs ± 2% +2.59% (p=0.000 n=9+9)
CodeEncoderError 450µs ± 1% 451µs ± 2% ~ (p=0.684 n=10+10)
CodeMarshal 553µs ± 2% 562µs ± 3% ~ (p=0.075 n=10+10)
CodeMarshalError 733µs ± 3% 737µs ± 2% ~ (p=0.400 n=9+10)
EncodeMarshaler 24.9ns ±12% 24.1ns ±13% ~ (p=0.190 n=10+10)
EncoderEncode 12.3ns ± 3% 14.7ns ±20% ~ (p=0.315 n=8+10)
name old speed new speed delta
CodeEncoder 4.87GB/s ± 2% 4.74GB/s ± 2% -2.53% (p=0.000 n=9+9)
CodeEncoderError 4.31GB/s ± 1% 4.30GB/s ± 2% ~ (p=0.684 n=10+10)
CodeMarshal 3.51GB/s ± 2% 3.46GB/s ± 3% ~ (p=0.075 n=10+10)
CodeMarshalError 2.65GB/s ± 3% 2.63GB/s ± 2% ~ (p=0.400 n=9+10)
name old alloc/op new alloc/op delta
CodeEncoder 327B ±347% 447B ±232% +36.93% (p=0.034 n=9+10)
CodeEncoderError 142B ± 1% 143B ± 0% ~ (p=1.000 n=8+7)
CodeMarshal 1.96MB ± 2% 1.96MB ± 2% ~ (p=0.468 n=10+10)
CodeMarshalError 2.04MB ± 3% 2.03MB ± 1% ~ (p=0.971 n=10+10)
EncodeMarshaler 4.00B ± 0% 4.00B ± 0% ~ (all equal)
EncoderEncode 0.00B 0.00B ~ (all equal)
name old allocs/op new allocs/op delta
CodeEncoder 0.00 0.00 ~ (all equal)
CodeEncoderError 4.00 ± 0% 4.00 ± 0% ~ (all equal)
CodeMarshal 1.00 ± 0% 1.00 ± 0% ~ (all equal)
CodeMarshalError 6.00 ± 0% 6.00 ± 0% ~ (all equal)
EncodeMarshaler 1.00 ± 0% 1.00 ± 0% ~ (all equal)
EncoderEncode 0.00 0.00 ~ (all equal)
There is a very slight performance degradation for CodeEncoder
due to an increase in allocation sizes. However, the number of allocations
did not change. This is likely due to remote effects of the growth rate
differences between bytes.Buffer and the builtin append function.
We shouldn't overly rely on the growth rate of bytes.Buffer anyways
since that is subject to possibly change in #51462.
As the benchtime increases, the alloc/op goes down indicating
that the amortized memory cost is fixed.
Updates #27735
Change-Id: Ie35e480e292fe082d7986e0a4d81212c1d4202b3
Reviewed-on: https://go-review.googlesource.com/c/go/+/469556
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This is part of the effort to reduce direct reliance on bytes.Buffer
so that we can use a buffer with better pooling characteristics.
Avoid direct use of bytes.Buffer in Compact and Indent and
instead modify the logic to rely only on append.
This avoids reliance on the bytes.Buffer.Truncate method,
which makes switching to a custom buffer implementation easier.
Performance:
name old time/op new time/op delta
EncodeMarshaler 25.5ns ± 8% 25.7ns ± 9% ~ (p=0.724 n=10+10)
name old alloc/op new alloc/op delta
EncodeMarshaler 4.00B ± 0% 4.00B ± 0% ~ (all equal)
name old allocs/op new allocs/op delta
EncodeMarshaler 1.00 ± 0% 1.00 ± 0% ~ (all equal)
Updates #27735
Change-Id: I8cded03fab7651d43b5a238ee721f3472530868e
Reviewed-on: https://go-review.googlesource.com/c/go/+/469555
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Change-Id: I69065f8adf101fdb28682c55997f503013a50e29
Reviewed-on: https://go-review.googlesource.com/c/go/+/449757
Auto-Submit: Ian Lance Taylor <iant@google.com>
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Change-Id: I4698d0fa78108d83ee91732e8d3878dbff7f9c90
Reviewed-on: https://go-review.googlesource.com/c/go/+/436711
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Change-Id: Ib07699df8ea41fd8d1bca8ad050859fac24623de
Reviewed-on: https://go-review.googlesource.com/c/go/+/428258
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Change-Id: I5987eed00ee825421abe62699a06e9b66499f35f
Reviewed-on: https://go-review.googlesource.com/c/go/+/425016
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occurs
name old time/op new time/op delta
CodeEncoderError-10 688µs ± 8% 496µs ±15% -27.92% (p=0.000 n=10+9)
CodeMarshalError-10 747µs ± 6% 546µs ± 4% -26.86% (p=0.000 n=10+10)
MarshalBytesError/32-10 284µs ± 2% 273µs ± 1% -3.84% (p=0.000 n=10+10)
MarshalBytesError/256-10 281µs ± 2% 278µs ± 4% ~ (p=0.053 n=9+10)
MarshalBytesError/4096-10 290µs ± 1% 279µs ± 3% -3.52% (p=0.000 n=10+10)
name old speed new speed delta
CodeEncoderError-10 2.83GB/s ± 8% 3.84GB/s ±20% +36.03% (p=0.000 n=10+10)
CodeMarshalError-10 2.60GB/s ± 5% 3.56GB/s ± 4% +36.61% (p=0.000 n=10+10)
name old alloc/op new alloc/op delta
CodeEncoderError-10 4.05MB ± 1% 0.00MB ± 1% -100.00% (p=0.000 n=10+9)
CodeMarshalError-10 6.05MB ± 0% 1.99MB ± 1% -67.13% (p=0.000 n=10+10)
MarshalBytesError/32-10 66.0kB ± 0% 0.2kB ± 0% -99.67% (p=0.000 n=9+8)
MarshalBytesError/256-10 50.1kB ± 0% 0.9kB ± 0% -98.23% (p=0.000 n=9+9)
MarshalBytesError/4096-10 87.4kB ± 0% 7.5kB ± 0% -91.47% (p=0.000 n=8+10)
name old allocs/op new allocs/op delta
CodeEncoderError-10 25.0 ± 0% 4.0 ± 0% -84.00% (p=0.000 n=9+10)
CodeMarshalError-10 27.0 ± 0% 6.0 ± 0% -77.78% (p=0.000 n=10+10)
MarshalBytesError/32-10 18.0 ± 0% 5.0 ± 0% -72.22% (p=0.000 n=10+10)
MarshalBytesError/256-10 17.0 ± 0% 6.0 ± 0% -64.71% (p=0.000 n=10+10)
MarshalBytesError/4096-10 16.0 ± 0% 6.0 ± 0% -62.50% (p=0.000 n=10+10)
Change-Id: I48070bb05f55707251c694e40d2570403bbf61f8
Reviewed-on: https://go-review.googlesource.com/c/go/+/423694
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Change-Id: I50e5609ff9c5f2b216b93cec7fb5214d196cae90
Reviewed-on: https://go-review.googlesource.com/c/go/+/412537
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Change-Id: I71c9d9ef9d21a7ae9466d8c7b283fdfbba01f5a8
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[This CL is part of a sequence implementing the proposal #51082.
The design doc is at https://go.dev/s/godocfmt-design.]
Run the updated gofmt, which reformats doc comments,
on the main repository. Vendored files are excluded.
For #51082.
Change-Id: I7332f099b60f716295fb34719c98c04eb1a85407
Reviewed-on: https://go-review.googlesource.com/c/go/+/384268
Reviewed-by: Jonathan Amsterdam <jba@google.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
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go/doc in all its forms applies this replacement when rendering
the comments. We are considering formatting doc comments,
including doing this replacement as part of the formatting.
Apply it to our source files ahead of time.
For #51082.
Change-Id: Ifcc1f5861abb57c5d14e7d8c2102dfb31b7a3a19
Reviewed-on: https://go-review.googlesource.com/c/go/+/384262
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A future change to gofmt will rewrite
// Doc comment.
//
func f()
to
// Doc comment.
func f()
Apply that change preemptively to all doc comments.
For #51082.
Change-Id: I4023e16cfb0729b64a8590f071cd92f17343081d
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The latter returns a uintptr, while the former returns a unsafe.Pointer.
A uintptr is unsafe if Go ever switches to a moving GC,
while a unsafe.Pointer will be properly tracked by the GC.
We do not use unsafe.Pointer for any unsafe type conversions,
and only use it for comparability purposes, which is relatively safe.
Updates #40592
Change-Id: I813e218668704b63a3043acda4331205a3835a66
Reviewed-on: https://go-review.googlesource.com/c/go/+/360855
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Adds simple fuzz targets to archive/tar, archive/zip, compress/gzip,
encoding/json, image/jpeg, image/gif, and image/png.
Second attempt, this time we don't use the archives in testdata when
fuzzing archive/tar, since those are rather memory intensive, and
were crashing a number of builders.
Change-Id: I4828d64fa4763c0d8c980392a6578e4dfd956e13
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This reverts CL 352109.
Reason for revert: causing OOM failures on several builders, and may cause OOMs for end users with small machines as well.
Change-Id: I58308d09919969d5a6512ee5cee6aa5c4af6769b
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Adds simple fuzz targets to archive/tar, archive/zip, compress/gzip,
encoding/json, image/jpeg, image/gif, and image/png.
Change-Id: Ide1a8de88a9421e786eeeaea3bb93f41e0bae347
Reviewed-on: https://go-review.googlesource.com/c/go/+/352109
Trust: Katie Hockman <katie@golang.org>
Reviewed-by: Katie Hockman <katie@golang.org>
Trust: Roland Shoemaker <roland@golang.org>
Run-TryBot: Roland Shoemaker <roland@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
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And then revert the bootstrap cmd directories and certain testdata.
And adjust tests as needed.
Not reverting the changes in std that are bootstrapped,
because some of those changes would appear in API docs,
and we want to use any consistently.
Instead, rewrite 'any' to 'interface{}' in cmd/dist for those directories
when preparing the bootstrap copy.
A few files changed as a result of running gofmt -w
not because of interface{} -> any but because they
hadn't been updated for the new //go:build lines.
Fixes #49884.
Change-Id: Ie8045cba995f65bd79c694ec77a1b3d1fe01bb09
Reviewed-on: https://go-review.googlesource.com/c/go/+/368254
Trust: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
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When these packages are released as part of Go 1.18,
Go 1.16 will no longer be supported, so we can remove
the +build tags in these files.
Ran go fix -fix=buildtag std cmd and then reverted the bootstrapDirs
as defined in src/cmd/dist/buildtool.go, which need to continue
to build with Go 1.4 for now.
Also reverted src/vendor and src/cmd/vendor, which will need
to be updated in their own repos first.
Manual changes in runtime/pprof/mprof_test.go to adjust line numbers.
For #41184.
Change-Id: Ic0f93f7091295b6abc76ed5cd6e6746e1280861e
Reviewed-on: https://go-review.googlesource.com/c/go/+/344955
Trust: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
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Updates #47651
Updates #48665
Change-Id: I69a87b45a5cad7a07fbd855040cd9935cf874554
Reviewed-on: https://go-review.googlesource.com/c/go/+/358454
Trust: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
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Many uses of Index/IndexByte/IndexRune/Split/SplitN
can be written more clearly using the new Cut functions.
Do that. Also rewrite to other functions if that's clearer.
For #46336.
Change-Id: I68d024716ace41a57a8bf74455c62279bde0f448
Reviewed-on: https://go-review.googlesource.com/c/go/+/351711
Trust: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
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Reviewed-by: Ian Lance Taylor <iant@golang.org>
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Prior to this CL, pasting the example from the website causes a
compilation error for some programs because it was shadowing the
"json" package.
Change-Id: I39b68a66ca99468547f2027a7655cf1387b61e95
Reviewed-on: https://go-review.googlesource.com/c/go/+/301492
Reviewed-by: Joe Tsai <joetsai@google.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Trust: Joe Tsai <joetsai@google.com>
Run-TryBot: Joe Tsai <joetsai@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
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Map serialization using reflect.Value.MapIndex cannot retrieve
map keys that contain a NaN, resulting in a panic.
Switch the implementation to use the reflect.Value.MapRange method
instead, which iterates over all map entries regardless of whether
they are directly retrievable.
Note that according to RFC 8259, section 4, a JSON object should
have unique names, but does not forbid the occurrence of duplicate names.
Fixes #43207
Change-Id: If4bc55229b1f64b8ca4b0fed37549725efdace39
Reviewed-on: https://go-review.googlesource.com/c/go/+/278632
Trust: Meng Zhuo <mzh@golangcn.org>
Trust: Joe Tsai <thebrokentoaster@gmail.com>
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Run-TryBot: Meng Zhuo <mzh@golangcn.org>
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The IsExported method is a more intuitive helper for checking whether
the method or field is exported than checking whether PkgPath is empty.
In the same CL, modify the standard library to make use of this helper.
Fixes #41563
Change-Id: Iaacfb3b74449501f98e2707aa32095a32bd3c3c1
Reviewed-on: https://go-review.googlesource.com/c/go/+/266197
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The decodeState type is a large part of the allocated space during Unmarshal.
The errorContext field is infrequently used, and only on error.
Extract it into a pointer and allocate it separate when necessary.
name old time/op new time/op delta
UnmarshalString-8 115ns ± 5% 114ns ± 3% ~ (p=0.170 n=15+15)
UnmarshalFloat64-8 113ns ± 2% 106ns ± 1% -6.42% (p=0.000 n=15+14)
UnmarshalInt64-8 93.3ns ± 1% 86.9ns ± 4% -6.89% (p=0.000 n=14+15)
name old alloc/op new alloc/op delta
UnmarshalString-8 192B ± 0% 160B ± 0% -16.67% (p=0.000 n=15+15)
UnmarshalFloat64-8 180B ± 0% 148B ± 0% -17.78% (p=0.000 n=15+15)
UnmarshalInt64-8 176B ± 0% 144B ± 0% -18.18% (p=0.000 n=15+15)
name old allocs/op new allocs/op delta
UnmarshalString-8 2.00 ± 0% 2.00 ± 0% ~ (all equal)
UnmarshalFloat64-8 2.00 ± 0% 2.00 ± 0% ~ (all equal)
UnmarshalInt64-8 1.00 ± 0% 1.00 ± 0% ~ (all equal)
Change-Id: I53f3f468e6c65f77a12e5138a2626455b197012d
Reviewed-on: https://go-review.googlesource.com/c/go/+/271338
Trust: Josh Bleecher Snyder <josharian@gmail.com>
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Make all our package sources use Go 1.17 gofmt format
(adding //go:build lines).
Part of //go:build change (#41184).
See https://golang.org/design/draft-gobuild
Change-Id: Ia0534360e4957e58cd9a18429c39d0e32a6addb4
Reviewed-on: https://go-review.googlesource.com/c/go/+/294430
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This reverts commit 6af088bfc66c13143c9ef46b4cf0805df77a8fbe.
Reason for revert: Broke many tests inside Google which implies many
tests were broken outside of Google as well. The tests may be brittle
but still would require work to change and it's not clear it's worth
the benefit.
Updates #36221
Fixes #42675
Change-Id: Id3a14eb37e7119f5abe50e80dfbf120fdc44db72
Reviewed-on: https://go-review.googlesource.com/c/go/+/273747
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The other named errors - UnmarshalTypeError, etc - in this package do
the same, so we should prepend the package prefix to error messages
for consistency.
Add a note to the release docs in case this is interpreted as
a breaking change.
Fixes #36221.
Change-Id: Ie24b532bbf9812e108c259fa377e2a6b64319ed4
Reviewed-on: https://go-review.googlesource.com/c/go/+/263619
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The old ioutil references are still valid, but update our code
to reflect best practices and get used to the new locations.
Code compiled with the bootstrap toolchain
(cmd/asm, cmd/dist, cmd/compile, debug/elf)
must remain Go 1.4-compatible and is excluded.
Also excluded vendored code.
For #41190.
Change-Id: I6d86f2bf7bc37a9d904b6cee3fe0c7af6d94d5b1
Reviewed-on: https://go-review.googlesource.com/c/go/+/263142
Trust: Russ Cox <rsc@golang.org>
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Added godoc to UnsupportedValueError.
Change-Id: I5fc13bac0b6e14b3a6eba27c9d3331ff5c5269aa
GitHub-Last-Rev: 516cd7a92903e1048caa4d560abf5d66339e5a8f
GitHub-Pull-Request: golang/go#41364
Reviewed-on: https://go-review.googlesource.com/c/go/+/254540
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Trust: Daniel Martí <mvdan@mvdan.cc>
Trust: Heschi Kreinick <heschi@google.com>
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Now reports an error if cyclic maps and slices are to be encoded
instead of an infinite recursion. This case wasn't handled in CL 187920.
Fixes #40745.
Change-Id: Ia34b014ecbb71fd2663bb065ba5355a307dbcc15
GitHub-Last-Rev: 6f874944f4065b5237babbb0fdce14c1c74a3c97
GitHub-Pull-Request: golang/go#40756
Reviewed-on: https://go-review.googlesource.com/c/go/+/248358
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
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Allow ';' as a valid character for json field keys and struct tags.
Fixes #39189
Change-Id: I4b602a1b0674ff028db07623682f0d1e8e9fd6c9
Reviewed-on: https://go-review.googlesource.com/c/go/+/234818
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This reverts CL 253037.
Reason for revert: The recommended way to check for a type of error is errors.As. API changes should also start with a proposal.
Change-Id: I62896717aa47ed491c2c4775d2b05d80e5e9cde3
Reviewed-on: https://go-review.googlesource.com/c/go/+/254837
Trust: Damien Neil <dneil@google.com>
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
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This reverts CL 254537.
Reason for revert: Reason for revert: The recommended way to check for a type of error is errors.As. API changes should also start with a proposal.
Change-Id: I07c37428575e99c80b17525833a61831d10963bb
Reviewed-on: https://go-review.googlesource.com/c/go/+/254857
Trust: Damien Neil <dneil@google.com>
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
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Allows users to check:
errors.Is(err, &UnmarshalTypeError{})
errors.Is(err, &UnmarshalFieldError{})
errors.Is(err, &InvalidUnmarshalError{})
errors.Is(err, &UnsupportedValueError{})
errors.Is(err, &MarshalerError{})
which is the recommended way of checking for kinds of errors.
SyntaxError.Is was implemented in CL 253037.
As and Unwrap relevant methods will be added in future CLs.
Change-Id: I1f8a503b8fdc0f3afdfe9669a91f3af8d960e028
GitHub-Last-Rev: 930cda5384c987a0b31f277ba3b4ab690ea74ac3
GitHub-Pull-Request: golang/go#41360
Reviewed-on: https://go-review.googlesource.com/c/go/+/254537
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Allows users to check:
errors.Is(err, &json.SyntaxError{})
which is the recommended way of checking for kinds of errors.
Change-Id: I20dc805f20212765e9936a82d9cb7822e73ec4ef
GitHub-Last-Rev: e2627ccf8e2a00cc3459bb9fee86c3c8675a33af
GitHub-Pull-Request: golang/go#41210
Reviewed-on: https://go-review.googlesource.com/c/go/+/253037
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This reverts https://golang.org/cl/191783.
Reason for revert: Broke too many programs which depended on the previous
behavior, even when it was the opposite of what the documentation said.
We can attempt to fix the original issue again for 1.16, while keeping
those programs in mind.
Fixes #39427.
Change-Id: I7a7f24b2a594c597ef625aeff04fff29aaa88fc6
Reviewed-on: https://go-review.googlesource.com/c/go/+/240657
Run-TryBot: Dmitri Shuralyov <dmitshur@golang.org>
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This reverts golang.org/cl/190659 and golang.org/cl/226218, minus the
regression tests in the latter.
The original work happened in golang.org/cl/151157, which was reverted
in golang.org/cl/190909 due to a crash found by fuzzing.
We tried a second time in golang.org/cl/190659, which shipped with Go
1.14. A bug was found, where strings would be mangled in certain edge
cases. The fix for that was golang.org/cl/226218, which was backported
into Go 1.14.4.
Unfortunately, a second regression was just reported in #39555, which is
a similar case of strings getting mangled when decoding under certain
conditions. It would be possible to come up with another small patch to
fix that edge case, but instead, let's just revert the entire
optimization, as it has proved to do more harm than good. Moreover, it's
hard to argue or prove that there will be no more such regressions.
However, all the work wasn't for nothing. First, we learned that the way
the decoder unquotes tokenized strings isn't simple; initially, we had
wrongly assumed that each string was unquoted exactly once and in order.
Second, we have gained a number of regression tests which will be useful
to prevent the same mistakes in the future, including the test cases we
add in this CL.
Fixes #39555.
Change-Id: I66a6919c2dd6d9789232482ba6cf3814eaa70f61
Reviewed-on: https://go-review.googlesource.com/c/go/+/237838
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This reverts golang.org/cl/179337.
Reason for revert: broke a few too many reasonably valid Go programs.
The previous behavior was perhaps less consistent, but the docs were
never very clear about when the decoder merges with existing values,
versus replacing existing values altogether.
Fixes #39149.
Change-Id: I1c1d857709b8398969fe421aa962f6b62f91763a
Reviewed-on: https://go-review.googlesource.com/c/go/+/234559
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
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When we decode into a struct, each input key-value may be decoded into
one of the struct's fields. Particularly, existing data isn't dropped,
so that some sub-fields can be decoded into without zeroing all other
data.
However, decoding into a map behaved in the opposite way. Whenever a
key-value was decoded, it completely replaced the previous map element.
If the map contained any non-zero data in that key, it's dropped.
Instead, try to reuse the existing element value if possible. If the map
element type is a pointer, and the value is non-nil, we can decode
directly into it. If it's not a pointer, make a copy and decode into
that copy, as map element values aren't addressable.
This means we have to parse and convert the map element key before the
value, to be able to obtain the existing element value. This is fine,
though. Moreover, reporting errors on the key before the value follows
the input order more closely.
Finally, add a test to explore the four combinations, involving pointer
and non-pointer, and non-zero and zero values. A table-driven test
wasn't used, as each case required different checks, such as checking
that the non-nil pointer case doesn't end up with a different pointer.
Fixes #31924.
Change-Id: I5ca40c9963a98aaf92f26f0b35843c021028dfca
Reviewed-on: https://go-review.googlesource.com/c/go/+/179337
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The added comment contains some context. The original optimization
assumed that each call to unquoteBytes (or unquote) followed its
corresponding call to rescanLiteral. Otherwise, unquoting a literal
might use d.safeUnquote from another re-scanned literal.
Unfortunately, this assumption is wrong. When decoding {"foo": "bar"}
into a map[T]string where T implements TextUnmarshaler, the sequence of
calls would be as follows:
1) rescanLiteral "foo"
2) unquoteBytes "foo"
3) rescanLiteral "bar"
4) unquoteBytes "foo" (for UnmarshalText)
5) unquoteBytes "bar"
Note that the call to UnmarshalText happens in literalStore, which
repeats the work to unquote the input string literal. But, since that
happens after we've re-scanned "bar", we're using the wrong safeUnquote
field value.
In the added test case, the second string had a non-zero number of safe
bytes, and the first string had none since it was all non-ASCII. Thus,
"safely" unquoting a number of the first string's bytes could cut a rune
in half, and thus mangle the runes.
A rather simple fix, without a full revert, is to only allow one use of
safeUnquote per call to unquoteBytes. Each call to rescanLiteral when
we have a string is soon followed by a call to unquoteBytes, so it's no
longer possible for us to use the wrong index.
Also add a test case from #38126, which is the same underlying bug, but
affecting the ",string" option.
Before the fix, the test would fail, just like in the original two issues:
--- FAIL: TestUnmarshalRescanLiteralMangledUnquote (0.00s)
decode_test.go:2443: Key "开源" does not exist in map: map[开���:12345开源]
decode_test.go:2458: Unmarshal unexpected error: json: invalid use of ,string struct tag, trying to unmarshal "\"aaa\tbbb\"" into string
Fixes #38105.
For #38126.
Change-Id: I761e54924e9a971a4f9eaa70bbf72014bb1476e6
Reviewed-on: https://go-review.googlesource.com/c/go/+/226218
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golang.org/cl/193604 fixed one bug when one encodes a string with the
",string" option: if SetEscapeHTML(false) is used, we should not be
using HTML escaping for the inner string encoding. The CL correctly
fixed that.
The CL also tried to speed up this edge case. By avoiding an entire new
call to Marshal, the new Issue34127 benchmark reduced its time/op by
45%, and lowered the allocs/op from 3 to 2.
However, that last optimization wasn't correct:
Since Go 1.2 every string can be marshaled to JSON without error
even if it contains invalid UTF-8 byte sequences. Therefore
there is no need to use Marshal again for the only reason of
enclosing the string in double quotes.
JSON string encoding isn't just about adding quotes and taking care of
invalid UTF-8. We also need to escape some characters, like tabs and
newlines.
The new code failed to do that. The bug resulted in the added test case
failing to roundtrip properly; before our fix here, we'd see an error:
invalid use of ,string struct tag, trying to unmarshal "\"\b\f\n\r\t\"\\\"" into string
If you pay close attention, you'll notice that the special characters
like tab and newline are only encoded once, not twice. When decoding
with the ",string" option, the outer string decode works, but the inner
string decode fails, as we are now decoding a JSON string with unescaped
special characters.
The fix we apply here isn't to go back to Marshal, as that would
re-introduce the bug with SetEscapeHTML(false). Instead, we can use a
new encode state from the pool - it results in minimal performance
impact, and even reduces allocs/op further. The performance impact seems
fair, given that we need to check the entire string for characters that
need to be escaped.
name old time/op new time/op delta
Issue34127-8 89.7ns ± 2% 100.8ns ± 1% +12.27% (p=0.000 n=8+8)
name old alloc/op new alloc/op delta
Issue34127-8 40.0B ± 0% 32.0B ± 0% -20.00% (p=0.000 n=8+8)
name old allocs/op new allocs/op delta
Issue34127-8 2.00 ± 0% 1.00 ± 0% -50.00% (p=0.000 n=8+8)
Instead of adding another standalone test, we convert an existing
"string tag" test to be table-based, and add another test case there.
One test case from the original CL also had to be amended, due to the
same problem - when escaping '<' due to SetEscapeHTML(true), we need to
end up with double escaping, since we're using ",string".
Fixes #38173.
Change-Id: I2b0df9e4f1d3452fff74fe910e189c930dde4b5b
Reviewed-on: https://go-review.googlesource.com/c/go/+/226498
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The previous behavior directly contradicted the docs that have been in
place for years:
To unmarshal a JSON array into a slice, Unmarshal resets the
slice length to zero and then appends each element to the slice.
We could use reflect.New to create a new element and reflect.Append to
then append it to the destination slice, but benchmarks have shown that
reflect.Append is very slow compared to the code that manually grows a
slice in this file.
Instead, if we're decoding into an element that came from the original
backing array, zero it before decoding into it. We're going to be using
the CodeDecoder benchmark, as it has a slice of struct pointers that's
decoded very often.
Note that we still reuse existing values from arrays being decoded into,
as the documentation agrees with the existing implementation in that
case:
To unmarshal a JSON array into a Go array, Unmarshal decodes
JSON array elements into corresponding Go array elements.
The numbers with the benchmark as-is might seem catastrophic, but that's
only because the benchmark is decoding into the same variable over and
over again. Since the old decoder was happy to reuse slice elements, it
would save a lot of allocations by not having to zero and re-allocate
said elements:
name old time/op new time/op delta
CodeDecoder-8 10.4ms ± 1% 10.9ms ± 1% +4.41% (p=0.000 n=10+10)
name old speed new speed delta
CodeDecoder-8 186MB/s ± 1% 178MB/s ± 1% -4.23% (p=0.000 n=10+10)
name old alloc/op new alloc/op delta
CodeDecoder-8 2.19MB ± 0% 3.59MB ± 0% +64.09% (p=0.000 n=10+10)
name old allocs/op new allocs/op delta
CodeDecoder-8 76.8k ± 0% 92.7k ± 0% +20.71% (p=0.000 n=10+10)
We can prove this by moving 'var r codeResponse' into the loop, so that
the benchmark no longer reuses the destination pointer. And sure enough,
we no longer see the slow-down caused by the extra allocations:
name old time/op new time/op delta
CodeDecoder-8 10.9ms ± 0% 10.9ms ± 1% -0.37% (p=0.043 n=10+10)
name old speed new speed delta
CodeDecoder-8 177MB/s ± 0% 178MB/s ± 1% +0.37% (p=0.041 n=10+10)
name old alloc/op new alloc/op delta
CodeDecoder-8 3.59MB ± 0% 3.59MB ± 0% ~ (p=0.780 n=10+10)
name old allocs/op new allocs/op delta
CodeDecoder-8 92.7k ± 0% 92.7k ± 0% ~ (all equal)
I believe that it's useful to leave the benchmarks as they are now,
because the decoder does reuse memory in some cases. For example,
existing map elements are reused. However, subtle changes like this one
need to be benchmarked carefully.
Finally, add a couple of tests involving both a slice and an array of
structs.
Fixes #21092.
Change-Id: I8b1194f25e723a31abd146fbfe9428ac10c1389d
Reviewed-on: https://go-review.googlesource.com/c/go/+/191783
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
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