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57 commits

Author SHA1 Message Date
Filippo Valsorda
eee07a8e68 Revert "encoding/json: avoid work when unquoting strings"
This reverts CL 151157.

CL 151157 introduced a crash when decoding into ",string" fields. It
came with a moderate speedup, so at this stage of the release cycle
let's just revert it, and reapply it in Go 1.14 with the fix in CL 190659.

Also applied the test cases from CL 190659.

Updates #33728

Change-Id: Ie46e2bc15224b251888580daf6b79d5865f3878e
Reviewed-on: https://go-review.googlesource.com/c/go/+/190909
Run-TryBot: Andrew Bonventre <andybons@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Andrew Bonventre <andybons@golang.org>
2019-08-21 15:20:00 +00:00
LE Manh Cuong
dcb84828a6 encoding/json: fix Unmarshal hang on recursive pointers
indirect walks down v until it gets to a non-pointer. But it does not
handle the case when v is a pointer to itself, like in:

	var v interface{}
	v = &v
	Unmarshal(b, v)

So just stop immediately if we see v is a pointer to itself.

Fixes #31740

Change-Id: Ie396264119e24d70284cd9bf76dcb2050babb069
Reviewed-on: https://go-review.googlesource.com/c/go/+/174337
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2019-04-30 04:57:42 +00:00
Daniel Martí
7e08c7f43d encoding/json: index names for the struct decoder
In the common case, structs have a handful of fields and most inputs
match struct field names exactly.

The previous code would do a linear search over the fields, stopping at
the first exact match, and otherwise using the first case insensitive
match.

This is unfortunate, because it means that for the common case, we'd do
a linear search with bytes.Equal. Even for structs with only two or
three fields, that is pretty wasteful.

Worse even, up until the exact match was found via the linear search,
all previous fields would run their equalFold functions, which aren't
cheap even in the simple case.

Instead, cache a map along with the field list that indexes the fields
by their name. This way, a case sensitive field search doesn't involve a
linear search, nor does it involve any equalFold func calls.

This patch should also slightly speed up cases where there's a case
insensitive match but not a case sensitive one, as then we'd avoid
calling bytes.Equal on all the fields. Though that's not a common case,
and there are no benchmarks for it.

name           old time/op    new time/op    delta
CodeDecoder-8    11.0ms ± 0%    10.6ms ± 1%  -4.42%  (p=0.000 n=9+10)

name           old speed      new speed      delta
CodeDecoder-8   176MB/s ± 0%   184MB/s ± 1%  +4.62%  (p=0.000 n=9+10)

name           old alloc/op   new alloc/op   delta
CodeDecoder-8    2.28MB ± 0%    2.28MB ± 0%    ~     (p=0.725 n=10+10)

name           old allocs/op  new allocs/op  delta
CodeDecoder-8     76.9k ± 0%     76.9k ± 0%    ~     (all equal)

Updates #28923.

Change-Id: I9929c1f06c76505e5b96914199315dbdaae5dc76
Reviewed-on: https://go-review.googlesource.com/c/go/+/172918
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2019-04-23 05:54:51 +00:00
Daniel Martí
fe1afe8d4c encoding/json: avoid work when unquoting strings
We can work out how many bytes can be unquoted trivially in
rescanLiteral, which already iterates over a string's bytes.

Removing the extra loop in unquoteBytes simplifies the function and
speeds it up, especially when decoding simple strings, which are common.

While at it, we can remove unnecessary checks like len(s)<2 and
s[0]=='"'. Add a comment explaining why.

name           old time/op    new time/op    delta
CodeDecoder-8    11.2ms ± 0%    11.1ms ± 1%  -1.63%  (p=0.000 n=9+10)

name           old speed      new speed      delta
CodeDecoder-8   173MB/s ± 0%   175MB/s ± 1%  +1.66%  (p=0.000 n=9+10)

Updates #28923.

Change-Id: I2436a3a7f8148a2f7a6a4cdbd7dec6b32ef5e20c
Reviewed-on: https://go-review.googlesource.com/c/go/+/151157
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2019-04-22 15:07:38 +00:00
Daniel Martí
2cc17bc5f2 encoding/json: speed up tokenization of literals
Decoder.Decode and Unmarshal actually scan the input bytes twice - the
first time to check for syntax errors and the length of the value, and
the second to perform the decoding.

It's in the second scan that we actually tokenize the bytes. Since
syntax errors aren't a possibility, we can take shortcuts.

In particular, literals such as quoted strings are very common in JSON,
so we can avoid a lot of work by special casing them.

name                  old time/op    new time/op    delta
CodeDecoder-8           10.3ms ± 1%     9.1ms ± 0%  -11.89%  (p=0.002 n=6+6)
UnicodeDecoder-8         342ns ± 0%     283ns ± 0%  -17.25%  (p=0.000 n=6+5)
DecoderStream-8          239ns ± 0%     230ns ± 0%   -3.90%  (p=0.000 n=6+5)
CodeUnmarshal-8         11.0ms ± 0%     9.8ms ± 0%  -11.45%  (p=0.002 n=6+6)
CodeUnmarshalReuse-8    10.3ms ± 0%     9.0ms ± 0%  -12.72%  (p=0.004 n=5+6)
UnmarshalString-8        104ns ± 0%      92ns ± 0%  -11.35%  (p=0.002 n=6+6)
UnmarshalFloat64-8      93.2ns ± 0%    87.6ns ± 0%   -6.01%  (p=0.010 n=6+4)
UnmarshalInt64-8        74.5ns ± 0%    71.5ns ± 0%   -3.91%  (p=0.000 n=5+6)

name                  old speed      new speed      delta
CodeDecoder-8          189MB/s ± 1%   214MB/s ± 0%  +13.50%  (p=0.002 n=6+6)
UnicodeDecoder-8      40.9MB/s ± 0%  49.5MB/s ± 0%  +20.96%  (p=0.002 n=6+6)
CodeUnmarshal-8        176MB/s ± 0%   199MB/s ± 0%  +12.93%  (p=0.002 n=6+6)

Updates #28923.

Change-Id: I7a5e2aef51bd4ddf2004aad24210f6f50e01eaeb
Reviewed-on: https://go-review.googlesource.com/c/go/+/151042
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2019-04-03 17:01:44 +00:00
Daniel Martí
e5f6e2d1c8 encoding/json: fix performance regression in the decoder
In golang.org/cl/145218, a feature was added where the JSON decoder
would keep track of the entire path to a field when reporting an
UnmarshalTypeError.

However, we all failed to check if this affected the benchmarks - myself
included, as a reviewer. Below are the numbers comparing the CL's parent
with itself, once it was merged:

name           old time/op    new time/op    delta
CodeDecoder-8    12.9ms ± 1%    28.2ms ± 2%   +119.33%  (p=0.002 n=6+6)

name           old speed      new speed      delta
CodeDecoder-8   151MB/s ± 1%    69MB/s ± 3%    -54.40%  (p=0.002 n=6+6)

name           old alloc/op   new alloc/op   delta
CodeDecoder-8    2.74MB ± 0%  109.39MB ± 0%  +3891.83%  (p=0.002 n=6+6)

name           old allocs/op  new allocs/op  delta
CodeDecoder-8     77.5k ± 0%    168.5k ± 0%   +117.30%  (p=0.004 n=6+5)

The reason why the decoder got twice as slow is because it now allocated
~40x as many objects, which puts a lot of pressure on the garbage
collector.

The reason is that the CL concatenated strings every time a nested field
was decoded. In other words, practically every field generated garbage
when decoded. This is hugely wasteful, especially considering that the
vast majority of JSON decoding inputs won't return UnmarshalTypeError.

Instead, use a stack of fields, and make sure to always use the same
backing array, to ensure we only need to grow the slice to the maximum
depth once.

The original CL also introduced a bug. The field stack string wasn't
reset to its original state when reaching "d.opcode == scanEndObject",
so the last field in a decoded struct could leak. For example, an added
test decodes a list of structs, and encoding/json before this CL would
fail:

	got:  cannot unmarshal string into Go struct field T.Ts.Y.Y.Y of type int
	want: cannot unmarshal string into Go struct field T.Ts.Y of type int

To fix that, simply reset the stack after decoding every field, even if
it's the last.

Below is the original performance versus this CL. There's a tiny
performance hit, probably due to the append for every decoded field, but
at least we're back to the usual ~150MB/s.

name           old time/op    new time/op    delta
CodeDecoder-8    12.9ms ± 1%    13.0ms ± 1%  +1.25%  (p=0.009 n=6+6)

name           old speed      new speed      delta
CodeDecoder-8   151MB/s ± 1%   149MB/s ± 1%  -1.24%  (p=0.009 n=6+6)

name           old alloc/op   new alloc/op   delta
CodeDecoder-8    2.74MB ± 0%    2.74MB ± 0%  +0.00%  (p=0.002 n=6+6)

name           old allocs/op  new allocs/op  delta
CodeDecoder-8     77.5k ± 0%     77.5k ± 0%  +0.00%  (p=0.002 n=6+6)

Finally, make all of these benchmarks report allocs by default. The
decoder ones are pretty sensitive to generated garbage, so ReportAllocs
would have made the performance regression more obvious.

Change-Id: I67b50f86b2e72f55539429450c67bfb1a9464b67
Reviewed-on: https://go-review.googlesource.com/c/go/+/167978
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2019-03-18 07:58:23 +00:00
LE Manh Cuong
29bc4f1258 encoding/json: add Path to UnmarshalTypeError
When parsing nested object, UnmarshalTypeError does not contain actual
path to nested field in original JSON.

This commit change Field to contain the full path to that field. One
can get the Field name by stripping all the leading path elements.

Fixes #22369

Change-Id: I6969cc08abe8387a351e3fb2944adfaa0dccad2a
Reviewed-on: https://go-review.googlesource.com/c/go/+/145218
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2019-03-05 12:34:11 +00:00
Daniel Martí
4b36e129f8 encoding/json: always verify we can get a field's value
Calling .Interface on a struct field's reflect.Value isn't always safe.
For example, if that field is an unexported anonymous struct.

We only descended into this branch if the struct type had any methods,
so this bug had gone unnoticed for a few release cycles.

Add the check, and add a simple test case.

Fixes #28145.

Change-Id: I02f7e0ab9a4a0c18a5e2164211922fe9c3d30f64
Reviewed-on: https://go-review.googlesource.com/c/141537
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-10-16 14:02:52 +00:00
Daniel Martí
5eff6bfdbc encoding/json: fix "data changed underfoot?" panic
Given a program as follows:

	data := []byte(`{"F": {
		"a": 2,
		"3": 4
	}}`)
	json.Unmarshal(data, &map[string]map[int]int{})

The JSON package should error, as "a" is not a valid integer. However,
we'd encounter a panic:

	panic: JSON decoder out of sync - data changing underfoot?

The reason was that decodeState.object would return a nil error on
encountering the invalid map key string, while saving the key type error
for later. This broke if we were inside another object, as we would
abruptly end parsing the nested object, leaving the decoder in an
unexpected state.

To fix this, simply avoid storing the map element and continue decoding
the object, to leave the decoder state exactly as if we hadn't seen an
invalid key type.

This affected both signed and unsigned integer keys, so fix both and add
two test cases.

Updates #28189.

Change-Id: I8a6204cc3ff9fb04ed769df7a20a824c8b94faff
Reviewed-on: https://go-review.googlesource.com/c/142518
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-10-16 13:45:08 +00:00
Daniel Martí
b2fcfc1a50 encoding/json: use panics for phase errors
Having these panic-like errors used to be ok, since they were used in
the internal decoder state instead of passed around via return
parameters.

Recently, the decoder was rewritten to use explicit error returns
instead. This error is a terrible fit for error returns; a handful of
functions must return an error because of it, and their callers must
check for an error that should never happen.

This is precisely what panics are for, so use them. The test coverage of
the package goes up from 91.3% to 91.6%, and performance is unaffected.
We can also get rid of some unnecessary verbosity in the code.

name           old time/op    new time/op    delta
CodeDecoder-4    27.5ms ± 1%    27.5ms ± 1%   ~     (p=0.937 n=6+6)

Change-Id: I01033b3f5b7c0cf0985082fa272754f96bf6353c
Reviewed-on: https://go-review.googlesource.com/134835
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
Run-TryBot: Joe Tsai <thebrokentoaster@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
2018-09-12 07:50:10 +00:00
Daniel Martí
dc3680865a encoding/json: more tests to cover decoding edge cases
The overall coverage of the json package goes up from 90.8% to 91.3%.

While at it, apply two minor code simplifications found while inspecting
the HTML coverage report.

Change-Id: I0fba968afeedc813b1385e4bde72d93b878854d7
Reviewed-on: https://go-review.googlesource.com/134735
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-09-12 06:48:09 +00:00
Ian Davis
22afb3571c encoding/json: recover saved error context when unmarshalling
Fixes: #27464

Change-Id: I270c56fd0d5ae8787a1293029aff3072f4f52f33
Reviewed-on: https://go-review.googlesource.com/132955
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-09-06 08:38:44 +00:00
Taesu Pyo
21e85c293d encoding/json: fix UnmarshalTypeError without field and struct values
Fixes #26444
Fixes #27275

Change-Id: I9e8cbff79f7643ca8964c572c1a98172b6831730
GitHub-Last-Rev: 7eea2158b6
GitHub-Pull-Request: golang/go#26719
Reviewed-on: https://go-review.googlesource.com/126897
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-08-28 16:00:33 +00:00
Daniel Martí
6d4787aff2 encoding/json: various minor decoder speed-ups
Reuse v.Type() and cachedTypeFields(t) when decoding maps and structs.

Always use the same data slices when in hot loops, to ensure that the
compiler generates good code. "for i < len(data) { use(d.data[i]) }"
makes it harder for the compiler.

Finally, do other minor clean-ups, such as deduplicating switch cases,
and using a switch instead of three chained ifs.

The decoder sees a noticeable speed-up, in particular when decoding
structs.

name           old time/op    new time/op    delta
CodeDecoder-4    29.8ms ± 1%    27.5ms ± 0%  -7.83%  (p=0.002 n=6+6)

name           old speed      new speed      delta
CodeDecoder-4  65.0MB/s ± 1%  70.6MB/s ± 0%  +8.49%  (p=0.002 n=6+6)

Updates #5683.

Change-Id: I9d751e22502221962da696e48996ffdeb777277d
Reviewed-on: https://go-review.googlesource.com/122468
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-08-21 19:00:08 +00:00
Daniel Martí
9a2a34e1c1 encoding/json: defer error context work until necessary
Calling Name on a reflect.Type is somewhat expensive, as it involves a
number of nested calls and string handling.

This cost was showing up when decoding structs, as we were calling it to
set up an error context.

We can avoid the extra work unless we do encounter an error, which makes
decoding via struct types faster.

name           old time/op    new time/op    delta
CodeDecoder-4    31.0ms ± 1%    29.9ms ± 1%  -3.69%  (p=0.002 n=6+6)

name           old speed      new speed      delta
CodeDecoder-4  62.6MB/s ± 1%  65.0MB/s ± 1%  +3.83%  (p=0.002 n=6+6)

Updates #5683.

Change-Id: I48a3a85ef0ba96f524b7c3e9096cb2c4589e077a
Reviewed-on: https://go-review.googlesource.com/122467
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-08-21 18:18:59 +00:00
Tim Cooper
dc272a4393 encoding/json: call reflect.TypeOf with nil pointers rather than allocating
Updates #26775

Change-Id: I83c9eeda59769d2f35e0cc98f3a8579861d5978b
Reviewed-on: https://go-review.googlesource.com/119715
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-08-21 02:38:02 +00:00
Tim Cooper
161874da2a all: update comment URLs from HTTP to HTTPS, where possible
Each URL was manually verified to ensure it did not serve up incorrect
content.

Change-Id: I4dc846227af95a73ee9a3074d0c379ff0fa955df
Reviewed-on: https://go-review.googlesource.com/115798
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
2018-06-01 21:52:00 +00:00
tengufromsky
c2a53b1b82 encoding/json: remove unnecessary if conditions
Fixes gosimple warning "if err != nil { return err };
return nil' can be simplified to 'return err"

Change-Id: Ife7f78a3a76ab7802b5561d1afec536e103b504a
Reviewed-on: https://go-review.googlesource.com/108275
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-04-20 01:41:41 +00:00
bontequero
568d4848f6 encoding/json: remove unnecessary else conditions
Fixes golint warning about "if block ends with a return statement, so drop this else and outdent its block".

Change-Id: Id17ad0bf37ba939386b177b709e9e3c067d8ba21
Reviewed-on: https://go-review.googlesource.com/105736
Run-TryBot: Iskander Sharipov <iskander.sharipov@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-04-09 19:28:23 +00:00
Pascal S. de Kloe
74a92b8e8d encoding/json: apply conventional error handling in decoder
name                            old time/op    new time/op    delta
CodeEncoder-12                    1.89ms ± 1%    1.91ms ± 0%   +1.16%  (p=0.000 n=20+19)
CodeMarshal-12                    2.09ms ± 1%    2.12ms ± 0%   +1.63%  (p=0.000 n=17+18)
CodeDecoder-12                    8.43ms ± 1%    8.32ms ± 1%   -1.35%  (p=0.000 n=18+20)
UnicodeDecoder-12                  399ns ± 0%     339ns ± 0%  -15.00%  (p=0.000 n=20+19)
DecoderStream-12                   281ns ± 1%     231ns ± 0%  -17.91%  (p=0.000 n=20+16)
CodeUnmarshal-12                  9.35ms ± 2%    9.15ms ± 2%   -2.11%  (p=0.000 n=20+20)
CodeUnmarshalReuse-12             8.41ms ± 2%    8.29ms ± 2%   -1.34%  (p=0.000 n=20+20)
UnmarshalString-12                81.2ns ± 2%    74.0ns ± 4%   -8.89%  (p=0.000 n=20+20)
UnmarshalFloat64-12               71.1ns ± 2%    64.3ns ± 1%   -9.60%  (p=0.000 n=20+19)
UnmarshalInt64-12                 60.6ns ± 2%    53.2ns ± 0%  -12.28%  (p=0.000 n=18+18)
Issue10335-12                     96.9ns ± 0%    87.7ns ± 1%   -9.52%  (p=0.000 n=17+20)
Unmapped-12                        247ns ± 4%     231ns ± 3%   -6.34%  (p=0.000 n=20+20)
TypeFieldsCache/MissTypes1-12     11.1µs ± 0%    11.1µs ± 0%     ~     (p=0.376 n=19+20)
TypeFieldsCache/MissTypes10-12    33.9µs ± 0%    33.8µs ± 0%   -0.32%  (p=0.000 n=18+9)

name                            old speed      new speed      delta
CodeEncoder-12                  1.03GB/s ± 1%  1.01GB/s ± 0%   -1.15%  (p=0.000 n=20+19)
CodeMarshal-12                   930MB/s ± 1%   915MB/s ± 0%   -1.60%  (p=0.000 n=17+18)
CodeDecoder-12                   230MB/s ± 1%   233MB/s ± 1%   +1.37%  (p=0.000 n=18+20)
UnicodeDecoder-12               35.0MB/s ± 0%  41.2MB/s ± 0%  +17.60%  (p=0.000 n=20+19)
CodeUnmarshal-12                 208MB/s ± 2%   212MB/s ± 2%   +2.16%  (p=0.000 n=20+20)

name                            old alloc/op   new alloc/op   delta
Issue10335-12                       184B ± 0%      184B ± 0%     ~     (all equal)
Unmapped-12                         216B ± 0%      216B ± 0%     ~     (all equal)

name                            old allocs/op  new allocs/op  delta
Issue10335-12                       3.00 ± 0%      3.00 ± 0%     ~     (all equal)
Unmapped-12                         4.00 ± 0%      4.00 ± 0%     ~     (all equal)

Change-Id: I4b1a87a205da2ef9a572f86f85bc833653c61570
Reviewed-on: https://go-review.googlesource.com/98440
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-03-03 17:16:47 +00:00
Pascal S. de Kloe
5d11838654 encoding/json: read ahead after value consumption
Eliminates the need for an extra scanner, read undo and some other tricks.

name                    old time/op    new time/op    delta
CodeEncoder-12            1.92ms ± 0%    1.91ms ± 1%   -0.65%  (p=0.000 n=17+20)
CodeMarshal-12            2.13ms ± 2%    2.12ms ± 1%   -0.49%  (p=0.038 n=18+17)
CodeDecoder-12            8.55ms ± 2%    8.49ms ± 1%     ~     (p=0.119 n=20+18)
UnicodeDecoder-12          411ns ± 0%     422ns ± 0%   +2.77%  (p=0.000 n=19+15)
DecoderStream-12           320ns ± 1%     307ns ± 1%   -3.80%  (p=0.000 n=18+20)
CodeUnmarshal-12          9.65ms ± 3%    9.58ms ± 3%     ~     (p=0.157 n=20+20)
CodeUnmarshalReuse-12     8.54ms ± 3%    8.56ms ± 2%     ~     (p=0.602 n=20+20)
UnmarshalString-12         110ns ± 1%      87ns ± 2%  -21.53%  (p=0.000 n=16+20)
UnmarshalFloat64-12        101ns ± 1%      77ns ± 2%  -23.08%  (p=0.000 n=19+20)
UnmarshalInt64-12         94.5ns ± 2%    68.4ns ± 1%  -27.60%  (p=0.000 n=20+20)
Issue10335-12              128ns ± 1%     100ns ± 1%  -21.89%  (p=0.000 n=19+18)
Unmapped-12                427ns ± 3%     247ns ± 4%  -42.17%  (p=0.000 n=20+20)
NumberIsValid-12          23.0ns ± 0%    21.7ns ± 0%   -5.73%  (p=0.000 n=20+20)
NumberIsValidRegexp-12     641ns ± 0%     642ns ± 0%   +0.15%  (p=0.003 n=19+19)
EncoderEncode-12          56.9ns ± 0%    55.0ns ± 1%   -3.32%  (p=0.012 n=2+17)

name                    old speed      new speed      delta
CodeEncoder-12          1.01GB/s ± 1%  1.02GB/s ± 1%   +0.71%  (p=0.000 n=18+20)
CodeMarshal-12           913MB/s ± 2%   917MB/s ± 1%   +0.49%  (p=0.038 n=18+17)
CodeDecoder-12           227MB/s ± 2%   229MB/s ± 1%     ~     (p=0.110 n=20+18)
UnicodeDecoder-12       34.1MB/s ± 0%  33.1MB/s ± 0%   -2.73%  (p=0.000 n=19+19)
CodeUnmarshal-12         201MB/s ± 3%   203MB/s ± 3%     ~     (p=0.151 n=20+20)

name                    old alloc/op   new alloc/op   delta
Issue10335-12               320B ± 0%      184B ± 0%  -42.50%  (p=0.000 n=20+20)
Unmapped-12                 568B ± 0%      216B ± 0%  -61.97%  (p=0.000 n=20+20)
EncoderEncode-12           0.00B          0.00B          ~     (all equal)

name                    old allocs/op  new allocs/op  delta
Issue10335-12               4.00 ± 0%      3.00 ± 0%  -25.00%  (p=0.000 n=20+20)
Unmapped-12                 18.0 ± 0%       4.0 ± 0%  -77.78%  (p=0.000 n=20+20)
EncoderEncode-12            0.00           0.00          ~     (all equal)

Fixes #17914
Updates #20693
Updates #10335

Change-Id: I0459a52febb8b79c9a2991e69ed2614cf8740429
Reviewed-on: https://go-review.googlesource.com/47152
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-03-01 19:03:04 +00:00
Joe Tsai
4338518da8 encoding/json: avoid assuming side-effect free reflect.Value.Addr().Elem()
Consider the following:
	type child struct{ Field string }
	type parent struct{ child }

	p := new(parent)
	v := reflect.ValueOf(p).Elem().Field(0)
	v.Field(0).SetString("hello")           // v.Field = "hello"
	v = v.Addr().Elem()                     // v = *(&v)
	v.Field(0).SetString("goodbye")         // v.Field = "goodbye"

It would appear that v.Addr().Elem() should have the same value, and
that it would be safe to set "goodbye".
However, after CL 66331, any interspersed calls between Field calls
causes the RO flag to be set.
Thus, setting to "goodbye" actually causes a panic.

That CL affects decodeState.indirect which assumes that back-to-back
Value.Addr().Elem() is side-effect free. We fix that logic to keep
track of the Addr() and Elem() calls and set v back to the original
after a full round-trip has occured.

Fixes #24152
Updates #24153

Change-Id: Ie50f8fe963f00cef8515d89d1d5cbc43b76d9f9c
Reviewed-on: https://go-review.googlesource.com/97796
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-03-01 00:16:20 +00:00
Joe Tsai
91a6a2a30f encoding/json: make error capture logic in recover more type safe
Rather than only ignoring runtime.Error panics, which are a very
narrow set of possible panic values, switch it such that the json
package only captures panic values that have been properly wrapped
in a jsonError struct. This ensures that only intentional panics
originating from the json package are captured.

Fixes #23012

Change-Id: I5e85200259edd2abb1b0512ce6cc288849151a6d
Reviewed-on: https://go-review.googlesource.com/94019
Run-TryBot: Joe Tsai <thebrokentoaster@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-02-14 21:34:26 +00:00
Joe Tsai
70f441bc49 encoding/json: error when trying to set an embedded pointer to unexported struct types
This CL reverts CL 76851 and takes a different approach to #21357.
The changes in encode.go and encode_test.go are reverts that
rolls back the changed behavior in CL 76851 where
embedded pointers to unexported struct types were
unilaterally ignored in both marshal and unmarshal.

Instead, these fields are handled as before with the exception that
it returns an error when Unmarshal is unable to set an unexported field.
The behavior of Marshal is now unchanged with regards to #21357.

This policy maintains the greatest degree of backwards compatibility
and avoids silently discarding data the user may have expected to be present.

Fixes #21357

Change-Id: I7dc753280c99f786ac51acf7e6c0246618c8b2b1
Reviewed-on: https://go-review.googlesource.com/82135
Run-TryBot: Joe Tsai <thebrokentoaster@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-12-06 19:27:26 +00:00
Michael Schurter
7eb7f8f5a7 encoding/json: reduce allocations by Decoder for \uXXXX
Manually convert hex escape sequence to rune instead of calling
strconv.ParseUint.

This inlines the unhex func from docs (and many other packages).

name              old time/op    new time/op    delta
UnicodeDecoder-4     468ns ± 1%     402ns ± 1%  -14.26%  (p=0.000
n=10+10)

name              old speed      new speed      delta
UnicodeDecoder-4  29.9MB/s ± 1%  34.8MB/s ± 1%  +16.59%  (p=0.000
n=10+10)

name              old alloc/op   new alloc/op   delta
UnicodeDecoder-4     44.0B ± 0%     36.0B ± 0%  -18.18%  (p=0.000
n=10+10)

name              old allocs/op  new allocs/op  delta
UnicodeDecoder-4      4.00 ± 0%      2.00 ± 0%  -50.00%  (p=0.000
n=10+10)

Fixes #20567

Change-Id: If350978d5bb98ff517485752184d02249f5d1f3a
Reviewed-on: https://go-review.googlesource.com/44738
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-11-22 03:36:29 +00:00
Ivan Bertona
2596a0c075 encoding/json: disallow unknown fields in Decoder
Add a DisallowUnknownFields flag to Decoder.

DisallowUnknownFields causes the Decoder to return an error when
the the decoding destination is a struct and the input contains
object keys which do not match any non-ignored, public field the
destination, including keys whose value is set to null.

Note: this fix has already been worked on in 27231, which seems
to be abandoned. This version is a slightly simpler implementation
and is up to date with the master branch.

Fixes #15314

Change-Id: I987a5857c52018df334f4d1a2360649c44a7175d
Reviewed-on: https://go-review.googlesource.com/74830
Reviewed-by: Joe Tsai <joetsai@google.com>
Run-TryBot: Joe Tsai <joetsai@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-10-31 22:28:36 +00:00
Joe Tsai
a3e013b082 encoding/json: use Deprecated markers
In #10909, it was decided that "Deprecated:" is a magic string for
tools (e.g., #17056 for godoc) to detect deprecated identifiers.
Use those convention instead of custom written prose.

Change-Id: Ia514fc3c88fc502e86c6e3de361c435f4cb80b22
Reviewed-on: https://go-review.googlesource.com/70110
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Joe Tsai <thebrokentoaster@gmail.com>
2017-10-11 22:09:22 +00:00
Daniel Martí
99da8730b0 all: remove some double spaces from comments
Went mainly for the ones that make no sense, such as the ones
mid-sentence or after commas.

Change-Id: Ie245d2c19cc7428a06295635cf6a9482ade25ff0
Reviewed-on: https://go-review.googlesource.com/57293
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-08-26 15:09:09 +00:00
Brad Fitzpatrick
912bb817b0 Revert "encoding/json: reduce unmarshal mallocs for unmapped fields"
This reverts commit df68afd07c (https://golang.org/cl/33276)

Reason for revert: made other benchmarks worse

Fixes #20693 (details)
Updates #17914
Updates #10335

Change-Id: If451b620803ccb0536b89c76c4353d2185d57d7e
Reviewed-on: https://go-review.googlesource.com/47211
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2017-06-29 17:21:51 +00:00
Alberto Donizetti
3cc2da6397 encoding/json: clarify unmarshaling behaviour on bad fields
Fixes #19526

Change-Id: Ifaaf454e0e89fdf4309118c2e2e6ac0d0a43c39d
Reviewed-on: https://go-review.googlesource.com/44711
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-06-05 16:32:35 +00:00
Pascal S. de Kloe
df68afd07c encoding/json: reduce unmarshal mallocs for unmapped fields
JSON decoding performs poorly for unmapped and ignored fields. We noticed better
performance when unmarshalling unused fields. The loss comes mostly from calls
to scanner.error as described at #17914.

benchmark                 old ns/op     new ns/op     delta
BenchmarkIssue10335-8     431           408           -5.34%
BenchmarkUnmapped-8       1744          1314          -24.66%

benchmark                 old allocs     new allocs     delta
BenchmarkIssue10335-8     4              3              -25.00%
BenchmarkUnmapped-8       18             4              -77.78%

benchmark                 old bytes     new bytes     delta
BenchmarkIssue10335-8     320           312           -2.50%
BenchmarkUnmapped-8       568           344           -39.44%

Fixes #17914, improves #10335

Change-Id: I7d4258a94eb287c0fe49e7334795209b90434cd0
Reviewed-on: https://go-review.googlesource.com/33276
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-03-20 23:58:56 +00:00
Tuo Shan
4fafc843a2 encoding/json: clarify documention for Unmarshal into a pointer.
Fixes #18730.

Change-Id: If3ef28e62f7e449d4c8dc1dfd78f7d6f5a87ed26
Reviewed-on: https://go-review.googlesource.com/36478
Reviewed-by: Russ Cox <rsc@golang.org>
2017-02-10 13:39:10 +00:00
Russ Cox
aeb8b9591c encoding/json: fix bad formatting introduced in CL 20356
Change-Id: I39a8b543e472e5ec5d4807a9b7f61657465c5ce5
Reviewed-on: https://go-review.googlesource.com/31816
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-10-24 20:37:52 +00:00
Russ Cox
f444b48fe4 encoding/json: fix decoding of null into Unmarshaler, TextUnmarshaler
1. Define behavior for Unmarshal of JSON null into Unmarshaler and
TextUnmarshaler. Specifically, an Unmarshaler will be given the
literal null and can decide what to do (because otherwise
json.RawMessage is impossible to implement), and a TextUnmarshaler
will be skipped over (because there is no text to unmarshal), like
most other inappropriate types. Document this in Unmarshal, with a
reminder in UnmarshalJSON about handling null.

2. Test all this.

3. Fix the TextUnmarshaler case, which was returning an unmarshalling
error, to match the definition.

4. Fix the error that had been used for the TextUnmarshaler, since it
was claiming that there was a JSON string when in fact the problem was
NOT having a string.

5. Adjust time.Time and big.Int's UnmarshalJSON to ignore null, as is
conventional.

Fixes #9037.

Change-Id: If78350414eb8dda712867dc8f4ca35a9db041b0c
Reviewed-on: https://go-review.googlesource.com/30944
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-10-17 15:21:33 +00:00
Russ Cox
0da30d5cbd encoding/json: handle misspelled JSON literals in ,string
Fixes #15146.

Change-Id: I229611b9cc995a1391681c492c4d742195c787ea
Reviewed-on: https://go-review.googlesource.com/30943
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-10-13 17:30:39 +00:00
Jirka Daněk
b9fd510cd0 encoding/json: add struct and field name to UnmarshalTypeError message
The UnmarshalTypeError has two new fields Struct and Field,
used when constructing the error message.

Fixes #6716.

Change-Id: I67da171480a9491960b3ae81893770644180f848
Reviewed-on: https://go-review.googlesource.com/18692
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-10-05 20:28:59 +00:00
Caleb Spare
f05c3aa24d encoding/json: support maps with integer keys
This change makes encoding and decoding support integer types in map
keys, converting to/from JSON string keys.

JSON object keys are still sorted lexically, even though the keys may be
integer strings.

For backwards-compatibility, the existing Text(Un)Marshaler support for
map keys (added in CL 20356) does not take precedence over the default
encoding for string types. There is no such concern for integer types,
so integer map key encoding is only used as a fallback if the map key
type is not a Text(Un)Marshaler.

Fixes #12529.

Change-Id: I7e68c34f9cd19704b1d233a9862da15fabf0908a
Reviewed-on: https://go-review.googlesource.com/22060
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-05-10 03:53:12 +00:00
Brad Fitzpatrick
462aa7ec7b encoding/json: update docs to not use misuse the term "object"
In JSON terminology, "object" is a collect of key/value pairs. But a
JSON object is only one type of JSON value (others are string, number,
array, true, false, null).

This updates the Go docs (at least the public godoc) to not use
"object" when we mean any JSON value.

Change-Id: Ieb1c456c703693714d63d9d09d306f4d9e8f4597
Reviewed-on: https://go-review.googlesource.com/22003
Reviewed-by: Andrew Gerrand <adg@golang.org>
2016-04-16 22:11:57 +00:00
Augusto Roman
ffbd31e9f7 encoding/json: allow non-string type keys for (un-)marshal
This CL allows JSON-encoding & -decoding maps whose keys are types that
implement encoding.TextMarshaler / TextUnmarshaler.

During encode, the map keys are marshaled upfront so that they can be
sorted.

Fixes #12146

Change-Id: I43809750a7ad82a3603662f095c7baf75fd172da
Reviewed-on: https://go-review.googlesource.com/20356
Run-TryBot: Caleb Spare <cespare@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-04-05 15:08:04 +00:00
Brad Fitzpatrick
5fea2ccc77 all: single space after period.
The tree's pretty inconsistent about single space vs double space
after a period in documentation. Make it consistently a single space,
per earlier decisions. This means contributors won't be confused by
misleading precedence.

This CL doesn't use go/doc to parse. It only addresses // comments.
It was generated with:

$ perl -i -npe 's,^(\s*// .+[a-z]\.)  +([A-Z]),$1 $2,' $(git grep -l -E '^\s*//(.+\.)  +([A-Z])')
$ go test go/doc -update

Change-Id: Iccdb99c37c797ef1f804a94b22ba5ee4b500c4f7
Reviewed-on: https://go-review.googlesource.com/20022
Reviewed-by: Rob Pike <r@golang.org>
Reviewed-by: Dave Day <djd@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-03-02 00:13:47 +00:00
Ian Lance Taylor
5755c011de encoding/json: doc: Decode only writes to exported fields
Fixes #13867.

Change-Id: I6c0a6c64369681840df60f63036c2eece27de8b8
Reviewed-on: https://go-review.googlesource.com/18394
Reviewed-by: Russ Cox <rsc@golang.org>
2016-01-08 16:15:25 +00:00
Russ Cox
c4135dac63 encoding/json: streamline, unexport valid Number checking
Followup to CL 12250.

For #10281.

Change-Id: If25d9cac92f10327bb355f2d11b00c625b464661
Reviewed-on: https://go-review.googlesource.com/17199
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-12-04 16:18:57 +00:00
Russ Cox
3e6529d202 encoding/json: revise docs for Unmarshal into map, slice, array
Fixes #12972.

Change-Id: Id0611667e6149753c351c0c5e01211340a87d3fd
Reviewed-on: https://go-review.googlesource.com/17230
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2015-12-03 14:54:24 +00:00
Erik Dubbelboer
c4be790c0e encoding/json: check if Number is valid
json.Number is a special case which didn't have any checks and could result in invalid JSON.

Fixes #10281

Change-Id: Ie3e726e4d6bf6a6aba535d36f6107013ceac913a
Reviewed-on: https://go-review.googlesource.com/12250
Reviewed-by: Russ Cox <rsc@golang.org>
2015-11-25 16:18:36 +00:00
Håvard Haugen
c60707b14d encoding/json: use reflect.SetBytes when decoding bytes
This allows slices of custom types with byte as underlying type to be
decoded, fixing a regression introduced in CL 9371.

Fixes #12921.

Change-Id: I62a715eaeaaa912b6bc599e94f9981a9ba5cb242
Reviewed-on: https://go-review.googlesource.com/16303
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2015-11-14 23:41:46 +00:00
Andrew Gerrand
143f3fd0ee encoding/json: spell "marshaling" and "unmarshaling" consistently
Fixes #12431

Change-Id: I67c42bf2cd9285f471387248fd9c22a16b158349
Reviewed-on: https://go-review.googlesource.com/14150
Reviewed-by: Dmitri Shuralyov <shurcool@gmail.com>
Reviewed-by: Rob Pike <r@golang.org>
2015-09-23 00:48:35 +00:00
Marvin Stenger
fcf8143d63 encoding/json: scanner: use byte, more consistent
The fields step and redoState of struct scanner are now defined as
`func(s *scanner, c byte) int` instead of
`func(s *scanner, c int) int`, since bytes are sufficient.
Further changes improve the consistency in the scanner.go file.

Change-Id: Ifb85f2130d728d2b936d79914d87a1f0b5c6ee7d
Reviewed-on: https://go-review.googlesource.com/14801
Reviewed-by: Andrew Gerrand <adg@golang.org>
Run-TryBot: Andrew Gerrand <adg@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2015-09-21 01:55:52 +00:00
Russ Cox
80e6d638bf encoding/json: revert "fix decoding of JSON null values"
Fixes #11912.
Fixes #11937.

This reverts commit 1a99ba55df.

Change-Id: I32b76053fdabc59f28ca5bedf1b15c0baa8afae1
Reviewed-on: https://go-review.googlesource.com/12893
Reviewed-by: Didier Spezia <didier.06@gmail.com>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2015-07-30 20:00:56 +00:00
Didier Spezia
1a99ba55df encoding/json: fix decoding of JSON null values
JSON decoding currently fails for null values bound to any type
which does implement the JSON Unmarshaler interface without checking
for null values (such as time.Time).

It also fails for types implementing the TextUnmarshaler interface.

The expected behavior of the JSON decoding engine in such case is
to process null by keeping the value unchanged without producing
any error.

Make sure null values are handled by the decoding engine itself,
and never passed to the UnmarshalText or UnmarshalJSON methods.

Fixes #9037

Change-Id: I261d85587ba543ef6f1815555b2af9311034d5bb
Reviewed-on: https://go-review.googlesource.com/9376
Reviewed-by: Russ Cox <rsc@golang.org>
2015-07-22 15:39:54 +00:00
Russ Cox
749b391c55 encoding/json: document and test overwrite of slice, map during Unmarshal
Fixes #8837.

Change-Id: Iaaecbb0b324004cb74b16b764126b01315e6a16e
Reviewed-on: https://go-review.googlesource.com/12209
Reviewed-by: Andrew Gerrand <adg@golang.org>
2015-07-15 05:51:02 +00:00