delta/go-git.git/src/strconv, branch dev.typeparams

strconv: document parsing of leading +/-

2021-06-09T18:16:27+00:00

Explicitly document the handling of a sign prefix, and the interaction
between the sign and base prefixes.

Fixes #46641.

Change-Id: I3cd6773e3f074fe671a944a05a79d2408137fcd4
Reviewed-on: https://go-review.googlesource.com/c/go/+/325875
Trust: Damien Neil 
Run-TryBot: Damien Neil 
TryBot-Result: Go Bot 
Reviewed-by: Rob Pike

strconv: ParseFloat: always return ErrSyntax for bad syntax

2021-06-07T21:12:46+00:00

Previously we would sometimes return ErrRange if the parseable part of
the floating point number was out of range.

Fixes #46628

Change-Id: I15bbbb1e2a56fa27c19fe25ab5554d988cbfd9d2
Reviewed-on: https://go-review.googlesource.com/c/go/+/325750
Trust: Ian Lance Taylor 
Trust: Robert Griesemer 
Run-TryBot: Ian Lance Taylor 
TryBot-Result: Go Bot 
Reviewed-by: Robert Griesemer

strconv: fix a typo

2021-05-04T03:22:47+00:00

Change-Id: I17911dc95fb2126b41dc95f8839c4b3fa8f35d12
GitHub-Last-Rev: 88e120329301bd73db39e1081737a83f49a5672b
GitHub-Pull-Request: golang/go#45933
Reviewed-on: https://go-review.googlesource.com/c/go/+/316689
Reviewed-by: Robert Griesemer 
Reviewed-by: Ian Lance Taylor

strconv: add QuotedPrefix

2021-05-04T00:56:00+00:00

QuotedPrefix is similar to Unquote, but returns the quoted string verbatim
and ignores any data after the quoted string.

Fixes #45033

Change-Id: I9f69fe9e3e45cbe9e63581cf1b457facb625045d
Reviewed-on: https://go-review.googlesource.com/c/go/+/314775
Trust: Joe Tsai 
Reviewed-by: Ian Lance Taylor 
Run-TryBot: Ian Lance Taylor 
TryBot-Result: Go Bot

strconv: remove unused extfloat (Grisu3) ftoa code

2021-04-27T17:03:53+00:00

Change-Id: Ie8995362f9e8072b173d08820330d2d1e512aa71
Reviewed-on: https://go-review.googlesource.com/c/go/+/314029
Trust: Robert Griesemer 
Run-TryBot: Robert Griesemer 
TryBot-Result: Go Bot 
Reviewed-by: Robert Griesemer 
Reviewed-by: Emmanuel Odeke

strconv: Implement Ryū algorithm for ftoa shortest mode

2021-04-15T09:18:03+00:00

This patch implements the algorithm from Ulf Adams,
"Ryū: Fast Float-to-String Conversion" (doi:10.1145/3192366.3192369)
for formatting floating-point numbers with a fixed number of decimal
digits.

It is not a direct translation of the reference C implementation
but still follows the original paper. In particular, it uses full
128-bit powers of 10, which allows for more precision in the other
modes (fixed ftoa, atof).

name                              old time/op  new time/op   delta
AppendFloat/Decimal-4             49.6ns ± 3%   59.3ns ± 0%  +19.59%  (p=0.008 n=5+5)
AppendFloat/Float-4                122ns ± 1%     91ns ± 1%  -25.92%  (p=0.008 n=5+5)
AppendFloat/Exp-4                 89.3ns ± 1%  100.0ns ± 1%  +11.98%  (p=0.008 n=5+5)
AppendFloat/NegExp-4              88.3ns ± 2%   97.1ns ± 1%   +9.87%  (p=0.008 n=5+5)
AppendFloat/LongExp-4              143ns ± 2%    103ns ± 0%  -28.17%  (p=0.016 n=5+4)
AppendFloat/Big-4                  144ns ± 1%    110ns ± 1%  -23.26%  (p=0.008 n=5+5)
AppendFloat/BinaryExp-4           46.2ns ± 2%   46.0ns ± 1%     ~     (p=0.603 n=5+5)
AppendFloat/32Integer-4           49.1ns ± 1%   58.7ns ± 1%  +19.57%  (p=0.008 n=5+5)
AppendFloat/32ExactFraction-4     95.6ns ± 1%   88.6ns ± 1%   -7.30%  (p=0.008 n=5+5)
AppendFloat/32Point-4              122ns ± 1%     87ns ± 1%  -28.63%  (p=0.008 n=5+5)
AppendFloat/32Exp-4               88.6ns ± 2%   95.0ns ± 1%   +7.29%  (p=0.008 n=5+5)
AppendFloat/32NegExp-4            87.2ns ± 1%   91.3ns ± 1%   +4.63%  (p=0.008 n=5+5)
AppendFloat/32Shortest-4           107ns ± 1%     82ns ± 0%  -24.08%  (p=0.008 n=5+5)
AppendFloat/Slowpath64-4          1.00µs ± 1%   0.10µs ± 0%  -89.92%  (p=0.016 n=5+4)
AppendFloat/SlowpathDenormal64-4  34.1µs ± 3%    0.1µs ± 1%  -99.72%  (p=0.008 n=5+5)

Fixes #15672

Change-Id: Ib90dfa245f62490a6666671896013cf3f9a1fb22
Reviewed-on: https://go-review.googlesource.com/c/go/+/170080
Trust: Emmanuel Odeke 
Trust: Nigel Tao 
Run-TryBot: Emmanuel Odeke 
TryBot-Result: Go Bot 
Reviewed-by: Nigel Tao

strconv: implement Ryū-like algorithm for fixed precision ftoa

2021-04-15T08:44:21+00:00

This patch implements a simplified version of Ulf Adams,
"Ryū: Fast Float-to-String Conversion" (doi:10.1145/3192366.3192369)
for formatting floating-point numbers with a fixed number of decimal
digits.

It uses the same principles but does not need to handle
the complex task of finding a shortest representation.
This allows to handle a few more cases than Grisu3, notably
formatting with up to 18 significant digits.

name                         old time/op  new time/op  delta
AppendFloat/32Fixed8Hard-4   72.0ns ± 2%  56.0ns ± 2%  -22.28%  (p=0.000 n=10+10)
AppendFloat/32Fixed9Hard-4   74.8ns ± 0%  64.2ns ± 2%  -14.16%  (p=0.000 n=8+10)
AppendFloat/64Fixed1-4       60.4ns ± 1%  54.2ns ± 1%  -10.31%  (p=0.000 n=10+9)
AppendFloat/64Fixed2-4       66.3ns ± 1%  53.3ns ± 1%  -19.54%  (p=0.000 n=10+9)
AppendFloat/64Fixed3-4       61.0ns ± 1%  55.0ns ± 2%   -9.80%  (p=0.000 n=9+10)
AppendFloat/64Fixed4-4       66.9ns ± 0%  52.0ns ± 2%  -22.20%  (p=0.000 n=8+10)
AppendFloat/64Fixed12-4      95.5ns ± 1%  76.2ns ± 3%  -20.19%  (p=0.000 n=10+9)
AppendFloat/64Fixed16-4      1.62µs ± 0%  0.07µs ± 2%  -95.69%  (p=0.000 n=10+10)
AppendFloat/64Fixed12Hard-4  1.27µs ± 1%  0.07µs ± 1%  -94.83%  (p=0.000 n=9+9)
AppendFloat/64Fixed17Hard-4  3.68µs ± 1%  0.08µs ± 2%  -97.86%  (p=0.000 n=10+9)
AppendFloat/64Fixed18Hard-4  3.67µs ± 0%  3.72µs ± 1%   +1.44%  (p=0.000 n=9+10)

Updates #15672

Change-Id: I160963e141dd48287ad8cf57bcc3c686277788e8
Reviewed-on: https://go-review.googlesource.com/c/go/+/170079
Reviewed-by: Emmanuel Odeke 
Trust: Emmanuel Odeke 
Trust: Nigel Tao 
Trust: Robert Griesemer 
Run-TryBot: Emmanuel Odeke 
TryBot-Result: Go Bot

all: faster midpoint computation in binary search

2021-02-23T01:37:31+00:00

On my machine (3.1 GHz Quad-Core Intel Core i7, macOS 10.15.7 10.15.7), go 1.15.6

benchstat:
name          old time/op  new time/op  delta
SearchInts-8  20.3ns ± 1%  16.6ns ± 6%  -18.37%  (p=0.000 n=9+10)

Change-Id: I346e5955fd6df6ce10254b22267dbc8d5a2b16c0
Reviewed-on: https://go-review.googlesource.com/c/go/+/279439
Reviewed-by: Ben Shi 
Reviewed-by: Robert Griesemer 
Trust: Robert Griesemer

all: go fmt std cmd (but revert vendor)

2021-02-20T03:54:50+00:00

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
Trust: Russ Cox 
Run-TryBot: Russ Cox 
TryBot-Result: Go Bot 
Reviewed-by: Jason A. Donenfeld 
Reviewed-by: Ian Lance Taylor

Merge branch 'master' into dev.regabi

2020-12-14T16:42:42+00:00

Change-Id: I098acdbc5e2676aeb8700d935e796a9c29d04b88