code review 103480043: fmt: fix signs when zero padding.

fmt: fix signs when zero padding.
Bug was introduced recently. Add more tests, fix the bugs.
Suppress + sign when not required in zero padding.
Do not zero pad infinities.
All old tests still pass.
This time for sure!
Fixes issue 8217.

[r, 2014-06-16 18:07:49]

Hello golang-codereviews@googlegroups.com,

I'd like you to review this change to
https://code.google.com/p/go

[kortschak, 2014-06-16 23:56:08]

https://codereview.appspot.com/103480043/diff/1/src/pkg/fmt/fmt_test.go
File src/pkg/fmt/fmt_test.go (right):

https://codereview.appspot.com/103480043/diff/1/src/pkg/fmt/fmt_test.go#newco...
src/pkg/fmt/fmt_test.go:529: {"% 020f", math.Inf(1), "                 Inf"},
Pin down complex as well? This works

{"%07.2f", 1 + 2i, "(0001.00+0002.00i)"},
{"%07.2f", 1 - 2i, "(0001.00-0002.00i)"},

The following would fail though? Is that working as intended?

{"%07.2f", -1 + 2i, "(-001.00+0002.00i)"},
{"%07.2f", -1 - 2i, "(-001.00-0002.00i)"},

[r, 2014-06-17 18:21:54]

Hello golang-codereviews@googlegroups.com, dan.kortschak@adelaide.edu.au (cc:
golang-codereviews@googlegroups.com),

Please take another look.

[rsc, 2014-06-17 21:50:30]

https://codereview.appspot.com/103480043/diff/20001/src/pkg/fmt/fmt_test.go
File src/pkg/fmt/fmt_test.go (right):

https://codereview.appspot.com/103480043/diff/20001/src/pkg/fmt/fmt_test.go#n...
src/pkg/fmt/fmt_test.go:679: var signs = []float64{1, -1}
1, -1, 0

https://codereview.appspot.com/103480043/diff/20001/src/pkg/fmt/fmt_test.go#n...
src/pkg/fmt/fmt_test.go:709: t.Fatal(f, one, two)
Error?
also maybe print the usual have, want message

[rsc, 2014-06-17 21:50:39]

LGTM once test changes pass

[r, 2014-06-17 21:55:55]

*** Submitted as https://code.google.com/p/go/source/detail?r=777dd5a434db ***

fmt: fix signs when zero padding.
Bug was introduced recently. Add more tests, fix the bugs.
Suppress + sign when not required in zero padding.
Do not zero pad infinities.
All old tests still pass.
This time for sure!
Fixes issue 8217.

LGTM=rsc
R=golang-codereviews, dan.kortschak, rsc
CC=golang-codereviews
https://codereview.appspot.com/103480043

[jscrockett01, 2014-06-18 14:19:27]

I know this change has already gone in, my comment is simply for going forward.

https://codereview.appspot.com/103480043/diff/40001/src/pkg/fmt/fmt_test.go
File src/pkg/fmt/fmt_test.go (right):

https://codereview.appspot.com/103480043/diff/40001/src/pkg/fmt/fmt_test.go#n...
src/pkg/fmt/fmt_test.go:679: var signs = []float64{1, 0, -1}
Can we test Inf as well, since that's been a sore spot?

var signs = []float64{1, 0, -1, math.Inf(+1),math.Inf(-1)}