Fixed parameters losing their original order

Fixed parameters losing their original order

BUG=
R=jmesserly@google.com

Committed: https://code.google.com/p/dart/source/detail?r=26301

[Tate Mandel, 2013-08-16 21:38:57]

This function takes a map and writes its contents out to a files in YAML format.


We were initially sorting they keys of the map to make sure that the YAML was
consistent, but it messed up the order of parameters in the output. I removed
the sorting and added a TODO to possibly address the fact that keys may not be
deterministic.

Thanks for taking a look.

[Jennifer Messerly, 2013-08-16 21:43:32]

lgtm

https://codereview.chromium.org/22877022/diff/1/pkg/docgen/lib/dart2yaml.dart
File pkg/docgen/lib/dart2yaml.dart (right):

https://codereview.chromium.org/22877022/diff/1/pkg/docgen/lib/dart2yaml.dart...
pkg/docgen/lib/dart2yaml.dart:32: // order is deterministic or something
similar.
maybe check that documentData is LinkedHashMap or SplayTreeMap? Those two are
ordered consistently.

[Tate Mandel, 2013-08-16 21:53:41]

I added the check, but had a question.

https://codereview.chromium.org/22877022/diff/1/pkg/docgen/lib/dart2yaml.dart
File pkg/docgen/lib/dart2yaml.dart (right):

https://codereview.chromium.org/22877022/diff/1/pkg/docgen/lib/dart2yaml.dart...
pkg/docgen/lib/dart2yaml.dart:32: // order is deterministic or something
similar.
On 2013/08/16 21:43:32, John Messerly wrote:
> maybe check that documentData is LinkedHashMap or SplayTreeMap? Those two are
> ordered consistently.

Are these the only two that are ordered consistently?

[Jennifer Messerly, 2013-08-16 22:05:49]

https://codereview.chromium.org/22877022/diff/1/pkg/docgen/lib/dart2yaml.dart
File pkg/docgen/lib/dart2yaml.dart (right):

https://codereview.chromium.org/22877022/diff/1/pkg/docgen/lib/dart2yaml.dart...
pkg/docgen/lib/dart2yaml.dart:32: // order is deterministic or something
similar.
On 2013/08/16 21:53:41, Tate Mandel wrote:
> On 2013/08/16 21:43:32, John Messerly wrote:
> > maybe check that documentData is LinkedHashMap or SplayTreeMap? Those two
are
> > ordered consistently.
> 
> Are these the only two that are ordered consistently?

hmm, it's tricky. I guess it depends on who calls this function and what data
they supply, and if the order contract should be enforced here or at a higher
level in the code :)

Map by itself doesn't say anything about order. LinkedHashMap and SplayTreeMap
both guarantee an order, and plain HashMap does not, but with a custom type that
implements Map there's really no way to tell for sure.

[Tate Mandel, 2013-08-16 22:09:45]

https://codereview.chromium.org/22877022/diff/1/pkg/docgen/lib/dart2yaml.dart
File pkg/docgen/lib/dart2yaml.dart (right):

https://codereview.chromium.org/22877022/diff/1/pkg/docgen/lib/dart2yaml.dart...
pkg/docgen/lib/dart2yaml.dart:32: // order is deterministic or something
similar.
On 2013/08/16 22:05:49, John Messerly wrote:
> On 2013/08/16 21:53:41, Tate Mandel wrote:
> > On 2013/08/16 21:43:32, John Messerly wrote:
> > > maybe check that documentData is LinkedHashMap or SplayTreeMap? Those two
> are
> > > ordered consistently.
> > 
> > Are these the only two that are ordered consistently?
> 
> hmm, it's tricky. I guess it depends on who calls this function and what data
> they supply, and if the order contract should be enforced here or at a higher
> level in the code :)
> 
> Map by itself doesn't say anything about order. LinkedHashMap and SplayTreeMap
> both guarantee an order, and plain HashMap does not, but with a custom type
that
> implements Map there's really no way to tell for sure.

I'd say it should be enforced elsewhere. We probably want to allow for the user
to decide how ordering should work. I updated the comment and reverted to the
initial version.

[Tate Mandel, 2013-08-16 23:13:38]

Committed patchset #3 manually as r26301 (presubmit successful).