Use a lockfile to persist Pub's installed version constellation.

Use a lockfile to persist Pub's installed version constellation.

Committed: https://code.google.com/p/dart/source/detail?r=9767

[Jennifer Messerly, 2012-07-19 18:45:34]

lgtm. Pub's tests are a thing of beauty!

https://chromiumcodereview.appspot.com/10796021/diff/2001/utils/pub/entrypoin...
File utils/pub/entrypoint.dart (right):

https://chromiumcodereview.appspot.com/10796021/diff/2001/utils/pub/entrypoin...
utils/pub/entrypoint.dart:84: return deleteDir(packageDir);
the idea here is to try and delete if if it already exists before creating the
symlink?

https://chromiumcodereview.appspot.com/10796021/diff/2001/utils/pub/git_sourc...
File utils/pub/git_source.dart (right):

https://chromiumcodereview.appspot.com/10796021/diff/2001/utils/pub/git_sourc...
utils/pub/git_source.dart:73: void validateDescription(description, [bool
fromLockFile=false]) {
nit: spaces around equals
http://www.dartlang.org/articles/style-guide/#do-use-a-space-around--in-named...

https://chromiumcodereview.appspot.com/10796021/diff/2001/utils/pub/version_s...
File utils/pub/version_solver.dart (right):

https://chromiumcodereview.appspot.com/10796021/diff/2001/utils/pub/version_s...
utils/pub/version_solver.dart:143: dep.source.descriptionsEqual(description,
lockedPackage.description)) {
long line

https://chromiumcodereview.appspot.com/10796021/diff/2001/utils/pub/version_s...
utils/pub/version_solver.dart:294: if
(solver.lockFile.packages.containsKey(name)) {
nit: I probably would write this as

  var lockedPackage = solver.lockFile.packages[name]
  if (lockedPackage != null) {
    var lockedVersion = lockedPackage.version;

saves a map lookup & slightly less characters :)

https://chromiumcodereview.appspot.com/10796021/diff/2001/utils/tests/pub/ver...
File utils/tests/pub/version_solver_test.dart (right):

https://chromiumcodereview.appspot.com/10796021/diff/2001/utils/tests/pub/ver...
utils/tests/pub/version_solver_test.dart:164: 'foo': '1.0.2',
so if the lockfile is incompatible, it just gets upgraded?

[nweiz, 2012-07-19 18:56:54]

https://chromiumcodereview.appspot.com/10796021/diff/2001/utils/pub/entrypoin...
File utils/pub/entrypoint.dart (right):

https://chromiumcodereview.appspot.com/10796021/diff/2001/utils/pub/entrypoin...
utils/pub/entrypoint.dart:84: return deleteDir(packageDir);
On 2012/07/19 18:45:34, John Messerly wrote:
> the idea here is to try and delete if if it already exists before creating the
> symlink?

That's right. We want to get rid of any already-installed packages in case we're
updating.

https://chromiumcodereview.appspot.com/10796021/diff/2001/utils/pub/git_sourc...
File utils/pub/git_source.dart (right):

https://chromiumcodereview.appspot.com/10796021/diff/2001/utils/pub/git_sourc...
utils/pub/git_source.dart:73: void validateDescription(description, [bool
fromLockFile=false]) {
On 2012/07/19 18:45:34, John Messerly wrote:
> nit: spaces around equals
>
http://www.dartlang.org/articles/style-guide/#do-use-a-space-around--in-named...

Done.

https://chromiumcodereview.appspot.com/10796021/diff/2001/utils/pub/version_s...
File utils/pub/version_solver.dart (right):

https://chromiumcodereview.appspot.com/10796021/diff/2001/utils/pub/version_s...
utils/pub/version_solver.dart:143: dep.source.descriptionsEqual(description,
lockedPackage.description)) {
On 2012/07/19 18:45:34, John Messerly wrote:
> long line

Done.

https://chromiumcodereview.appspot.com/10796021/diff/2001/utils/pub/version_s...
utils/pub/version_solver.dart:294: if
(solver.lockFile.packages.containsKey(name)) {
On 2012/07/19 18:45:34, John Messerly wrote:
> nit: I probably would write this as
> 
>   var lockedPackage = solver.lockFile.packages[name]
>   if (lockedPackage != null) {
>     var lockedVersion = lockedPackage.version;
> 
> saves a map lookup & slightly less characters :)

Done.

https://chromiumcodereview.appspot.com/10796021/diff/2001/utils/tests/pub/ver...
File utils/tests/pub/version_solver_test.dart (right):

https://chromiumcodereview.appspot.com/10796021/diff/2001/utils/tests/pub/ver...
utils/tests/pub/version_solver_test.dart:164: 'foo': '1.0.2',
On 2012/07/19 18:45:34, John Messerly wrote:
> so if the lockfile is incompatible, it just gets upgraded?

Yes. This should only happen when the user modifies the pubspec, which
presumably means they want updated versions of their files.

[Jennifer Messerly, 2012-07-19 19:06:30]

https://chromiumcodereview.appspot.com/10796021/diff/2001/utils/tests/pub/ver...
File utils/tests/pub/version_solver_test.dart (right):

https://chromiumcodereview.appspot.com/10796021/diff/2001/utils/tests/pub/ver...
utils/tests/pub/version_solver_test.dart:164: 'foo': '1.0.2',
On 2012/07/19 18:56:54, nweiz wrote:
> On 2012/07/19 18:45:34, John Messerly wrote:
> > so if the lockfile is incompatible, it just gets upgraded?
> 
> Yes. This should only happen when the user modifies the pubspec, which
> presumably means they want updated versions of their files.

Makes sense