New use cases for Factory Constructor

[stupendoussuperpowers]

Attempt to resolve #2202

[kwalrath]

Nice work, @stupendoussuperpowers! I'm going to let @rkj do the technical review of the text, since they filed the original bug. Once that's done, I can help you get the build working and maybe tweak the text a bit.

[kwalrath]

@rkj says this looks great to him, so I'll aim to fix the build tomorrow.

[stupendoussuperpowers]

Let me know if there's anything I can help out with!

[kwalrath]

I think I fixed the issues with the example (please take a look at the diffs), but the build is still failing for some reason. The issue is in two files not edited in this PR (see below).

@theacodes do you have a theory as to why this PR is failing analysis when the main build is fine?

   error • The argument type 'int' can't be assigned to the parameter type 'String'. • lib/library_tour/core/collections.dart:5:14 • argument_type_not_assignable
  error • A value of type 'dynamic' can't be assigned to a variable of type 'Person'. • lib/library_tour/core/hash_code.dart:24:21 • invalid_assignment

[stupendoussuperpowers]

I checked out the diffs, kind of embarassed about that mistake in the code.

As far as the files are concerned, not sure how useful my little detective work is but:

This is the code for the file /hash_code.dart, which has documentation which implies that we are supposed to ignore the invalid_assigment error that we saw above?

if (other is! Person) return false;  
// ignore: stable, dev, invalid_assignment, // https://github.com/dart-lang/sdk/issues/32236  
Person person = other;  

As far as the collections.dart is concerned, the error is pretty straightforward, we are storing an int in a List

Is there any chance that these errors popped up during the last build as well? And something changed in how these files are being loaded/deployed?

[theacodes]

Build is green now, just needed to update a string in an affected test.

Should be good to go now. The beta build is failing because of an unrelated analysis change, but I can send a follow-up PR to fix that.

[kwalrath]

Oops, I forgot to update that test. :(

[kwalrath]

Thank you, @theacodes! I was so mystified by the failure message that I missed the obvious.

@stupendoussuperpowers are you OK with my code and text changes? I've staged them:

https://kw-www-dartlang-1.firebaseapp.com/guides/language/language-tour#factory-constructors

[stupendoussuperpowers]

Yes, I went over the changes and I am fine with them

[theacodes]

No worries. It took me longer to find the error than it did to fix it. :)

…

On Wed, Aug 19, 2020 at 11:58 AM Kathy Walrath ***@***.***> wrote: Thank you, @theacodes <https://github.com/theacodes>! I was so mystified by the failure message that I missed the obvious. @stupendoussuperpowers <https://github.com/stupendoussuperpowers> are you OK with my code and text changes? I've staged them: https://kw-www-dartlang-1.firebaseapp.com/guides/language/language-tour#factory-constructors — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#2584 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAB5I4ZHHUI4LFFUJ2HS6S3SBPZARANCNFSM4QB7ZEJQ> .