Change Effective Dart when "bad" code doesn't pass analysis

[kwalrath]

#2575 fixed the build, partly by removing test code that no longer passes analysis. Two occurrences were in Effective Dart:

• https://dart.dev/guides/language/effective-dart/design#do-annotate-when-dart-infers-the-wrong-type (diff)
• https://dart.dev/guides/language/effective-dart/usage#do-initialize-fields-at-their-declaration-when-possible (diff)

Can we produce valid "bad" code for both of these rules, or should we alter/delete the rule?

[johnpryan]

Just a drive-by comment, but in that first example, the good and bad snippets are exactly the same.

[kwalrath]

Just a drive-by comment, but in that first example, the good and bad snippets are exactly the same.

Looks like it's been that way since #889. What the heck?

[munificent]

Just a drive-by comment, but in that first example, the good and bad snippets are exactly the same.

Not exactly the same. In the good example, highest is declared using num and in the bad example, it's var.

For the second one, I think removing final from both the good and bad examples should fix it:

// Bad:
class Folder {
  final String name;
  List<Document> contents;

  Folder(this.name) : contents = [];
  Folder.temp() : name = 'temporary'; // Oops! Forgot contents.
}

// Good:
class Folder {
  final String name;
  List<Document> contents = [];

  Folder(this.name);
  Folder.temp() : name = 'temporary';
}

[kwalrath]

Just a drive-by comment, but in that first example, the good and bad snippets are exactly the same.

Not exactly the same. In the good example, highest is declared using num and in the bad example, it's var.

Oh wow, that's hard to see! I'm going to add a comment or highlight. It looks like the "bad" class is also missing from the bad snippet.

For the second one, I think removing final from both the good and bad examples should fix it

Cool, thanks!