dart-lang/source_gen v0.5.9 on GitHub

0.5.9

Update the minimum Dart SDK to 1.22.1.
Deprecated builder.dart: import source_gen.dart instead.

Added TypeChecker, a high-level API for performing static type checks:

import 'package:analyzer/dart/element/type.dart';
import 'package:source_gen/source_gen.dart';

void checkType(DartType dartType) {
  // Checks compared to runtime type `SomeClass`.
  print(const TypeChecker.forRuntime(SomeClass).isExactlyType(dartType));
  
  // Checks compared to a known Url/Symbol:
  const TypeChecker.forUrl('package:foo/foo.dart#SomeClass');
  
  // Checks compared to another resolved `DartType`:
  const TypeChecker.forStatic(anotherDartType);
}

Failing to add a library directive to a library that is being used as a
generator target that generates partial files (part of) is now an explicit
error that gives a hint on how to name and fix your library:
```
> Could not find library identifier so a "part of" cannot be built.
>
> Consider adding the following to your source file:
>
> "library foo.bar;"
```
In Dart SDK >=1.25.0 this can be relaxed as part of can refer to a path.
To opt-in, GeneratorBuilder now has a new flag, requireLibraryDirective.
Set it to false, and also set your sdk constraint appropriately:
```
  sdk: '>=1.25.0 <2.0.0'
```
Added LibraryReader, a utility class for LibraryElement that exposes
high-level APIs, including findType, which traverses export directives
for publicly exported types. For example, to find Generator from
package:source_gen/source_gen.dart:
```
void example(LibraryElement pkgSourceGen) {
  var library = new LibraryReader(pkgSourceGen);

  // Instead of pkgSourceGen.getType('Generator'), which is null.
  library.findType('Generator');
}
```

Added ConstantReader, a high-level API for reading from constant (static)
values from Dart source code (usually represented by DartObject from the
analyzer package):

abstract class ConstantReader {
  factory ConstantReader(DartObject object) => ...

  // Other methods and properties also exist.

  /// Reads[ field] from the constant as another constant value.
  ConstantReader read(String field);

  /// Reads [field] from the constant as a boolean.
  ///
  /// If the resulting value is `null`, uses [defaultTo] if defined.
  bool readBool(String field, {bool defaultTo()});

  /// Reads [field] from the constant as an int.
  ///
  /// If the resulting value is `null`, uses [defaultTo] if defined.
  int readInt(String field, {int defaultTo()});

  /// Reads [field] from the constant as a string.
  ///
  /// If the resulting value is `null`, uses [defaultTo] if defined.
  String readString(String field, {String defaultTo()});
}