A constructor function may have been "synthesized" by TypeScript during
JavaScript emit, in the case no user-defined constructor exists and e.g.
property initializers are used. Those initializers need to be emitted
into a constructor in JavaScript, so the TypeScript compiler generates a
synthetic constructor.
This commit adds identification of such constructors as ngcc needs to be
able to tell if a class did originally have a constructor in the
TypeScript source. When a class has a superclass, a synthesized
constructor must not be considered as a user-defined constructor as that
prevents a base factory call from being created by ngtsc, resulting in a
factory function that does not inject the dependencies of the superclass.
Hence, we identify a default synthesized super call in the constructor
body, according to the structure that TypeScript emits.
PR Close#27897
This refactoring moves code around between a few of the ngtsc subpackages,
with the goal of having a more logical package structure. Additional
interfaces are also introduced where they make sense.
The 'metadata' package formerly contained both the partial evaluator,
the TypeScriptReflectionHost as well as some other reflection functions,
and the Reference interface and various implementations. This package
was split into 3 parts.
The partial evaluator now has its own package 'partial_evaluator', and
exists behind an interface PartialEvaluator instead of a top-level
function. In the future this will be useful for reducing churn as the
partial evaluator becomes more complicated.
The TypeScriptReflectionHost and other miscellaneous functions have moved
into a new 'reflection' package. The former 'host' package which contained
the ReflectionHost interface and associated types was also merged into this
new 'reflection' package.
Finally, the Reference APIs were moved to the 'imports' package, which will
consolidate all import-related logic in ngtsc.
PR Close#27743
