Previously, several `ngtsc` and `ngcc` APIs dealing with class
declaration nodes used inconsistent types. For example, some methods of
the `DecoratorHandler` interface expected a `ts.Declaration` argument,
but actual `DecoratorHandler` implementations specified a stricter
`ts.ClassDeclaration` type.
As a result, the stricter methods would operate under the incorrect
assumption that their arguments were of type `ts.ClassDeclaration`,
while the actual arguments might be of different types (e.g. `ngcc`
would call them with `ts.FunctionDeclaration` or
`ts.VariableDeclaration` arguments, when compiling ES5 code).
Additionally, since we need those class declarations to be referenced in
other parts of the program, `ngtsc`/`ngcc` had to either repeatedly
check for `ts.isIdentifier(node.name)` or assume there was a `name`
identifier and use `node.name!`. While this assumption happens to be
true in the current implementation, working around type-checking is
error-prone (e.g. the assumption might stop being true in the future).
This commit fixes this by introducing a new type to be used for such
class declarations (`ts.Declaration & {name: ts.Identifier}`) and using
it consistently throughput the code.
PR Close #29209
Angular Compatibility Compiler (ngcc)
This compiler will convert node_modules compiled with ngc, into node_modules which
appear to have been compiled with ngtsc.
This conversion will allow such "legacy" packages to be used by the Ivy rendering engine.
Building
The project is built using Bazel:
yarn bazel build //packages/compiler-cli/ngcc
Unit Testing
The unit tests are built and run using Bazel:
yarn bazel test //packages/compiler-cli/ngcc/test
Integration Testing
There are tests that check the behavior of the overall executable:
yarn bazel test //packages/compiler-cli/ngcc/test:integration