Pete Bacon Darwin 58cdc22791 fix(ngcc): handle UMD factories that do not use all params (#34660)
In some cases, where a module imports a dependency
but does not actually use it, UMD bundlers may remove
the dependency parameter from the UMD factory function
definition.

For example:

```
import * as x from 'x';
import * as z from 'z';
export const y = x;
```

may result in a UMD bundle including:

```
(function (global, factory) {
    typeof exports === 'object' && typeof module !== 'undefined' ?
        factory(exports, require('x'), require('z')) :
    typeof define === 'function' && define.amd ?
        define(['exports', 'x', 'z'], factory) :
    (global = global || self, factory(global.myBundle = {}, global.x));
}(this, (function (exports, x) { 'use strict';
...
})));
```

Note that while the `z` dependency is provide in the call,
the factory itself only accepts `exports` and `x` as parameters.

Previously ngcc appended new dependencies to the end of the factory
function, but this breaks in the above scenario. Now the new
dependencies are prefixed at the front of parameters/arguments
already in place.

Fixes #34653

PR Close #34660
2020-01-08 15:07:36 -08:00
..

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