`NgCompiler` is the heart of ngtsc and can be used to analyze and compile
Angular programs in a variety of environments. Most of these integrations
rely on `NgProgram` and the creation of an `NgCompilerHost` in order to
create a `ts.Program` with the right shape for `NgCompiler`.
However, certain environments (such as the Angular Language Service) have
their own mechanisms for creating `ts.Program`s that don't make use of a
`ts.CompilerHost`. In such environments, an `NgCompilerHost` does not make
sense.
This commit breaks the dependency of `NgCompiler` on `NgCompilerHost` and
extracts the specific interface of the host on which `NgCompiler` depends
into a new interface, `NgCompilerAdapter`. This interface includes methods
from `ts.CompilerHost`, the `ExtendedTsCompilerHost`, as well as APIs from
`NgCompilerHost`.
A consumer such as the language service can implement this API without
needing to jump through hoops to create an `NgCompilerHost` implementation
that somehow wraps its specific environment.
PR Close#37118
The html parser already normalizes line endings (converting `\r\n` to `\n`)
for most text in templates but it was missing the expressions of ICU expansions.
In ViewEngine backticked literal strings, used to define inline templates,
were already normalized by the TypeScript parser.
In Ivy we are parsing the raw text of the source file directly so the line
endings need to be manually normalized.
This change ensures that inline templates have the line endings of ICU
expression normalized correctly, which matches the ViewEngine.
In ViewEngine external templates, defined in HTML files, the behavior was
different, since TypeScript was not normalizing the line endings.
Specifically, ICU expansion "expressions" are not being normalized.
This is a problem because it means that i18n message ids can be different on
different machines that are setup with different line ending handling,
or if the developer moves a template from inline to external or vice versa.
The goal is always to normalize line endings, whether inline or external.
But this would be a breaking change since it would change i18n message ids
that have been previously computed. Therefore this commit aligns the ivy
template parsing to have the same "buggy" behavior for external templates.
There is now a compiler option `i18nNormalizeLineEndingsInICUs`, which
if set to `true` will ensure the correct non-buggy behavior. For the time
being this option defaults to `false` to ensure backward compatibility while
allowing opt-in to the desired behavior. This option's default will be
flipped in a future breaking change release.
Further, when this option is set to `false`, any ICU expression tokens,
which have not been normalized, are added to the `ParseResult` from the
`HtmlParser.parse()` method. In the future, this collection of tokens could
be used to diagnose and encourage developers to migrate their i18n message
ids. See FW-2106.
Closes#36725
PR Close#36741
This commit splits the ngtsc `core` package's api entrypoint, which
previously was a single `api.ts` file, into an api/ directory with multiple
files. This is done to isolate the parts of the API definitions pertaining
to the public-facing `angularCompilerOptions` field in tsconfig.json into a
single file, which will enable a public API guard test to be added in a
future commit.
PR Close#35885
