In many testing scenarios, there is a common pattern:
1. Overwrite template (inline or external)
2. Find cursor position
3. Call one of language service APIs
4. Inspect spans in result
In order to faciliate this pattern, this commit refactors
`MockHost.overwrite()` and `MockHost.overwriteInlineTemplate()` to
allow a faux cursor symbol `¦` to be injected into the template, and
the methods will automatically remove it before updating the script snapshot.
Both methods will return the cursor position and the new text without
the cursor symbol.
This makes testing very convenient. Here's a typical example:
```ts
const {position, text} = mockHost.overwrite('template.html', `{{ ti¦tle }}`);
const quickInfo = ngLS.getQuickInfoAtPosition('template.html', position);
const {start, length} = quickInfo!.textSpan;
expect(text.substring(start, start + length)).toBe('title');
```
PR Close#38552
This commit adds a Compiler interface that wraps the actual ngtsc
compiler. The language-service specific compiler manages multiple
typecheck files using the Project interface, creating and adding
ScriptInfos as necessary.
This commit also adds `overrideInlineTemplate()` method to the mock
service so that we could test the Compiler diagnostics feature.
PR Close#36930
Add a mechanism to replace file contents for a specific file. This
allows us to write custom test scenarios in code without modifying the
test project.
Since we are no longer mocking the language service host, the file
overwrite needs to happen via the project service.
Project service manages a set of script infos, and overwriting the files
is a matter of updating the relevant script infos.
Note that the actual project service is wrapped inside a Mock Service.
Tests should not have direct access to the project service. All
manipulations should take place via the Mock Service.
The MockService provides a `reset()` method to undo temporary overwrites
after each test.
PR Close#36923
This commit adds a new mock host for testing the ivy language service.
Unlike the existing mock_host which mocks the LanguageServiceHost, the
Ivy mock host mocks just the filesystem interface, aka ts.ServerHost.
This is because Ivy language service requires an actual Project to
perform operations like adding synthetic typecheck files to the project,
and by extension, to the ts.Program. These requirements make the existing
mock host unsuitable to be reused.
This new testing structure also improves test performance, because the
old mock host copies (it actually creates symlinks, but still that's
relatively expensive due to the sheer number of files involved) all
@angular/* packages along with the typescript package to a temporary
node_modules directory. This is done every time setup() is called.
Instead, this new mock host just loads them from a pre-determined path
in Bazel runfiles.
PR Close#36879
Keen Yee Liau
Joey Perrott
Keen Yee Liau