Under strict mode, the language service fails to typecheck nullable
symbols that have already been verified to be non-null.
This generates incorrect (false positive) and confusing diagnostics
for users.
To work around this issue in the short term, this commit changes the
diagnostic message from an error to a suggestion, and prompts users to
use the safe navigation operator (?) or non-null assertion operator (!).
For example, instead of
```typescript
{{ optional && optional.toString() }}
```
the following is cleaner:
```typescript
{{ optional?.toString() }}
{{ optional!.toString() }}
```
Note that with this change, users who legitimately make a typo in their
code will no longer see an error. I think this is acceptable, since
false positive is worse than false negative. However, if users follow
the suggestion, add ? or ! to their code, then the error will be surfaced.
This seems a reasonable trade-off.
References:
1. Safe navigation operator (?)
https://angular.io/guide/template-syntax#the-safe-navigation-operator----and-null-property-paths
2. Non-null assertion operator (!)
https://angular.io/guide/template-syntax#the-non-null-assertion-operator---
PR closes https://github.com/angular/angular/pull/35070
PR closes https://github.com/angular/vscode-ng-language-service/issues/589
PR Close#35200
This commit elaborates diagnostics produced for invalid template
contexts by including the name of the embedded template type using the
template context, and in the common case that the implicity property is
being referenced (e.g. in a `for .. of ..` expression), suggesting to
refine the type of the context. This suggestion is provided because
users will sometimes use a base class as the type of the context in the
embedded view, and a more specific context later on (e.g. in an
`ngOnChanges` method).
Closes https://github.com/angular/vscode-ng-language-service/issues/251
PR Close#34751
This commit adds a regression test to check that the language service
recognizes inputs and outputs declared in a directive decorator.
See #34874.
PR Close#34875
This commit removes some test scenarios from `parsing-cases.ts` and
colocate them with the test code instead. This makes the tests easier to
read and understand.
PR Close#34716
This commit fixes a bug in which we do testing for completions.
Subsequently, this exposes another bug in our implementation whereby
suggestions are not provided in "ngFor" where there should have been.
Currently, multiple test cases are grouped together in a single
template. This requires the template to be somewhat complete so that
test cases that depend on variables declared earlier would pass.
Consider the following example:
```
template: `
<div *ngFor="let ~{for-person}person of ~{for-people}people">
<span>Name: {{~{for-interp-person}person.~{for-interp-name}name}}</span>
<span>Age: {{person.~{for-interp-age}age}}</span>
</div>`,
```
In order to test `~{for-interp-person}`, `people` has to be included after
`~{for-people}`. This means the test case for `~{for-people}` is not
reflective of the actual use case because the variable is already there!
In real case, the expression would be incomplete, and our implementation
failed to take that into account.
This commit breaks such test into individual tests, and fix the bugs in
the underlying implementation.
PR Close#34473
`let` and `of` should be considered reserved keywords in template syntax
and thus should not be part of the autocomplete suggestions.
For reference, TypeScript does not provide such completions.
This commit removes these results and cleans up the code.
PR Close#34434
Previously, indexing a container type would not return completions for
the indexed type because for every TypeScript type, the recorded index
type was always marked as `undefined`, regardless of the index
signature.
This PR now returns the index type of TypeScript containers with numeric
or string index signatures. This allows use to generate completions for
arrays and defined index types:
```typescript
interface Container<T> {
[key: string]: T;
}
const ctr: Container<T>;
ctr['stringKey']. // gives `T.` completions
const arr: T[];
arr[0]. // gives `T.` completions
```
Note that this does _not_ provide completions for properties indexed by
string literals, e.g.
```typescript
interface Container<T> {
foo: T;
}
const ctr: Container<T>;
ctr['foo']. // does not give `T.` completions
```
Closes angular/vscode-ng-language-service#110
Closes angular/vscode-ng-language-service#277
PR Close#33775
There are many specs in `ts_plugin_spec.ts` that exercise the behavior
of completions. These specs should belong in `completions_spec` instead.
In addition,
1. Tests for `getExternalFiles()` added in `ts_plugin_spec.ts`
2. Fixed bug in MockHost.reset() to remove overriden script names
3. Add test for TS diagnostics when `angularOnly = true` is not set
PR Close#33159
This PR adds es2015 lib to the `tsconfig.json` of the test project so
that `Promise` could be used. Note this only affects diagnostics in the
IDE. The tsconfig in Language Service Mock Host is the actual config
values used, and it already has es2015 lib.
- Other minor cleanup: Rename imports in `main.ts`.
- Add more cases to `parsing-cases.ts`, which are tested in later PRs
PR Close#33157
This is the last part in refactoring of the test project.
This PR turns on strict mode for typechecking and fixed tests that
fail under this mode.
PR Close#32783
Language service uses a canonical "Tour of Heroes" project to test
various features, but the files are all contained in test_data.ts which
is hard to read and often contains errors that are difficult to catch
without proper IDE syntax highlighting. The directory structure is also
not clear from first glance.
This PR refactors the test project into standalone files in the proper
format.
Next up:
[ ] Update the interface of MockTypeScript to only accept scriptNames.
[ ] Remove test_data.ts
PR Close#32653
Pusztai Tibor
Keen Yee Liau
ayazhafiz
Keen Yee Liau
ivanwonder