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Alex Rickabaugh 1eba57eb00 fix(language-service): show suggestion when type inference is suboptimal (#41072)
The Ivy Language Service uses the compiler's template type-checking engine,
which honors the configuration in the user's tsconfig.json. We recommend
that users upgrade to `strictTemplates` mode in their projects to take
advantage of the best possible type inference, and thus to have the best
experience in Language Service.

If a project is not using `strictTemplates`, then the compiler will not
leverage certain type inference options it has. One case where this is very
noticeable is the inference of let- variables for structural directives that
provide a template context guard (such as NgFor). Without `strictTemplates`,
these guards will not be applied and such variables will be inferred as
'any', degrading the user experience within Language Service.

This is working as designed, since the Language Service _should_ reflect
types exactly as the compiler sees them. However, the View Engine Language
Service used its own type system that _would_ infer these types even when
the compiler did not. As a result, it's confusing to some users why the
Ivy Language Service has "worse" type inference.

To address this confusion, this commit implements a suggestion diagnostic
which is shown in the Language Service for variables which could have been
narrowed via a context guard, but the type checking configuration didn't
allow it. This should make the reason why variables receive the 'any' type
as well as the action needed to improve the typings much more obvious,
improving the Language Service experience.

Fixes angular/vscode-ng-language-service#1155
Closes #41042

PR Close #41072
2021-03-23 09:39:19 -07:00
.circleci ci: run localize tests on windows (#40952) 2021-02-24 14:27:07 -08:00
.devcontainer build: update the recommended `Dockerfile` for VSCode remote development (#34697) 2020-01-09 13:31:14 -08:00
.github build: update the lock closed sha to the latest sha (#41140) 2021-03-09 13:24:50 -08:00
.husky build: update to husky@5 (#39739) 2020-11-18 11:11:41 -08:00
.ng-dev build: remove commit message max line length limit (#41157) 2021-03-10 11:05:43 -08:00
.vscode build: use "outFiles" in .vscode/launch.json to speed up debugging sessions (#39848) 2020-12-17 11:23:13 -08:00
.yarn build: update to yarn v1.22.10 (#40562) 2021-01-26 10:52:27 -08:00
aio ci: check that there are no unused contributor images (#41290) 2021-03-23 09:38:43 -07:00
dev-infra fix(dev-infra): remove commit message wizard and builder (#41280) 2021-03-19 12:41:09 -07:00
docs docs: document `help wanted` and `good first issue` labels (#41195) 2021-03-15 10:31:29 -07:00
goldens fix(language-service): show suggestion when type inference is suboptimal (#41072) 2021-03-23 09:39:19 -07:00
integration refactor(compiler): use `ɵɵInjectorDeclaration` rather than `ɵɵInjectorDef` in compiled output (#41119) 2021-03-22 08:57:18 -07:00
modules fix(dev-infra): update build tooling for latest changes in rules_nodejs (#40710) 2021-02-09 10:48:43 -08:00
packages fix(language-service): show suggestion when type inference is suboptimal (#41072) 2021-03-23 09:39:19 -07:00
scripts ci: improve error message when payload size check fails (#41116) 2021-03-08 10:03:59 -08:00
third_party docs: update links to use HTTPS as protocol (#39718) 2020-11-20 12:52:16 -08:00
tools feat(core): support TypeScript 4.2 (#41158) 2021-03-17 09:10:25 -07:00
.bazelignore ci: add integration test for Angular Elemens with SSR (#40559) 2021-02-12 08:55:25 -08:00
.bazelrc build: update config flags for snapshot builds (#40095) 2020-12-15 13:36:56 -08:00
.bazelversion build: update .bazelversion (#40579) 2021-01-26 11:35:54 -08:00
.clang-format feat(tooling): Add a .clang-format for automated JavaScript formatting. 2015-04-02 08:44:34 -07:00
.editorconfig build: use https link to editorconfig.org in .editorconfig (#27664) 2018-12-18 09:30:09 -08:00
.gitattributes test: fix ts api guardian and public guard tests on windows (#30105) 2019-04-26 16:32:22 -07:00
.gitignore fix(dev-infra): add vim .swp files to gitignore (#40094) 2020-12-14 11:39:41 -08:00
.gitmessage fix(platform-webworker): remove platform-webworker and platform-webworker-dynamic (#38846) 2020-09-30 09:13:59 -04:00
.mailmap build: add a Git .mailmap with my new name (#19550) 2017-10-09 14:35:30 -07:00
.nvmrc build: migrate to node@12.14.1 (#34955) 2020-01-27 09:31:22 -08:00
.pullapprove.yml ci: remove Stephen from PullApprove config (#41224) 2021-03-16 11:00:33 -07:00
.yarnrc build: update to yarn v1.22.10 (#40562) 2021-01-26 10:52:27 -08:00
BUILD.bazel test(upgrade): run tests against AngularJS v1.8.x as well (#39972) 2020-12-07 09:40:49 -08:00
CHANGELOG.md release: cut the v12.0.0-next.5 release (#41249) 2021-03-17 11:41:56 -07:00
CODE_OF_CONDUCT.md docs: add Discord as an official communication channel (#39149) 2020-10-14 10:23:15 -07:00
CONTRIBUTING.md docs: add an exception for accepting contributions (#39611) 2020-11-24 08:40:22 -08:00
LICENSE docs: update the copyright notice date (#40707) 2021-02-16 10:04:23 -08:00
README.md docs: document `help wanted` and `good first issue` labels (#41195) 2021-03-15 10:31:29 -07:00
WORKSPACE build: update to rules_nodejs@3.2.1 (#40972) 2021-02-24 08:00:03 -08:00
browser-providers.conf.js ci: remove IE 9 and IE 10 from CI (#38931) 2020-09-25 14:31:10 -04:00
gulpfile.js build: remove check-env script (#39980) 2020-12-07 09:48:11 -08:00
karma-js.conf.js test(core): tag `render3` test targets as ivy-only (#40127) 2021-01-06 08:28:03 -08:00
package.json fix(dev-infra): remove commit message wizard and builder (#41280) 2021-03-19 12:41:09 -07:00
test-events.js build: update license headers to reference Google LLC (#37205) 2020-05-26 14:26:58 -04:00
test-main.js feat(platform-server): allow shimming the global env sooner (#40559) 2021-02-12 08:55:25 -08:00
tslint.json build: exclude build-worker file from formatting (#40012) 2020-12-08 12:06:53 -08:00
yarn.lock fix(dev-infra): remove commit message wizard and builder (#41280) 2021-03-19 12:41:09 -07:00
yarn.lock.readme.md build: remove travisci leftovers (#27979) 2019-01-09 10:41:16 -08:00

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