[perf] Load localizations lazily

[msujew]

What it does

Related to #12924

Makes the localization entries used in the LocalizationProvider lazy. This is mainly relevant for localizations contributed by language packs, as they are usually split into dozens of files, which takes quite a while to load and parse. Each language pack takes roughly ~50-100ms to load. Having 10+ language packs installed can slow down startup time considerably.

How to test

1. Load a language pack and assert that it still works as expected.
2. Install all language packs (see here) and assert that the startup time isn't influenced (at least not noticably).

Follow-ups

Review checklist

• As an author, I have thoroughly tested my changes and carefully followed the review guidelines

Reminder for reviewers

• As a reviewer, I agree to behave in accordance with the review guidelines

[msujew]

cc @kittaakos This should help improve the startup performance in the Arduino IDE. I'd appreciate some feedback :)

[kittaakos]

I checked out the branch and made a quick comparison.

My changeset:

package.json:

diff --git a/package.json b/package.json
index 929fb05554..32b8de6e19 100644
--- a/package.json
+++ b/package.json
@@ -100,11 +100,23 @@
   ],
   "theiaPluginsDir": "plugins",
   "theiaPlugins": {
-    "eclipse-theia.builtin-extension-pack": "https://open-vsx.org/api/eclipse-theia/builtin-extension-pack/1.79.0/file/eclipse-theia.builtin-extension-pack-1.79.0.vsix",
-    "EditorConfig.EditorConfig": "https://open-vsx.org/api/EditorConfig/EditorConfig/0.16.6/file/EditorConfig.EditorConfig-0.16.6.vsix",
-    "dbaeumer.vscode-eslint": "https://open-vsx.org/api/dbaeumer/vscode-eslint/2.4.2/file/dbaeumer.vscode-eslint-2.4.2.vsix",
-    "ms-vscode.js-debug": "https://open-vsx.org/api/ms-vscode/js-debug/1.78.0/file/ms-vscode.js-debug-1.78.0.vsix",
-    "ms-vscode.js-debug-companion": "https://open-vsx.org/api/ms-vscode/js-debug-companion/1.1.2/file/ms-vscode.js-debug-companion-1.1.2.vsix"
+    "vscode-language-pack-bg": "https://open-vsx.org/api/MS-CEINTL/vscode-language-pack-bg/1.48.3/file/MS-CEINTL.vscode-language-pack-bg-1.48.3.vsix",
+    "vscode-language-pack-cs": "https://open-vsx.org/api/MS-CEINTL/vscode-language-pack-cs/1.78.0/file/MS-CEINTL.vscode-language-pack-cs-1.78.0.vsix",
+    "vscode-language-pack-de": "https://open-vsx.org/api/MS-CEINTL/vscode-language-pack-de/1.78.0/file/MS-CEINTL.vscode-language-pack-de-1.78.0.vsix",
+    "vscode-language-pack-es": "https://open-vsx.org/api/MS-CEINTL/vscode-language-pack-es/1.78.0/file/MS-CEINTL.vscode-language-pack-es-1.78.0.vsix",
+    "vscode-language-pack-fr": "https://open-vsx.org/api/MS-CEINTL/vscode-language-pack-fr/1.78.0/file/MS-CEINTL.vscode-language-pack-fr-1.78.0.vsix",
+    "vscode-language-pack-hu": "https://open-vsx.org/api/MS-CEINTL/vscode-language-pack-hu/1.48.3/file/MS-CEINTL.vscode-language-pack-hu-1.48.3.vsix",
+    "vscode-language-pack-it": "https://open-vsx.org/api/MS-CEINTL/vscode-language-pack-it/1.78.0/file/MS-CEINTL.vscode-language-pack-it-1.78.0.vsix",
+    "vscode-language-pack-ja": "https://open-vsx.org/api/MS-CEINTL/vscode-language-pack-ja/1.78.0/file/MS-CEINTL.vscode-language-pack-ja-1.78.0.vsix",
+    "vscode-language-pack-ko": "https://open-vsx.org/api/MS-CEINTL/vscode-language-pack-ko/1.78.0/file/MS-CEINTL.vscode-language-pack-ko-1.78.0.vsix",
+    "vscode-language-pack-nl": "https://open-vsx.org/api/MS-CEINTL/vscode-language-pack-nl/1.48.3/file/MS-CEINTL.vscode-language-pack-nl-1.48.3.vsix",
+    "vscode-language-pack-pl": "https://open-vsx.org/api/MS-CEINTL/vscode-language-pack-pl/1.78.0/file/MS-CEINTL.vscode-language-pack-pl-1.78.0.vsix",
+    "vscode-language-pack-pt-BR": "https://open-vsx.org/api/MS-CEINTL/vscode-language-pack-pt-BR/1.78.0/file/MS-CEINTL.vscode-language-pack-pt-BR-1.78.0.vsix",
+    "vscode-language-pack-ru": "https://open-vsx.org/api/MS-CEINTL/vscode-language-pack-ru/1.78.0/file/MS-CEINTL.vscode-language-pack-ru-1.78.0.vsix",
+    "vscode-language-pack-tr": "https://open-vsx.org/api/MS-CEINTL/vscode-language-pack-tr/1.78.0/file/MS-CEINTL.vscode-language-pack-tr-1.78.0.vsix",
+    "vscode-language-pack-uk": "https://open-vsx.org/api/MS-CEINTL/vscode-language-pack-uk/1.48.3/file/MS-CEINTL.vscode-language-pack-uk-1.48.3.vsix",
+    "vscode-language-pack-zh-hans": "https://open-vsx.org/api/MS-CEINTL/vscode-language-pack-zh-hans/1.78.0/file/MS-CEINTL.vscode-language-pack-zh-hans-1.78.0.vsix",
+    "vscode-language-pack-zh-hant": "https://open-vsx.org/api/MS-CEINTL/vscode-language-pack-zh-hant/1.78.0/file/MS-CEINTL.vscode-language-pack-zh-hant-1.78.0.vsix"
   },
   "theiaPluginsExcludeIds": [
     "ms-vscode.js-debug-companion",

.vscode/launch.json:

diff --git a/.vscode/launch.json b/.vscode/launch.json
index 00e3862ace..37276a42ef 100644
--- a/.vscode/launch.json
+++ b/.vscode/launch.json
@@ -30,7 +30,6 @@
         ".",
         "--log-level=debug",
         "--hostname=localhost",
-        "--no-cluster",
         "--app-project-path=${workspaceFolder}/examples/electron",
         "--remote-debugging-port=9222",
         "--no-app-auto-install",

HEAD (f038673) of the main branch:

theia_ide2_languages_cluster_mode_HEAD.mp4

From this PR:

theia_ide2_languages_cluster_mode_lazy.mp4

I did the profiling with the built-in profiler in VS Code on macOS 13.5.2, 2,6 GHz 6-Core Intel Core i7, 16 GB, starting the electron example app from the sources in cluster mode. Both profiles show the first second in the backend process.

From this PR, I can select and change the language. The app reloads as expected. Excellent work, Mark

[JonasHelming]

@planger FYI

[JonasHelming]

@msujew Do you want to trigger a re-review from @kittaakos ?

[msujew]

@JonasHelming I don't need a second review from @kittaakos, nothing has really changed. I just need an approval to merge this. Let me quickly rebase the PR :)