Add typed sub-feature settings (duckduckgo#2462)

* Support a `settings` property on subfeatures.

This can be optionally typed, but will default to Record<string, string>

* Add typings for Autofill feature.

Includes an example of how we can now type subfeature settings, using

* Rename d.ts to .ts

* Add type for autofill javascriptConfig setting

* Prettier

Author: sammacbeth

schema/config.ts

@@ -4,6 +4,7 @@ import { CookieFeature } from './features/cookie';
 import { TrackerAllowlistFeature } from './features/tracker-allowlist';
 import { WebCompatFeature } from './features/webcompat';
 import { DuckPlayerFeature } from './features/duckplayer';
+import { AutofillFeature } from './features/autofill';
 
 export { WebCompatSettings } from './features/webcompat';
 export { DuckPlayerSettings } from './features/duckplayer';
@@ -25,6 +26,7 @@ export type ConfigV4<VersionType> = {
     features: Record<string, Feature<any, VersionType>> & {
         // These features have typed settings
         autoconsent: AutoconsentFeature<VersionType>;
+        autofill: AutofillFeature<VersionType>;
         cookie: CookieFeature<VersionType>;
         duckPlayer: DuckPlayerFeature<VersionType>;
         trackerAllowlist: TrackerAllowlistFeature<VersionType>;

schema/feature.ts

@@ -17,8 +17,9 @@ type FeatureMeta = {
     sampleExcludeRecords?: any;
 };
 
-type SubFeature<VersionType> = {
+export type SubFeature<VersionType, SettingsType = Record<string, string>> = {
     state: FeatureState;
+    settings?: SettingsType;
     rollout?: {
         steps: { percent: number }[];
     };
@@ -31,13 +32,17 @@ type SubFeature<VersionType> = {
     minSupportedVersion?: VersionType;
 };
 
-export type Feature<SettingsType, VersionType> = {
+export type Feature<
+    SettingsType,
+    VersionType,
+    SubFeatures extends Record<string, SubFeature<VersionType>> = Record<string, SubFeature<VersionType>>,
+> = {
     readme?: string;
     _meta?: FeatureMeta;
     state: FeatureState;
     exceptions: SiteException[];
     settings?: SettingsType;
-    features?: Record<string, SubFeature<VersionType>>;
+    features?: SubFeatures;
     hash: string;
     minSupportedVersion?: VersionType;
 };

schema/features/autofill.ts

@@ -0,0 +1,35 @@
+import { CSSInjectFeatureSettings, Feature, SubFeature } from '../feature';
+
+// Type of the feature `settings` object
+type SettingsType = undefined;
+
+type ButtonConfig = {
+    shouldAutotap: boolean;
+    path: string;
+    selectors: string[];
+    labelTexts: string[];
+};
+
+type ImportFromGooglePasswordManager = {
+    settingsButton: ButtonConfig;
+    exportButton: ButtonConfig;
+    signInButton: ButtonConfig;
+};
+
+// Any subfeatures that have typed `settings` should be defined here.
+// Subfeatures without settings (or just string:string mappings for settings) will be automatically validated.
+type SubFeatures<VersionType> = {
+    canImportFromGooglePasswordManager?: SubFeature<
+        VersionType,
+        {
+            launchUrl: string;
+            javascriptConfig: CSSInjectFeatureSettings<ImportFromGooglePasswordManager>;
+        }
+    >;
+};
+
+export type AutofillFeature<VersionType> = Feature<
+    SettingsType,
+    VersionType,
+    SubFeatures<VersionType> & Record<string, SubFeature<VersionType>>
+>;