frontend-plugin-api: support predicate overrides

Allow plugin and extension overrides to replace or remove existing if predicates. This makes conditional plugin and extension behavior overrideable through both plugin overrides and module-installed extension overrides.

Signed-off-by: Patrik Oldsberg <poldsberg@gmail.com>
Made-with: Cursor

packages/frontend-plugin-api/src/wiring/createExtension.ts

@@ -549,13 +549,18 @@ export function createExtension<
         );
       }
 
+      let ifPredicate = options.if;
+      if ('if' in overrideOptions) {
+        ifPredicate = overrideOptions.if;
+      }
+
       return createExtension({
         kind: options.kind,
         name: options.name,
         attachTo: (overrideOptions.attachTo ??
           options.attachTo) as ExtensionDefinitionAttachTo,
         disabled: overrideOptions.disabled ?? options.disabled,
-        if: overrideOptions.if ?? options.if,
+        if: ifPredicate,
         inputs: bindInputs(
           {
             ...(options.inputs ?? {}),

packages/frontend-plugin-api/src/wiring/createFrontendPlugin.ts

@@ -116,6 +116,11 @@ export interface OverridableFrontendPlugin<
   withOverrides(options: {
     extensions?: Array<ExtensionDefinition>;
 
+    /**
+     * Overrides the shared condition that applies to all extensions in the plugin.
+     */
+    if?: FilterPredicate;
+
     /**
      * Overrides the display title of the plugin.
      */
@@ -329,6 +334,10 @@ export function createFrontendPlugin<
       return `Plugin{id=${pluginId}}`;
     },
     withOverrides(overrides) {
+      let ifPredicate = options.if;
+      if ('if' in overrides) {
+        ifPredicate = overrides.if;
+      }
       const overrideExtensions = overrides.extensions ?? [];
       const overriddenExtensionIds = new Set(
         overrideExtensions.map(
@@ -344,6 +353,7 @@ export function createFrontendPlugin<
       return createFrontendPlugin({
         ...options,
         pluginId,
+        if: ifPredicate,
         title: overrides.title ?? options.title,
         icon: overrides.icon ?? options.icon,
         extensions: [...nonOverriddenExtensions, ...overrideExtensions],