fix: handle select attribute when changing to corpus without it

Fixes #490

Author: arildm

CHANGELOG.md

@@ -14,6 +14,7 @@
 
 ### Fixed
 
+- Error when switching corpus after searching by a corpus-specific attribute [#490](https://github.com/spraakbanken/korp-frontend/issues/490)
 - Error when downloading example KWIC [#491](https://github.com/spraakbanken/korp-frontend/issues/491)
 
 ## [9.11.4] – 2025-09-29

app/scripts/components/search/extended/cqp-value.ts

@@ -58,14 +58,15 @@ angular.module("korpApp").component("extendedCqpValue", {
                 const write = (val: string) => (shouldUseRegexp() ? val : regescape(val))
                 const read = (val: string) => (shouldUseRegexp() ? val : unregescape(val))
                 // Set initial input value
-                childScope.input = read(childScope.model as string)
+                childScope.input = read((childScope.model as string) || "")
                 // Sync from input to model, escaping special characters if needed
-                childScope.$watch("input", () => (childScope.model = write(childScope.input)))
-                childScope.$watch("orObj.op", () => (childScope.model = write(childScope.input)))
+                childScope.$watch("input", () => (childScope.model = write(childScope.input || "")))
+                childScope.$watch("orObj.op", () => (childScope.model = write(childScope.input || "")))
 
                 const locals = { $scope: childScope }
                 const { template, controller } = getWidget()
 
+                // TODO Are we always creating a new component instance here? What happens to the old ones?
                 // @ts-ignore
                 $controller(controller, locals)
                 const tmplElem = $compile(template)(childScope)

app/scripts/components/search/extended/widgets/common.ts

@@ -5,6 +5,7 @@ import { Condition } from "@/cqp_parser/cqp.types"
 import { StoreService } from "@/services/store"
 import { AttributeOption } from "@/corpora/corpus-set"
 import { loadOptions } from "@/search/extended-search"
+import { isEqual } from "lodash"
 
 export type Widget = {
     template: string
@@ -38,9 +39,9 @@ export const selectController = (autocomplete: boolean): IController => [
     "$scope",
     "store",
     function ($scope: SelectWidgetScope, store: StoreService) {
-        store.watch("corpus", (selected) => {
+        store.watch("corpus", (selected, old) => {
             // TODO Destroy if new corpus selection doesn't support the attribute?
-            if (selected.length > 0) {
+            if (selected.length > 0 && !isEqual(selected, old)) {
                 reloadValues()
             }
         })
@@ -53,7 +54,7 @@ export const selectController = (autocomplete: boolean): IController => [
                 $scope.loading = false
                 $scope.options = options
                 // Reset old selection if that option has been removed.
-                if (!autocomplete && !currentInputExists) {
+                if (!autocomplete && !currentInputExists && $scope.options.length) {
                     $scope.input = $scope.options[0][0]
                 }
             })

app/scripts/search/extended-search.ts

@@ -5,7 +5,7 @@ import { AttributeOption } from "@/corpora/corpus-set"
 import { loc, locAttribute } from "@/i18n"
 
 /** Load attribute values from backend data as selector options. */
-export async function loadOptions(attr: AttributeOption, lang: string) {
+export async function loadOptions(attr: AttributeOption, lang: string): Promise<string[][]> {
     const name = attr.name
     const split = attr.type === "set"
 
@@ -14,6 +14,8 @@ export async function loadOptions(attr: AttributeOption, lang: string) {
         .filter((corpus) => name in corpus.struct_attributes || name in corpus.attributes)
         .map((corpus) => corpus.id)
 
+    if (!corpora.length) return []
+
     const data = await getAttrValues(corpora, name, split)
 
     return uniq(data)