Guard against calling fieldWildcardMatcher or fieldWildcardFilter with undefined (#19865)

src/ui/public/field_wildcard/__tests__/field_wildcard.js

@@ -57,6 +57,18 @@ describe('fieldWildcard', function () {
   });
 
   describe('filter', function () {
+    it('filters nothing when given undefined', function () {
+      const filter = fieldWildcardFilter();
+      const original = [
+        'foo',
+        'bar',
+        'baz',
+        1234
+      ];
+
+      expect(original.filter(filter)).to.eql(original);
+    });
+
     it('filters nothing when given an empty array', function () {
       const filter = fieldWildcardFilter([]);
       const original = [

src/ui/public/field_wildcard/field_wildcard.js

@@ -26,7 +26,8 @@ export function FieldWildcardProvider(config) {
     return new RegExp('^' + glob.split('*').map(escapeRegExp).join('.*') + '$');
   });
 
-  function fieldWildcardMatcher(globs) {
+  // Note that this will return an essentially noop function if globs is undefined.
+  function fieldWildcardMatcher(globs = []) {
     return function matcher(val) {
       // do not test metaFields or keyword
       if (metaFields.indexOf(val) !== -1) {
@@ -36,7 +37,8 @@ export function FieldWildcardProvider(config) {
     };
   }
 
-  function fieldWildcardFilter(globs) {
+  // Note that this will return an essentially noop function if globs is undefined.
+  function fieldWildcardFilter(globs = []) {
     const matcher = fieldWildcardMatcher(globs);
     return function filter(val) {
       return !matcher(val);