fixing issue with expressions pending (#125520)

src/plugins/expressions/common/execution/execution_contract.test.ts

@@ -6,11 +6,13 @@
  * Side Public License, v 1.
  */
 
+import { Observable, Subscriber } from 'rxjs';
 import { first } from 'rxjs/operators';
 import { Execution } from './execution';
 import { parseExpression } from '../ast';
 import { createUnitTestExecutor } from '../test_helpers';
 import { ExecutionContract } from './execution_contract';
+import { ExpressionFunctionDefinition } from '../expression_functions';
 
 const createExecution = (
   expression: string = 'foo bar=123',
@@ -117,11 +119,40 @@ describe('ExecutionContract', () => {
       const contract = new ExecutionContract(execution);
 
       execution.start();
-      await execution.result.pipe(first()).toPromise();
       execution.state.get().state = 'error';
 
       expect(contract.isPending).toBe(false);
       expect(execution.state.get().state).toBe('error');
     });
+
+    test('is true when execution is in progress but got partial result, is false once we get final result', async () => {
+      let mySubscriber: Subscriber<number>;
+      const arg = new Observable((subscriber) => {
+        mySubscriber = subscriber;
+        subscriber.next(1);
+      });
+
+      const observable: ExpressionFunctionDefinition<'observable', unknown, {}, unknown> = {
+        name: 'observable',
+        args: {},
+        help: '',
+        fn: () => arg,
+      };
+      const executor = createUnitTestExecutor();
+      executor.registerFunction(observable);
+
+      const execution = executor.createExecution('observable');
+      execution.start(null);
+      await execution.result.pipe(first()).toPromise();
+
+      expect(execution.contract.isPending).toBe(true);
+      expect(execution.state.get().state).toBe('result');
+
+      mySubscriber!.next(2);
+      mySubscriber!.complete();
+
+      expect(execution.contract.isPending).toBe(false);
+      expect(execution.state.get().state).toBe('result');
+    });
   });
 });

src/plugins/expressions/common/execution/execution_contract.ts

@@ -19,8 +19,8 @@ import { Adapters } from '../../../inspector/common/adapters';
  */
 export class ExecutionContract<Input = unknown, Output = unknown, InspectorAdapters = unknown> {
   public get isPending(): boolean {
-    const state = this.execution.state.get().state;
-    const finished = state === 'error' || state === 'result';
+    const { state, result } = this.execution.state.get();
+    const finished = state === 'error' || (state === 'result' && !result?.partial);
     return !finished;
   }