Transport structured diagnostics through the pipeline

internal/framework/pipeline/runner_concurrency_test.go

@@ -367,7 +367,8 @@ func TestRunnerBoundsExtractJobsAndStabilizesReverseCompletion(t *testing.T) {
 			case <-ctx.Done():
 				return erasedTypedResult{}, ctx.Err()
 			}
-			return erasedTypedResult{Value: typedValueForLane(lane, request.Chunk.Index), Warnings: []contracts.Warning{{Scope: fmt.Sprintf("lane-%d/chunk-%d", lane, request.Chunk.Index), ReasonCode: "observed", Message: "ordered"}}}, nil
+			scope := fmt.Sprintf("lane-%d/chunk-%d", lane, request.Chunk.Index)
+			return erasedTypedResult{Value: typedValueForLane(lane, request.Chunk.Index), Warnings: []contracts.Warning{{Scope: scope, ReasonCode: "observed", Message: "ordered"}}, Diagnostics: []contracts.ProducerDiagnostic{{Disposition: contracts.DiagnosticDispositionObservation, Category: contracts.DiagnosticCategoryNormalization, ReasonCode: "observed", OccurrenceCount: 1, Samples: []contracts.DiagnosticSample{{Scope: scope, Message: "ordered"}}}}}, nil
 		})
 	}
 
@@ -404,6 +405,24 @@ func TestRunnerBoundsExtractJobsAndStabilizesReverseCompletion(t *testing.T) {
 	if !reflect.DeepEqual(gotScopes, wantScopes) {
 		t.Fatalf("warning order = %#v, want %#v", gotScopes, wantScopes)
 	}
+	if len(result.output.Diagnostics.Groups) != 2 {
+		t.Fatalf("diagnostic groups = %#v, want one deterministic group per lane", result.output.Diagnostics.Groups)
+	}
+	for lane, group := range result.output.Diagnostics.Groups {
+		if group.Origin.LaneID != prepared.Steps[0].lanes[lane].resolved.ID {
+			t.Fatalf("group origin = %#v, want configured lane %q", group.Origin, prepared.Steps[0].lanes[lane].resolved.ID)
+		}
+		indexes := make([]int, len(group.Samples))
+		for index, sample := range group.Samples {
+			if sample.ChunkIndex == nil {
+				t.Fatalf("sample = %#v, want chunk index", sample)
+			}
+			indexes[index] = *sample.ChunkIndex
+		}
+		if !reflect.DeepEqual(indexes, []int{0, 1, 2}) {
+			t.Fatalf("group sample chunk order = %#v, want canonical chunk order", indexes)
+		}
+	}
 }
 
 func TestRunnerStartsLaneContinuationWhileOtherLaneExtractsRemain(t *testing.T) {