From d3a1ea23a10428895e0c0e39abdf5dc91273392f Mon Sep 17 00:00:00 2001
From: "tyler.potter" <tyler.potter@datadoghq.com>
Date: Fri, 30 Oct 2026 19:12:25 +0000
Subject: [PATCH] test: cover unassigned prerequisite failure

Require a reached prerequisite with no assignment to fail the full dependency graph. The later logged fallback acts as a canary for evaluators that incorrectly continue the root waterfall.

Environment: Datadog workspace

Co-Authored-By: Codex GPT-5 <noreply@localhost>
---
 .../cases/dependent-flags.json                | 27 ++++++++
 .../dependent-flags/ufc-config.json           | 64 +++++++++++++++++++
 2 files changed, 91 insertions(+)

diff --git a/evaluation-suites/dependent-flags/cases/dependent-flags.json b/evaluation-suites/dependent-flags/cases/dependent-flags.json
index 76cde16..44e92da 100644
--- a/evaluation-suites/dependent-flags/cases/dependent-flags.json
+++ b/evaluation-suites/dependent-flags/cases/dependent-flags.json
@@ -277,6 +277,33 @@
     "targetingKey": "dependent-memoized",
     "variationType": "STRING"
   },
+  {
+    "description": "A reached prerequisite that produces no assignment aborts the graph before a later unconditional root allocation can return or publish an exposure.",
+    "attributes": {},
+    "defaultValue": "caller-default",
+    "flag": "dependent-no-assignment-root",
+    "result": {
+      "reason": "ERROR",
+      "errorCode": "GENERAL",
+      "value": "caller-default"
+    },
+    "targetingKey": "dependent-no-assignment",
+    "variationType": "STRING",
+    "expectations": {
+      "exposures": [],
+      "evaluationEvents": [
+        {
+          "flag": "dependent-no-assignment-parent",
+          "errorCode": "GENERAL"
+        },
+        {
+          "flag": "dependent-no-assignment-root",
+          "errorCode": "GENERAL"
+        }
+      ],
+      "noUnmatchedEvents": true
+    }
+  },
   {
     "description": "A successful prerequisite followed by a missing prerequisite aborts the graph and returns the caller default.",
     "attributes": {},
diff --git a/evaluation-suites/dependent-flags/ufc-config.json b/evaluation-suites/dependent-flags/ufc-config.json
index e4fea47..dd15f93 100644
--- a/evaluation-suites/dependent-flags/ufc-config.json
+++ b/evaluation-suites/dependent-flags/ufc-config.json
@@ -676,6 +676,70 @@
         }
       ]
     },
+    "dependent-no-assignment-parent": {
+      "key": "dependent-no-assignment-parent",
+      "enabled": true,
+      "variationType": "STRING",
+      "variations": {
+        "assigned": {
+          "key": "assigned",
+          "value": "must-never-be-returned-no-assignment-parent"
+        }
+      },
+      "allocations": []
+    },
+    "dependent-no-assignment-root": {
+      "key": "dependent-no-assignment-root",
+      "enabled": true,
+      "variationType": "STRING",
+      "variations": {
+        "matched": {
+          "key": "matched",
+          "value": "must-not-be-returned-no-assignment-match"
+        },
+        "fallback": {
+          "key": "fallback",
+          "value": "must-not-be-returned-no-assignment-fallback"
+        }
+      },
+      "allocations": [
+        {
+          "key": "parent-assigned",
+          "rules": [
+            {
+              "conditions": [
+                {
+                  "flagEvaluation": {
+                    "key": "dependent-no-assignment-parent"
+                  },
+                  "operator": "ONE_OF",
+                  "value": [
+                    "assigned"
+                  ]
+                }
+              ]
+            }
+          ],
+          "splits": [
+            {
+              "variationKey": "matched",
+              "shards": []
+            }
+          ],
+          "doLog": true
+        },
+        {
+          "key": "must-not-be-reached-fallback",
+          "splits": [
+            {
+              "variationKey": "fallback",
+              "shards": []
+            }
+          ],
+          "doLog": true
+        }
+      ]
+    },
     "dependent-atomic-error-root": {
       "key": "dependent-atomic-error-root",
       "enabled": true,