Soft assert for hydrating story context

ts/util/assert.ts

@@ -4,6 +4,21 @@
 import { getEnvironment, Environment } from '../environment';
 import * as log from '../logging/log';
 
+/**
+ * In production and beta, logs a warning and continues. For development it
+ * starts the debugger.
+ */
+export function softAssert(condition: unknown, message: string): void {
+  if (!condition) {
+    if (getEnvironment() === Environment.Development) {
+      debugger; // eslint-disable-line no-debugger
+    }
+
+    const err = new Error(message);
+    log.warn('softAssert failure:', err && err.stack ? err.stack : err);
+  }
+}
+
 /**
  * In production, logs an error and continues. In all other environments, throws an error.
  */