Minor change to discoveryMechanism's api

packages/dataverse/src/derivations/prism/discoveryMechanism.ts

@@ -10,12 +10,15 @@ function createMechanism() {
 
   type Collector = (d: IDerivation<$IntentionalAny>) => void
 
-  const collectObservedDependencies = (
-    cb: () => void,
-    collector: Collector,
-  ) => {
+  const pushCollector = (collector: Collector): void => {
     stack.push(collector)
-    cb()
+  }
+
+  const popCollector = (collector: Collector): void => {
+    const existing = stack.peek()
+    if (existing !== collector) {
+      throw new Error(`Popped collector is not on top of the stack`)
+    }
     stack.pop()
   }
 
@@ -46,18 +49,14 @@ function createMechanism() {
     stack.pop()
   }
 
-  const isCollectingDependencies = () => {
-    return stack.peek() !== noopCollector
-  }
-
   return {
     type: 'Dataverse_discoveryMechanism' as 'Dataverse_discoveryMechanism',
-    collectObservedDependencies,
     startIgnoringDependencies,
     stopIgnoringDependencies,
     reportResolutionStart,
     reportResolutionEnd,
-    isCollectingDependencies,
+    pushCollector,
+    popCollector,
   }
 }
 
@@ -85,10 +84,10 @@ function getSharedMechanism(): ReturnType<typeof createMechanism> {
 }
 
 export const {
-  collectObservedDependencies,
   startIgnoringDependencies,
   stopIgnoringDependencies,
   reportResolutionEnd,
   reportResolutionStart,
-  isCollectingDependencies,
+  pushCollector,
+  popCollector,
 } = getSharedMechanism()

packages/dataverse/src/derivations/prism/prism.ts

@@ -4,9 +4,10 @@ import Stack from '../../utils/Stack'
 import AbstractDerivation from '../AbstractDerivation'
 import type {IDerivation} from '../IDerivation'
 import {
-  collectObservedDependencies,
   startIgnoringDependencies,
   stopIgnoringDependencies,
+  pushCollector,
+  popCollector,
 } from './discoveryMechanism'
 
 const voidFn = () => {}
@@ -44,8 +45,14 @@ export class PrismDerivation<V> extends AbstractDerivation<V> {
 
     const newDeps: Set<IDerivation<unknown>> = new Set()
     this._cacheOfDendencyValues.clear()
-    collectObservedDependencies(
-      () => {
+
+    const collector = (observedDep: IDerivation<unknown>): void => {
+      newDeps.add(observedDep)
+      this._addDependency(observedDep)
+    }
+
+    pushCollector(collector)
+
     hookScopeStack.push(this._prismScope)
     try {
       value = this._fn()
@@ -60,12 +67,8 @@ export class PrismDerivation<V> extends AbstractDerivation<V> {
         )
       }
     }
-      },
-      (observedDep) => {
-        newDeps.add(observedDep)
-        this._addDependency(observedDep)
-      },
-    )
+
+    popCollector(collector)
 
     this._dependencies.forEach((dep) => {
       if (!newDeps.has(dep)) {