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diff --git a/devtools/client/debugger/src/utils/resource/query.js b/devtools/client/debugger/src/utils/resource/query.js
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+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at <http://mozilla.org/MPL/2.0/>. */
+
+// @flow
+
+import type { ResourceBound, Id, ResourceValues } from "./core";
+
+import {
+  makeResourceQuery,
+  type ResourceQuery,
+  type QueryFilter,
+  type QueryMap,
+  type QueryReduce,
+} from "./base-query";
+
+import {
+  queryCacheWeak,
+  queryCacheShallow,
+  queryCacheStrict,
+  type WeakArgsBound,
+  type ShallowArgsBound,
+} from "./query-cache";
+
+import { memoizeResourceShallow } from "./memoize";
+import { shallowEqual } from "./compare";
+
+export function filterAllIds<R: ResourceBound>(
+  values: ResourceValues<R>
+): Array<Id<R>> {
+  return Object.keys(values);
+}
+
+/**
+ * Create a query function to take a list of IDs and map each Reduceding
+ * resource object into a mapped form.
+ */
+export type WeakQuery<
+  R: ResourceBound,
+  Args: WeakArgsBound,
+  Reduced
+> = ResourceQuery<R, Args, Reduced>;
+export function makeWeakQuery<
+  R: ResourceBound,
+  Args: WeakArgsBound,
+  Mapped,
+  Reduced
+>({
+  filter,
+  map,
+  reduce,
+}: {|
+  filter: QueryFilter<R, Args>,
+  map: QueryMap<R, Args, Mapped>,
+  reduce: QueryReduce<R, Args, Mapped, Reduced>,
+|}): WeakQuery<R, Args, Reduced> {
+  return makeResourceQuery({
+    cache: queryCacheWeak,
+    filter,
+    map: memoizeResourceShallow(map),
+    reduce,
+    resultCompare: shallowEqual,
+  });
+}
+
+/**
+ * Create a query function to take a list of IDs and map each Reduceding
+ * resource object into a mapped form.
+ */
+export type ShallowQuery<R: ResourceBound, Args, Reduced> = ResourceQuery<
+  R,
+  Args,
+  Reduced
+>;
+export function makeShallowQuery<
+  R: ResourceBound,
+  Args: ShallowArgsBound,
+  Mapped,
+  Reduced
+>({
+  filter,
+  map,
+  reduce,
+}: {|
+  filter: QueryFilter<R, Args>,
+  map: QueryMap<R, Args, Mapped>,
+  reduce: QueryReduce<R, Args, Mapped, Reduced>,
+|}): ShallowQuery<R, Args, Reduced> {
+  return makeResourceQuery({
+    cache: queryCacheShallow,
+    filter,
+    map: memoizeResourceShallow(map),
+    reduce,
+    resultCompare: shallowEqual,
+  });
+}
+
+/**
+ * Create a query function to take a list of IDs and map each Reduceding
+ * resource object into a mapped form.
+ */
+export type StrictQuery<R: ResourceBound, Args, Reduced> = ResourceQuery<
+  R,
+  Args,
+  Reduced
+>;
+export function makeStrictQuery<R: ResourceBound, Args, Mapped, Reduced>({
+  filter,
+  map,
+  reduce,
+}: {|
+  filter: QueryFilter<R, Args>,
+  map: QueryMap<R, Args, Mapped>,
+  reduce: QueryReduce<R, Args, Mapped, Reduced>,
+|}): StrictQuery<R, Args, Reduced> {
+  return makeResourceQuery({
+    cache: queryCacheStrict,
+    filter,
+    map: memoizeResourceShallow(map),
+    reduce,
+    resultCompare: shallowEqual,
+  });
+}
+
+/**
+ * Create a query function to take a list of IDs and map each Reduceding
+ * resource object into a mapped form.
+ */
+export type IdQuery<R: ResourceBound, Mapped> = WeakQuery<
+  R,
+  Array<Id<R>>,
+  Array<Mapped>
+>;
+export function makeIdQuery<R: ResourceBound, Mapped>(
+  map: QueryMap<R, void, Mapped>
+): IdQuery<R, Mapped> {
+  return makeWeakQuery({
+    filter: (state, ids) => ids,
+    map: (r, identity) => map(r, identity),
+    reduce: items => items.slice(),
+  });
+}
+
+/**
+ * Create a query function to take a list of IDs and map each Reduceding
+ * resource object into a mapped form.
+ */
+export type LoadQuery<R: ResourceBound, Mapped> = WeakQuery<
+  R,
+  Array<Id<R>>,
+  $ReadOnly<{ [Id<R>]: Mapped }>
+>;
+export function makeLoadQuery<R: ResourceBound, Mapped>(
+  map: QueryMap<R, void, Mapped>
+): LoadQuery<R, Mapped> {
+  return makeWeakQuery({
+    filter: (state, ids) => ids,
+    map: (r, identity) => map(r, identity),
+    reduce: reduceMappedArrayToObject,
+  });
+}
+
+/**
+ * Create a query function that accepts an argument and can filter the
+ * resource items to a subset before mapping each reduced resource.
+ */
+export type FilterQuery<
+  R: ResourceBound,
+  Args: WeakArgsBound,
+  Mapped
+> = WeakQuery<R, Args, $ReadOnly<{ [Id<R>]: Mapped }>>;
+export function makeFilterQuery<R: ResourceBound, Args: WeakArgsBound, Mapped>(
+  filter: (R, Args) => boolean,
+  map: QueryMap<R, Args, Mapped>
+): FilterQuery<R, Args, Mapped> {
+  return makeWeakQuery({
+    filter: (values, args) => {
+      const ids = [];
+      for (const id of Object.keys(values)) {
+        if (filter(values[id], args)) {
+          ids.push(id);
+        }
+      }
+      return ids;
+    },
+    map,
+    reduce: reduceMappedArrayToObject,
+  });
+}
+
+/**
+ * Create a query function that accepts an argument and can filter the
+ * resource items to a subset before mapping each resulting resource.
+ */
+export type ReduceQuery<
+  R: ResourceBound,
+  Args: ShallowArgsBound,
+  Reduced
+> = ShallowQuery<R, Args, Reduced>;
+export function makeReduceQuery<
+  R: ResourceBound,
+  Args: ShallowArgsBound,
+  Mapped,
+  Reduced
+>(
+  map: QueryMap<R, Args, Mapped>,
+  reduce: QueryReduce<R, Args, Mapped, Reduced>
+): ReduceQuery<R, Args, Reduced> {
+  return makeShallowQuery({
+    filter: filterAllIds,
+    map,
+    reduce,
+  });
+}
+
+/**
+ * Create a query function that accepts an argument and can filter the
+ * resource items to a subset before mapping each resulting resource.
+ */
+export type ReduceAllQuery<R: ResourceBound, Reduced> = ShallowQuery<
+  R,
+  void,
+  Reduced
+>;
+export function makeReduceAllQuery<R: ResourceBound, Mapped, Reduced>(
+  map: QueryMap<R, void, Mapped>,
+  reduce: QueryReduce<R, void, Mapped, Reduced>
+): ReduceAllQuery<R, Reduced> {
+  return makeStrictQuery({
+    filter: filterAllIds,
+    map,
+    reduce,
+  });
+}
+
+function reduceMappedArrayToObject<Args, ID, Mapped>(
+  items: $ReadOnlyArray<Mapped>,
+  ids: $ReadOnlyArray<ID>,
+  args: Args
+): { [ID]: Mapped } {
+  return items.reduce((acc: { [ID]: Mapped }, item, i) => {
+    acc[ids[i]] = item;
+    return acc;
+  }, {});
+}