Extract RecordTransformBuffer interface

By extracting the `RecordTransformBuffer` from the class that implements it, now called `SimpleRecordTransformBuffer`, we do the following:

* Unlock experimentation with other implementations of `RecordTransformBuffer`.
* Remove the circular dependency between `sync-record-cache` and `record-transform-buffer`. This cycle, while still "legal", highlighted an issue in esbuild.
* Require that an _instance_ of a `RecordTransformBuffer` be passed into record caches on construction, which simplifies the settings.

Note: To keep behavior consistent, all the standard derived cache classes now override `_getTransformBuffer` to construct a `SimpleRecordTransformBuffer` if a `transformBuffer` hasn't been provided in settings.

packages/@orbit/indexeddb/src/indexeddb-cache.ts

@@ -13,7 +13,9 @@ import {
   AsyncRecordCacheSettings,
   RecordCacheQueryOptions,
   RecordCacheTransformOptions,
-  RecordCacheUpdateDetails
+  RecordCacheUpdateDetails,
+  RecordTransformBuffer,
+  SimpleRecordTransformBuffer
 } from '@orbit/record-cache';
 import { supportsIndexedDB } from './lib/indexeddb';
 import { RequestOptions } from '@orbit/data';
@@ -564,6 +566,22 @@ export class IndexedDBCache<
   // Protected methods
   /////////////////////////////////////////////////////////////////////////////
 
+  /**
+   * Override `_getTransformBuffer` on base `AsyncRecordCache` to provide a
+   * `transformBuffer` if a custom one hasn't been provided via the constructor
+   * setting.
+   */
+  protected _getTransformBuffer(): RecordTransformBuffer {
+    if (this._transformBuffer === undefined) {
+      const { schema, keyMap } = this;
+      this._transformBuffer = new SimpleRecordTransformBuffer({
+        schema,
+        keyMap
+      });
+    }
+    return this._transformBuffer;
+  }
+
   protected async _getAllRecords(): Promise<InitializedRecord[]> {
     if (!this._db) return Promise.reject(DB_NOT_OPEN);
 

packages/@orbit/local-storage/src/local-storage-cache.ts

@@ -11,6 +11,8 @@ import {
   RecordCacheTransformOptions,
   RecordCacheUpdateDetails,
   RecordRelationshipIdentity,
+  RecordTransformBuffer,
+  SimpleRecordTransformBuffer,
   SyncRecordCache,
   SyncRecordCacheSettings
 } from '@orbit/record-cache';
@@ -261,4 +263,24 @@ export class LocalStorageCache<
       processor.upgrade();
     }
   }
+
+  /////////////////////////////////////////////////////////////////////////////
+  // Protected methods
+  /////////////////////////////////////////////////////////////////////////////
+
+  /**
+   * Override `_getTransformBuffer` on base `SyncRecordCache` to provide a
+   * `transformBuffer` if a custom one hasn't been provided via the constructor
+   * setting.
+   */
+  protected _getTransformBuffer(): RecordTransformBuffer {
+    if (this._transformBuffer === undefined) {
+      const { schema, keyMap } = this;
+      this._transformBuffer = new SimpleRecordTransformBuffer({
+        schema,
+        keyMap
+      });
+    }
+    return this._transformBuffer;
+  }
 }

packages/@orbit/memory/src/memory-cache.ts

@@ -11,6 +11,8 @@ import {
   RecordCacheTransformOptions,
   RecordCacheUpdateDetails,
   RecordRelationshipIdentity,
+  RecordTransformBuffer,
+  SimpleRecordTransformBuffer,
   SyncRecordCache,
   SyncRecordCacheSettings
 } from '@orbit/record-cache';
@@ -256,6 +258,22 @@ export class MemoryCache<
   // Protected methods
   /////////////////////////////////////////////////////////////////////////////
 
+  /**
+   * Override `_getTransformBuffer` on base `SyncRecordCache` to provide a
+   * `transformBuffer` if a custom one hasn't been provided via the constructor
+   * setting.
+   */
+  protected _getTransformBuffer(): RecordTransformBuffer {
+    if (this._transformBuffer === undefined) {
+      const { schema, keyMap } = this;
+      this._transformBuffer = new SimpleRecordTransformBuffer({
+        schema,
+        keyMap
+      });
+    }
+    return this._transformBuffer;
+  }
+
   protected _resetInverseRelationships(
     base?: MemoryCache<QO, TO, QB, TB, QRD, TRD>
   ): void {

packages/@orbit/record-cache/src/async-record-cache.ts

@@ -1,4 +1,4 @@
-import { Orbit } from '@orbit/core';
+import { Assertion, Orbit } from '@orbit/core';
 import {
   buildQuery,
   buildTransform,
@@ -60,12 +60,8 @@ import {
   RecordCacheSettings,
   RecordCacheTransformOptions
 } from './record-cache';
-import {
-  RecordTransformBuffer,
-  RecordTransformBufferClass
-} from './record-transform-buffer';
+import { RecordTransformBuffer } from './record-transform-buffer';
 import { PatchResult, RecordCacheUpdateDetails } from './response';
-import { SyncRecordCacheSettings } from './sync-record-cache';
 
 const { assert, deprecate } = Orbit;
 
@@ -80,8 +76,7 @@ export interface AsyncRecordCacheSettings<
   transformOperators?: Dict<AsyncTransformOperator>;
   inverseTransformOperators?: Dict<AsyncInverseTransformOperator>;
   debounceLiveQueries?: boolean;
-  transformBufferClass?: RecordTransformBufferClass;
-  transformBufferSettings?: SyncRecordCacheSettings<QO, TO>;
+  transformBuffer?: RecordTransformBuffer;
 }
 
 export abstract class AsyncRecordCache<
@@ -103,8 +98,6 @@ export abstract class AsyncRecordCache<
   protected _inverseTransformOperators: Dict<AsyncInverseTransformOperator>;
   protected _debounceLiveQueries: boolean;
   protected _transformBuffer?: RecordTransformBuffer;
-  protected _transformBufferClass?: RecordTransformBufferClass;
-  protected _transformBufferSettings?: SyncRecordCacheSettings<QO, TO>;
 
   constructor(settings: AsyncRecordCacheSettings<QO, TO, QB, TB>) {
     super(settings);
@@ -115,6 +108,7 @@ export abstract class AsyncRecordCache<
     this._inverseTransformOperators =
       settings.inverseTransformOperators ?? AsyncInverseTransformOperators;
     this._debounceLiveQueries = settings.debounceLiveQueries !== false;
+    this._transformBuffer = settings.transformBuffer;
 
     const processors: AsyncOperationProcessorClass[] = settings.processors
       ? settings.processors
@@ -494,14 +488,9 @@ export abstract class AsyncRecordCache<
 
   protected _getTransformBuffer(): RecordTransformBuffer {
     if (this._transformBuffer === undefined) {
-      let transformBufferClass =
-        this._transformBufferClass ?? RecordTransformBuffer;
-      let settings = this._transformBufferSettings ?? { schema: this.schema };
-      settings.schema = settings.schema ?? this.schema;
-      settings.keyMap = settings.keyMap ?? this.keyMap;
-      this._transformBuffer = new transformBufferClass(settings);
-    } else {
-      this._transformBuffer.reset();
+      throw new Assertion(
+        'transformBuffer must be provided to cache via constructor settings'
+      );
     }
     return this._transformBuffer;
   }
@@ -520,6 +509,7 @@ export abstract class AsyncRecordCache<
     const relatedRecords = inverseRelationships.map((ir) => ir.record);
     Array.prototype.push.apply(records, relatedRecords);
 
+    buffer.resetState();
     buffer.setRecordsSync(await this.getRecordsAsync(records));
     buffer.addInverseRelationshipsSync(inverseRelationships);
 

packages/@orbit/record-cache/src/index.ts

@@ -2,6 +2,7 @@ export * from './response';
 export * from './record-accessor';
 export * from './record-cache';
 export * from './record-transform-buffer';
+export * from './simple-record-transform-buffer';
 
 export * from './async-record-cache';
 export * from './async-operation-processor';