Updating replaceWith to take an Expr

Author: MarkDuckworth

packages/firestore/src/lite-api/pipeline.ts

@@ -599,7 +599,7 @@ export class Pipeline implements ProtoSerializable<ProtoPipeline> {
    * // }
    *
    * // Emit parents as document.
-   * firestore.pipeline().collection('people').replaceWith(field('parents'));
+   * firestore.pipeline().collection('people').replaceWith('parents');
    *
    * // Output
    * // {
@@ -608,12 +608,50 @@ export class Pipeline implements ProtoSerializable<ProtoPipeline> {
    * // }
    * ```
    *
-   * @param fieldValue The {@link Field} field containing the nested map.
+   * @param fieldName The {@link Field} field containing the nested map.
    * @return A new {@code Pipeline} object with this stage appended to the stage list.
    */
-  replaceWith(fieldValue: Field | string): Pipeline {
-    const fieldExpr =
-      typeof fieldValue === 'string' ? field(fieldValue) : fieldValue;
+  replaceWith(fieldName: string): Pipeline;
+
+  /**
+   * Fully overwrites all fields in a document with those coming from a map.
+   *
+   * <p>This stage allows you to emit a map value as a document. Each key of the map becomes a field
+   * on the document that contains the corresponding value.
+   *
+   * <p>Example:
+   *
+   * ```typescript
+   * // Input.
+   * // {
+   * //  'name': 'John Doe Jr.',
+   * //  'parents': {
+   * //    'father': 'John Doe Sr.',
+   * //    'mother': 'Jane Doe'
+   * //   }
+   * // }
+   *
+   * // Emit parents as document.
+   * firestore.pipeline().collection('people').replaceWith(map({
+   *   foo: 'bar',
+   *   info: {
+   *     name: field('name')
+   *   }
+   * }));
+   *
+   * // Output
+   * // {
+   * //  'father': 'John Doe Sr.',
+   * //  'mother': 'Jane Doe'
+   * // }
+   * ```
+   *
+   * @param expr An {@link Expr} that when returned evaluates to a map.
+   * @return A new {@code Pipeline} object with this stage appended to the stage list.
+   */
+  replaceWith(expr: Expr): Pipeline;
+  replaceWith(value: Expr | string): Pipeline {
+    const fieldExpr = typeof value === 'string' ? field(value) : value;
     this.readUserData('replaceWith', fieldExpr);
     return this._addStage(new Replace(fieldExpr, 'full_replace'));
   }

packages/firestore/src/lite-api/stage.ts

@@ -467,7 +467,7 @@ export class Replace implements Stage {
   name = 'replace_with';
 
   constructor(
-    private field: Field,
+    private field: Expr,
     private mode:
       | 'full_replace'
       | 'merge_prefer_nest'

packages/firestore/test/integration/api/pipeline.test.ts

@@ -1297,8 +1297,8 @@ apiDescribe.only('Pipelines', persistence => {
       });
     });
 
-    describe('replace stage', () => {
-      it('run pipleine with replace', async () => {
+    describe('replaceWith stage', () => {
+      it('run pipeline with replaceWith field name', async () => {
         const snapshot = await execute(
           firestore
             .pipeline()
@@ -1312,6 +1312,27 @@ apiDescribe.only('Pipelines', persistence => {
           others: { unknown: { year: 1980 } }
         });
       });
+
+      it('run pipeline with replaceWith Expr result', async () => {
+        const snapshot = await execute(
+          firestore
+            .pipeline()
+            .collection(randomCol.path)
+            .where(eq('title', "The Hitchhiker's Guide to the Galaxy"))
+            .replaceWith(
+              map({
+                foo: 'bar',
+                baz: {
+                  title: field('title')
+                }
+              })
+            )
+        );
+        expectResults(snapshot, {
+          foo: 'bar',
+          baz: { title: "The Hitchhiker's Guide to the Galaxy" }
+        });
+      });
     });
 
     describe('sample stage', () => {