fix(db-postgres): relationship query pagination (#5802)

test/collections-rest/int.spec.ts

@@ -1191,40 +1191,182 @@ describe('collections-rest', () => {
         expect(result.docs).toEqual([post1])
       })
 
-      describe('limit', () => {
+      describe('pagination', () => {
+        let relatedDoc
+
         beforeEach(async () => {
-          await mapAsync([...Array(50)], async (_, i) =>
-            createPost({ number: i, title: 'limit-test' }),
-          )
+          relatedDoc = await payload.create({
+            collection: relationSlug,
+            data: {
+              name: 'test',
+            },
+          })
+          await mapAsync([...Array(10)], async (_, i) => {
+            await createPost({
+              number: i,
+              relationField: relatedDoc.id as string,
+              title: 'paginate-test',
+            })
+          })
         })
 
-        it('should query a limited set of docs', async () => {
-          const { result, status } = await client.find<Post>({
-            limit: 15,
+        it('should paginate with where query', async () => {
+          const { result: page1 } = await client.find({
+            limit: 4,
             query: {
               title: {
-                equals: 'limit-test',
+                equals: 'paginate-test',
               },
             },
           })
 
-          expect(status).toEqual(200)
-          expect(result.docs).toHaveLength(15)
-        })
-
-        it('should query all docs when limit=0', async () => {
-          const { result, status } = await client.find<Post>({
-            limit: 0,
+          const { result: page2 } = await client.find({
+            limit: 4,
+            page: 2,
             query: {
               title: {
-                equals: 'limit-test',
+                equals: 'paginate-test',
               },
             },
           })
 
-          expect(status).toEqual(200)
-          expect(result.docs).toHaveLength(50)
-          expect(result.totalPages).toEqual(1)
+          const { result: page3 } = await client.find({
+            limit: 4,
+            page: 3,
+            query: {
+              title: {
+                equals: 'paginate-test',
+              },
+            },
+          })
+
+          expect(page1.hasNextPage).toStrictEqual(true)
+          expect(page1.hasPrevPage).toStrictEqual(false)
+          expect(page1.limit).toStrictEqual(4)
+          expect(page1.nextPage).toStrictEqual(2)
+          expect(page1.page).toStrictEqual(1)
+          expect(page1.pagingCounter).toStrictEqual(1)
+          expect(page1.prevPage).toStrictEqual(null)
+          expect(page1.totalDocs).toStrictEqual(10)
+          expect(page1.totalPages).toStrictEqual(3)
+
+          expect(page2.hasNextPage).toStrictEqual(true)
+          expect(page2.hasPrevPage).toStrictEqual(true)
+          expect(page2.limit).toStrictEqual(4)
+          expect(page2.nextPage).toStrictEqual(3)
+          expect(page2.page).toStrictEqual(2)
+          expect(page2.pagingCounter).toStrictEqual(5)
+          expect(page2.prevPage).toStrictEqual(1)
+          expect(page2.totalDocs).toStrictEqual(10)
+          expect(page2.totalPages).toStrictEqual(3)
+
+          expect(page3.hasNextPage).toStrictEqual(false)
+          expect(page3.hasPrevPage).toStrictEqual(true)
+          expect(page3.limit).toStrictEqual(4)
+          expect(page3.nextPage).toStrictEqual(null)
+          expect(page3.page).toStrictEqual(3)
+          expect(page3.pagingCounter).toStrictEqual(9)
+          expect(page3.prevPage).toStrictEqual(2)
+          expect(page3.totalDocs).toStrictEqual(10)
+          expect(page3.totalPages).toStrictEqual(3)
+        })
+
+        it('should paginate with where query on relationships', async () => {
+          const { result: page1 } = await client.find({
+            limit: 4,
+            query: {
+              relationField: {
+                equals: relatedDoc.id,
+              },
+            },
+          })
+
+          const { result: page2 } = await client.find({
+            limit: 4,
+            page: 2,
+            query: {
+              relationField: {
+                equals: relatedDoc.id,
+              },
+            },
+          })
+
+          const { result: page3 } = await client.find({
+            limit: 4,
+            page: 3,
+            query: {
+              relationField: {
+                equals: relatedDoc.id,
+              },
+            },
+          })
+
+          expect(page1.hasNextPage).toStrictEqual(true)
+          expect(page1.hasPrevPage).toStrictEqual(false)
+          expect(page1.limit).toStrictEqual(4)
+          expect(page1.nextPage).toStrictEqual(2)
+          expect(page1.page).toStrictEqual(1)
+          expect(page1.pagingCounter).toStrictEqual(1)
+          expect(page1.prevPage).toStrictEqual(null)
+          expect(page1.totalDocs).toStrictEqual(10)
+          expect(page1.totalPages).toStrictEqual(3)
+
+          expect(page2.hasNextPage).toStrictEqual(true)
+          expect(page2.hasPrevPage).toStrictEqual(true)
+          expect(page2.limit).toStrictEqual(4)
+          expect(page2.nextPage).toStrictEqual(3)
+          expect(page2.page).toStrictEqual(2)
+          expect(page2.pagingCounter).toStrictEqual(5)
+          expect(page2.prevPage).toStrictEqual(1)
+          expect(page2.totalDocs).toStrictEqual(10)
+          expect(page2.totalPages).toStrictEqual(3)
+
+          expect(page3.hasNextPage).toStrictEqual(false)
+          expect(page3.hasPrevPage).toStrictEqual(true)
+          expect(page3.limit).toStrictEqual(4)
+          expect(page3.nextPage).toStrictEqual(null)
+          expect(page3.page).toStrictEqual(3)
+          expect(page3.pagingCounter).toStrictEqual(9)
+          expect(page3.prevPage).toStrictEqual(2)
+          expect(page3.totalDocs).toStrictEqual(10)
+          expect(page3.totalPages).toStrictEqual(3)
+        })
+
+        describe('limit', () => {
+          beforeEach(async () => {
+            await mapAsync([...Array(50)], async (_, i) =>
+              createPost({ number: i, title: 'limit-test' }),
+            )
+          })
+
+          it('should query a limited set of docs', async () => {
+            const { result, status } = await client.find<Post>({
+              limit: 15,
+              query: {
+                title: {
+                  equals: 'limit-test',
+                },
+              },
+            })
+
+            expect(status).toStrictEqual(200)
+            expect(result.docs).toHaveLength(15)
+          })
+
+          it('should query all docs when limit=0', async () => {
+            const { result, status } = await client.find<Post>({
+              limit: 0,
+              query: {
+                title: {
+                  equals: 'limit-test',
+                },
+              },
+            })
+
+            expect(status).toStrictEqual(200)
+            expect(result.docs).toHaveLength(50)
+            expect(result.totalPages).toStrictEqual(1)
+          })
         })
       })