fix: resolve FindOptionsOrder.nulls to allow FIRST/LAST in uppercase

src/query-builder/SelectQueryBuilder.ts

@@ -3890,9 +3890,9 @@ export class SelectQueryBuilder<Entity>
                         ? (order[key] as any).nulls
                         : undefined
                 nulls =
-                    nulls === "first"
+                    nulls?.toLowerCase() === "first"
                         ? "NULLS FIRST"
-                        : nulls === "last"
+                        : nulls?.toLowerCase() === "last"
                         ? "NULLS LAST"
                         : undefined
 

test/github-issues/8970/entities/TestEntity.ts

@@ -0,0 +1,16 @@
+import {
+    Column,
+    Entity,
+    ObjectIdColumn,
+    PrimaryGeneratedColumn,
+} from "../../../../src"
+
+@Entity()
+export class TestEntity {
+    @ObjectIdColumn()
+    @PrimaryGeneratedColumn()
+    id: number
+
+    @Column({ nullable: true })
+    testColumn: string
+}

test/github-issues/8970/issue-8970.ts

@@ -0,0 +1,69 @@
+import "reflect-metadata"
+import {
+    closeTestingConnections,
+    createTestingConnections,
+    reloadTestingDatabases,
+} from "../../utils/test-utils"
+import { DataSource } from "../../../src"
+import { TestEntity } from "./entities/TestEntity"
+import { expect } from "chai"
+
+describe("query builder order nulls first/last", async () => {
+    let dataSources: DataSource[]
+
+    before(async () => {
+        dataSources = await createTestingConnections({
+            entities: [__dirname + "/entities/*{.js,.ts}"],
+            enabledDrivers: ["postgres", "sqlite", "better-sqlite3"],
+            schemaCreate: true,
+            dropSchema: false,
+        })
+    })
+    beforeEach(() => reloadTestingDatabases(dataSources))
+    after(() => closeTestingConnections(dataSources))
+
+    const runTest = async (
+        dataSource: DataSource,
+        firstOrLastString: "first" | "FIRST" | "last" | "LAST",
+    ) => {
+        const repository = dataSource.getRepository(TestEntity)
+
+        const testArray = await repository.find({
+            order: {
+                testColumn: { direction: "DESC", nulls: firstOrLastString },
+            },
+        })
+        const test =
+            ["first", "FIRST"].indexOf(firstOrLastString) !== -1
+                ? testArray.shift()
+                : testArray.pop()
+
+        expect(test?.testColumn).to.be.null
+    }
+
+    it(`should work with uppercase/lowercase first/last`, async () => {
+        return Promise.all(
+            dataSources.map(async (dataSource) => {
+                const repository = dataSource.getRepository(TestEntity)
+
+                for (let i = 0; i < 5; i++) {
+                    const entity = new TestEntity()
+                    entity.testColumn = ""
+
+                    await repository.save(entity)
+                }
+
+                for (let i = 0; i < 5; i++) {
+                    const entity = new TestEntity()
+
+                    await repository.save(entity)
+                }
+
+                await runTest(dataSource, "first")
+                await runTest(dataSource, "FIRST")
+                await runTest(dataSource, "last")
+                await runTest(dataSource, "LAST")
+            }),
+        )
+    })
+})