feat: fix isArray detection for optional properties

Author: darraghoriordan

src/rules/validate-non-primitves-needs-type-decorator/validateNonPrimitiveNeedsDecorators.test.ts

@@ -14,6 +14,30 @@ const ruleTester = new RuleTester({
 
 ruleTester.run("validated-non-primitive-property-needs-type-decorator", rule, {
     valid: [
+        {
+            // is a primitive type array - doesn't need type (from https://github.com/darraghoriordan/eslint-plugin-nestjs-typed/issues/22)
+            code: `
+            class ExampleDto {
+                @ApiProperty({
+                  isArray: true,
+                })
+                @Allow()
+               exampleProperty!: string[];
+              }
+    `,
+        },
+        {
+            // is an OPTIONAL primitive type array - doesn't need type (from https://github.com/darraghoriordan/eslint-plugin-nestjs-typed/issues/22)
+            code: `
+            class ExampleDto {
+                @ApiPropertyOptional({
+                  isArray: true,
+                })
+                @Allow()
+               exampleProperty?: string[];
+              }
+    `,
+        },
         {
             // scenario from https://github.com/darraghoriordan/eslint-plugin-nestjs-typed/issues/21
             code: `
@@ -83,7 +107,7 @@ ruleTester.run("validated-non-primitive-property-needs-type-decorator", rule, {
         `,
         },
         {
-            // is an array - should have type
+            // is an array - should have type and has it so pass!
             code: `
             export class CreateOrganisationDto {
                 @ApiProperty({ type: Person, isArray: true })
@@ -103,6 +127,23 @@ ruleTester.run("validated-non-primitive-property-needs-type-decorator", rule, {
                 @ValidateNested({each:true})
                 members!: Foo[];
             }
+    `,
+            errors: [
+                {
+                    messageId: "shouldUseTypeDecorator",
+                },
+            ],
+        },
+        {
+            // is an OPTIONAL array - should have type
+            code: `
+            export class Foo {}
+            
+            export class CreateOrganisationDto {
+                @ApiProperty({ type: Person, isArray: true })
+                @ValidateNested({each:true})
+                members?: Foo[];
+            }
     `,
             errors: [
                 {

src/rules/validate-non-primitves-needs-type-decorator/validateNonPrimitiveNeedsDecorators.ts

@@ -4,7 +4,6 @@ import {createRule} from "../../utils/createRule";
 import {typedTokenHelpers} from "../../utils/typedTokenHelpers";
 import {getParserServices} from "@typescript-eslint/experimental-utils/dist/eslint-utils";
 import {classValidatorDecorators} from "../../utils/classValidatorDecorators";
-//import util from "util";
 
 const primitiveTypes = new Set([
     AST_NODE_TYPES.TSStringKeyword,

src/utils/typedTokenHelpers.ts

@@ -23,7 +23,17 @@ export const typedTokenHelpers = {
         parserService: ParserServices,
         checker: ts.TypeChecker
     ): boolean {
+        if (
+            (node as TSESTree.PropertyDefinition)?.typeAnnotation
+                ?.typeAnnotation?.type === TSESTree.AST_NODE_TYPES.TSArrayType
+        ) {
+            return true;
+        }
+
         const nodeType = this.getNodeType(node, parserService, checker);
+        if (checker.isArrayType(nodeType)) {
+            return true;
+        }
         for (const t of unionTypeParts(nodeType)) {
             if (!checker.isArrayType(t)) {
                 return false;