Merge pull request #2687 from devoto13/support-parameter-properties

feat: Add basic support for parameter properties

lib/plugin/merge-options.ts

@@ -10,6 +10,7 @@ export interface PluginOptions {
   readonly?: boolean;
   pathToSource?: string;
   debug?: boolean;
+  parameterProperties?: boolean;
 }
 
 const defaultOptions: PluginOptions = {

lib/plugin/visitors/model-class.visitor.ts

@@ -1,7 +1,7 @@
 import { compact, flatten, head } from 'lodash';
 import { posix } from 'path';
 import * as ts from 'typescript';
-import { PropertyAssignment, factory } from 'typescript';
+import { factory, PropertyAssignment } from 'typescript';
 import { ApiHideProperty } from '../../decorators';
 import { PluginOptions } from '../merge-options';
 import { METADATA_FACTORY_NAME } from '../plugin-constants';
@@ -78,6 +78,17 @@ export class ModelClassVisitor extends AbstractFileVisitor {
               sourceFile,
               metadata
             );
+          } else if (
+            options.parameterProperties &&
+            ts.isConstructorDeclaration(node)
+          ) {
+            this.visitConstructorDeclarationNode(
+              node,
+              typeChecker,
+              options,
+              sourceFile,
+              metadata
+            );
           }
           return node;
         };
@@ -176,6 +187,41 @@ export class ModelClassVisitor extends AbstractFileVisitor {
     }
   }
 
+  visitConstructorDeclarationNode(
+    constructorNode: ts.ConstructorDeclaration,
+    typeChecker: ts.TypeChecker,
+    options: PluginOptions,
+    sourceFile: ts.SourceFile,
+    metadata: ClassMetadata
+  ) {
+    constructorNode.forEachChild((node) => {
+      if (
+        ts.isParameter(node) &&
+        node.modifiers != null &&
+        node.modifiers.some(
+          (modifier: ts.Modifier) =>
+            modifier.kind === ts.SyntaxKind.ReadonlyKeyword ||
+            modifier.kind === ts.SyntaxKind.PrivateKeyword ||
+            modifier.kind === ts.SyntaxKind.PublicKeyword ||
+            modifier.kind === ts.SyntaxKind.ProtectedKeyword
+        )
+      ) {
+        const objectLiteralExpr = this.createDecoratorObjectLiteralExpr(
+          factory,
+          node,
+          typeChecker,
+          factory.createNodeArray(),
+          options,
+          sourceFile.fileName,
+          sourceFile
+        );
+
+        const propertyName = node.name.getText();
+        metadata[propertyName] = objectLiteralExpr;
+      }
+    });
+  }
+
   addMetadataFactory(
     factory: ts.NodeFactory,
     node: ts.ClassDeclaration,
@@ -254,7 +300,10 @@ export class ModelClassVisitor extends AbstractFileVisitor {
 
   createDecoratorObjectLiteralExpr(
     factory: ts.NodeFactory,
-    node: ts.PropertyDeclaration | ts.PropertySignature,
+    node:
+      | ts.PropertyDeclaration
+      | ts.PropertySignature
+      | ts.ParameterDeclaration,
     typeChecker: ts.TypeChecker,
     existingProperties: ts.NodeArray<ts.PropertyAssignment> = factory.createNodeArray(),
     options: PluginOptions = {},
@@ -278,7 +327,7 @@ export class ModelClassVisitor extends AbstractFileVisitor {
         hostFilename,
         options
       ),
-      ...this.createDescriptionAndTsDocTagPropertyAssigments(
+      ...this.createDescriptionAndTsDocTagPropertyAssignments(
         factory,
         node,
         typeChecker,
@@ -301,7 +350,10 @@ export class ModelClassVisitor extends AbstractFileVisitor {
         options
       )
     ];
-    if (options.classValidatorShim) {
+    if (
+      (ts.isPropertyDeclaration(node) || ts.isPropertySignature(node)) &&
+      options.classValidatorShim
+    ) {
       properties.push(
         this.createValidationPropertyAssignments(factory, node, options)
       );
@@ -445,7 +497,10 @@ export class ModelClassVisitor extends AbstractFileVisitor {
 
   createEnumPropertyAssignment(
     factory: ts.NodeFactory,
-    node: ts.PropertyDeclaration | ts.PropertySignature,
+    node:
+      | ts.PropertyDeclaration
+      | ts.PropertySignature
+      | ts.ParameterDeclaration,
     typeChecker: ts.TypeChecker,
     existingProperties: ts.NodeArray<ts.PropertyAssignment>,
     hostFilename: string,
@@ -512,18 +567,24 @@ export class ModelClassVisitor extends AbstractFileVisitor {
 
   createDefaultPropertyAssignment(
     factory: ts.NodeFactory,
-    node: ts.PropertyDeclaration | ts.PropertySignature,
+    node:
+      | ts.PropertyDeclaration
+      | ts.PropertySignature
+      | ts.ParameterDeclaration,
     existingProperties: ts.NodeArray<ts.PropertyAssignment>,
     options: PluginOptions
   ) {
     const key = 'default';
     if (hasPropertyKey(key, existingProperties)) {
       return undefined;
     }
-    let initializer = (node as ts.PropertyDeclaration).initializer;
-    if (!initializer) {
+    if (ts.isPropertySignature(node)) {
       return undefined;
     }
+    if (node.initializer == null) {
+      return undefined;
+    }
+    let initializer = node.initializer;
     if (ts.isAsExpression(initializer)) {
       initializer = initializer.expression;
     }
@@ -745,9 +806,12 @@ export class ModelClassVisitor extends AbstractFileVisitor {
     metadata[propertyName] = objectLiteral;
   }
 
-  createDescriptionAndTsDocTagPropertyAssigments(
+  createDescriptionAndTsDocTagPropertyAssignments(
     factory: ts.NodeFactory,
-    node: ts.PropertyDeclaration | ts.PropertySignature,
+    node:
+      | ts.PropertyDeclaration
+      | ts.PropertySignature
+      | ts.ParameterDeclaration,
     typeChecker: ts.TypeChecker,
     existingProperties: ts.NodeArray<ts.PropertyAssignment> = factory.createNodeArray(),
     options: PluginOptions = {},

test/plugin/fixtures/parameter-property.dto.ts

@@ -0,0 +1,49 @@
+export const parameterPropertyDtoText = `
+export class ParameterPropertyDto {
+  constructor(
+    readonly readonlyValue?: string, 
+    private privateValue: string | null, 
+    public publicValue: ItemDto[], 
+    regularParameter: string
+    protected protectedValue: string = '1234', 
+) {}
+}
+
+export enum LettersEnum {
+  A = 'A',
+  B = 'B',
+  C = 'C'
+}
+
+export class ItemDto {
+  constructor(readonly enumValue: LettersEnum) {}
+}
+`;
+
+export const parameterPropertyDtoTextTranspiled = `import * as openapi from "@nestjs/swagger";
+export class ParameterPropertyDto {
+    constructor(readonlyValue, privateValue, publicValue, regularParameter, protectedValue = '1234') {
+        this.readonlyValue = readonlyValue;
+        this.privateValue = privateValue;
+        this.publicValue = publicValue;
+        this.protectedValue = protectedValue;
+    }
+    static _OPENAPI_METADATA_FACTORY() {
+        return { readonlyValue: { required: false, type: () => String }, privateValue: { required: true, type: () => String, nullable: true }, publicValue: { required: true, type: () => [require("./parameter-property.dto").ItemDto] }, protectedValue: { required: true, type: () => String, default: "1234" } };
+    }
+}
+export var LettersEnum;
+(function (LettersEnum) {
+    LettersEnum["A"] = "A";
+    LettersEnum["B"] = "B";
+    LettersEnum["C"] = "C";
+})(LettersEnum || (LettersEnum = {}));
+export class ItemDto {
+    constructor(enumValue) {
+        this.enumValue = enumValue;
+    }
+    static _OPENAPI_METADATA_FACTORY() {
+        return { enumValue: { required: true, enum: require("./parameter-property.dto").LettersEnum } };
+    }
+}
+`;

test/plugin/model-class-visitor.spec.ts

@@ -30,6 +30,10 @@ import {
   stringLiteralDtoText,
   stringLiteralDtoTextTranspiled
 } from './fixtures/string-literal.dto';
+import {
+  parameterPropertyDtoText,
+  parameterPropertyDtoTextTranspiled
+} from './fixtures/parameter-property.dto';
 
 describe('API model properties', () => {
   it('should add the metadata factory when no decorators exist, and generated propertyKey is title', () => {
@@ -240,4 +244,35 @@ describe('API model properties', () => {
     });
     expect(result.outputText).toEqual(stringLiteralDtoTextTranspiled);
   });
+
+  it('should support & understand parameter properties', () => {
+    const options: ts.CompilerOptions = {
+      module: ts.ModuleKind.ES2020,
+      target: ts.ScriptTarget.ES2020,
+      newLine: ts.NewLineKind.LineFeed,
+      noEmitHelpers: true,
+      experimentalDecorators: true,
+      strict: true
+    };
+    const filename = 'parameter-property.dto.ts';
+    const fakeProgram = ts.createProgram([filename], options);
+
+    const result = ts.transpileModule(parameterPropertyDtoText, {
+      compilerOptions: options,
+      fileName: filename,
+      transformers: {
+        before: [
+          before(
+            {
+              introspectComments: true,
+              classValidatorShim: true,
+              parameterProperties: true
+            },
+            fakeProgram
+          )
+        ]
+      }
+    });
+    expect(result.outputText).toEqual(parameterPropertyDtoTextTranspiled);
+  });
 });