fix: correctly select properties of primitives

src/express-validator.spec.ts

@@ -165,3 +165,22 @@ describe('ExpressValidator', () => {
  });
  });
 });
+
+describe('High level tests', () => {
+ const { body } = new ExpressValidator();
+ it('should error when .exists() is used on a nested field of a primitive', async () => {
+ const req = { body: { foo: 'hello' } };
+ const result = await body('foo.nop').exists().run(req);
+ expect(result.isEmpty()).toEqual(false);
+ });
+ it('should not error when .not().exists() is used on a nested field of a primitive', async () => {
+ const req = { body: { foo: 'hello' } };
+ const result = await body('foo.nop').not().exists().run(req);
+ expect(result.isEmpty()).toEqual(true);
+ });
+ it('should not error when .exists() is used on a nested field of a primitive using wildcard', async () => {
+ const req = { body: { foo: 'hello' } };
+ const result = await body('foo.*.nop').exists().run(req);
+ expect(result.isEmpty()).toEqual(true);
+ });
+});

src/field-selection.spec.ts

@@ -19,14 +19,16 @@ describe('selectFields()', () => {
  const instances = selectFields(req, ['foo', 'baz'], ['cookies']);
 
  expect(instances).toHaveLength(2);
- expect(instances[0]).toMatchObject({
+ expect(instances[0]).toEqual({
  location: 'cookies',
  path: 'foo',
+ originalPath: 'foo',
  value: 'bar',
  });
- expect(instances[1]).toMatchObject({
+ expect(instances[1]).toEqual({
  location: 'cookies',
  path: 'baz',
+ originalPath: 'baz',
  value: 'qux',
  });
  });
@@ -113,14 +115,19 @@ describe('selectFields()', () => {
  const req = {
  query: { foo: ['bar', 'baz'] },
  };
- const instances = selectFields(req, ['foo[1]'], ['query']);
+ const instances = selectFields(req, ['foo[1]', 'foo[2]'], ['query']);
 
- expect(instances).toHaveLength(1);
+ expect(instances).toHaveLength(2);
  expect(instances[0]).toMatchObject({
  location: 'query',
  path: 'foo[1]',
  value: 'baz',
  });
+ expect(instances[1]).toMatchObject({
+ location: 'query',
+ path: 'foo[2]',
+ value: undefined,
+ });
  });
 
  it('selects from headers using lowercase', () => {
@@ -154,7 +161,7 @@ describe('selectFields()', () => {
  });
 
  it('selects inexistent properties', () => {
- const instances = selectFields({}, ['foo.bar.baz'], ['cookies']);
+ const instances = selectFields({ cookies: {} }, ['foo.bar.baz'], ['cookies']);
 
  expect(instances).toHaveLength(1);
  expect(instances[0]).toEqual({
@@ -165,14 +172,24 @@ describe('selectFields()', () => {
  });
  });
 
- it('does not select properties of primitives', () => {
+ it('selects properties of primitives', () => {
  const req = {
  body: { foo: 1 },
  };
- const instances = selectFields(req, ['foo.toFixed'], ['body']);
- expect(instances).toHaveLength(0);
- });
+ const instances = selectFields(req, ['foo.toFixed', 'foo.nop'], ['body']);
 
+ expect(instances).toHaveLength(2);
+ expect(instances[0]).toMatchObject({
+ location: 'body',
+ path: 'foo.toFixed',
+ value: expect.any(Function),
+ });
+ expect(instances[1]).toMatchObject({
+ location: 'body',
+ path: 'foo.nop',
+ value: undefined,
+ });
+ });
  it('deduplicates field instances', () => {
  const req = {
  body: {

src/field-selection.ts

@@ -52,13 +52,19 @@ function expandPath(object: any, path: string | string[], currPath: readonly str
  const rest = segments.slice(1);
 
  if (object != null && !_.isObjectLike(object)) {
- if (key === '**' && !rest.length) {
- // globstar leaves are always selected
- return [reconstructFieldPath(currPath)];
+ if (key === '**') {
+ if (!rest.length) {
+ // globstar leaves are always selected
+ return [reconstructFieldPath(currPath)];
+ }
+ return [];
  }
-
- // there still are paths to traverse, but value is a primitive, stop
- return [];
+ if (key === '*') {
+ // wildcard position does not exist
+ return [];
+ }
+ // value is a primitive, there are still still paths to traverse that will be likely undefined, we return the entire path
+ return [reconstructFieldPath([...currPath, ...segments])];
  }
 
  // Use a non-null value so that inexistent fields are still selected