fix(interpreter): ensure regexp correctly works with null & `unde…

…fined` values (#14)

* fix(js/interpreters): prevent regex() from returning true when value is undefined

if key is not defined or if value is undefined, the regex should not evaluate it because it can lead
to false positive.
The undefined type is evaluated as a string 'undefined',\i undefined should be
evaluated with the "exist" operator

* test(js/intepreters.spec): regex: add test for undefined values

Co-authored-by: Jérémy <jeremy.huard@doeo.fr>
Co-authored-by: Sergii <sergiy.stotskiy@gmail.com>

packages/js/spec/interpreters.spec.ts

@@ -353,6 +353,15 @@ describe('Condition Interpreter', () => {
       expect(interpret(condition, item('ucast@github.com'))).to.be.true
       expect(interpret(condition, item('some text'))).to.be.false
     })
+
+    it('return false if key is `undefined` or `null`', () => {
+      const condition = new Field('regex', 'email', /i/)
+
+      expect(interpret(condition, { email: 'ucast@github.com', })).to.be.true
+      expect(interpret(condition, { email: undefined, })).to.be.false
+      expect(interpret(condition, { email: null, })).to.be.false
+      expect(interpret(condition, {})).to.be.false
+    })
   })
 
   describe('where', () => {

packages/js/src/interpreters.ts

@@ -73,7 +73,7 @@ export const exists: Interpret<Field<boolean>> = (node, object, { get }) => {
 };
 
 export const mod = testValueOrArray<[number, number], number>((node, value) => {
-  return value % node.value[0] === node.value[1];
+  return typeof value === 'number' && value % node.value[0] === node.value[1];
 });
 
 export const size: Interpret<Field<number>, AnyObject | unknown[]> = (node, object, { get }) => {
@@ -88,7 +88,9 @@ export const size: Interpret<Field<number>, AnyObject | unknown[]> = (node, obje
     : test(items);
 };
 
-export const regex = testValueOrArray<RegExp, string>((node, value) => node.value.test(value));
+export const regex = testValueOrArray<RegExp, string>((node, value) => {
+  return typeof value === 'string' && node.value.test(value);
+});
 
 export const within = testValueOrArray<unknown[], unknown>((node, object, { equal }) => {
   return includes(node.value, object, equal);