feat[2020-day-02]: find the number of valid passwords

Solution for part 1

Author: developher-net

2020/day-02/cleanupPasswords.js

@@ -27,7 +27,7 @@ const splitRule = (rule) => {
 /**
  * Validates a password against the specified rule
  */
-const isValid = (rule, password) => {
+const isValidPassword = (rule, password) => {
   // count how many times `rule.char` exists in `password`
   const count = (
     password.match(
@@ -40,8 +40,15 @@ const isValid = (rule, password) => {
   return true
 }
 
+const isValidRecord = (record) => {
+  const { rule, password } = splitRecord(record)
+  const { min, max, char } = splitRule(rule)
+  return isValidPassword({ min, max, char }, password)
+}
+
 module.exports = {
   splitRecord,
   splitRule,
-  isValid
+  isValidRecord,
+  isValidPassword
 }

2020/day-02/cleanupPasswords.test.js

@@ -1,6 +1,6 @@
 /* eslint-env mocha */
 const { expect } = require('chai')
-const { splitRecord, splitRule, isValid } = require('./cleanupPasswords')
+const { splitRecord, splitRule, isValidPassword, isValidRecord } = require('./cleanupPasswords')
 
 const testData = [
   '1-3 a: abcde',
@@ -27,13 +27,27 @@ describe('--- Day 2: Password Philosophy ---', () => {
         })
       })
     })
-    describe('isValid()', () => {
+    describe('isValidPassword()', () => {
       it('checks if a specified password matches the specified rule', () => {
         const expectedResults = [true, false, true]
         testData.forEach((row, idx) => {
           const { rule, password } = splitRecord(row)
           const { min, max, char } = splitRule(rule)
-          expect(isValid({ min, max, char }, password))
+          expect(isValidPassword({ min, max, char }, password))
+            .to.equal(expectedResults[idx])
+        })
+      })
+      it('won\'t allow more than the specified character count', () => {
+        const badPass = 'abcabcabcabc'
+        expect(isValidPassword({ min: 2, max: 3, char: 'a' }, badPass))
+          .to.equal(false)
+      })
+    })
+    describe('isValidRecord()', () => {
+      it('checks if a specified record contains valid rule and password', () => {
+        const expectedResults = [true, false, true]
+        testData.forEach((row, idx) => {
+          expect(isValidRecord(row))
             .to.equal(expectedResults[idx])
         })
       })