Refactor money formatters in base presenter

app/presenters/base.presenter.js

@@ -116,33 +116,37 @@ function formatLongDateTime (date) {
 }
 
 /**
- * Formats a number which represents a value in pounds as a money string, for example, 1149 as '1149.00'
+ * Formats a value in pence as a money string with commas, for example, 12776805 as '£127,768.05'
+ *
+ * As this is intended for showing values in the UI if the value is a negative it will be made a positive before then
+ * being formatted. This is because the UI shows credits as '£127,768.05 credit' rather than '£-127,768.05'.
+ *
+ * > Credit to https://stackoverflow.com/a/32154217/6117745 for showing numbers with commas
  *
  * @param {Number} value The value to display as currency. Assumed to be in pounds
  * @param {Boolean} includeSymbol Whether to add the £ symbol to the start of the returned string
  *
- * @returns {string} The value formatted as a money string with optional currency symbol
+ * @returns {string} The value formatted as a money string with commas with optional currency symbol
  */
-function formatNumberAsMoney (value, includeSymbol = false) {
-  const symbol = includeSymbol ? '£' : ''
+function formatMoney (valueInPence) {
+  // Even though we store signed values (which you should never do!) we don't display them in the UI. Argh!!!
+  const positiveValueInPence = Math.abs(valueInPence)
+  const positiveValueInPounds = convertPenceToPounds(positiveValueInPence)
 
-  return `${symbol}${value.toFixed(2)}`
+  return `£${positiveValueInPounds.toLocaleString('en-GB', { minimumFractionDigits: 2, maximumFractionDigits: 2 })}`
 }
 
 /**
- * Formats a number which represents a value in pounds as a money string with commas, for example, 2889 as '2,889.00'
+ * Formats a number, which represents a value in pence to pounds, for example, 12776805 as '127768.05'
  *
- * > Credit to https://stackoverflow.com/a/32154217/6117745
+ * @param {*} valueInPence The value to be formatted to pounds
  *
- * @param {Number} value The value to display as currency. Assumed to be in pounds
- * @param {Boolean} includeSymbol Whether to add the £ symbol to the start of the returned string
- *
- * @returns {string} The value formatted as a money string with commas with optional currency symbol
+ * @returns {string} The value converted to pounds and formatted to two decimal places
  */
-function formatNumberAsMoneyWithCommas (value, includeSymbol = false) {
-  const symbol = includeSymbol ? '£' : ''
+function formatPounds (valueInPence) {
+  const valueInPounds = convertPenceToPounds(valueInPence)
 
-  return `${symbol}${value.toLocaleString('en-GB', { minimumFractionDigits: 2 })}`
+  return valueInPounds.toFixed(2)
 }
 
 /**
@@ -167,7 +171,7 @@ module.exports = {
   formatChargingModuleDate,
   formatLongDate,
   formatLongDateTime,
-  formatNumberAsMoney,
-  formatNumberAsMoneyWithCommas,
+  formatMoney,
+  formatPounds,
   leftPadZeroes
 }

app/presenters/data/mock-bill-run.presenter.js

@@ -5,7 +5,7 @@
  * @module MockBillRunPresenter
  */
 
-const { convertPenceToPounds, formatAbstractionPeriod, formatLongDate, formatNumberAsMoney } = require('../base.presenter.js')
+const { formatAbstractionPeriod, formatLongDate, formatPounds } = require('../base.presenter.js')
 
 function go (billRun) {
   const {
@@ -31,7 +31,7 @@ function go (billRun) {
     transactionFile,
     billRunNumber,
     financialYear: `${fromFinancialYearEnding} to ${toFinancialYearEnding}`,
-    debit: formatNumberAsMoney(convertPenceToPounds(netTotal)),
+    debit: formatPounds(netTotal),
     bills: _formatBills(bills)
   }
 }
@@ -42,8 +42,8 @@ function _formatAdditionalCharges (transaction) {
   const { grossValuesCalculated, isWaterCompanyCharge, supportedSourceName } = transaction
 
   if (supportedSourceName) {
-    const formattedSupportedSourceCharge = formatNumberAsMoney(grossValuesCalculated.supportedSourceCharge, true)
-    formattedData.push(`Supported source ${supportedSourceName} (${formattedSupportedSourceCharge})`)
+    const formattedSupportedSourceCharge = formatPounds(grossValuesCalculated.supportedSourceCharge * 100, true)
+    formattedData.push(`Supported source ${supportedSourceName} (£${formattedSupportedSourceCharge})`)
   }
 
   if (isWaterCompanyCharge) {
@@ -110,9 +110,9 @@ function _formatBills (bills) {
       accountAddress,
       contact,
       isWaterCompany: billLicences[0].licence.isWaterUndertaker,
-      credit: formatNumberAsMoney(convertPenceToPounds(creditNoteValue)),
-      debit: formatNumberAsMoney(convertPenceToPounds(invoiceValue)),
-      netTotal: formatNumberAsMoney(convertPenceToPounds(netAmount)),
+      credit: formatPounds(creditNoteValue),
+      debit: formatPounds(invoiceValue),
+      netTotal: formatPounds(netAmount),
       licences: _formatBillLicences(billLicences)
     }
   })
@@ -135,9 +135,9 @@ function _formatBillLicences (billLicences) {
       licence,
       licenceStartDate: billLicence.licence.startDate,
       licenceHolder,
-      credit: formatNumberAsMoney(convertPenceToPounds(credit)),
-      debit: formatNumberAsMoney(convertPenceToPounds(debit)),
-      netTotal: formatNumberAsMoney(convertPenceToPounds(netTotal)),
+      credit: formatPounds(credit),
+      debit: formatPounds(debit),
+      netTotal: formatPounds(netTotal),
       transactions: _formatTransactions(transactions)
     }
   })
@@ -167,10 +167,10 @@ function _formatTransactions (transactions) {
       billableDays,
       authorisedDays,
       chargeQuantity,
-      credit: isCredit ? formatNumberAsMoney(convertPenceToPounds(netAmount)) : '0.00',
-      debit: isCredit ? '0.00' : formatNumberAsMoney(convertPenceToPounds(netAmount)),
+      credit: isCredit ? formatPounds(netAmount) : '0.00',
+      debit: isCredit ? '0.00' : formatPounds(netAmount),
       chargePeriod: `${formatLongDate(startDate)} to ${formatLongDate(endDate)}`,
-      chargeRefNumber: `${chargeCategoryCode} (${formatNumberAsMoney(grossValuesCalculated.baselineCharge, true)})`,
+      chargeRefNumber: `${chargeCategoryCode} (£${formatPounds(grossValuesCalculated.baselineCharge * 100, true)})`,
       chargeDescription,
       addCharges: _formatAdditionalCharges(transaction),
       adjustments: _formatAdjustments(chargeReference),

test/presenters/base.presenter.test.js

@@ -166,40 +166,34 @@ describe('Base presenter', () => {
     })
   })
 
-  describe('#formatNumberAsMoney()', () => {
-    const valueInPounds = 1149.5
+  describe('#formatPounds()', () => {
+    const valueInPence = 114950
 
-    describe('when no £ symbol is requested', () => {
-      it('correctly returns the value as a money string with no symbol, for example, 1149.50', async () => {
-        const result = BasePresenter.formatNumberAsMoney(valueInPounds)
+    it('correctly returns the value as pounds, for example, 1149.50', async () => {
+      const result = BasePresenter.formatPounds(valueInPence)
 
-        expect(result).to.equal('1149.50')
-      })
+      expect(result).to.equal('1149.50')
     })
+  })
 
-    describe('when the £ symbol is requested', () => {
-      it('correctly returns the value as a money string with a symbol, for example, £1149.50', async () => {
-        const result = BasePresenter.formatNumberAsMoney(valueInPounds, true)
+  describe('#formatMoney()', () => {
+    let valueInPence
 
-        expect(result).to.equal('£1149.50')
+    describe('when the value in pence is positive', () => {
+      beforeEach(() => {
+        valueInPence = 114950
       })
-    })
-  })
-
-  describe('#formatNumberAsMoneyWithCommas()', () => {
-    const valueInPounds = 1149.5
 
-    describe('when no £ symbol is requested', () => {
-      it('correctly returns the value as a money string with commas and no symbol, for example, 1,149.50', async () => {
-        const result = BasePresenter.formatNumberAsMoneyWithCommas(valueInPounds)
+      it('correctly returns the value as a money string with commas and a symbol, for example, £1,149.50', async () => {
+        const result = BasePresenter.formatMoney(valueInPence)
 
-        expect(result).to.equal('1,149.50')
+        expect(result).to.equal('£1,149.50')
       })
     })
 
-    describe('when the £ symbol is requested', () => {
-      it('correctly returns the value as a money string with commas and a symbol, for example, £1,149.50', async () => {
-        const result = BasePresenter.formatNumberAsMoneyWithCommas(valueInPounds, true)
+    describe('when the value in pence is negative', () => {
+      it('correctly returns the value as a positive money string with commas and a symbol, for example, £1,149.50', async () => {
+        const result = BasePresenter.formatMoney(valueInPence, true)
 
         expect(result).to.equal('£1,149.50')
       })