fix(fee-randomization): fix fee range in PaymentConfirmModal

src/components/PaymentConfirmModal.tsx

@@ -11,6 +11,13 @@ import { AmountSats } from '../libs/JmWalletApi'
 import { jarInitial } from './jars/Jar'
 import { isValidNumber } from '../utils'
 
+const feeRange: (feeValues: FeeValues) => [number, number] = (feeValues) => {
+  const feeTargetInSatsPerVByte = feeValues.tx_fees! / 1_000
+  const minFeeSatsPerVByte = Math.max(1, feeTargetInSatsPerVByte)
+  const maxFeeSatsPerVByte = feeTargetInSatsPerVByte * (1 + feeValues.tx_fees_factor!)
+  return [minFeeSatsPerVByte, maxFeeSatsPerVByte]
+}
+
 const useMiningFeeText = ({ feeConfigValues }: { feeConfigValues?: FeeValues }) => {
   const { t } = useTranslation()
 
@@ -24,24 +31,23 @@ const useMiningFeeText = ({ feeConfigValues }: { feeConfigValues?: FeeValues })
     } else if (unit === 'blocks') {
       return t('send.confirm_send_modal.text_miner_fee_in_targeted_blocks', { count: feeConfigValues.tx_fees })
     } else {
-      const feeTargetInSatsPerVByte = feeConfigValues.tx_fees! / 1_000
-      if (feeConfigValues.tx_fees_factor === 0) {
+      const [minFeeSatsPerVByte, maxFeeSatsPerVByte] = feeRange(feeConfigValues)
+      const fractionDigits = 2
+
+      if (minFeeSatsPerVByte.toFixed(fractionDigits) === maxFeeSatsPerVByte.toFixed(fractionDigits)) {
         return t('send.confirm_send_modal.text_miner_fee_in_satspervbyte_exact', {
-          value: feeTargetInSatsPerVByte.toLocaleString(undefined, {
+          value: minFeeSatsPerVByte.toLocaleString(undefined, {
             maximumFractionDigits: Math.log10(1_000),
           }),
         })
       }
 
-      const minFeeSatsPerVByte = Math.max(1, feeTargetInSatsPerVByte * (1 - feeConfigValues.tx_fees_factor!))
-      const maxFeeSatsPerVByte = feeTargetInSatsPerVByte * (1 + feeConfigValues.tx_fees_factor!)
-
       return t('send.confirm_send_modal.text_miner_fee_in_satspervbyte_randomized', {
         min: minFeeSatsPerVByte.toLocaleString(undefined, {
-          maximumFractionDigits: 1,
+          maximumFractionDigits: fractionDigits,
         }),
         max: maxFeeSatsPerVByte.toLocaleString(undefined, {
-          maximumFractionDigits: 1,
+          maximumFractionDigits: fractionDigits,
         }),
       })
     }

src/components/settings/FeeConfigModal.tsx

@@ -278,7 +278,7 @@ const FeeConfigForm = forwardRef(
                           : '',
                       })}
                     </rb.Form.Label>
-                    <rb.Form.Text>{t('settings.fees.description_tx_fees_factor')}</rb.Form.Text>
+                    <rb.Form.Text>{t('settings.fees.description_tx_fees_factor_^0.9.10')}</rb.Form.Text>
                     <rb.InputGroup hasValidation>
                       <rb.InputGroup.Text id="txFeesFactor-addon1" className={styles.inputGroupText}>
                         %

src/i18n/locales/en/translation.json

@@ -239,7 +239,7 @@
       "feedback_invalid_tx_fees_blocks": "Please provide a valid block target between {{ min }} and {{ max }}.",
       "feedback_invalid_tx_fees_satspervbyte": "Please provide a valid transaction fee in sats/vByte between {{ min }} and {{ max }}.",
       "label_tx_fees_factor": "Fee randomization",
-      "description_tx_fees_factor": "Random fees improve privacy. The percentage is to be understood as a +/- around the base fee. Example: If you set the base fee to 10 sats/vByte and the randomization to 30%, a value between 7 and 13 sats/vByte will be used. Default: 20%.",
+      "description_tx_fees_factor_^0.9.10": "Random fees improve privacy. The percentage is an upward randomization factor of the base fee. Example: If you set the base fee to 10 sats/vByte and the randomization to 30%, a value between 10 and 13 sats/vByte will be used. Default: 20%.",
       "feedback_invalid_tx_fees_factor": "Please provide a valid fee randomization value between {{ min }} and {{ max }}.",
       "title_max_cj_fee_settings": "Collaborator fees",
       "description_max_cj_fee_settings": "Collaborator fees relate to liquidity price and depend on market conditions. Total fees paid for each transaction depend on the amount of collaborators. Additional collaborators increase privacy, but also fees.",