From: Chris Duncan <chris@codecow.com>
Date: Mon, 3 Aug 2026 18:50:08 +0000 (-0700)
Subject: Fix unit conversion to work with readonly unit object.
X-Git-Url: https://git.codecow.com/?a=commitdiff_plain;h=b5765f2bb952540c6a49ab52974210661452b2ad;p=libnemo.git

Fix unit conversion to work with readonly unit object.
---

diff --git a/src/lib/tools.ts b/src/lib/tools.ts
index 9c8e28e..b3e4b5b 100644
--- a/src/lib/tools.ts
+++ b/src/lib/tools.ts
@@ -37,22 +37,19 @@ export function convert (amount: unknown, inputUnit: unknown, outputUnit: unknow
 	if (typeof inputUnit !== 'string') {
 		throw new TypeError('Invalid input unit', { cause: typeof inputUnit })
 	}
-	(inputUnit as string) = inputUnit.toUpperCase()
 	if (typeof outputUnit !== 'string') {
 		throw new TypeError('Invalid output unit', { cause: typeof outputUnit })
 	}
-	(outputUnit as string) = outputUnit.toUpperCase()
-	if (UNITS[inputUnit] == null) {
-		throw new Error(`Unknown denomination ${inputUnit}, expected one of the following: ${Object.keys(UNITS)}`)
-	}
-	if (UNITS[outputUnit] == null) {
-		throw new Error(`Unknown denomination ${outputUnit}, expected one of the following: ${Object.keys(UNITS)}`)
-	}
 	if (format !== undefined && format !== 'bigint' && format !== 'number' && format !== 'string') {
 		throw new Error('Invalid output format', { cause: format })
 	}
+	inputUnit = inputUnit.toUpperCase()
+	outputUnit = outputUnit.toUpperCase()
 
-	const inUnit = UNITS[inputUnit]
+	const inUnit = UNITS[inputUnit as keyof typeof UNITS]
+	if (inUnit == null) {
+		throw new Error(`Unknown denomination ${inputUnit}, expected one of the following: ${Object.keys(UNITS)}`)
+	}
 	let [i, f] = typeof amount === 'string'
 		? amount.split('.')
 		: dec.toString(amount).split('.')
@@ -79,7 +76,10 @@ export function convert (amount: unknown, inputUnit: unknown, outputUnit: unknow
 	}
 
 	// convert to desired denomination
-	const outUnit = UNITS[outputUnit]
+	const outUnit = UNITS[outputUnit as keyof typeof UNITS]
+	if (outUnit == null) {
+		throw new Error(`Unknown denomination ${outputUnit}, expected one of the following: ${Object.keys(UNITS)}`)
+	}
 	i = dec.toString(int, 40)
 	f = i.slice(40 - outUnit).replace(/0*$/g, '')
 	i = i.slice(0, 40 - outUnit).replace(/^0*/g, '')