going dependencyless

Author: Adam McKee

lib/expression.ts

@@ -1,5 +1,4 @@
 import { readFile } from 'node:fs/promises'
-import MagicString from 'magic-string'
 
 type TemplateExpression = {
     index: number
@@ -23,15 +22,18 @@ export async function evalTemplateExpressions(
     if (!expressions.length) {
         return content
     }
-    const ms = new MagicString(content)
+    let offset = 0
     for (const expression of expressions) {
-        ms.update(
-            expression.index,
-            expression.index + expression.outie.length,
-            await evaluate(expression.innie),
-        )
+        const expressionResult = await evaluate(expression.innie)
+        content =
+            content.substring(0, expression.index + offset) +
+            expressionResult +
+            content.substring(
+                expression.index + expression.outie.length + offset,
+            )
+        offset += expressionResult.length - expression.outie.length
     }
-    return ms.toString()
+    return content
 }
 
 async function evaluate(expression: string): Promise<string> {

package.json

@@ -37,13 +37,10 @@
     "test": "node --test \"lib/**/*.spec.ts\"",
     "typecheck": "tsc --noEmit"
   },
-  "dependencies": {
-    "magic-string": "0.30.17"
-  },
   "devDependencies": {
-    "@types/node": "^22.14.1",
-    "prettier": "^3.5.3",
-    "typescript": "5.8.2"
+    "@types/node": "^25.3.0",
+    "prettier": "^3.8.1",
+    "typescript": "5.9.3"
   },
   "files": [
     "lib/*",