Add strict types

Author: wooorm

index.js

@@ -24,6 +24,7 @@ export function toJson(value, options = {}) {
   const comments = comment ? (Array.isArray(comment) ? comment : [comment]) : []
   const delimiter = options.delimiter || ':'
   const forgiving = options.forgiving
+  /** @type {Record<string, unknown>} */
   const propertyOrValues = {}
 
   const lines = value
@@ -46,6 +47,7 @@ export function toJson(value, options = {}) {
     // Transform `value` to a property--value tuple.
     function (value) {
       const values = value.split(delimiter)
+      // @ts-expect-error: always one.
       const result = [values.shift().trim()]
 
       if (values.length > 0) {
@@ -56,7 +58,7 @@ export function toJson(value, options = {}) {
     }
   )
 
-  /** @type {boolean} */
+  /** @type {boolean|undefined} */
   let isPropertyValuePair
 
   for (const [index, line] of pairs.entries()) {
@@ -126,5 +128,6 @@ export function toJson(value, options = {}) {
  * @param {Array<string>} b
  */
 function sortOnFirstIndex(a, b) {
+  // @ts-expect-error: never empty
   return a[0].codePointAt(0) - b[0].codePointAt(0)
 }

test.js

@@ -173,7 +173,7 @@ test('Invalid lists', function (t) {
 
   t.test('should honour `log: false`', function (st) {
     const stop = cept(console, 'log', hoist)
-    /** @type {Array<unknown>} */
+    /** @type {Array<unknown>|undefined} */
     let parameters
 
     toJson('unicorn\nrainbow\nunicorn', {forgiving: true, log: false})
@@ -229,7 +229,7 @@ test('Invalid objects', function (t) {
 
   t.test('should honour `log: false`', function (st) {
     const stop = cept(console, 'log', hoist)
-    /** @type {Array<unknown>} */
+    /** @type {Array<unknown>|undefined} */
     let parameters
 
     toJson('doge: so scare\nunicorn: magic creature\ndoge: so scare\n', {

tsconfig.json

@@ -1,15 +1,17 @@
 {
-  "include": ["*.js"],
+  "include": ["**/**.js"],
+  "exclude": ["coverage", "node_modules"],
   "compilerOptions": {
-    "target": "ES2020",
-    "lib": ["ES2020"],
-    "module": "ES2020",
-    "moduleResolution": "node",
-    "allowJs": true,
     "checkJs": true,
     "declaration": true,
     "emitDeclarationOnly": true,
-    "allowSyntheticDefaultImports": true,
-    "skipLibCheck": true
+    "exactOptionalPropertyTypes": true,
+    "forceConsistentCasingInFileNames": true,
+    "lib": ["es2020"],
+    "module": "node16",
+    "newLine": "lf",
+    "skipLibCheck": true,
+    "strict": true,
+    "target": "es2020"
   }
 }