includes() method update passed variable type

rawpixel-vincent · Dec 31, 2024 · 240d1ca · 240d1ca
1 parent 30ca21c
commit 240d1ca
Show file tree

Hide file tree

Showing 9 changed files with 1,033 additions and 651 deletions.
diff --git a/README.md b/README.md
@@ -122,6 +122,21 @@ const bothWay = list.withPrefix('data.').withSuffix('.ext');
 /** @type {any|unknown|'notInTheList'} */
 let val;
 list.includes(val); // No type error just boolean result.
+
+if (list.includes(val)) {
+  // val type is now 'foo' | 'bar'
+}
+
+const valKnown = Math.random() > 0.5 ? 'notInTheList' : 'foo';
+// valKnown type is 'foo' | 'notInTheList'
+if (list.includes(valKnown)) {
+  // valKnown type is now 'foo'
+} else if (val !== 'notInTheList') {
+  // valKnown type is now never
+} else {
+  // valKnown type is 'notInTheList'
+}
+
 // similar types fix for indexOf, lastIndexOf, filter, some, every, findIndex and find methods.
 
 // Get a copy of the underlying array -> T[]

diff --git a/package-lock.json b/package-lock.json
diff --git a/package.json b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "string-literal-list",
-  "version": "1.31.0",
+  "version": "1.32.0",
   "description": "an array for string literal",
   "main": "stringList.cjs",
   "files": [

diff --git a/strict.min.cjs b/strict.min.cjs
diff --git a/strict.min.js b/strict.min.js
diff --git a/stringList.cjs b/stringList.cjs
diff --git a/stringList.min.cjs b/stringList.min.cjs
diff --git a/stringList.min.js b/stringList.min.js
diff --git a/types/list.d.ts b/types/list.d.ts
@@ -92,28 +92,6 @@ declare global {
           : never
         : never;
 
-      // withDerivatedSuffix<S extends string>(
-      //   chars: S,
-      // ):
-      //   | T
-      //   | StringLiteralList.string.DropSuffix<
-      //       StringLiteralList.string.DropSuffix<`${T}${S}${S}`, S>,
-      //       `${S}${S}`
-      //     > extends infer W extends string
-      //   ? MaybeReadonly<Mut, IStringList<W, readonly W[], Mut, true>>
-      //   : never;
-
-      // withDerivatedPrefix<S extends string>(
-      //   chars: S,
-      // ):
-      //   | T
-      //   | StringLiteralList.string.DropPrefix<
-      //       StringLiteralList.string.DropPrefix<`${S}${S}${T}`, S>,
-      //       `${S}${S}`
-      //     > extends infer W extends string
-      //   ? MaybeReadonly<Mut, IStringList<W, readonly W[], Mut, true>>
-      //   : never;
-
       withReplace<S extends string, D extends string>(
         searchValue: S,
         replaceValue: D,
@@ -277,7 +255,10 @@ declare global {
       at(n: number): Tuple[number] | undefined;
 
       // Type override to prevent string not in type T issue
-      includes<PP = Tuple[number]>(val: PP, fromIndex?: number): boolean;
+      includes<PP = Tuple[number]>(
+        val: PP | string | null | undefined,
+        fromIndex?: number,
+      ): val is Tuple[number];
       indexOf<PP = Tuple[number]>(
         searchElement: PP,
         fromIndex?: number,