Add parseBool utility function (#39)

Resolves #8

Author: drebrez

CHANGELOG.md

@@ -7,6 +7,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+- added `parseBool` utility function
+
 ## [0.6.0] - 2024-06-26
 
 ### dependabot: \#37 Bump braces from 3.0.2 to 3.0.3

src/lib/boolean.spec.ts

@@ -0,0 +1,42 @@
+import { parseBool } from "./boolean";
+
+describe("boolean tests", () => {
+  test.each([
+    // Test cases like in C#
+    // https://github.com/dotnet/runtime/blob/main/src/libraries/System.Runtime/tests/System.Runtime.Tests/System/BooleanTests.cs
+    [null as unknown as string, false],
+    [undefined as unknown as string, false],
+    [0 as unknown as string, false],
+    [1 as unknown as string, false],
+    [10 as unknown as string, false],
+    [new Date() as unknown as string, false],
+    ["True", true],
+    ["true", true],
+    ["TRUE", true],
+    ["tRuE", true],
+    ["  True  ", true],
+    ["True\0", true],
+    [" \0 \0  True   \0 ", true],
+    ["False", false],
+    ["false", false],
+    ["FALSE", false],
+    ["fAlSe", false],
+    ["False  ", false],
+    ["False\0", false],
+    ["  False \0\0\0  ", false],
+    ["", false],
+    [" ", false],
+    ["Garbage", false],
+    ["True\0Garbage", false],
+    ["True\0True", false],
+    ["True True", false],
+    ["True False", false],
+    ["False True", false],
+    ["Fa lse", false],
+    ["T", false],
+    ["0", false],
+    ["1", false],
+  ])('parseBool("%s")', (value, expected) => {
+    expect(parseBool(value)).toBe(expected);
+  });
+});

src/lib/boolean.ts

@@ -0,0 +1,12 @@
+import { isNullOrEmpty } from "./string";
+
+/**
+ * Converts a string to a boolean
+ * @param value The string to convert
+ * @returns The parsed boolean
+ */
+export function parseBool(value?: string): boolean {
+  // Similar to C# implementation that trims also null characters
+  // https://github.com/dotnet/runtime/blob/main/src/libraries/System.Private.CoreLib/src/System/Boolean.cs#L277
+  return !isNullOrEmpty(value) && value?.replace(/[\s\0]/g, "").toLowerCase() === "true";
+}