initial commit

package.json

@@ -0,0 +1,12 @@
+{
+  "name": "folktest",
+  "version": "1.0.0",
+  "main": "index.js",
+  "scripts": {
+    "test": "echo \"Error: no test specified\" && exit 1"
+  },
+  "keywords": [],
+  "author": "",
+  "license": "ISC",
+  "description": ""
+}

src/index.js

@@ -0,0 +1,48 @@
+export class AssertionError extends Error {
+    constructor(message) {
+        super(message)
+    }
+}
+
+export const assert = (value, message = `assertion error: ${value} is not true`) => {
+    assertEq(value, true, message)
+}
+
+export const assertEq = (a, b, message = `assertion error: ${a} !== ${b}`) => {
+    if (a === b) {
+        return
+    }
+    else if (Array.isArray(b) && a.length === b.length) {
+        b.forEach((n, i) => assertEq(a[i], n))
+        return
+    } else {
+        throw new AssertionError(message)
+    }
+}
+
+export const assertCallback = () => {
+    let result = false
+    setTimeout(() => assert(result), 0)
+    return () => result = true
+}
+
+export const it = (description, test) => {
+    return () => {
+        try {
+            test()
+
+            return {
+                success: true,
+                description,
+                error: undefined
+            }
+        } catch (error) {
+            return {
+                success: false,
+                description,
+                error
+            }
+        }
+    }
+}
+