jest-isa.js

commit eb22f10eb8126c1ec745e385be14a6f7397dd8c3
Author: Robin Bron <finwo@pm.me>
Date:   Fri,  9 Oct 2020 12:03:01 +0200

Move into it's own git repo

Diffstat:
A
index.js
 | 
31
+++++++++++++++++++++++++++++++
A
package.json
 | 
11
+++++++++++

2 files changed, 42 insertions(+), 0 deletions(-)
diff --git a/index.js b/index.js
@@ -0,0 +1,31 @@
+module.exports = {
+  isA: function (actual, expected) {
+    const result = {
+      message: () => `Expected ${actual} to be a ${expected.name}`,
+      pass   : false
+    };
+    switch (expected) {
+      case Object:
+        result.pass = (!!actual) && ('object' === typeof actual);
+        return result;
+      case Function:
+      case Number:
+      case String:
+        if ('object' === typeof actual) {
+          result.pass = actual instanceof expected;
+          return result;
+        } else {
+          result.pass = expected.name.toLowerCase() === typeof actual;
+          return result;
+        }
+      default:
+        if ('function' === typeof expected['is' + expected.name]) {
+          result.pass = expected['is' + expected.name](actual);
+          return result;
+        } else {
+          result.pass = actual instanceof expected;
+          return result;
+        }
+    }
+  }
+};
diff --git a/package.json b/package.json
@@ -0,0 +1,11 @@
+{
+  "name": "jest-isa",
+  "version": "0.0.4",
+  "description": "",
+  "main": "index.js",
+  "scripts": {
+    "test": "echo \"Error: no test specified\" && exit 1"
+  },
+  "author": "Robin Bron <robin@finwo.nl>",
+  "license": "MIT"
+}