[PM-2132] Move all specs to the src directory (#5367)

libs/common/spec/matchers/to-equal-buffer.ts

@@ -0,0 +1,34 @@
+/**
+ * The inbuilt toEqual() matcher will always return TRUE when provided with 2 ArrayBuffers.
+ * This is because an ArrayBuffer must be wrapped in a new Uint8Array to be accessible.
+ * This custom matcher will automatically instantiate a new Uint8Array on the received value
+ * (and optionally, the expected value) and then call toEqual() on the resulting Uint8Arrays.
+ */
+export const toEqualBuffer: jest.CustomMatcher = function (
+  received: ArrayBuffer,
+  expected: Uint8Array | ArrayBuffer
+) {
+  received = new Uint8Array(received);
+
+  if (expected instanceof ArrayBuffer) {
+    expected = new Uint8Array(expected);
+  }
+
+  if (this.equals(received, expected)) {
+    return {
+      message: () => `expected
+${received}
+not to match
+${expected}`,
+      pass: true,
+    };
+  }
+
+  return {
+    message: () => `expected
+${received}
+to match
+${expected}`,
+    pass: false,
+  };
+};