From 48405b4da0b6a204975d8514fe92f5d2dc270edb Mon Sep 17 00:00:00 2001
From: Philip Le Riche <7701190+p-leriche@users.noreply.github.com>
Date: Wed, 25 Feb 2026 21:44:06 +0000
Subject: [PATCH] Add tests for Modular Inverse operation

---
 tests/operations/tests/ModularInverse.mjs | 78 +++++++++++++++++++++++
 1 file changed, 78 insertions(+)
 create mode 100644 tests/operations/tests/ModularInverse.mjs

diff --git a/tests/operations/tests/ModularInverse.mjs b/tests/operations/tests/ModularInverse.mjs
new file mode 100644
index 00000000..49398c85
--- /dev/null
+++ b/tests/operations/tests/ModularInverse.mjs
@@ -0,0 +1,78 @@
+/**
+ * Modular Inverse tests.
+ *
+ * @author p-leriche [philip.leriche@cantab.net]
+ *
+ * @copyright Crown Copyright 2025
+ * @license Apache-2.0
+ */
+import TestRegister from "../../lib/TestRegister.mjs";
+
+TestRegister.addTests([
+    {
+        name: "Modular Inverse: basic example (3 mod 11)",
+        input: "",
+        expectedOutput: "4",
+        recipeConfig: [
+            {
+                op: "Modular Inverse",
+                args: ["3", "11"],
+            },
+        ],
+    },
+    {
+        name: "Modular Inverse: another coprime pair (7 mod 26)",
+        input: "",
+        expectedOutput: "15",
+        recipeConfig: [
+            {
+                op: "Modular Inverse",
+                args: ["7", "26"],
+            },
+        ],
+    },
+    {
+        name: "Modular Inverse: hexadecimal input (0x10 mod 0x11)",
+        input: "",
+        expectedOutput: "16",
+        recipeConfig: [
+            {
+                op: "Modular Inverse",
+                args: ["0x10", "0x11"],
+            },
+        ],
+    },
+    {
+        name: "Modular Inverse: using input field for value",
+        input: "5",
+        expectedOutput: "21",
+        recipeConfig: [
+            {
+                op: "Modular Inverse",
+                args: ["", "26"],
+            },
+        ],
+    },
+    {
+        name: "Modular Inverse: using input field for modulus",
+        input: "17",
+        expectedOutput: "38",
+        recipeConfig: [
+            {
+                op: "Modular Inverse",
+                args: ["5", ""],
+            },
+        ],
+    },
+    {
+        name: "Modular Inverse: large number (RSA-like)",
+        input: "",
+        expectedOutput: "4969696969697",
+        recipeConfig: [
+            {
+                op: "Modular Inverse",
+                args: ["65537", "9999999999999"],
+            },
+        ],
+    },
+]);