From 3915cf2dda0e591acf84d2ef7419476ceea72b05 Mon Sep 17 00:00:00 2001
From: djmil <andriy@djmil.dev>
Date: Thu, 11 Jun 2026 19:10:08 +0000
Subject: [PATCH] pkg/check: NotEqual, DeepEqual, ElementsMatch

---
 pkg/check/check.go | 39 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 39 insertions(+)

diff --git a/pkg/check/check.go b/pkg/check/check.go
index 0f4bdbb..6f6e798 100644
--- a/pkg/check/check.go
+++ b/pkg/check/check.go
@@ -9,6 +9,7 @@
 package check
 
 import (
+	"reflect"
 	"strings"
 	"testing"
 
@@ -71,6 +72,44 @@ func Equal[T comparable](t *testing.T, got, want T) {
 	}
 }
 
+// NotEqual fails the test if got == want.
+func NotEqual[T comparable](t *testing.T, got, want T) {
+	t.Helper()
+	if got == want {
+		t.Errorf("expected values to differ, got %v", got)
+	}
+}
+
+// DeepEqual fails the test if got and want are not deeply equal.
+// Use instead of Equal for maps, slices, and structs with slice fields.
+func DeepEqual(t *testing.T, got, want any) {
+	t.Helper()
+	if !reflect.DeepEqual(got, want) {
+		t.Errorf("got %v, want %v", got, want)
+	}
+}
+
+// ElementsMatch fails the test if got and want do not contain the same
+// elements regardless of order, including duplicates. T must be comparable —
+// for slices or maps as elements, use DeepEqual after sorting manually.
+func ElementsMatch[T comparable](t *testing.T, got, want []T) {
+	t.Helper()
+	if len(got) != len(want) {
+		t.Errorf("length mismatch: got %d elements, want %d", len(got), len(want))
+		return
+	}
+	freq := make(map[T]int, len(want))
+	for _, v := range want {
+		freq[v]++
+	}
+	for _, v := range got {
+		if freq[v]--; freq[v] < 0 {
+			t.Errorf("unexpected element: %v", v)
+			return
+		}
+	}
+}
+
 // Ok fails the test if r holds an error, then returns the value.
 func Ok[T any](t *testing.T, r result.Expect[T]) T {
 	t.Helper()