[🤖] Add Unit-Tests

langext/rand_test.go

@@ -0,0 +1,34 @@
+package langext
+
+import (
+	"git.blackforestbytes.com/BlackForestBytes/goext/tst"
+	"testing"
+)
+
+func TestRandBytesLength(t *testing.T) {
+	for _, sz := range []int{0, 1, 16, 32, 1024} {
+		b := RandBytes(sz)
+		tst.AssertEqual(t, len(b), sz)
+	}
+}
+
+func TestRandBytesDistinct(t *testing.T) {
+	a := RandBytes(32)
+	b := RandBytes(32)
+
+	// Two cryptographic random sequences should not be equal in 32 bytes.
+	if len(a) != 32 || len(b) != 32 {
+		t.Fatalf("unexpected length")
+	}
+
+	equal := true
+	for i := range a {
+		if a[i] != b[i] {
+			equal = false
+			break
+		}
+	}
+	if equal {
+		t.Errorf("two consecutive 32-byte RandBytes calls returned identical results")
+	}
+}