backend barebone done, big chunk of work done

server/internal/auth/password_test.go

@@ -0,0 +1,49 @@
+// Package auth_test tests password hashing and verification.
+package auth_test
+
+import (
+	"testing"
+
+	"messenger/internal/auth"
+)
+
+func TestHashAndVerify(t *testing.T) {
+	pwd := "secret"
+	hash, err := auth.HashPassword(pwd)
+	if err != nil {
+		t.Fatalf("HashPassword error: %v", err)
+	}
+	ok, err := auth.VerifyPassword(hash, pwd)
+	if err != nil {
+		t.Fatalf("VerifyPassword error: %v", err)
+	}
+	if !ok {
+		t.Fatal("expected password to verify")
+	}
+}
+
+func TestWrongPassword(t *testing.T) {
+	hash, _ := auth.HashPassword("correct")
+	ok, err := auth.VerifyPassword(hash, "wrong")
+	if err != nil {
+		t.Fatalf("VerifyPassword error on wrong password: %v", err)
+	}
+	if ok {
+		t.Fatal("wrong password should not verify")
+	}
+}
+
+func TestInvalidHashFormat(t *testing.T) {
+	_, err := auth.VerifyPassword("invalidformat", "pwd")
+	if err == nil {
+		t.Fatal("expected error on invalid hash format")
+	}
+}
+
+func TestDifferentSalts(t *testing.T) {
+	h1, _ := auth.HashPassword("pass")
+	h2, _ := auth.HashPassword("pass")
+	if h1 == h2 {
+		t.Fatal("expected different hashes for same password due to salt")
+	}
+}