Basic Unit Test for Verhoeff (#37195)

* Create basic Unit Test for Verhoff

* Change the build script for Accessor class

* Change structure and remove private accessors

* Change dependencies in build file

* Reduce dependencies list

* Remove empty sources

Editorial commit: remove extra `sources = []`, I expect our templates to handle this one missing.

---------

Co-authored-by: Andrei Litvin <andy314@gmail.com>

Author: tersal

src/BUILD.gn

@@ -66,6 +66,7 @@ if (chip_build_tests) {
       "${chip_root}/src/protocols/interaction_model/tests",
       "${chip_root}/src/protocols/secure_channel/tests",
       "${chip_root}/src/protocols/user_directed_commissioning/tests",
+      "${chip_root}/src/lib/support/verhoeff/tests",
       "${chip_root}/src/system/tests",
       "${chip_root}/src/transport/retransmit/tests",
       "${chip_root}/src/transport/tests",

src/lib/support/verhoeff/tests/BUILD.gn

@@ -0,0 +1,28 @@
+# Copyright (c) 2024 Project CHIP Authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import("//build_overrides/build.gni")
+import("//build_overrides/chip.gni")
+import("//build_overrides/pigweed.gni")
+import("${chip_root}/build/chip/chip_test_suite.gni")
+
+chip_test_suite("tests") {
+  output_name = "libVerhoeffTest"
+
+  test_sources = [ "TestVerhoeff.cpp" ]
+
+  public_deps = [ "${chip_root}/src/lib/support:support" ]
+
+  cflags = [ "-Wconversion" ]
+}

src/lib/support/verhoeff/tests/TestVerhoeff.cpp

@@ -0,0 +1,70 @@
+/*
+ *
+ *    Copyright (c) 2025 Project CHIP Authors
+ *
+ *    Licensed under the Apache License, Version 2.0 (the "License");
+ *    you may not use this file except in compliance with the License.
+ *    You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *    Unless required by applicable law or agreed to in writing, software
+ *    distributed under the License is distributed on an "AS IS" BASIS,
+ *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *    See the License for the specific language governing permissions and
+ *    limitations under the License.
+ */
+
+#include <pw_unit_test/framework.h>
+
+#include <lib/support/verhoeff/Verhoeff.h>
+
+#include <string>
+
+namespace {
+
+TEST(TestVerhoeff, TestVerhoeff)
+{
+
+    // Valid cases
+    EXPECT_EQ(Verhoeff10::ComputeCheckChar("236"), '3');
+    EXPECT_EQ(Verhoeff10::ComputeCheckChar("0"), '4');
+    EXPECT_EQ(Verhoeff10::ComputeCheckChar("11111"), '5');
+
+    EXPECT_TRUE(Verhoeff10::ValidateCheckChar("123451"));
+    EXPECT_TRUE(Verhoeff10::ValidateCheckChar("0987652"));
+    EXPECT_TRUE(Verhoeff10::ValidateCheckChar("150"));
+
+    // Invalid cases
+    EXPECT_NE(Verhoeff10::ComputeCheckChar("236"), '8');
+    EXPECT_NE(Verhoeff10::ComputeCheckChar("0"), '1');
+    EXPECT_NE(Verhoeff10::ComputeCheckChar("11111"), '7');
+
+    EXPECT_FALSE(Verhoeff10::ValidateCheckChar("123456"));
+    EXPECT_FALSE(Verhoeff10::ValidateCheckChar("0987651"));
+    EXPECT_FALSE(Verhoeff10::ValidateCheckChar("157"));
+
+    // Transposition
+    EXPECT_NE(Verhoeff10::ComputeCheckChar("12345"), Verhoeff10::ComputeCheckChar("13245"));
+    EXPECT_NE(Verhoeff10::ComputeCheckChar("1122334455"), Verhoeff10::ComputeCheckChar("1122334545"));
+    EXPECT_NE(Verhoeff10::ComputeCheckChar("1234567890"), Verhoeff10::ComputeCheckChar("1234567809"));
+
+    // Non adjacent transpose
+    EXPECT_NE(Verhoeff10::ComputeCheckChar("12345"), Verhoeff10::ComputeCheckChar("14325"));
+    EXPECT_NE(Verhoeff10::ComputeCheckChar("876543"), Verhoeff10::ComputeCheckChar("678543"));
+
+    // Long numbers
+    EXPECT_EQ(Verhoeff10::ComputeCheckChar("4356678912349008"), '7');
+    EXPECT_EQ(Verhoeff10::ComputeCheckChar("78324562830019274123748"), '4');
+
+    // Invalid character
+    EXPECT_EQ(Verhoeff10::ComputeCheckChar("123F4567"), 0);
+    EXPECT_EQ(Verhoeff10::ComputeCheckChar("0A"), 0);
+    EXPECT_EQ(Verhoeff10::ComputeCheckChar("I"), 0);
+    EXPECT_EQ(Verhoeff10::ComputeCheckChar("23.4"), 0);
+
+    // Empty string
+    EXPECT_EQ(Verhoeff10::ComputeCheckChar(""), '0');
+}
+
+} // namespace