Adds Error and Display trait implementation tests.

Signed-off-by: Jesper Brynolf <[email protected]>

Author: Superhepper

tss-esapi/tests/integration_tests/error_tests.rs

@@ -0,0 +1,57 @@
+// Copyright 2023 Contributors to the Parsec project.
+// SPDX-License-Identifier: Apache-2.0
+mod return_code_tests;
+mod wrapper_error_kind_tests;
+
+use std::{convert::TryFrom, error::Error};
+
+use tss_esapi::{
+    constants::tss::{TPM2_RC_INITIALIZE, TSS2_TPM_RC_LAYER},
+    error::{ReturnCode, WrapperErrorKind},
+};
+
+#[test]
+fn test_error_trait_implementation() {
+    // The Error type is only expected to forward everything to the
+    // underlaying error types.
+    let expected_wrapper_error_kind = WrapperErrorKind::InconsistentParams;
+    let wrapper_error = tss_esapi::Error::WrapperError(expected_wrapper_error_kind);
+    let actual_wrapper_error_kind = wrapper_error
+        .source()
+        .expect("`source()` for an Error of type WrapperError returned None.");
+    assert_eq!(
+        format!("{}", expected_wrapper_error_kind),
+        format!("{}", actual_wrapper_error_kind)
+    );
+
+    let expected_return_code = ReturnCode::try_from(TSS2_TPM_RC_LAYER | TPM2_RC_INITIALIZE)
+        .expect("Failed to convert TSS return code into a ReturnCode object.");
+    let tss_error = tss_esapi::Error::TssError(expected_return_code);
+    let actual_return_code = tss_error
+        .source()
+        .expect("`source()` for an Error of type ReturnCode returned None.");
+    assert_eq!(
+        format!("{}", expected_return_code),
+        format!("{}", actual_return_code)
+    );
+}
+
+#[test]
+fn test_display_trait_implementation() {
+    // The Error type is only expected to forward everything to the
+    // underlaying error types.
+    let expected_wrapper_error_kind = WrapperErrorKind::InconsistentParams;
+    let wrapper_error = tss_esapi::Error::WrapperError(expected_wrapper_error_kind);
+    assert_eq!(
+        format!("{}", expected_wrapper_error_kind),
+        format!("{}", wrapper_error)
+    );
+
+    let expected_return_code = ReturnCode::try_from(TSS2_TPM_RC_LAYER | TPM2_RC_INITIALIZE)
+        .expect("Failed to convert TSS return code into a ReturnCode object.");
+    let tss_error = tss_esapi::Error::TssError(expected_return_code);
+    assert_eq!(
+        format!("{}", expected_return_code),
+        format!("{}", tss_error)
+    );
+}