Extended the `UnmarshalString` function in `auth.go` to recognize "auto", "autodiscover", and "autodiscovery" as `SMTPAuthAutoDiscover`. Corresponding test cases were also added to `auth_test.go` to ensure proper functionality.
Refactor the `preferList` definition in `client.go` for improved readability and consistency. This change ensures the code aligns with standard formatting practices.
Refactor the auth type initialization to prevent incorrect assignments and handle empty supported lists. Added comprehensive test cases to verify auto-discovery selection of the strongest authentication method and ensure robustness against empty or invalid input.
Implemented a mechanism to automatically discover and select the strongest supported SMTP authentication type. This feature simplifies the authentication process for users and enhances security by prioritizing stronger mechanisms based on server capabilities. Corresponding tests and documentation have been updated.
Added gosec to the list of enabled linters in `.golangci.toml`. Defined specific exclusion rules to ignore certain false positives and context-specific issues flagged by gosec, ensuring the linter does not impose on intentional code practices.
Changed the SMTP test server base port and updated the corresponding environment variable name to `TEST_BASEPORT_SMTP`. This ensures consistency across the test setup and CI workflow configuration.
In the CI configuration file, the TEST_BASEPORT environment variable was added to various job scopes. This ensures consistency and allows the test base port to be set properly across different OS versions and Go versions.
Moved TestServerPortBase initialization to use an environment variable `TEST_BASEPORT` if provided. This adjustment helps in specifying custom base ports for running tests, ensuring better flexibility in different testing environments.
Structured the initialization of SendError on connection errors to improve code readability and maintainability. This change affects the error handling in both client_120.go and client_119.go by spreading the error details across multiple lines.
Added support for Enhanced Status Codes (ESC) when checking the SMTP client's extensions. The SendError struct now includes the error code and enhanced status code for improved diagnostics.
Previously, only the isTemp flag was considered when aggregating errors. Now, the error code and enhanced status code from the last error are also included. This ensures more comprehensive error reporting and handling.
Added a check for the ENHANCEDSTATUSCODES extension and included error code and enhanced status code information in SendError. This helps in providing more detailed error reporting and troubleshooting.
Renamed `getErrorCode` function to `errorCode` for consistency. Added new tests for the `enhancedStatusCode` function to validate its behavior with various error scenarios.
Renamed `getErrorCode` to `errorCode` and `getEnhancedStatusCode` to `enhancedStatusCode` for consistency. Updated all references in `client.go` and `senderror.go` accordingly, improving readability and maintaining uniformity across the codebase.
Introduce a suite of unit tests for the getErrorCode function to validate its behavior with various error types, including go-mail errors, permanent and temporary errors, wrapper errors, non-4xx/5xx errors, and non-3-digit codes.
Implemented new unit tests for SendError to validate the enhanced status code and error codes in various scenarios, including nil SendError cases, errors with no enhanced status code, and errors with both permanent and temporary error codes. This ensures the correctness of the error handling behavior across different conditions.
Implemented ErrorCode method to retrieve the error code from the server response in SendError. This method distinguishes between server-generated errors and client-generated errors, returning 0 for errors generated by the client.
Updated the TestServerPortBase from 12025 to 30025 to avoid port conflicts with other services running on the common 12025 port. This adjustment aims to ensure that the tests run reliably in diverse environments.
Enhance error handling by adding error code and enhanced status code to the SendError struct. This allows for better troubleshooting and debugging by providing more detailed SMTP server responses.
Revised the documentation for greater clarity: swapped the listed items for explicit and implicit SSL/TLS support, and detailed the supported SMTP authentication mechanisms in an itemized format. This ensures users understand all available options and configurations more clearly.
Updated SPDX identifiers from CC0-1.0 to MIT across multiple files, including `.github`, `CONTRIBUTING.md`, `README.md`, and more. Deleted the `LICENSES/CC0-1.0.txt` file as it is no longer relevant.
Corrected multiple instances of the misspelled "Content-Dispositon" to "Content-Disposition" in the msgwriter_test.go file. This ensures that the error messages in the tests are accurate and improve code readability.
Corrected multiple instances of the word "non-existant" to "non-existent" in test descriptions to improve code clarity and accuracy. This change affects both smtp_test.go and msg_test.go files.
The test name had a typo in the word "recipient." This commit corrects "recepient" to "recipient" to improve code readability and maintain consistency in naming conventions. This change does not modify any functional behavior of the tests.
Moved serverProps outside goroutines to improve code readability and maintainability. Added a RWMutex to serverProps to ensure thread-safe access to EchoBuffer, preventing race conditions during concurrent writes.
Renamed 'err' to 'berr' to avoid shadowing outer variable. This change ensures clearer error handling and avoids potential issues with variable scope and readability in the smtp_test.go file.
Removed JSON logger tests from smtp_test.go and relocated them to a new file smtp_121_test.go, ensuring compliance with Go 1.21. This change maintains test integrity while organizing tests by Go version compatibility.
Removed redundant mutex and streamlined anonymous goroutine syntax for test server setup by passing echoBuffer directly as a parameter. This change reduces unnecessary use of shared resources and simplifies the test code structure and fixes potential race conditions
