errcheck

errcheck is a static analysis tool for the Go programming language. Its primary function is to detect unhandled errors in Go code. Static analysis tools examine code without executing it, identifying potential problems before runtime. errcheck focuses specifically on the common Go idiom of returning errors from functions.

The tool works by scanning Go source files and identifying function calls that return error values. It then checks if these returned error values are subsequently checked by the programmer. If a returned error is ignored (e.g., assigned to the blank identifier `_`), errcheck will report it as a potential issue. This helps developers catch bugs where errors might be silently ignored, leading to unexpected program behavior.

errcheck can be integrated into development workflows and continuous integration systems. Its usage typically involves running the `errcheck` command on a Go project's source code. The output will list lines of code where errors appear to be unhandled, along with the specific function call. While errcheck is a valuable tool for improving code quality and robustness, it's important to note that it can sometimes produce false positives, especially in cases where the developer has a specific reason for ignoring an error that errcheck cannot infer. Developers should review the reported issues to determine if they represent actual bugs or intended behavior.