Added a unique exit code for failed tests, added generic way to bubbl…

…e up errors with exit codes from cmd, organized exit code definitions into one package (#301)

Co-authored-by: anishnaik <[email protected]>

cmd/exitcodes/error_with_exit_code.go

@@ -0,0 +1,37 @@
+package exitcodes
+
+// ErrorWithExitCode is an `error` type that wraps an existing error and exit code, providing exit codes
+// for a given error if they are bubbled up to the top-level.
+type ErrorWithExitCode struct {
+	err      error
+	exitCode int
+}
+
+// NewErrorWithExitCode creates a new error (ErrorWithExitCode) with the provided internal error and exit code.
+func NewErrorWithExitCode(err error, exitCode int) *ErrorWithExitCode {
+	return &ErrorWithExitCode{
+		err:      err,
+		exitCode: exitCode,
+	}
+}
+
+// Error returns the error message string, implementing the `error` interface.
+func (e *ErrorWithExitCode) Error() string {
+	return e.err.Error()
+}
+
+// GetErrorExitCode checks the given exit code that the application should exit with, if this error is bubbled to
+// the top-level. This will be 0 for a nil error, 1 for a generic error, or arbitrary if the error is of type
+// ErrorWithExitCode.
+// Returns the exit code associated with the error.
+func GetErrorExitCode(err error) int {
+	// If we have no error, return 0, if we have a generic error, return 1, if we have a custom error code, unwrap
+	// and return it.
+	if err == nil {
+		return ExitCodeSuccess
+	} else if unwrappedErr, ok := err.(*ErrorWithExitCode); ok {
+		return unwrappedErr.exitCode
+	} else {
+		return ExitCodeGeneralError
+	}
+}

cmd/exitcodes/exit_codes.go

@@ -0,0 +1,21 @@
+package exitcodes
+
+const (
+	// ================================
+	// Platform-universal exit codes
+	// ================================
+
+	// ExitCodeSuccess indicates no errors or failures had occurred.
+	ExitCodeSuccess = 0
+
+	// ExitCodeGeneralError indicates some type of general error occurred.
+	ExitCodeGeneralError = 1
+
+	// ================================
+	// Application-specific exit codes
+	// ================================
+	// Note: Despite not being standardized, exit codes 2-5 are often used for common use cases, so we avoid them.
+
+	// ExitCodeTestFailed indicates a test case had failed.
+	ExitCodeTestFailed = 7
+)

cmd/fuzz.go

@@ -2,6 +2,7 @@ package cmd
 
 import (
 	"fmt"
+	"github.com/crytic/medusa/cmd/exitcodes"
 	"github.com/crytic/medusa/logging/colors"
 	"os"
 	"os/signal"
@@ -160,5 +161,10 @@ func cmdRunFuzz(cmd *cobra.Command, args []string) error {
 	// Start the fuzzing process with our cancellable context.
 	err = fuzzer.Start()
 
+	// If we have no error and failed test cases, we'll want to return a special exit code
+	if err == nil && len(fuzzer.TestCasesWithStatus(fuzzing.TestCaseStatusFailed)) > 0 {
+		return exitcodes.NewErrorWithExitCode(err, exitcodes.ExitCodeTestFailed)
+	}
+
 	return err
 }

main.go

@@ -2,14 +2,14 @@ package main
 
 import (
 	"github.com/crytic/medusa/cmd"
+	"github.com/crytic/medusa/cmd/exitcodes"
 	"os"
 )
 
 func main() {
 	// Run our root CLI command, which contains all underlying command logic and will handle parsing/invocation.
 	err := cmd.Execute()
 
-	if err != nil {
-		os.Exit(1)
-	}
+	// Determine the exit code from any potential error and exit out.
+	os.Exit(exitcodes.GetErrorExitCode(err))
 }