Return Error When Expression Can't Be Parsed

Update exprConverter function to return an error if the Expr expression
can't be parsed so it can be handled by the caller.

execution.go

@@ -99,7 +99,10 @@ func (e *Execution) ExecuteContext(ctx context.Context) (force.JobInfo, error) {
 		}
 	}
 	if e.Expr != "" {
-		e.Converter = exprConverter(e.Expr, apexContext)
+		e.Converter, err = exprConverter(e.Expr, apexContext)
+		if err != nil {
+			return result.JobInfo, fmt.Errorf("Expr error: %w", err)
+		}
 	} else if e.Converter == nil {
 		return result.JobInfo, fmt.Errorf("Expr or Converter must be defined")
 	}

expr.go

@@ -211,14 +211,14 @@ func exprFunctions() []expr.Option {
 	return exprFunctions
 }
 
-func exprConverter(expression string, context any) func(force.ForceRecord) []force.ForceRecord {
+func exprConverter(expression string, context any) (func(force.ForceRecord) []force.ForceRecord, error) {
 	env := Env{
 		"record": force.ForceRecord{},
 		"apex":   context,
 	}
 	program, err := expr.Compile(expression, append(exprFunctions(), expr.Env(env))...)
 	if err != nil {
-		log.Fatalln("Invalid expression:", err)
+		return nil, fmt.Errorf("Invalid expression: %w", err)
 	}
 	converter := func(record force.ForceRecord) []force.ForceRecord {
 		env := Env{
@@ -245,5 +245,5 @@ func exprConverter(expression string, context any) func(force.ForceRecord) []for
 		log.Warnln("Unexpected value.  It should be a map or array or maps.  Got", out)
 		return []force.ForceRecord{}
 	}
-	return converter
+	return converter, nil
 }