Printf with dynamic first argument and no further arguments SCC-SA1006
Bug risk
Major
4 months ago
—
4 years old
printf-style function with dynamic format string and no further arguments should use print-style function instead
97 }
98
99 paddingSize := widths[i] - len(column.Contents)
100 _, err = fmt.Fprintf(dst, strings.Repeat(" ", paddingSize))101 if err != nil {
102 return err
103 }printf-style function with dynamic format string and no further arguments should use print-style function instead
47 }
48 }
49 if workersNames == nil {
50 fmt.Printf(ui.WarningColor("WARNING: No stalled workers found.\n"))51 }
52 }
53
Description
Using fmt.Printf with a dynamic first argument can lead to unexpected output.
The first argument is a format string, where certain character combinations have
special meaning.
Forming the first parameter via string concatenation with user input should be
avoided for the same reason. When printing user input, either use a variant of
fmt.Print, or use the %s Printf verb and pass the string as an argument.
Bad practice
s := "Interest rate: 5%"
fmt.Printf(s) // Prints: Interest rate: 5%!(NOVERB)
Recommended
s := "Interest rate: 5%"
fmt.Print(s) // Prints: Interest rate: 5%
s := "Interest rate: 5%"
fmt.Printf("%s", s) // Prints: Interest rate: 5%