| 1 | 1 | | //! Greetings. |
| 2 | 2 | | |
| 3 | + | /// Parsed command-line options. |
| 4 | + | #[derive(Debug, Default, PartialEq, Eq)] |
| 5 | + | pub struct Options { |
| 6 | + | /// The name to greet, if one was given. |
| 7 | + | pub name: Option<String>, |
| 8 | + | } |
| 9 | + | |
| 10 | + | /// Parses command-line arguments (excluding the program name). |
| 11 | + | /// |
| 12 | + | /// Arguments starting with `--` are treated as flags and skipped; the name is |
| 13 | + | /// the first remaining argument. |
| 14 | + | pub fn parse_args<I: IntoIterator<Item = String>>(args: I) -> Options { |
| 15 | + | let name = args.into_iter().find(|arg| !arg.starts_with("--")); |
| 16 | + | Options { name } |
| 17 | + | } |
| 18 | + | |
| 3 | 19 | | /// The greeting for `name`. |
| 4 | 20 | | pub fn greeting(name: &str) -> String { |
| 5 | 21 | | let trimmed = name.trim(); |
| ⋯ |
| 18 | 34 | | mod tests { |
| 19 | 35 | | use super::*; |
| 20 | 36 | | |
| 37 | + | fn args(list: &[&str]) -> Vec<String> { |
| 38 | + | list.iter().map(|s| s.to_string()).collect() |
| 39 | + | } |
| 40 | + | |
| 41 | + | #[test] |
| 42 | + | fn parse_args_no_args() { |
| 43 | + | assert_eq!(parse_args(args(&[])).name, None); |
| 44 | + | } |
| 45 | + | |
| 46 | + | #[test] |
| 47 | + | fn parse_args_name() { |
| 48 | + | assert_eq!(parse_args(args(&["Ada"])).name.as_deref(), Some("Ada")); |
| 49 | + | } |
| 50 | + | |
| 51 | + | #[test] |
| 52 | + | fn parse_args_skips_leading_flag() { |
| 53 | + | assert_eq!( |
| 54 | + | parse_args(args(&["--unknown", "Ada"])).name.as_deref(), |
| 55 | + | Some("Ada") |
| 56 | + | ); |
| 57 | + | } |
| 58 | + | |
| 21 | 59 | | #[test] |
| 22 | 60 | | fn greets_by_name() { |
| 23 | 61 | | assert_eq!(greeting("Ada"), "Hello, Ada!"); |