diff options
| -rw-r--r-- | README.md | 1 | ||||
| -rw-r--r-- | src/executor.rs | 50 |
2 files changed, 47 insertions, 4 deletions
@@ -136,6 +136,7 @@ Barb can include environment variable values and variables defined in `.env` int ``` {VARIABLE NAME} +{VARIABLE NAME:-DEFAULT} ``` This allows to do the following: diff --git a/src/executor.rs b/src/executor.rs index 54ca491..763b0e6 100644 --- a/src/executor.rs +++ b/src/executor.rs @@ -29,19 +29,29 @@ impl Context { } } + #[cfg(test)] fn key_str(&self, key: &String) -> String { + // Use for reference / utility? format!("{{{}}}", key) } pub fn substitute(&self, string: &String) -> String { let mut buffer = string.clone(); - let re = Regex::new(r"\{([A-Za-z0-9_]+)\}").unwrap(); + let re = Regex::new(r"\{(?P<key>[A-Za-z0-9_]+)(?::-(?P<value>.*))?\}").unwrap(); for var in re.captures_iter(string) { - let key = String::from(&var[1]); + let key = String::from(&var["key"]); + let value = String::from( + var.name("value") + .map(|m| m.as_str()) + .or(Some(&String::from(""))).unwrap() + ); + buffer = buffer.replace( - self.key_str(&key).as_str(), - self.vars.get(&key).or(Some(&String::from(""))).unwrap(), + // Since this iterates over matches, having match 0 is guaranteed. So the + // `unwrap()` operation here is safe. + var.get(0).unwrap().as_str(), + self.vars.get(&key).or(Some(&value)).unwrap() ); } @@ -197,6 +207,38 @@ mod tests_context { String::from("blah blah blah") ); } + + #[test] + fn test_context_substitute_default() { + let vars: Vec<(String, String)> = vec![]; + let ctx = Context::new(vars.into_iter()); + assert_eq!( + ctx.substitute(&String::from("blah blah {chewie:-wookie} blah")), + String::from("blah blah wookie blah") + ); + } + + #[test] + fn test_context_substitute_value_with_default() { + let vars: Vec<(String, String)> = vec![ + (String::from("chewie"), String::from("han")), + ]; + let ctx = Context::new(vars.into_iter()); + assert_eq!( + ctx.substitute(&String::from("blah blah {chewie:-wookie} blah")), + String::from("blah blah han blah") + ); + } + + #[test] + fn test_context_substitute_empty_default() { + let vars: Vec<(String, String)> = vec![]; + let ctx = Context::new(vars.into_iter()); + assert_eq!( + ctx.substitute(&String::from("blah blah {chewie:-} blah")), + String::from("blah blah blah") + ); + } } #[cfg(test)] |