trim-newline

Author: erkkikeranen

src/clojure_string.rs

@@ -6,6 +6,7 @@ pub(crate) mod lower_case;
 pub(crate) mod reverse;
 pub(crate) mod starts_with_qmark_;
 pub(crate) mod trim;
+pub(crate) mod trim_newline;
 pub(crate) mod triml;
 pub(crate) mod trimr;
 pub(crate) mod upper_case;

src/clojure_string/trim_newline.rs

@@ -0,0 +1,60 @@
+use crate::ifn::IFn;
+use crate::value::{ToValue, Value};
+use std::rc::Rc;
+
+use crate::error_message;
+use crate::type_tag::TypeTag;
+
+/// clojure.string/trim_newline trims white space from start of string
+#[derive(Debug, Clone)]
+pub struct TrimNewlineFn {}
+impl ToValue for TrimNewlineFn {
+ fn to_value(&self) -> Value {
+ Value::IFn(Rc::new(self.clone()))
+ }
+}
+impl IFn for TrimNewlineFn {
+ fn invoke(&self, args: Vec<Rc<Value>>) -> Value {
+ if args.len() != 1 {
+ return error_message::wrong_arg_count(1, args.len());
+ } else {
+ match args.get(0).unwrap().to_value() {
+ Value::String(s) => {
+ Value::String(s.trim_end_matches(|c| c == '\n' || c == '\r').to_string())
+ }
+ _a => error_message::type_mismatch(TypeTag::String, &_a.to_value()),
+ }
+ }
+ }
+}
+
+#[cfg(test)]
+mod tests {
+ mod trim_newline_tests {
+ use crate::clojure_string::trim_newline::TrimNewlineFn;
+ use crate::ifn::IFn;
+ use crate::value::Value;
+ use std::rc::Rc;
+
+ #[test]
+ fn trim_newline() {
+ let trim_newline = TrimNewlineFn {};
+ let s = " \r \t hello \n\r";
+ let args = vec![Rc::new(Value::String(String::from(s)))];
+ assert_eq!(
+ Value::String(String::from(" \r \t hello ")),
+ trim_newline.invoke(args)
+ );
+ }
+ #[test]
+ fn trim_newline_does_nothing() {
+ let trim_newline = TrimNewlineFn {};
+ let s = " \r \t hello . ";
+ let args = vec![Rc::new(Value::String(String::from(s)))];
+ assert_eq!(
+ Value::String(String::from(" \r \t hello . ")),
+ trim_newline.invoke(args)
+ );
+ }
+ }
+}

src/environment.rs

@@ -214,6 +214,7 @@ impl Environment {
  let trim_fn = clojure_string::trim::TrimFn {};
  let triml_fn = clojure_string::triml::TrimLFn {};
  let trimr_fn = clojure_string::trimr::TrimRFn {};
+ let trim_newline_fn = clojure_string::trim_newline::TrimNewlineFn {};
 
  // Hardcoded fns
  let lexical_eval_fn = Value::LexicalEvalFn {};
@@ -327,6 +328,12 @@ impl Environment {
  trimr_fn.to_rc_value(),
  );
 
+ environment.insert_into_namespace(
+ &Symbol::intern("clojure.string"),
+ Symbol::intern("trim-newline"),
+ trim_newline_fn.to_rc_value(),
+ );
+
  environment.insert(Symbol::intern("+"), add_fn.to_rc_value());
  environment.insert(Symbol::intern("let"), let_macro.to_rc_value());
  environment.insert(Symbol::intern("str"), str_fn.to_rc_value());