core/low: add trim type

Cargo.toml

@@ -26,6 +26,7 @@ number = []
 bool = []
 vec = []
 tuple = []
+low-level = []
 
 [dependencies]
 
@@ -38,4 +39,4 @@ required-features = ["vec", "number"]
 
 [[example]]
 name = "dotenv"
-required-features = ["vec", "tuple"]
+required-features = ["vec", "tuple", "low-level"]

examples/dotenv.rs

@@ -1,12 +1,13 @@
-use estring::{EString, Pair, SepVec};
+use estring::{EString, Pair, SepVec, Trim};
 
-const DOTENV_CONTENT: &str = "\
+const DOTENV_CONTENT: &str = "
 DATABASE_URL=postgres://user:password@localhost:5432/recipes
-APP_HOST=http://localhost:3000";
+APP_HOST=http://localhost:3000
+";
 
 fn main() -> Result<(), estring::ParseError> {
     EString::from(DOTENV_CONTENT)
-        .parse::<SepVec<Pair<&str, '=', &str>, '\n'>>()?
+        .parse::<Trim<SepVec<Pair<&str, '=', &str>, '\n'>>>()?
         .iter()
         .for_each(|p @ Pair(key, value)| {
             println!("pair: {}", p);

src/core.rs

@@ -16,6 +16,11 @@ pub mod tuple;
 #[cfg(feature = "tuple")]
 pub use tuple::*;
 
+#[cfg(feature = "low-level")]
+pub mod low;
+#[cfg(feature = "low-level")]
+pub use low::*;
+
 use crate::ParseError;
 use std::convert::{Infallible, TryFrom};
 

src/core/low.rs

@@ -0,0 +1,7 @@
+//! Contains the low-level api parse string more accurate!
+//!
+//! **NOTE**: Require the enabling the `low-level` feature.
+//!
+
+mod trim;
+pub use trim::*;

src/core/low/trim.rs

@@ -0,0 +1,78 @@
+use crate::core::EString;
+use std::convert::TryFrom;
+
+//===========================================================================//
+// TRIM                                                                      //
+//===========================================================================//
+
+/// Wrapper that allow to trim substring before continue
+///
+/// **NOTE**: Required the enabling of the `low-level` feature.
+///
+/// # Examples
+///
+/// ```rust
+/// use estring::{EString, Trim};
+///
+/// fn main() -> Result<(), estring::ParseError> {
+///     let res = EString::from(" 99 ").parse::<Trim<i32>>()?;
+///     assert_eq!(res, Trim(99));
+///     Ok(())
+/// }
+/// ```
+///
+#[derive(Debug, PartialEq, Eq)]
+pub struct Trim<T>(pub T);
+
+impl<T> std::ops::Deref for Trim<T> {
+    type Target = T;
+
+    fn deref(&self) -> &Self::Target {
+        &self.0
+    }
+}
+
+impl<T: std::fmt::Display> std::fmt::Display for Trim<T> {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        write!(f, "{}", self.0)
+    }
+}
+
+impl<T> TryFrom<EString> for Trim<T>
+where
+    T: TryFrom<EString>,
+{
+    type Error = ();
+
+    fn try_from(value: EString) -> Result<Self, Self::Error> {
+        T::try_from(EString::from(value.trim()))
+            .map(Trim)
+            .map_err(|_| ())
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn should_trim_string() {
+        let estr = EString::from("    999   ");
+
+        match estr.parse::<Trim<&str>>() {
+            Ok(res) => assert_eq!(*res, "999"),
+            _ => unreachable!(),
+        }
+    }
+
+    #[cfg(feature = "number")]
+    #[test]
+    fn should_trim_and_convert_to_number() {
+        let estr = EString::from("    999   ");
+
+        match estr.parse::<Trim<i32>>() {
+            Ok(res) => assert_eq!(*res, 999),
+            _ => unreachable!(),
+        }
+    }
+}

src/lib.rs

@@ -29,7 +29,7 @@
 //!
 #![deny(clippy::pedantic)]
 #![allow(clippy::module_name_repetitions)]
-#![deny(missing_docs)]
+#![warn(missing_docs)]
 
 pub mod core;
 mod error;