Rewrite PackageVersionConstraint constructing

Use the TryFrom trait rather than a `::new()` constructor that can fail.
This is way more idomatic.

Signed-off-by: Matthias Beyer <matthias.beyer@atos.net>

2 files changed, 21 insertions, 5 deletions

diff --git a/src/package/dependency/mod.rs b/src/package/dependency/mod.rs
index f2fd80f..e58d0a0 100644
--- a/src/package/dependency/mod.rs
+++ b/src/package/dependency/mod.rs
@@ -8,6 +8,8 @@
 // SPDX-License-Identifier: EPL-2.0
 //
 
+use std::convert::TryFrom;
+
 use anyhow::anyhow;
 use anyhow::Result;
 use lazy_static::lazy_static;
@@ -60,7 +62,7 @@ pub(in crate::package::dependency) fn parse_package_dependency_string_into_name_
         .map(|m| String::from(m.as_str()))
         .ok_or_else(|| anyhow!("Could not parse version: '{}'", s))?;
 
-    let v = PackageVersionConstraint::new(vers)?;
+    let v = PackageVersionConstraint::try_from(vers)?;
     Ok((PackageName::from(name), v))
 }
 
diff --git a/src/package/version.rs b/src/package/version.rs
index 0c3f7f6..9705c8d 100644
--- a/src/package/version.rs
+++ b/src/package/version.rs
@@ -25,10 +25,6 @@ pub struct PackageVersionConstraint {
 }
 
 impl PackageVersionConstraint {
-    pub fn new(s: String) -> Result<Self> {
-        Self::parser().parse(s.as_bytes()).map_err(Error::from)
-    }
-
     fn parser<'a>() -> PomParser<'a, u8, Self> {
         (pom::parser::sym(b'=') + PackageVersion::parser())
             .convert(|(constraint, version)| {
@@ -53,6 +49,24 @@ impl PackageVersionConstraint {
     }
 }
 
+impl std::convert::TryFrom<String> for PackageVersionConstraint {
+    type Error = anyhow::Error;
+
+    fn try_from(s: String) -> Result<Self> {
+        Self::try_from(&s as &str)
+    }
+}
+
+impl std::convert::TryFrom<&str> for PackageVersionConstraint {
+    type Error = anyhow::Error;
+
+    fn try_from(s: &str) -> Result<Self> {
+        PackageVersionConstraint::parser()
+            .parse(s.as_bytes())
+            .map_err(Error::from)
+    }
+}
+
 #[derive(
     parse_display::Display,
     Serialize,