Introduce a new structure to represent package requirements (#99)

With that change, the previous PackageRequirement structure was renamed
to SoftPackageRequirement, and the new structure took its original name.

libnest/src/cache/available/mod.rs

@@ -18,7 +18,7 @@ use failure::{Error, ResultExt};
 use serde_json;
 
 use crate::lock_file::LockFileOwnership;
-use crate::package::{PackageManifest, PackageRequirement};
+use crate::package::{PackageManifest, SoftPackageRequirement};
 use crate::repository::Repository;
 
 /// Structure representing the cache of available packages
@@ -87,7 +87,7 @@ impl<'cache_root, 'lock_file> AvailablePackages<'cache_root, 'lock_file> {
     #[inline]
     pub fn query<'pkg_req>(
         &self,
-        requirement: &'pkg_req PackageRequirement,
+        requirement: &'pkg_req SoftPackageRequirement,
     ) -> AvailablePackagesCacheQuery<'cache_root, 'pkg_req> {
         AvailablePackagesCacheQuery::from(&self.cache_root, requirement)
     }

libnest/src/cache/available/query.rs

@@ -4,8 +4,8 @@ use std::path::Path;
 use failure::{Error, ResultExt};
 
 use crate::package::{
-    CategoryName, Manifest, PackageFullName, PackageID, PackageManifest, PackageRequirement,
-    RepositoryName,
+    CategoryName, Manifest, PackageFullName, PackageID, PackageManifest, RepositoryName,
+    SoftPackageRequirement,
 };
 
 /// The result of a query to the packages cache
@@ -76,15 +76,15 @@ pub enum AvailablePackagesCacheQueryStrategy {
 #[derive(Clone, Eq, PartialEq, Hash, Debug)]
 pub struct AvailablePackagesCacheQuery<'a, 'b> {
     cache_root: &'a Path,
-    requirement: &'b PackageRequirement,
+    requirement: &'b SoftPackageRequirement,
     strategy: AvailablePackagesCacheQueryStrategy,
 }
 
 impl<'a, 'b> AvailablePackagesCacheQuery<'a, 'b> {
     #[inline]
     pub(crate) fn from(
         cache_root: &'a Path,
-        requirement: &'b PackageRequirement,
+        requirement: &'b SoftPackageRequirement,
     ) -> AvailablePackagesCacheQuery<'a, 'b> {
         AvailablePackagesCacheQuery {
             cache_root,

libnest/src/package/error.rs

@@ -92,13 +92,51 @@ pub enum PackageShortNameParseErrorKind {
 
 use_as_error!(PackageShortNameParseError, PackageShortNameParseErrorKind);
 
-/// Type for errors related to the parsing of a [`PackageRequirement`]
+/// Type for errors related to the parsing of a [`SoftPackageRequirement`]
+#[derive(Debug)]
+pub struct SoftPackageRequirementParseError {
+    inner: Context<SoftPackageRequirementParseErrorKind>,
+}
+
+/// Type describing a kind of error related to the parsing of a [`SoftPackageRequirement`]
+#[derive(Clone, Eq, PartialEq, Hash, Debug, Fail)]
+pub enum SoftPackageRequirementParseErrorKind {
+    /// The given string does not follow the format for package requirements
+    #[fail(
+        display = "\"{}\" doesn't follow the `repository::category/name#version` format",
+        _0
+    )]
+    InvalidFormat(String),
+
+    /// The name component of the package requirement has invalid characters
+    #[fail(display = "{}", _0)]
+    InvalidName(#[cause] PackageNameParseError),
+
+    /// The category component of the package requirement has invalid characters
+    #[fail(display = "{}", _0)]
+    InvalidCategory(#[cause] CategoryNameParseError),
+
+    /// The repository component of the package requirement has invalid characters
+    #[fail(display = "{}", _0)]
+    InvalidRepository(#[cause] RepositoryNameParseError),
+
+    /// The version component of the package requirement is not a valid version
+    #[fail(display = "invalid version syntax")]
+    InvalidVersion,
+}
+
+use_as_error!(
+    SoftPackageRequirementParseError,
+    SoftPackageRequirementParseErrorKind
+);
+
+/// Type for errors related to the parsing of a [`SoftPackageRequirement`]
 #[derive(Debug)]
 pub struct PackageRequirementParseError {
     inner: Context<PackageRequirementParseErrorKind>,
 }
 
-/// Type describing a kind of error related to the parsing of a [`PackageRequirement`]
+/// Type describing a kind of error related to the parsing of a [`SoftPackageRequirement`]
 #[derive(Clone, Eq, PartialEq, Hash, Debug, Fail)]
 pub enum PackageRequirementParseErrorKind {
     /// The given string does not follow the format for package requirements

libnest/src/package/mod.rs

@@ -82,7 +82,7 @@ pub use identification::{
 pub use manifest::{Kind, Manifest, PackageManifest, VersionData};
 pub use metadata::{License, Maintainer, Metadata, Tag, UpstreamURL};
 pub use npf::{NPFExplorer, NPFFile};
-pub use requirement::{HardPackageRequirement, PackageRequirement};
+pub use requirement::{HardPackageRequirement, PackageRequirement, SoftPackageRequirement};
 
 lazy_static::lazy_static! {
     /// A regular expression to match and parse a package's string representation