feat: sort extras by name and urls by filename (#540)

Sorts the extras according to name for consistency.

Also sorts the urls slightly different. Instead of sorting by the
complete url, now its first sorted by filename followed by the entire
url. This causes the urls to be sorted by package name most of the time
which reduces the diff if versions change.

Fixes prefix-dev/pixi#791

crates/rattler_lock/src/lib.rs

@@ -70,7 +70,7 @@
 use fxhash::FxHashMap;
 use pep508_rs::Requirement;
 use rattler_conda_types::{MatchSpec, PackageRecord, Platform, RepoDataRecord};
-use std::collections::{HashMap, HashSet};
+use std::collections::{BTreeSet, HashMap};
 use std::sync::Arc;
 use std::{borrow::Cow, io::Read, path::Path, str::FromStr};
 use url::Url;
@@ -550,7 +550,7 @@ impl PypiPackage {
     }
 
     /// Returns the extras enabled for this package
-    pub fn extras(&self) -> &HashSet<String> {
+    pub fn extras(&self) -> &BTreeSet<String> {
         &self.environment_data().extras
     }
 

crates/rattler_lock/src/parse/serialize.rs

@@ -4,10 +4,8 @@ use crate::{Channel, EnvironmentPackageData, LockFile, PypiPackageData};
 use itertools::Itertools;
 use rattler_conda_types::Platform;
 use serde::{Serialize, Serializer};
-use std::{
-    cmp::Ordering,
-    collections::{BTreeMap, HashSet},
-};
+use std::collections::{BTreeSet, HashSet};
+use std::{cmp::Ordering, collections::BTreeMap};
 use url::Url;
 
 #[derive(Serialize)]
@@ -31,16 +29,16 @@ enum SerializablePackageData<'a> {
     Pypi(&'a PypiPackageData),
 }
 
-#[derive(Serialize)]
+#[derive(Serialize, Eq, PartialEq)]
 #[serde(untagged, rename_all = "snake_case")]
 enum SerializablePackageSelector<'a> {
     Conda {
         conda: &'a Url,
     },
     Pypi {
         pypi: &'a Url,
-        #[serde(skip_serializing_if = "HashSet::is_empty")]
-        extras: &'a HashSet<String>,
+        #[serde(skip_serializing_if = "BTreeSet::is_empty")]
+        extras: &'a BTreeSet<String>,
     },
 }
 
@@ -53,6 +51,60 @@ impl<'a> SerializablePackageSelector<'a> {
     }
 }
 
+impl<'a> PartialOrd for SerializablePackageSelector<'a> {
+    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
+        Some(self.cmp(other))
+    }
+}
+
+impl<'a> Ord for SerializablePackageSelector<'a> {
+    fn cmp(&self, other: &Self) -> Ordering {
+        match (self, other) {
+            (
+                SerializablePackageSelector::Conda { .. },
+                SerializablePackageSelector::Pypi { .. },
+            ) => {
+                // Sort conda packages before pypi packages
+                Ordering::Less
+            }
+            (
+                SerializablePackageSelector::Pypi { .. },
+                SerializablePackageSelector::Conda { .. },
+            ) => {
+                // Sort Pypi packages after conda packages
+                Ordering::Greater
+            }
+            (
+                SerializablePackageSelector::Conda { conda: a },
+                SerializablePackageSelector::Conda { conda: b },
+            )
+            | (
+                SerializablePackageSelector::Pypi { pypi: a, .. },
+                SerializablePackageSelector::Pypi { pypi: b, .. },
+            ) => {
+                // First sort packages just by their filename. Since most of the time the urls end
+                // in the packages filename this causes the urls to be sorted by package name.
+                if let (Some(a), Some(b)) = (
+                    a.path_segments()
+                        .and_then(Iterator::last)
+                        .map(str::to_lowercase),
+                    b.path_segments()
+                        .and_then(Iterator::last)
+                        .map(str::to_lowercase),
+                ) {
+                    match a.cmp(&b) {
+                        Ordering::Equal => {}
+                        ordering => return ordering,
+                    }
+                }
+
+                // Otherwise just sort by their full URL
+                a.cmp(b)
+            }
+        }
+    }
+}
+
 impl<'a> SerializablePackageData<'a> {
     fn name(&self) -> &str {
         match self {
@@ -149,10 +201,7 @@ impl Serialize for LockFile {
                                                 }
                                             }
                                         })
-                                        .sorted_by_key(|p| match p {
-                                            SerializablePackageSelector::Conda { conda } => *conda,
-                                            SerializablePackageSelector::Pypi { pypi, .. } => *pypi,
-                                        })
+                                        .sorted()
                                         .collect(),
                                 )
                             })

crates/rattler_lock/src/pypi.rs

@@ -4,7 +4,7 @@ use pep508_rs::Requirement;
 use serde::{Deserialize, Serialize};
 use serde_with::{serde_as, skip_serializing_none};
 use std::cmp::Ordering;
-use std::collections::HashSet;
+use std::collections::BTreeSet;
 use url::Url;
 
 /// A pinned Pypi package
@@ -37,8 +37,8 @@ pub struct PypiPackageData {
 /// the same pypi package but with different extras enabled.
 #[derive(Clone, Debug, Default)]
 pub struct PypiPackageEnvironmentData {
-    /// The extras enabled for the package. Note that the order doesn't matter.
-    pub extras: HashSet<String>,
+    /// The extras enabled for the package. Note that the order doesn't matter here but it does matter for serialization.
+    pub extras: BTreeSet<String>,
 }
 
 impl PartialOrd for PypiPackageData {