change!: Change::Deleted variant now as versions to include all deleted versions. (#26)

That way it doesn't degenerate any information, previously the exact
version information was lost.

Not doing so helps to be able to reproduce the current state by
aggregating all changes.

Author: Byron

src/index/diff/delegate.rs

@@ -8,7 +8,7 @@ use std::ops::Range;
 #[derive(Default)]
 pub(crate) struct Delegate {
     changes: Vec<Change>,
-    delete_version_ids: BTreeSet<u64>,
+    deleted_version_ids: BTreeSet<u64>,
     err: Option<Error>,
 }
 
@@ -45,10 +45,16 @@ impl Delegate {
                     }
                 }
             }
-            Deletion { entry_mode, .. } => {
+            Deletion { entry_mode, id, .. } => {
                 if entry_mode.is_no_tree() {
+                    let obj = id.object()?;
+                    let mut deleted = Vec::with_capacity(obj.data.lines().count());
+                    for line in obj.data.lines() {
+                        deleted.push(version_from_json_line(line.into(), change.location)?);
+                    }
                     self.changes.push(Change::Deleted {
                         name: change.location.to_string(),
+                        versions: deleted,
                     });
                 }
             }
@@ -89,7 +95,7 @@ impl Delegate {
                                         for removed in lines_before {
                                             match version_from_json_line(removed, location) {
                                                 Ok(version) => {
-                                                    self.delete_version_ids.insert(version.id());
+                                                    self.deleted_version_ids.insert(version.id());
                                                 }
                                                 Err(e) => {
                                                     err = Some(e);
@@ -152,8 +158,8 @@ impl Delegate {
         match self.err {
             Some(err) => Err(err),
             None => {
-                if !self.delete_version_ids.is_empty() {
-                    let deleted_version_ids = &self.delete_version_ids;
+                if !self.deleted_version_ids.is_empty() {
+                    let deleted_version_ids = &self.deleted_version_ids;
                     self.changes.retain(|change| match change {
                         Change::Added(v) | Change::Yanked(v) => {
                             !deleted_version_ids.contains(&v.id())

src/types.rs

@@ -26,10 +26,12 @@ pub enum Change {
     Added(CrateVersion),
     /// A crate version was yanked.
     Yanked(CrateVersion),
-    /// The name of the deleted crate, which implies all versions were deleted as well.
+    /// The name of the crate whose file was deleted, which implies all versions were deleted as well.
     Deleted {
         /// The name of the deleted crate.
         name: String,
+        /// All of its versions that were deleted along with the file.
+        versions: Vec<CrateVersion>,
     },
 }
 
@@ -51,9 +53,9 @@ impl Change {
     }
 
     /// Return the deleted crate, if this is this kind of change.
-    pub fn deleted(&self) -> Option<&str> {
+    pub fn deleted(&self) -> Option<(&str, &[CrateVersion])> {
         match self {
-            Change::Deleted { name } => Some(name.as_str()),
+            Change::Deleted { name, versions } => Some((name.as_str(), versions)),
             _ => None,
         }
     }

tests/index/changes_between_commits.rs

@@ -6,7 +6,10 @@ use git_repository as git;
 fn directory_deletions_are_not_picked_up() -> crate::Result {
     let changes = changes(index_ro()?, ":/reproduce issue #20")?;
     assert_eq!(changes.len(), 1);
-    assert_eq!(changes.first().and_then(|c| c.deleted()), Some("allowed"));
+    assert_eq!(
+        changes.first().and_then(|c| c.deleted().map(|t| t.0)),
+        Some("allowed")
+    );
     Ok(())
 }
 
@@ -47,7 +50,10 @@ fn addition() -> crate::Result {
 fn deletion() -> crate::Result {
     let changes = changes(index_ro()?, "@^{/Delete crates}")?;
     assert_eq!(changes.len(), 1);
-    assert_eq!(changes.first().and_then(|c| c.deleted()), Some("girl"));
+    assert_eq!(
+        changes.first().and_then(|c| c.deleted().map(|t| t.0)),
+        Some("girl")
+    );
     Ok(())
 }