id_prefix: remove repo field from IdPrefixContext

By passing the repo as argument to the methods instead, we can remove
the `repo` field and the associated lifetime. Thanks to Yuya for the
suggestion.

lib/src/id_prefix.rs

@@ -66,19 +66,12 @@ impl DisambiguationData {
     }
 }
 
-pub struct IdPrefixContext<'repo> {
+#[derive(Default)]
-    repo: &'repo dyn Repo,
+pub struct IdPrefixContext {
     disambiguation: Option<DisambiguationData>,
 }
 
-impl IdPrefixContext<'_> {
+impl IdPrefixContext {
-    pub fn new(repo: &dyn Repo) -> IdPrefixContext {
-        IdPrefixContext {
-            repo,
-            disambiguation: None,
-        }
-    }
-
     pub fn disambiguate_within(
         mut self,
         expression: Rc<RevsetExpression>,
@@ -92,59 +85,65 @@ impl IdPrefixContext<'_> {
         self
     }
 
-    fn disambiguation_indexes(&self) -> Option<&Indexes> {
+    fn disambiguation_indexes(&self, repo: &dyn Repo) -> Option<&Indexes> {
         // TODO: propagate errors instead of treating them as if no revset was specified
         self.disambiguation
             .as_ref()
-            .and_then(|disambiguation| disambiguation.indexes(self.repo).ok())
+            .and_then(|disambiguation| disambiguation.indexes(repo).ok())
     }
 
     /// Resolve an unambiguous commit ID prefix.
-    pub fn resolve_commit_prefix(&self, prefix: &HexPrefix) -> PrefixResolution<CommitId> {
+    pub fn resolve_commit_prefix(
-        if let Some(indexes) = self.disambiguation_indexes() {
+        &self,
+        repo: &dyn Repo,
+        prefix: &HexPrefix,
+    ) -> PrefixResolution<CommitId> {
+        if let Some(indexes) = self.disambiguation_indexes(repo) {
             let resolution = indexes.commit_index.resolve_prefix(prefix);
             if let PrefixResolution::SingleMatch(mut ids) = resolution {
                 assert_eq!(ids.len(), 1);
                 return PrefixResolution::SingleMatch(ids.pop().unwrap());
             }
         }
-        self.repo.index().resolve_prefix(prefix)
+        repo.index().resolve_prefix(prefix)
     }
 
     /// Returns the shortest length of a prefix of `commit_id` that
     /// can still be resolved by `resolve_commit_prefix()`.
-    pub fn shortest_commit_prefix_len(&self, commit_id: &CommitId) -> usize {
+    pub fn shortest_commit_prefix_len(&self, repo: &dyn Repo, commit_id: &CommitId) -> usize {
-        if let Some(indexes) = self.disambiguation_indexes() {
+        if let Some(indexes) = self.disambiguation_indexes(repo) {
             // TODO: Avoid the double lookup here (has_key() + shortest_unique_prefix_len())
             if indexes.commit_index.has_key(commit_id) {
                 return indexes.commit_index.shortest_unique_prefix_len(commit_id);
             }
         }
-        self.repo
+        repo.index().shortest_unique_commit_id_prefix_len(commit_id)
-            .index()
-            .shortest_unique_commit_id_prefix_len(commit_id)
     }
 
     /// Resolve an unambiguous change ID prefix to the commit IDs in the revset.
-    pub fn resolve_change_prefix(&self, prefix: &HexPrefix) -> PrefixResolution<Vec<CommitId>> {
+    pub fn resolve_change_prefix(
-        if let Some(indexes) = self.disambiguation_indexes() {
+        &self,
+        repo: &dyn Repo,
+        prefix: &HexPrefix,
+    ) -> PrefixResolution<Vec<CommitId>> {
+        if let Some(indexes) = self.disambiguation_indexes(repo) {
             let resolution = indexes.change_index.resolve_prefix(prefix);
             if let PrefixResolution::SingleMatch(ids) = resolution {
                 return PrefixResolution::SingleMatch(ids);
             }
         }
-        self.repo.resolve_change_id_prefix(prefix)
+        repo.resolve_change_id_prefix(prefix)
     }
 
     /// Returns the shortest length of a prefix of `change_id` that
     /// can still be resolved by `resolve_change_prefix()`.
-    pub fn shortest_change_prefix_len(&self, change_id: &ChangeId) -> usize {
+    pub fn shortest_change_prefix_len(&self, repo: &dyn Repo, change_id: &ChangeId) -> usize {
-        if let Some(indexes) = self.disambiguation_indexes() {
+        if let Some(indexes) = self.disambiguation_indexes(repo) {
             if indexes.change_index.has_key(change_id) {
                 return indexes.change_index.shortest_unique_prefix_len(change_id);
             }
         }
-        self.repo.shortest_unique_change_id_prefix_len(change_id)
+        repo.shortest_unique_change_id_prefix_len(change_id)
     }
 }
 

lib/src/revset.rs

@@ -1647,7 +1647,7 @@ impl SymbolResolver for FailingSymbolResolver {
     }
 }
 
-pub type PrefixResolver<'a, T> = Box<dyn Fn(&HexPrefix) -> PrefixResolution<T> + 'a>;
+pub type PrefixResolver<'a, T> = Box<dyn Fn(&dyn Repo, &HexPrefix) -> PrefixResolution<T> + 'a>;
 
 /// Resolves the "root" and "@" symbols, branches, remote branches, tags, git
 /// refs, and full and abbreviated commit and change ids.
@@ -1728,7 +1728,7 @@ impl SymbolResolver for DefaultSymbolResolver<'_> {
             // Try to resolve as a commit id.
             if let Some(prefix) = HexPrefix::new(symbol) {
                 let prefix_resolution = if let Some(commit_id_resolver) = &self.commit_id_resolver {
-                    commit_id_resolver(&prefix)
+                    commit_id_resolver(self.repo, &prefix)
                 } else {
                     self.repo.index().resolve_prefix(&prefix)
                 };
@@ -1748,7 +1748,7 @@ impl SymbolResolver for DefaultSymbolResolver<'_> {
             // Try to resolve as a change id.
             if let Some(prefix) = to_forward_hex(symbol).as_deref().and_then(HexPrefix::new) {
                 let prefix_resolution = if let Some(change_id_resolver) = &self.change_id_resolver {
-                    change_id_resolver(&prefix)
+                    change_id_resolver(self.repo, &prefix)
                 } else {
                     self.repo.resolve_change_id_prefix(&prefix)
                 };

lib/tests/test_id_prefix.rs

@@ -130,25 +130,55 @@ fn test_id_prefix() {
 
     // Without a disambiguation revset
     // ---------------------------------------------------------------------------------------------
-    let c = IdPrefixContext::new(repo.as_ref());
+    let c = IdPrefixContext::default();
-    assert_eq!(c.shortest_commit_prefix_len(commits[2].id()), 2);
-    assert_eq!(c.shortest_commit_prefix_len(commits[5].id()), 1);
-    assert_eq!(c.resolve_commit_prefix(&prefix("2")), AmbiguousMatch);
     assert_eq!(
-        c.resolve_commit_prefix(&prefix("2a")),
+        c.shortest_commit_prefix_len(repo.as_ref(), commits[2].id()),
+        2
+    );
+    assert_eq!(
+        c.shortest_commit_prefix_len(repo.as_ref(), commits[5].id()),
+        1
+    );
+    assert_eq!(
+        c.resolve_commit_prefix(repo.as_ref(), &prefix("2")),
+        AmbiguousMatch
+    );
+    assert_eq!(
+        c.resolve_commit_prefix(repo.as_ref(), &prefix("2a")),
         SingleMatch(commits[2].id().clone())
     );
-    assert_eq!(c.resolve_commit_prefix(&prefix("20")), NoMatch);
-    assert_eq!(c.resolve_commit_prefix(&prefix("2a0")), NoMatch);
-    assert_eq!(c.shortest_change_prefix_len(commits[0].change_id()), 2);
-    assert_eq!(c.shortest_change_prefix_len(commits[6].change_id()), 1);
-    assert_eq!(c.resolve_change_prefix(&prefix("7")), AmbiguousMatch);
     assert_eq!(
-        c.resolve_change_prefix(&prefix("78")),
+        c.resolve_commit_prefix(repo.as_ref(), &prefix("20")),
+        NoMatch
+    );
+    assert_eq!(
+        c.resolve_commit_prefix(repo.as_ref(), &prefix("2a0")),
+        NoMatch
+    );
+    assert_eq!(
+        c.shortest_change_prefix_len(repo.as_ref(), commits[0].change_id()),
+        2
+    );
+    assert_eq!(
+        c.shortest_change_prefix_len(repo.as_ref(), commits[6].change_id()),
+        1
+    );
+    assert_eq!(
+        c.resolve_change_prefix(repo.as_ref(), &prefix("7")),
+        AmbiguousMatch
+    );
+    assert_eq!(
+        c.resolve_change_prefix(repo.as_ref(), &prefix("78")),
         SingleMatch(vec![commits[0].id().clone()])
     );
-    assert_eq!(c.resolve_change_prefix(&prefix("70")), NoMatch);
+    assert_eq!(
-    assert_eq!(c.resolve_change_prefix(&prefix("780")), NoMatch);
+        c.resolve_change_prefix(repo.as_ref(), &prefix("70")),
+        NoMatch
+    );
+    assert_eq!(
+        c.resolve_change_prefix(repo.as_ref(), &prefix("780")),
+        NoMatch
+    );
 
     // Disambiguate within a revset
     // ---------------------------------------------------------------------------------------------
@@ -156,20 +186,26 @@ fn test_id_prefix() {
         RevsetExpression::commits(vec![commits[0].id().clone(), commits[2].id().clone()]);
     let c = c.disambiguate_within(expression, None);
     // The prefix is now shorter
-    assert_eq!(c.shortest_commit_prefix_len(commits[2].id()), 1);
+    assert_eq!(
+        c.shortest_commit_prefix_len(repo.as_ref(), commits[2].id()),
+        1
+    );
     // Shorter prefix within the set can be used
     assert_eq!(
-        c.resolve_commit_prefix(&prefix("2")),
+        c.resolve_commit_prefix(repo.as_ref(), &prefix("2")),
         SingleMatch(commits[2].id().clone())
     );
     // Can still resolve commits outside the set
     assert_eq!(
-        c.resolve_commit_prefix(&prefix("21")),
+        c.resolve_commit_prefix(repo.as_ref(), &prefix("21")),
         SingleMatch(commits[24].id().clone())
     );
-    assert_eq!(c.shortest_change_prefix_len(commits[0].change_id()), 1);
     assert_eq!(
-        c.resolve_change_prefix(&prefix("7")),
+        c.shortest_change_prefix_len(repo.as_ref(), commits[0].change_id()),
+        1
+    );
+    assert_eq!(
+        c.resolve_change_prefix(repo.as_ref(), &prefix("7")),
         SingleMatch(vec![commits[0].id().clone()])
     );
 
@@ -178,16 +214,28 @@ fn test_id_prefix() {
     // ---------------------------------------------------------------------------------------------
     let expression = RevsetExpression::commit(root_commit_id.clone());
     let c = c.disambiguate_within(expression, None);
-    assert_eq!(c.shortest_commit_prefix_len(root_commit_id), 1);
-    assert_eq!(c.resolve_commit_prefix(&prefix("")), AmbiguousMatch);
     assert_eq!(
-        c.resolve_commit_prefix(&prefix("0")),
+        c.shortest_commit_prefix_len(repo.as_ref(), root_commit_id),
+        1
+    );
+    assert_eq!(
+        c.resolve_commit_prefix(repo.as_ref(), &prefix("")),
+        AmbiguousMatch
+    );
+    assert_eq!(
+        c.resolve_commit_prefix(repo.as_ref(), &prefix("0")),
         SingleMatch(root_commit_id.clone())
     );
-    assert_eq!(c.shortest_change_prefix_len(root_change_id), 1);
-    assert_eq!(c.resolve_change_prefix(&prefix("")), AmbiguousMatch);
     assert_eq!(
-        c.resolve_change_prefix(&prefix("0")),
+        c.shortest_change_prefix_len(repo.as_ref(), root_change_id),
+        1
+    );
+    assert_eq!(
+        c.resolve_change_prefix(repo.as_ref(), &prefix("")),
+        AmbiguousMatch
+    );
+    assert_eq!(
+        c.resolve_change_prefix(repo.as_ref(), &prefix("0")),
         SingleMatch(vec![root_commit_id.clone()])
     );
 
@@ -196,6 +244,12 @@ fn test_id_prefix() {
     // TODO: Should be an error
     let expression = RevsetExpression::symbol("nonexistent".to_string());
     let context = c.disambiguate_within(expression, None);
-    assert_eq!(context.shortest_commit_prefix_len(commits[2].id()), 2);
+    assert_eq!(
-    assert_eq!(context.resolve_commit_prefix(&prefix("2")), AmbiguousMatch);
+        context.shortest_commit_prefix_len(repo.as_ref(), commits[2].id()),
+        2
+    );
+    assert_eq!(
+        context.resolve_commit_prefix(repo.as_ref(), &prefix("2")),
+        AmbiguousMatch
+    );
 }

src/cli_util.rs

@@ -548,7 +548,7 @@ impl CommandHelper {
 /// data is lazily loaded.
 struct ReadonlyUserRepo {
     repo: Arc<ReadonlyRepo>,
-    id_prefix_context: OnceCell<IdPrefixContext<'static>>,
+    id_prefix_context: OnceCell<IdPrefixContext>,
 }
 
 impl ReadonlyUserRepo {
@@ -590,7 +590,7 @@ impl WorkspaceCommandHelper {
         // Parse commit_summary template early to report error before starting mutable
         // operation.
         // TODO: Parsed template can be cached if it doesn't capture repo
-        let id_prefix_context = IdPrefixContext::new(repo.as_ref());
+        let id_prefix_context = IdPrefixContext::default();
         parse_commit_summary_template(
             repo.as_ref(),
             workspace.workspace_id(),
@@ -925,18 +925,18 @@ impl WorkspaceCommandHelper {
 
     pub(crate) fn revset_symbol_resolver(&self) -> DefaultSymbolResolver<'_> {
         let id_prefix_context = self.id_prefix_context();
-        let commit_id_resolver: revset::PrefixResolver<'_, CommitId> =
+        let commit_id_resolver: revset::PrefixResolver<CommitId> =
-            Box::new(|prefix| id_prefix_context.resolve_commit_prefix(prefix));
+            Box::new(|repo, prefix| id_prefix_context.resolve_commit_prefix(repo, prefix));
-        let change_id_resolver: revset::PrefixResolver<'_, Vec<CommitId>> =
+        let change_id_resolver: revset::PrefixResolver<Vec<CommitId>> =
-            Box::new(|prefix| id_prefix_context.resolve_change_prefix(prefix));
+            Box::new(|repo, prefix| id_prefix_context.resolve_change_prefix(repo, prefix));
         DefaultSymbolResolver::new(self.repo().as_ref(), Some(self.workspace_id()))
             .with_commit_id_resolver(commit_id_resolver)
             .with_change_id_resolver(change_id_resolver)
     }
 
-    pub fn id_prefix_context(&self) -> &IdPrefixContext<'_> {
+    pub fn id_prefix_context(&self) -> &IdPrefixContext {
         self.user_repo.id_prefix_context.get_or_init(|| {
-            let mut context: IdPrefixContext<'_> = IdPrefixContext::new(self.repo().as_ref());
+            let mut context: IdPrefixContext = IdPrefixContext::default();
             let revset_string: String = self
                 .settings
                 .config()
@@ -947,7 +947,6 @@ impl WorkspaceCommandHelper {
                 context = context
                     .disambiguate_within(disambiguation_revset, Some(self.workspace_id().clone()));
             }
-            let context: IdPrefixContext<'static> = unsafe { std::mem::transmute(context) };
             context
         })
     }
@@ -1295,7 +1294,7 @@ impl WorkspaceCommandTransaction<'_> {
         commit: &Commit,
     ) -> std::io::Result<()> {
         // TODO: Use the disambiguation revset
-        let id_prefix_context = IdPrefixContext::new(self.tx.repo());
+        let id_prefix_context = IdPrefixContext::default();
         let template = parse_commit_summary_template(
             self.tx.repo(),
             self.helper.workspace_id(),
@@ -1734,7 +1733,7 @@ fn load_template_aliases(
 fn parse_commit_summary_template<'a>(
     repo: &'a dyn Repo,
     workspace_id: &WorkspaceId,
-    id_prefix_context: &'a IdPrefixContext<'a>,
+    id_prefix_context: &'a IdPrefixContext,
     aliases_map: &TemplateAliasesMap,
     settings: &UserSettings,
 ) -> Result<Box<dyn Template<Commit> + 'a>, CommandError> {

src/commit_templater.rs

@@ -40,7 +40,7 @@ use crate::text_util;
 struct CommitTemplateLanguage<'repo, 'b> {
     repo: &'repo dyn Repo,
     workspace_id: &'b WorkspaceId,
-    id_prefix_context: &'repo IdPrefixContext<'repo>,
+    id_prefix_context: &'repo IdPrefixContext,
 }
 
 impl<'repo> TemplateLanguage<'repo> for CommitTemplateLanguage<'repo, '_> {
@@ -387,13 +387,14 @@ impl CommitOrChangeId {
     /// length of the shortest unique prefix
     pub fn shortest(
         &self,
+        repo: &dyn Repo,
         id_prefix_context: &IdPrefixContext,
         total_len: usize,
     ) -> ShortestIdPrefix {
         let mut hex = self.hex();
         let prefix_len = match self {
-            CommitOrChangeId::Commit(id) => id_prefix_context.shortest_commit_prefix_len(id),
+            CommitOrChangeId::Commit(id) => id_prefix_context.shortest_commit_prefix_len(repo, id),
-            CommitOrChangeId::Change(id) => id_prefix_context.shortest_change_prefix_len(id),
+            CommitOrChangeId::Change(id) => id_prefix_context.shortest_change_prefix_len(repo, id),
         };
         hex.truncate(max(prefix_len, total_len));
         let rest = hex.split_off(prefix_len);
@@ -434,6 +435,7 @@ fn build_commit_or_change_id_method<'repo>(
                 (self_property, len_property),
                 |(id, len)| {
                     id.shortest(
+                        language.repo,
                         id_prefix_context,
                         len.and_then(|l| l.try_into().ok()).unwrap_or(0),
                     )
@@ -515,7 +517,7 @@ fn build_shortest_id_prefix_method<'repo>(
 pub fn parse<'repo>(
     repo: &'repo dyn Repo,
     workspace_id: &WorkspaceId,
-    id_prefix_context: &'repo IdPrefixContext<'repo>,
+    id_prefix_context: &'repo IdPrefixContext,
     template_text: &str,
     aliases_map: &TemplateAliasesMap,
 ) -> TemplateParseResult<Box<dyn Template<Commit> + 'repo>> {