feat(revset): suggest similar branch names

lib/src/revset.rs

@@ -41,8 +41,11 @@ use crate::store::Store;
 /// Error occurred during symbol resolution.
 #[derive(Debug, Error)]
 pub enum RevsetResolutionError {
-    #[error("Revision \"{0}\" doesn't exist")]
-    NoSuchRevision(String),
+    #[error("Revision \"{name}\" doesn't exist")]
+    NoSuchRevision {
+        name: String,
+        candidates: Vec<String>,
+    },
     #[error("An empty string is not a valid revision")]
     EmptyString,
     #[error("Commit ID prefix \"{0}\" is ambiguous")]
@@ -1670,10 +1673,13 @@ pub struct FailingSymbolResolver;
 
 impl SymbolResolver for FailingSymbolResolver {
     fn resolve_symbol(&self, symbol: &str) -> Result<Vec<CommitId>, RevsetResolutionError> {
-        Err(RevsetResolutionError::NoSuchRevision(format!(
-            "Won't resolve symbol {symbol:?}. When creating revsets programmatically, avoid using \
-             RevsetExpression::symbol(); use RevsetExpression::commits() instead."
-        )))
+        Err(RevsetResolutionError::NoSuchRevision {
+            name: format!(
+                "Won't resolve symbol {symbol:?}. When creating revsets programmatically, avoid \
+                 using RevsetExpression::symbol(); use RevsetExpression::commits() instead."
+            ),
+            candidates: Default::default(),
+        })
     }
 }
 
@@ -1722,7 +1728,10 @@ impl SymbolResolver for DefaultSymbolResolver<'_> {
                 if let Some(workspace_id) = self.workspace_id {
                     workspace_id.clone()
                 } else {
-                    return Err(RevsetResolutionError::NoSuchRevision(symbol.to_owned()));
+                    return Err(RevsetResolutionError::NoSuchRevision {
+                        name: symbol.to_owned(),
+                        candidates: Default::default(),
+                    });
                 }
             } else {
                 WorkspaceId::new(symbol.strip_suffix('@').unwrap().to_string())
@@ -1730,7 +1739,10 @@ impl SymbolResolver for DefaultSymbolResolver<'_> {
             if let Some(commit_id) = self.repo.view().get_wc_commit_id(&target_workspace) {
                 Ok(vec![commit_id.clone()])
             } else {
-                Err(RevsetResolutionError::NoSuchRevision(symbol.to_owned()))
+                Err(RevsetResolutionError::NoSuchRevision {
+                    name: symbol.to_owned(),
+                    candidates: Default::default(),
+                })
             }
         } else if symbol == "root" {
             Ok(vec![self.repo.store().root_commit_id().clone()])
@@ -1791,7 +1803,13 @@ impl SymbolResolver for DefaultSymbolResolver<'_> {
                 }
             }
 
-            Err(RevsetResolutionError::NoSuchRevision(symbol.to_owned()))
+            Err(RevsetResolutionError::NoSuchRevision {
+                name: symbol.to_owned(),
+                candidates: {
+                    let branch_names = self.repo.view().branches().keys().collect_vec();
+                    collect_similar(symbol, &branch_names)
+                },
+            })
         }
     }
 }
@@ -1869,7 +1887,9 @@ fn resolve_symbols(
             RevsetExpression::Present(candidates) => {
                 resolve_symbols(repo, candidates.clone(), symbol_resolver)
                     .or_else(|err| match err {
-                        RevsetResolutionError::NoSuchRevision(_) => Ok(RevsetExpression::none()),
+                        RevsetResolutionError::NoSuchRevision { .. } => {
+                            Ok(RevsetExpression::none())
+                        }
                         RevsetResolutionError::EmptyString
                         | RevsetResolutionError::AmbiguousCommitIdPrefix(_)
                         | RevsetResolutionError::AmbiguousChangeIdPrefix(_)

lib/tests/test_revset.rs

@@ -21,7 +21,7 @@ use jujutsu_lib::commit::Commit;
 use jujutsu_lib::git;
 use jujutsu_lib::git_backend::GitBackend;
 use jujutsu_lib::index::{HexPrefix, PrefixResolution};
-use jujutsu_lib::op_store::{RefTarget, WorkspaceId};
+use jujutsu_lib::op_store::{BranchTarget, RefTarget, WorkspaceId};
 use jujutsu_lib::repo::Repo;
 use jujutsu_lib::repo_path::RepoPath;
 use jujutsu_lib::revset::{
@@ -174,13 +174,13 @@ fn test_resolve_symbol_commit_id() {
     );
     assert_matches!(
         resolve_symbol(repo.as_ref(), "040", None),
-        Err(RevsetResolutionError::NoSuchRevision(s)) if s == "040"
+        Err(RevsetResolutionError::NoSuchRevision{name, candidates}) if name == "040" && candidates.is_empty()
     );
 
     // Test non-hex string
     assert_matches!(
         resolve_symbol(repo.as_ref(), "foo", None),
-        Err(RevsetResolutionError::NoSuchRevision(s)) if s == "foo"
+        Err(RevsetResolutionError::NoSuchRevision{name, candidates}) if name == "foo" && candidates.is_empty()
     );
 
     // Test present() suppresses only NoSuchRevision error
@@ -313,7 +313,7 @@ fn test_resolve_symbol_change_id(readonly: bool) {
     );
     assert_matches!(
         resolve_symbol(repo, "zvlyw", None),
-        Err(RevsetResolutionError::NoSuchRevision(s)) if s == "zvlyw"
+        Err(RevsetResolutionError::NoSuchRevision{name, candidates}) if name == "zvlyw" && candidates.is_empty()
     );
 
     // Test that commit and changed id don't conflict ("040" and "zvz" are the
@@ -334,7 +334,10 @@ fn test_resolve_symbol_change_id(readonly: bool) {
     // Test non-hex string
     assert_matches!(
         resolve_symbol(repo, "foo", None),
-        Err(RevsetResolutionError::NoSuchRevision(s)) if s == "foo"
+        Err(RevsetResolutionError::NoSuchRevision{
+            name,
+            candidates
+        }) if name == "foo" && candidates.is_empty()
     );
 }
 
@@ -357,15 +360,24 @@ fn test_resolve_symbol_checkout(use_git: bool) {
     // With no workspaces, no variation can be resolved
     assert_matches!(
         resolve_symbol(mut_repo, "@", None),
-        Err(RevsetResolutionError::NoSuchRevision(s)) if s == "@"
+        Err(RevsetResolutionError::NoSuchRevision{
+            name,
+            candidates,
+        }) if name == "@" && candidates.is_empty()
     );
     assert_matches!(
         resolve_symbol(mut_repo, "@", Some(&ws1)),
-        Err(RevsetResolutionError::NoSuchRevision(s)) if s == "@"
+        Err(RevsetResolutionError::NoSuchRevision{
+            name,
+            candidates,
+        }) if name == "@" && candidates.is_empty()
     );
     assert_matches!(
         resolve_symbol(mut_repo, "ws1@", Some(&ws1)),
-        Err(RevsetResolutionError::NoSuchRevision(s)) if s == "ws1@"
+        Err(RevsetResolutionError::NoSuchRevision{
+            name,
+            candidates,
+        }) if name == "ws1@" && candidates.is_empty()
     );
 
     // Add some workspaces
@@ -376,7 +388,10 @@ fn test_resolve_symbol_checkout(use_git: bool) {
     // @ cannot be resolved without a default workspace ID
     assert_matches!(
         resolve_symbol(mut_repo, "@", None),
-        Err(RevsetResolutionError::NoSuchRevision(s)) if s == "@"
+        Err(RevsetResolutionError::NoSuchRevision{
+            name,
+            candidates,
+        }) if name == "@" && candidates.is_empty()
     );
     // Can resolve "@" shorthand with a default workspace ID
     assert_eq!(
@@ -432,7 +447,7 @@ fn test_resolve_symbol_git_refs() {
     // Nonexistent ref
     assert_matches!(
         resolve_symbol(mut_repo, "nonexistent", None),
-        Err(RevsetResolutionError::NoSuchRevision(s)) if s == "nonexistent"
+        Err(RevsetResolutionError::NoSuchRevision{name, candidates}) if name == "nonexistent" && candidates.is_empty()
     );
 
     // Full ref
@@ -2484,3 +2499,31 @@ fn test_change_id_index() {
     );
     assert_eq!(resolve_prefix("a"), PrefixResolution::AmbiguousMatch);
 }
+
+#[test]
+fn test_no_such_revision_suggestion() {
+    let settings = testutils::user_settings();
+    let test_repo = TestRepo::init(true);
+    let repo = &test_repo.repo;
+
+    let mut tx = repo.start_transaction(&settings, "test");
+    let mut_repo = tx.mut_repo();
+    let commit = write_random_commit(mut_repo, &settings);
+
+    for branch_name in ["foo", "bar", "baz"] {
+        mut_repo.set_branch(
+            branch_name.to_string(),
+            BranchTarget {
+                local_target: Some(RefTarget::Normal(commit.id().clone())),
+                remote_targets: Default::default(),
+            },
+        );
+    }
+
+    assert_matches!(resolve_symbol(mut_repo, "bar", None), Ok(_));
+    assert_matches!(
+        resolve_symbol(mut_repo, "bax", None),
+        Err(RevsetResolutionError::NoSuchRevision { name, candidates })
+        if name == "bax" && candidates == vec!["bar".to_string(), "baz".to_string()]
+    );
+}

src/cli_util.rs

@@ -279,7 +279,21 @@ impl From<RevsetParseError> for CommandError {
 
 impl From<RevsetResolutionError> for CommandError {
     fn from(err: RevsetResolutionError) -> Self {
-        user_error(format!("{err}"))
+        let hint = match &err {
+            RevsetResolutionError::NoSuchRevision {
+                name: _,
+                candidates,
+            } => format_similarity_hint(candidates),
+            RevsetResolutionError::EmptyString
+            | RevsetResolutionError::AmbiguousCommitIdPrefix(_)
+            | RevsetResolutionError::AmbiguousChangeIdPrefix(_)
+            | RevsetResolutionError::StoreError(_) => None,
+        };
+
+        CommandError::UserError {
+            message: format!("{err}"),
+            hint,
+        }
     }
 }