diff --git a/cli/src/cli_util.rs b/cli/src/cli_util.rs
index 4c0ceafcb..ddf69bca3 100644
--- a/cli/src/cli_util.rs
+++ b/cli/src/cli_util.rs
@@ -2652,15 +2652,15 @@ pub fn edit_temp_file(
 }
 
 pub fn short_commit_hash(commit_id: &CommitId) -> String {
-    commit_id.hex()[0..12].to_string()
+    format!("{commit_id:.12}")
 }
 
 pub fn short_change_hash(change_id: &ChangeId) -> String {
-    change_id.reverse_hex()[0..12].to_string()
+    format!("{change_id:.12}")
 }
 
 pub fn short_operation_hash(operation_id: &OperationId) -> String {
-    operation_id.hex()[0..12].to_string()
+    format!("{operation_id:.12}")
 }
 
 /// Wrapper around a `DiffEditor` to conditionally start interactive session.
diff --git a/cli/src/commands/debug/revset.rs b/cli/src/commands/debug/revset.rs
index f6ee8142e..55c309e2b 100644
--- a/cli/src/commands/debug/revset.rs
+++ b/cli/src/commands/debug/revset.rs
@@ -15,7 +15,6 @@
 use std::fmt::Debug;
 use std::io::Write as _;
 
-use jj_lib::object_id::ObjectId;
 use jj_lib::revset;
 use jj_lib::revset::RevsetDiagnostics;
 
@@ -69,7 +68,7 @@ pub fn cmd_debug_revset(
 
     writeln!(ui.stdout(), "-- Commit IDs:")?;
     for commit_id in revset.iter() {
-        writeln!(ui.stdout(), "{}", commit_id.hex())?;
+        writeln!(ui.stdout(), "{commit_id}")?;
     }
     Ok(())
 }
diff --git a/cli/src/diff_util.rs b/cli/src/diff_util.rs
index 495e06ae4..88ddefba2 100644
--- a/cli/src/diff_util.rs
+++ b/cli/src/diff_util.rs
@@ -850,7 +850,7 @@ fn diff_content(path: &RepoPath, value: MaterializedTreeValue) -> io::Result<Fil
         }),
         MaterializedTreeValue::GitSubmodule(id) => Ok(FileContent {
             is_binary: false,
-            contents: format!("Git submodule checked out at {}", id.hex()).into_bytes(),
+            contents: format!("Git submodule checked out at {id}").into_bytes(),
         }),
         // TODO: are we sure this is never binary?
         MaterializedTreeValue::FileConflict {
diff --git a/cli/src/merge_tools/builtin.rs b/cli/src/merge_tools/builtin.rs
index 8631a567c..1a5fdb8ef 100644
--- a/cli/src/merge_tools/builtin.rs
+++ b/cli/src/merge_tools/builtin.rs
@@ -37,7 +37,7 @@ pub enum BuiltinToolError {
     Record(#[from] scm_record::RecordError),
     #[error(transparent)]
     ReadFileBackend(BackendError),
-    #[error("Failed to read file {path:?} with ID {id}", id = id.hex())]
+    #[error("Failed to read file {path:?} with ID {id}")]
     ReadFileIo {
         path: RepoPathBuf,
         id: FileId,
diff --git a/lib/src/backend.rs b/lib/src/backend.rs
index c0031cc57..285cdd129 100644
--- a/lib/src/backend.rs
+++ b/lib/src/backend.rs
@@ -39,17 +39,17 @@ use crate::signing::SignResult;
 id_type!(
     /// Identifier for a [`Commit`] based on its content. When a commit is
     /// rewritten, its `CommitId` changes.
-    pub CommitId
+    pub CommitId { hex() }
 );
 id_type!(
     /// Stable identifier for a [`Commit`]. Unlike the `CommitId`, the `ChangeId`
     /// follows the commit and is not updated when the commit is rewritten.
-    pub ChangeId
+    pub ChangeId { reverse_hex() }
 );
-id_type!(pub TreeId);
-id_type!(pub FileId);
-id_type!(pub SymlinkId);
-id_type!(pub ConflictId);
+id_type!(pub TreeId { hex() });
+id_type!(pub FileId { hex() });
+id_type!(pub SymlinkId { hex() });
+id_type!(pub ConflictId { hex() });
 
 impl ChangeId {
     /// Returns the hex string representation of this ID, which uses `z-k`
@@ -240,7 +240,10 @@ pub enum BackendError {
         hash: String,
         source: Box<dyn std::error::Error + Send + Sync>,
     },
-    #[error("Error when reading file content for file {} with id {}", path.as_internal_file_string(), id.hex())]
+    #[error(
+        "Error when reading file content for file {path} with id {id}",
+        path = path.as_internal_file_string()
+    )]
     ReadFile {
         path: RepoPathBuf,
         id: FileId,
diff --git a/lib/src/default_index/store.rs b/lib/src/default_index/store.rs
index 8c516a0de..db348dc37 100644
--- a/lib/src/default_index/store.rs
+++ b/lib/src/default_index/store.rs
@@ -68,10 +68,7 @@ impl From<DefaultIndexStoreInitError> for BackendInitError {
 
 #[derive(Debug, Error)]
 pub enum DefaultIndexStoreError {
-    #[error(
-        "Failed to associate commit index file with an operation {op_id}",
-        op_id = op_id.hex()
-    )]
+    #[error("Failed to associate commit index file with an operation {op_id}")]
     AssociateIndex {
         op_id: OperationId,
         source: io::Error,
@@ -82,7 +79,7 @@ pub enum DefaultIndexStoreError {
     LoadIndex(ReadonlyIndexLoadError),
     #[error("Failed to write commit index file")]
     SaveIndex(#[source] io::Error),
-    #[error("Failed to index commits at operation {op_id}", op_id = op_id.hex())]
+    #[error("Failed to index commits at operation {op_id}")]
     IndexCommits {
         op_id: OperationId,
         source: BackendError,
diff --git a/lib/src/git.rs b/lib/src/git.rs
index b59a3c043..3c2699242 100644
--- a/lib/src/git.rs
+++ b/lib/src/git.rs
@@ -180,7 +180,7 @@ fn resolve_git_ref_to_commit_id(
 
 #[derive(Error, Debug)]
 pub enum GitImportError {
-    #[error("Failed to read Git HEAD target commit {id}", id=id.hex())]
+    #[error("Failed to read Git HEAD target commit {id}")]
     MissingHeadTarget {
         id: CommitId,
         #[source]
diff --git a/lib/src/git_backend.rs b/lib/src/git_backend.rs
index ce281819c..1f4e2e915 100644
--- a/lib/src/git_backend.rs
+++ b/lib/src/git_backend.rs
@@ -703,7 +703,7 @@ fn deserialize_extras(commit: &mut Commit, bytes: &[u8]) {
 /// Returns `RefEdit` that will create a ref in `refs/jj/keep` if not exist.
 /// Used for preventing GC of commits we create.
 fn to_no_gc_ref_update(id: &CommitId) -> gix::refs::transaction::RefEdit {
-    let name = format!("{NO_GC_REF_NAMESPACE}{}", id.hex());
+    let name = format!("{NO_GC_REF_NAMESPACE}{id}");
     let new = gix::refs::Target::Object(validate_git_object_id(id).unwrap());
     let expected = gix::refs::transaction::PreviousValue::ExistingMustMatch(new.clone());
     gix::refs::transaction::RefEdit {
diff --git a/lib/src/merge.rs b/lib/src/merge.rs
index 286dac1f4..7a3e00645 100644
--- a/lib/src/merge.rs
+++ b/lib/src/merge.rs
@@ -36,7 +36,6 @@ use crate::backend::TreeId;
 use crate::backend::TreeValue;
 use crate::content_hash::ContentHash;
 use crate::content_hash::DigestUpdate;
-use crate::object_id::ObjectId;
 use crate::repo_path::RepoPath;
 use crate::store::Store;
 use crate::tree::Tree;
@@ -665,25 +664,25 @@ fn describe_conflict_term(value: &TreeValue) -> String {
             id,
             executable: false,
         } => {
-            format!("file with id {}", id.hex())
+            format!("file with id {id}")
         }
         TreeValue::File {
             id,
             executable: true,
         } => {
-            format!("executable file with id {}", id.hex())
+            format!("executable file with id {id}")
         }
         TreeValue::Symlink(id) => {
-            format!("symlink with id {}", id.hex())
+            format!("symlink with id {id}")
         }
         TreeValue::Tree(id) => {
-            format!("tree with id {}", id.hex())
+            format!("tree with id {id}")
         }
         TreeValue::GitSubmodule(id) => {
-            format!("Git submodule with id {}", id.hex())
+            format!("Git submodule with id {id}")
         }
         TreeValue::Conflict(id) => {
-            format!("Conflict with id {}", id.hex())
+            format!("Conflict with id {id}")
         }
     }
 }
diff --git a/lib/src/object_id.rs b/lib/src/object_id.rs
index 061b68bf1..7756987d0 100644
--- a/lib/src/object_id.rs
+++ b/lib/src/object_id.rs
@@ -32,22 +32,22 @@ pub trait ObjectId {
 // ```no_run
 // id_type!(
 //     /// My favorite id type.
-//     pub MyId
+//     pub MyId { hex() }
 // );
 // ```
 macro_rules! id_type {
     (   $(#[$attr:meta])*
-        $vis:vis $name:ident
+        $vis:vis $name:ident { $hex_method:ident() }
     ) => {
         $(#[$attr])*
         #[derive(ContentHash, PartialEq, Eq, PartialOrd, Ord, Clone, Hash)]
         $vis struct $name(Vec<u8>);
-        $crate::object_id::impl_id_type!($name);
+        $crate::object_id::impl_id_type!($name, $hex_method);
     };
 }
 
 macro_rules! impl_id_type {
-    ($name:ident) => {
+    ($name:ident, $hex_method:ident) => {
         impl $name {
             pub fn new(value: Vec<u8>) -> Self {
                 Self(value)
@@ -73,10 +73,17 @@ macro_rules! impl_id_type {
 
         impl std::fmt::Debug for $name {
             fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> Result<(), std::fmt::Error> {
+                // TODO: should we use $hex_method here?
                 f.debug_tuple(stringify!($name)).field(&self.hex()).finish()
             }
         }
 
+        impl std::fmt::Display for $name {
+            fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> Result<(), std::fmt::Error> {
+                f.pad(&self.$hex_method())
+            }
+        }
+
         impl crate::object_id::ObjectId for $name {
             fn object_type(&self) -> String {
                 stringify!($name)
@@ -217,8 +224,20 @@ impl<T: Clone> PrefixResolution<T> {
 #[cfg(test)]
 mod tests {
     use super::*;
+    use crate::backend::ChangeId;
     use crate::backend::CommitId;
 
+    #[test]
+    fn test_display_object_id() {
+        let commit_id = CommitId::from_hex("deadbeef0123");
+        assert_eq!(format!("{commit_id}"), "deadbeef0123");
+        assert_eq!(format!("{commit_id:.6}"), "deadbe");
+
+        let change_id = ChangeId::from_hex("deadbeef0123");
+        assert_eq!(format!("{change_id}"), "mlpmollkzyxw");
+        assert_eq!(format!("{change_id:.6}"), "mlpmol");
+    }
+
     #[test]
     fn test_hex_prefix_prefixes() {
         let prefix = HexPrefix::new("").unwrap();
diff --git a/lib/src/op_store.rs b/lib/src/op_store.rs
index 0c64e07e0..635b2ed69 100644
--- a/lib/src/op_store.rs
+++ b/lib/src/op_store.rs
@@ -63,8 +63,8 @@ impl WorkspaceId {
     }
 }
 
-id_type!(pub ViewId);
-id_type!(pub OperationId);
+id_type!(pub ViewId { hex() });
+id_type!(pub OperationId { hex() });
 
 #[derive(ContentHash, PartialEq, Eq, Hash, Clone, Debug)]
 pub struct RefTarget {
diff --git a/lib/tests/test_revset.rs b/lib/tests/test_revset.rs
index 4ee99e123..bdfa0f6ee 100644
--- a/lib/tests/test_revset.rs
+++ b/lib/tests/test_revset.rs
@@ -1071,7 +1071,7 @@ fn test_evaluate_expression_heads() {
 
     // Heads of a single commit is that commit
     assert_eq!(
-        resolve_commit_ids(mut_repo, &format!("heads({})", commit2.id().hex())),
+        resolve_commit_ids(mut_repo, &format!("heads({})", commit2.id())),
         vec![commit2.id().clone()]
     );
 
@@ -1079,7 +1079,7 @@ fn test_evaluate_expression_heads() {
     assert_eq!(
         resolve_commit_ids(
             mut_repo,
-            &format!("heads({} | {})", commit2.id().hex(), commit3.id().hex())
+            &format!("heads({} | {})", commit2.id(), commit3.id())
         ),
         vec![commit3.id().clone()]
     );
@@ -1089,7 +1089,7 @@ fn test_evaluate_expression_heads() {
     assert_eq!(
         resolve_commit_ids(
             mut_repo,
-            &format!("heads({} | {})", commit1.id().hex(), commit3.id().hex())
+            &format!("heads({} | {})", commit1.id(), commit3.id())
         ),
         vec![commit3.id().clone()]
     );
@@ -1098,7 +1098,7 @@ fn test_evaluate_expression_heads() {
     assert_eq!(
         resolve_commit_ids(
             mut_repo,
-            &format!("heads({} | {})", commit3.id().hex(), commit4.id().hex())
+            &format!("heads({} | {})", commit3.id(), commit4.id())
         ),
         vec![commit4.id().clone(), commit3.id().clone()]
     );
@@ -1135,7 +1135,7 @@ fn test_evaluate_expression_roots() {
 
     // Roots of a single commit is that commit
     assert_eq!(
-        resolve_commit_ids(mut_repo, &format!("roots({})", commit2.id().hex())),
+        resolve_commit_ids(mut_repo, &format!("roots({})", commit2.id())),
         vec![commit2.id().clone()]
     );
 
@@ -1143,7 +1143,7 @@ fn test_evaluate_expression_roots() {
     assert_eq!(
         resolve_commit_ids(
             mut_repo,
-            &format!("roots({} | {})", commit2.id().hex(), commit3.id().hex())
+            &format!("roots({} | {})", commit2.id(), commit3.id())
         ),
         vec![commit2.id().clone()]
     );
@@ -1153,7 +1153,7 @@ fn test_evaluate_expression_roots() {
     assert_eq!(
         resolve_commit_ids(
             mut_repo,
-            &format!("roots({} | {})", commit1.id().hex(), commit3.id().hex())
+            &format!("roots({} | {})", commit1.id(), commit3.id())
         ),
         vec![commit1.id().clone()]
     );
@@ -1195,53 +1195,44 @@ fn test_evaluate_expression_parents() {
 
     // Can find parents of a merge commit
     assert_eq!(
-        resolve_commit_ids(mut_repo, &format!("{}-", commit4.id().hex())),
+        resolve_commit_ids(mut_repo, &format!("{}-", commit4.id())),
         vec![commit3.id().clone(), commit2.id().clone()]
     );
 
     // Parents of all commits in input are returned
     assert_eq!(
-        resolve_commit_ids(
-            mut_repo,
-            &format!("({} | {})-", commit2.id().hex(), commit3.id().hex())
-        ),
+        resolve_commit_ids(mut_repo, &format!("({} | {})-", commit2.id(), commit3.id())),
         vec![commit1.id().clone(), root_commit.id().clone()]
     );
 
     // Parents already in input set are returned
     assert_eq!(
-        resolve_commit_ids(
-            mut_repo,
-            &format!("({} | {})-", commit1.id().hex(), commit2.id().hex())
-        ),
+        resolve_commit_ids(mut_repo, &format!("({} | {})-", commit1.id(), commit2.id())),
         vec![commit1.id().clone(), root_commit.id().clone()]
     );
 
     // Parents shared among commits in input are not repeated
     assert_eq!(
-        resolve_commit_ids(
-            mut_repo,
-            &format!("({} | {})-", commit4.id().hex(), commit5.id().hex())
-        ),
+        resolve_commit_ids(mut_repo, &format!("({} | {})-", commit4.id(), commit5.id())),
         vec![commit3.id().clone(), commit2.id().clone()]
     );
 
     // Can find parents of parents, which may be optimized to single query
     assert_eq!(
-        resolve_commit_ids(mut_repo, &format!("{}--", commit4.id().hex())),
+        resolve_commit_ids(mut_repo, &format!("{}--", commit4.id())),
         vec![commit1.id().clone(), root_commit.id().clone()]
     );
     assert_eq!(
         resolve_commit_ids(
             mut_repo,
-            &format!("({} | {})--", commit4.id().hex(), commit5.id().hex())
+            &format!("({} | {})--", commit4.id(), commit5.id())
         ),
         vec![commit1.id().clone(), root_commit.id().clone()]
     );
     assert_eq!(
         resolve_commit_ids(
             mut_repo,
-            &format!("({} | {})--", commit4.id().hex(), commit2.id().hex())
+            &format!("({} | {})--", commit4.id(), commit2.id())
         ),
         vec![commit1.id().clone(), root_commit.id().clone()]
     );
@@ -1287,10 +1278,7 @@ fn test_evaluate_expression_children() {
     // Children of all commits in input are returned, including those already in the
     // input set
     assert_eq!(
-        resolve_commit_ids(
-            mut_repo,
-            &format!("({} | {})+", commit1.id().hex(), commit2.id().hex())
-        ),
+        resolve_commit_ids(mut_repo, &format!("({} | {})+", commit1.id(), commit2.id())),
         vec![
             commit4.id().clone(),
             commit3.id().clone(),
@@ -1300,10 +1288,7 @@ fn test_evaluate_expression_children() {
 
     // Children shared among commits in input are not repeated
     assert_eq!(
-        resolve_commit_ids(
-            mut_repo,
-            &format!("({} | {})+", commit3.id().hex(), commit4.id().hex())
-        ),
+        resolve_commit_ids(mut_repo, &format!("({} | {})+", commit3.id(), commit4.id())),
         vec![commit5.id().clone()]
     );
 
@@ -1313,7 +1298,7 @@ fn test_evaluate_expression_children() {
         vec![commit4.id().clone(), commit2.id().clone()]
     );
     assert_eq!(
-        resolve_commit_ids(mut_repo, &format!("(root() | {})++", commit1.id().hex())),
+        resolve_commit_ids(mut_repo, &format!("(root() | {})++", commit1.id())),
         vec![
             commit5.id().clone(),
             commit4.id().clone(),
@@ -1324,7 +1309,7 @@ fn test_evaluate_expression_children() {
     assert_eq!(
         resolve_commit_ids(
             mut_repo,
-            &format!("({} | {})++", commit4.id().hex(), commit2.id().hex())
+            &format!("({} | {})++", commit4.id(), commit2.id())
         ),
         vec![commit6.id().clone(), commit5.id().clone()]
     );
@@ -1357,7 +1342,7 @@ fn test_evaluate_expression_ancestors() {
     // Can find ancestors of a specific commit. Commits reachable via multiple paths
     // are not repeated.
     assert_eq!(
-        resolve_commit_ids(mut_repo, &format!("::{}", commit4.id().hex())),
+        resolve_commit_ids(mut_repo, &format!("::{}", commit4.id())),
         vec![
             commit4.id().clone(),
             commit3.id().clone(),
@@ -1370,7 +1355,7 @@ fn test_evaluate_expression_ancestors() {
     // Can find ancestors of parents or parents of ancestors, which may be optimized
     // to single query
     assert_eq!(
-        resolve_commit_ids(mut_repo, &format!("::({}-)", commit4.id().hex()),),
+        resolve_commit_ids(mut_repo, &format!("::({}-)", commit4.id())),
         vec![
             commit3.id().clone(),
             commit2.id().clone(),
@@ -1381,7 +1366,7 @@ fn test_evaluate_expression_ancestors() {
     assert_eq!(
         resolve_commit_ids(
             mut_repo,
-            &format!("(::({}|{}))-", commit3.id().hex(), commit2.id().hex()),
+            &format!("(::({}|{}))-", commit3.id(), commit2.id()),
         ),
         vec![
             commit2.id().clone(),
@@ -1392,7 +1377,7 @@ fn test_evaluate_expression_ancestors() {
     assert_eq!(
         resolve_commit_ids(
             mut_repo,
-            &format!("::(({}|{})-)", commit3.id().hex(), commit2.id().hex()),
+            &format!("::(({}|{})-)", commit3.id(), commit2.id()),
         ),
         vec![
             commit2.id().clone(),
@@ -1403,15 +1388,15 @@ fn test_evaluate_expression_ancestors() {
 
     // Can find last n ancestors of a commit
     assert_eq!(
-        resolve_commit_ids(mut_repo, &format!("ancestors({}, 0)", commit2.id().hex())),
+        resolve_commit_ids(mut_repo, &format!("ancestors({}, 0)", commit2.id())),
         vec![]
     );
     assert_eq!(
-        resolve_commit_ids(mut_repo, &format!("ancestors({}, 1)", commit3.id().hex())),
+        resolve_commit_ids(mut_repo, &format!("ancestors({}, 1)", commit3.id())),
         vec![commit3.id().clone()]
     );
     assert_eq!(
-        resolve_commit_ids(mut_repo, &format!("ancestors({}, 3)", commit3.id().hex())),
+        resolve_commit_ids(mut_repo, &format!("ancestors({}, 3)", commit3.id())),
         vec![
             commit3.id().clone(),
             commit2.id().clone(),
@@ -1440,28 +1425,19 @@ fn test_evaluate_expression_range() {
 
     // Linear range
     assert_eq!(
-        resolve_commit_ids(
-            mut_repo,
-            &format!("{}..{}", commit1.id().hex(), commit3.id().hex())
-        ),
+        resolve_commit_ids(mut_repo, &format!("{}..{}", commit1.id(), commit3.id())),
         vec![commit3.id().clone(), commit2.id().clone()]
     );
 
     // Empty range (descendant first)
     assert_eq!(
-        resolve_commit_ids(
-            mut_repo,
-            &format!("{}..{}", commit3.id().hex(), commit1.id().hex())
-        ),
+        resolve_commit_ids(mut_repo, &format!("{}..{}", commit3.id(), commit1.id())),
         vec![]
     );
 
     // Range including a merge
     assert_eq!(
-        resolve_commit_ids(
-            mut_repo,
-            &format!("{}..{}", commit1.id().hex(), commit4.id().hex())
-        ),
+        resolve_commit_ids(mut_repo, &format!("{}..{}", commit1.id(), commit4.id())),
         vec![
             commit4.id().clone(),
             commit3.id().clone(),
@@ -1471,31 +1447,25 @@ fn test_evaluate_expression_range() {
 
     // Range including merge ancestors: commit4-- == root | commit2
     assert_eq!(
-        resolve_commit_ids(
-            mut_repo,
-            &format!("{}--..{}", commit4.id().hex(), commit3.id().hex())
-        ),
+        resolve_commit_ids(mut_repo, &format!("{}--..{}", commit4.id(), commit3.id())),
         vec![commit3.id().clone()]
     );
 
     // Sibling commits
     assert_eq!(
-        resolve_commit_ids(
-            mut_repo,
-            &format!("{}..{}", commit2.id().hex(), commit3.id().hex())
-        ),
+        resolve_commit_ids(mut_repo, &format!("{}..{}", commit2.id(), commit3.id())),
         vec![commit3.id().clone()]
     );
 
     // Left operand defaults to root()
     assert_eq!(
-        resolve_commit_ids(mut_repo, &format!("..{}", commit2.id().hex())),
+        resolve_commit_ids(mut_repo, &format!("..{}", commit2.id())),
         vec![commit2.id().clone(), commit1.id().clone()]
     );
 
     // Right operand defaults to visible_heads()
     assert_eq!(
-        resolve_commit_ids(mut_repo, &format!("{}..", commit2.id().hex())),
+        resolve_commit_ids(mut_repo, &format!("{}..", commit2.id())),
         vec![commit4.id().clone(), commit3.id().clone()]
     );
 
@@ -1534,10 +1504,7 @@ fn test_evaluate_expression_dag_range() {
 
     // Linear range
     assert_eq!(
-        resolve_commit_ids(
-            mut_repo,
-            &format!("{}::{}", root_commit_id.hex(), commit2.id().hex())
-        ),
+        resolve_commit_ids(mut_repo, &format!("{}::{}", root_commit_id, commit2.id())),
         vec![
             commit2.id().clone(),
             commit1.id().clone(),
@@ -1547,16 +1514,13 @@ fn test_evaluate_expression_dag_range() {
 
     // Empty range
     assert_eq!(
-        resolve_commit_ids(
-            mut_repo,
-            &format!("{}::{}", commit2.id().hex(), commit4.id().hex())
-        ),
+        resolve_commit_ids(mut_repo, &format!("{}::{}", commit2.id(), commit4.id())),
         vec![]
     );
 
     // Empty root
     assert_eq!(
-        resolve_commit_ids(mut_repo, &format!("none()::{}", commit5.id().hex())),
+        resolve_commit_ids(mut_repo, &format!("none()::{}", commit5.id())),
         vec![],
     );
 
@@ -1564,12 +1528,7 @@ fn test_evaluate_expression_dag_range() {
     assert_eq!(
         resolve_commit_ids(
             mut_repo,
-            &format!(
-                "({}|{})::{}",
-                commit1.id().hex(),
-                commit2.id().hex(),
-                commit3.id().hex()
-            )
+            &format!("({}|{})::{}", commit1.id(), commit2.id(), commit3.id())
         ),
         vec![
             commit3.id().clone(),
@@ -1580,10 +1539,7 @@ fn test_evaluate_expression_dag_range() {
 
     // Including a merge
     assert_eq!(
-        resolve_commit_ids(
-            mut_repo,
-            &format!("{}::{}", commit1.id().hex(), commit5.id().hex())
-        ),
+        resolve_commit_ids(mut_repo, &format!("{}::{}", commit1.id(), commit5.id())),
         vec![
             commit5.id().clone(),
             commit4.id().clone(),
@@ -1595,10 +1551,7 @@ fn test_evaluate_expression_dag_range() {
 
     // Including a merge, but ancestors only from one side
     assert_eq!(
-        resolve_commit_ids(
-            mut_repo,
-            &format!("{}::{}", commit2.id().hex(), commit5.id().hex())
-        ),
+        resolve_commit_ids(mut_repo, &format!("{}::{}", commit2.id(), commit5.id())),
         vec![
             commit5.id().clone(),
             commit3.id().clone(),
@@ -1649,11 +1602,7 @@ fn test_evaluate_expression_connected() {
     assert_eq!(
         resolve_commit_ids(
             mut_repo,
-            &format!(
-                "connected({} | {})",
-                root_commit_id.hex(),
-                commit2.id().hex()
-            )
+            &format!("connected({} | {})", root_commit_id, commit2.id())
         ),
         vec![commit2.id().clone(), commit1.id().clone(), root_commit_id]
     );
@@ -1662,7 +1611,7 @@ fn test_evaluate_expression_connected() {
     assert_eq!(
         resolve_commit_ids(
             mut_repo,
-            &format!("connected({} | {})", commit2.id().hex(), commit4.id().hex())
+            &format!("connected({} | {})", commit2.id(), commit4.id())
         ),
         vec![commit4.id().clone(), commit2.id().clone()]
     );
@@ -1671,7 +1620,7 @@ fn test_evaluate_expression_connected() {
     assert_eq!(
         resolve_commit_ids(
             mut_repo,
-            &format!("connected({} | {})", commit1.id().hex(), commit5.id().hex())
+            &format!("connected({} | {})", commit1.id(), commit5.id())
         ),
         vec![
             commit5.id().clone(),
@@ -1686,7 +1635,7 @@ fn test_evaluate_expression_connected() {
     assert_eq!(
         resolve_commit_ids(
             mut_repo,
-            &format!("connected({} | {})", commit2.id().hex(), commit5.id().hex())
+            &format!("connected({} | {})", commit2.id(), commit5.id())
         ),
         vec![
             commit5.id().clone(),
@@ -1748,8 +1697,8 @@ fn test_evaluate_expression_reachable() {
             mut_repo,
             &format!(
                 "reachable({}, all() ~ ::{})",
-                graph1commit2.id().hex(),
-                graph1commit1.id().hex()
+                graph1commit2.id(),
+                graph1commit1.id()
             )
         ),
         vec![graph1commit3.id().clone(), graph1commit2.id().clone(),]
@@ -1759,8 +1708,8 @@ fn test_evaluate_expression_reachable() {
             mut_repo,
             &format!(
                 "reachable({}, all() ~ ::{})",
-                graph1commit2.id().hex(),
-                graph1commit3.id().hex()
+                graph1commit2.id(),
+                graph1commit3.id()
             )
         ),
         vec![]
@@ -1774,7 +1723,7 @@ fn test_evaluate_expression_reachable() {
         assert_eq!(
             resolve_commit_ids(
                 mut_repo,
-                &format!("reachable({}, all() ~ root())", commit.id().hex())
+                &format!("reachable({}, all() ~ root())", commit.id())
             ),
             vec![
                 graph1commit3.id().clone(),
@@ -1793,7 +1742,7 @@ fn test_evaluate_expression_reachable() {
         assert_eq!(
             resolve_commit_ids(
                 mut_repo,
-                &format!("reachable({}, all() ~ root())", commit.id().hex())
+                &format!("reachable({}, all() ~ root())", commit.id())
             ),
             vec![
                 graph2commit3.id().clone(),
@@ -1820,7 +1769,7 @@ fn test_evaluate_expression_reachable() {
         assert_eq!(
             resolve_commit_ids(
                 mut_repo,
-                &format!("reachable({}, all() ~ root())", commit.id().hex())
+                &format!("reachable({}, all() ~ root())", commit.id())
             ),
             vec![
                 graph3commit7.id().clone(),
@@ -1842,8 +1791,8 @@ fn test_evaluate_expression_reachable() {
             mut_repo,
             &format!(
                 "reachable({}, all() ~ ::{})",
-                graph3commit4.id().hex(),
-                graph3commit5.id().hex()
+                graph3commit4.id(),
+                graph3commit5.id()
             )
         ),
         vec![
@@ -1902,7 +1851,7 @@ fn test_evaluate_expression_descendants() {
 
     // Can find descendants of a specific commit
     assert_eq!(
-        resolve_commit_ids(mut_repo, &format!("{}::", commit2.id().hex())),
+        resolve_commit_ids(mut_repo, &format!("{}::", commit2.id())),
         vec![
             commit6.id().clone(),
             commit5.id().clone(),
@@ -1914,7 +1863,7 @@ fn test_evaluate_expression_descendants() {
     // Can find descendants of children or children of descendants, which may be
     // optimized to single query
     assert_eq!(
-        resolve_commit_ids(mut_repo, &format!("({}+)::", commit1.id().hex())),
+        resolve_commit_ids(mut_repo, &format!("({}+)::", commit1.id())),
         vec![
             commit6.id().clone(),
             commit5.id().clone(),
@@ -1924,7 +1873,7 @@ fn test_evaluate_expression_descendants() {
         ]
     );
     assert_eq!(
-        resolve_commit_ids(mut_repo, &format!("({}++)::", commit1.id().hex())),
+        resolve_commit_ids(mut_repo, &format!("({}++)::", commit1.id())),
         vec![
             commit6.id().clone(),
             commit5.id().clone(),
@@ -1934,7 +1883,7 @@ fn test_evaluate_expression_descendants() {
     assert_eq!(
         resolve_commit_ids(
             mut_repo,
-            &format!("(({}|{})::)+", commit4.id().hex(), commit2.id().hex()),
+            &format!("(({}|{})::)+", commit4.id(), commit2.id()),
         ),
         vec![
             commit6.id().clone(),
@@ -1945,7 +1894,7 @@ fn test_evaluate_expression_descendants() {
     assert_eq!(
         resolve_commit_ids(
             mut_repo,
-            &format!("(({}|{})+)::", commit4.id().hex(), commit2.id().hex()),
+            &format!("(({}|{})+)::", commit4.id(), commit2.id()),
         ),
         vec![
             commit6.id().clone(),
@@ -1956,15 +1905,15 @@ fn test_evaluate_expression_descendants() {
 
     // Can find next n descendants of a commit
     assert_eq!(
-        resolve_commit_ids(mut_repo, &format!("descendants({}, 0)", commit2.id().hex())),
+        resolve_commit_ids(mut_repo, &format!("descendants({}, 0)", commit2.id())),
         vec![]
     );
     assert_eq!(
-        resolve_commit_ids(mut_repo, &format!("descendants({}, 1)", commit3.id().hex())),
+        resolve_commit_ids(mut_repo, &format!("descendants({}, 1)", commit3.id())),
         vec![commit3.id().clone()]
     );
     assert_eq!(
-        resolve_commit_ids(mut_repo, &format!("descendants({}, 3)", commit3.id().hex())),
+        resolve_commit_ids(mut_repo, &format!("descendants({}, 3)", commit3.id())),
         vec![
             commit6.id().clone(),
             commit5.id().clone(),
@@ -2485,7 +2434,7 @@ fn test_evaluate_expression_merges() {
     );
     // Searches only among candidates if specified
     assert_eq!(
-        resolve_commit_ids(mut_repo, &format!("::{} & merges()", commit5.id().hex())),
+        resolve_commit_ids(mut_repo, &format!("::{} & merges()", commit5.id())),
         vec![commit5.id().clone()]
     );
 }
@@ -2611,7 +2560,7 @@ fn test_evaluate_expression_author() {
     assert_eq!(
         resolve_commit_ids(
             mut_repo,
-            &format!("root().. & (author(name1) | {})", commit3.id().hex())
+            &format!("root().. & (author(name1) | {})", commit3.id())
         ),
         vec![commit3.id().clone(), commit1.id().clone()]
     );
@@ -2812,10 +2761,7 @@ fn test_evaluate_expression_mine() {
     );
     // Filter by union of pure predicate and set
     assert_eq!(
-        resolve_commit_ids(
-            mut_repo,
-            &format!("root().. & (mine() | {})", commit1.id().hex())
-        ),
+        resolve_commit_ids(mut_repo, &format!("root().. & (mine() | {})", commit1.id())),
         vec![
             commit3.id().clone(),
             commit2.id().clone(),
@@ -3048,7 +2994,7 @@ fn test_evaluate_expression_union() {
     assert_eq!(
         resolve_commit_ids(
             mut_repo,
-            &format!("::{} | ::{}", commit4.id().hex(), commit5.id().hex())
+            &format!("::{} | ::{}", commit4.id(), commit5.id())
         ),
         vec![
             commit5.id().clone(),
@@ -3066,9 +3012,9 @@ fn test_evaluate_expression_union() {
             mut_repo,
             &format!(
                 "(::{} ~ ::{}) | ::{}",
-                commit4.id().hex(),
-                commit2.id().hex(),
-                commit5.id().hex()
+                commit4.id(),
+                commit2.id(),
+                commit5.id()
             )
         ),
         vec![
@@ -3087,9 +3033,9 @@ fn test_evaluate_expression_union() {
             mut_repo,
             &format!(
                 "(::{} ~ ::{}) | {}",
-                commit4.id().hex(),
-                commit2.id().hex(),
-                commit5.id().hex(),
+                commit4.id(),
+                commit2.id(),
+                commit5.id(),
             )
         ),
         vec![
@@ -3114,7 +3060,7 @@ fn test_evaluate_expression_machine_generated_union() {
 
     // This query shouldn't trigger stack overflow. Here we use "x::y" in case
     // we had optimization path for trivial "commit_id|.." expression.
-    let revset_str = iter::repeat(format!("({}::{})", commit1.id().hex(), commit2.id().hex()))
+    let revset_str = iter::repeat(format!("({}::{})", commit1.id(), commit2.id()))
         .take(5000)
         .join("|");
     assert_eq!(
@@ -3143,7 +3089,7 @@ fn test_evaluate_expression_intersection() {
     assert_eq!(
         resolve_commit_ids(
             mut_repo,
-            &format!("::{} & ::{}", commit4.id().hex(), commit5.id().hex())
+            &format!("::{} & ::{}", commit4.id(), commit5.id())
         ),
         vec![
             commit2.id().clone(),
@@ -3154,10 +3100,7 @@ fn test_evaluate_expression_intersection() {
 
     // Intersection of disjoint sets
     assert_eq!(
-        resolve_commit_ids(
-            mut_repo,
-            &format!("{} & {}", commit4.id().hex(), commit2.id().hex())
-        ),
+        resolve_commit_ids(mut_repo, &format!("{} & {}", commit4.id(), commit2.id())),
         vec![]
     );
 }
@@ -3180,7 +3123,7 @@ fn test_evaluate_expression_difference() {
 
     // Difference from all
     assert_eq!(
-        resolve_commit_ids(mut_repo, &format!("~::{}", commit5.id().hex())),
+        resolve_commit_ids(mut_repo, &format!("~::{}", commit5.id())),
         vec![commit4.id().clone(), commit3.id().clone()]
     );
 
@@ -3188,28 +3131,28 @@ fn test_evaluate_expression_difference() {
     assert_eq!(
         resolve_commit_ids(
             mut_repo,
-            &format!("::{} ~ ::{}", commit4.id().hex(), commit5.id().hex())
+            &format!("::{} ~ ::{}", commit4.id(), commit5.id())
         ),
         vec![commit4.id().clone(), commit3.id().clone()]
     );
     assert_eq!(
         resolve_commit_ids(
             mut_repo,
-            &format!("::{} ~ ::{}", commit5.id().hex(), commit4.id().hex())
+            &format!("::{} ~ ::{}", commit5.id(), commit4.id())
         ),
         vec![commit5.id().clone()]
     );
     assert_eq!(
         resolve_commit_ids(
             mut_repo,
-            &format!("~::{} & ::{}", commit4.id().hex(), commit5.id().hex())
+            &format!("~::{} & ::{}", commit4.id(), commit5.id())
         ),
         vec![commit5.id().clone()]
     );
     assert_eq!(
         resolve_commit_ids(
             mut_repo,
-            &format!("::{} ~ ::{}", commit4.id().hex(), commit2.id().hex())
+            &format!("::{} ~ ::{}", commit4.id(), commit2.id())
         ),
         vec![commit4.id().clone(), commit3.id().clone()]
     );
@@ -3218,12 +3161,7 @@ fn test_evaluate_expression_difference() {
     assert_eq!(
         resolve_commit_ids(
             mut_repo,
-            &format!(
-                "::{} ~ {} ~ {}",
-                commit4.id().hex(),
-                commit2.id().hex(),
-                commit3.id().hex()
-            )
+            &format!("::{} ~ {} ~ {}", commit4.id(), commit2.id(), commit3.id())
         ),
         vec![
             commit4.id().clone(),
@@ -3238,10 +3176,10 @@ fn test_evaluate_expression_difference() {
             mut_repo,
             &format!(
                 "(::{} ~ ::{}) ~ (::{} ~ ::{})",
-                commit4.id().hex(),
-                commit1.id().hex(),
-                commit3.id().hex(),
-                commit1.id().hex(),
+                commit4.id(),
+                commit1.id(),
+                commit3.id(),
+                commit1.id(),
             )
         ),
         vec![commit4.id().clone()]
@@ -3302,10 +3240,7 @@ fn test_evaluate_expression_filter_combinator() {
     assert_eq!(
         resolve_commit_ids(
             mut_repo,
-            &format!(
-                "{}.. & (description(1) | description(2))",
-                commit1.id().hex(),
-            )
+            &format!("{}.. & (description(1) | description(2))", commit1.id()),
         ),
         vec![commit2.id().clone()],
     );
@@ -3413,10 +3348,7 @@ fn test_evaluate_expression_file() {
     assert_eq!(
         resolve_commit_ids_in_workspace(
             mut_repo,
-            &format!(
-                r#"{}:: & files("added_modified_clean")"#,
-                commit2.id().hex()
-            ),
+            &format!(r#"{}:: & files("added_modified_clean")"#, commit2.id()),
             &test_workspace.workspace,
             Some(test_workspace.workspace.workspace_root()),
         ),
@@ -3425,7 +3357,7 @@ fn test_evaluate_expression_file() {
 
     // empty() revset, which is identical to ~file(".")
     assert_eq!(
-        resolve_commit_ids(mut_repo, &format!("{}:: & empty()", commit1.id().hex())),
+        resolve_commit_ids(mut_repo, &format!("{}:: & empty()", commit1.id())),
         vec![commit4.id().clone()]
     );
 }
diff --git a/lib/testutils/src/lib.rs b/lib/testutils/src/lib.rs
index b6750e9c3..c9fe5f996 100644
--- a/lib/testutils/src/lib.rs
+++ b/lib/testutils/src/lib.rs
@@ -430,18 +430,13 @@ pub fn dump_tree(store: &Arc<Store>, tree_id: &MergedTreeId) -> String {
             Ok(Some(TreeValue::File { id, executable: _ })) => {
                 let file_buf = read_file(store, &path, &id);
                 let file_contents = String::from_utf8_lossy(&file_buf);
-                writeln!(
-                    &mut buf,
-                    "  file {path:?} ({}): {file_contents:?}",
-                    id.hex()
-                )
-                .unwrap();
+                writeln!(&mut buf, "  file {path:?} ({id}): {file_contents:?}").unwrap();
             }
             Ok(Some(TreeValue::Symlink(id))) => {
-                writeln!(&mut buf, "  symlink {path:?} ({})", id.hex()).unwrap();
+                writeln!(&mut buf, "  symlink {path:?} ({id})").unwrap();
             }
             Ok(Some(TreeValue::GitSubmodule(id))) => {
-                writeln!(&mut buf, "  submodule {path:?} ({})", id.hex()).unwrap();
+                writeln!(&mut buf, "  submodule {path:?} ({id})").unwrap();
             }
             entry => {
                 unimplemented!("dumping tree entry {entry:?}");