--- a/rust/hg-cpython/src/dirstate/dirstate_map.rs	Tue Jan 28 22:27:30 2020 -0500
+++ b/rust/hg-cpython/src/dirstate/dirstate_map.rs	Sat Oct 12 23:34:05 2019 +0900
@@ -53,7 +53,7 @@
     }
 
     def clear(&self) -> PyResult<PyObject> {
-        self.inner_shared(py).borrow_mut()?.clear();
+        self.inner_shared(py).borrow_mut().clear();
         Ok(py.None())
     }
 
@@ -80,7 +80,7 @@
         size: PyObject,
         mtime: PyObject
     ) -> PyResult<PyObject> {
-        self.inner_shared(py).borrow_mut()?.add_file(
+        self.inner_shared(py).borrow_mut().add_file(
             HgPath::new(f.extract::<PyBytes>(py)?.data(py)),
             oldstate.extract::<PyBytes>(py)?.data(py)[0]
                 .try_into()
@@ -108,7 +108,7 @@
         oldstate: PyObject,
         size: PyObject
     ) -> PyResult<PyObject> {
-        self.inner_shared(py).borrow_mut()?
+        self.inner_shared(py).borrow_mut()
             .remove_file(
                 HgPath::new(f.extract::<PyBytes>(py)?.data(py)),
                 oldstate.extract::<PyBytes>(py)?.data(py)[0]
@@ -132,7 +132,7 @@
         f: PyObject,
         oldstate: PyObject
     ) -> PyResult<PyBool> {
-        self.inner_shared(py).borrow_mut()?
+        self.inner_shared(py).borrow_mut()
             .drop_file(
                 HgPath::new(f.extract::<PyBytes>(py)?.data(py)),
                 oldstate.extract::<PyBytes>(py)?.data(py)[0]
@@ -163,7 +163,7 @@
                 ))
             })
             .collect();
-        self.inner_shared(py).borrow_mut()?
+        self.inner_shared(py).borrow_mut()
             .clear_ambiguous_times(files?, now.extract(py)?);
         Ok(py.None())
     }
@@ -198,7 +198,7 @@
 
     def hastrackeddir(&self, d: PyObject) -> PyResult<PyBool> {
         let d = d.extract::<PyBytes>(py)?;
-        Ok(self.inner_shared(py).borrow_mut()?
+        Ok(self.inner_shared(py).borrow_mut()
             .has_tracked_dir(HgPath::new(d.data(py)))
             .map_err(|e| {
                 PyErr::new::<exc::ValueError, _>(py, e.to_string())
@@ -208,7 +208,7 @@
 
     def hasdir(&self, d: PyObject) -> PyResult<PyBool> {
         let d = d.extract::<PyBytes>(py)?;
-        Ok(self.inner_shared(py).borrow_mut()?
+        Ok(self.inner_shared(py).borrow_mut()
             .has_dir(HgPath::new(d.data(py)))
             .map_err(|e| {
                 PyErr::new::<exc::ValueError, _>(py, e.to_string())
@@ -217,7 +217,7 @@
     }
 
     def parents(&self, st: PyObject) -> PyResult<PyTuple> {
-        self.inner_shared(py).borrow_mut()?
+        self.inner_shared(py).borrow_mut()
             .parents(st.extract::<PyBytes>(py)?.data(py))
             .and_then(|d| {
                 Ok((PyBytes::new(py, &d.p1), PyBytes::new(py, &d.p2))
@@ -235,13 +235,13 @@
         let p1 = extract_node_id(py, &p1)?;
         let p2 = extract_node_id(py, &p2)?;
 
-        self.inner_shared(py).borrow_mut()?
+        self.inner_shared(py).borrow_mut()
             .set_parents(&DirstateParents { p1, p2 });
         Ok(py.None())
     }
 
     def read(&self, st: PyObject) -> PyResult<Option<PyObject>> {
-        match self.inner_shared(py).borrow_mut()?
+        match self.inner_shared(py).borrow_mut()
             .read(st.extract::<PyBytes>(py)?.data(py))
         {
             Ok(Some(parents)) => Ok(Some(
@@ -268,7 +268,7 @@
             p2: extract_node_id(py, &p2)?,
         };
 
-        match self.inner_shared(py).borrow_mut()?.pack(parents, now) {
+        match self.inner_shared(py).borrow_mut().pack(parents, now) {
             Ok(packed) => Ok(PyBytes::new(py, &packed)),
             Err(_) => Err(PyErr::new::<exc::OSError, _>(
                 py,
@@ -280,7 +280,7 @@
     def filefoldmapasdict(&self) -> PyResult<PyDict> {
         let dict = PyDict::new(py);
         for (key, value) in
-            self.inner_shared(py).borrow_mut()?.build_file_fold_map().iter()
+            self.inner_shared(py).borrow_mut().build_file_fold_map().iter()
         {
             dict.set_item(py, key.as_ref().to_vec(), value.as_ref().to_vec())?;
         }
@@ -336,7 +336,7 @@
 
     def getdirs(&self) -> PyResult<Dirs> {
         // TODO don't copy, share the reference
-        self.inner_shared(py).borrow_mut()?.set_dirs()
+        self.inner_shared(py).borrow_mut().set_dirs()
             .map_err(|e| {
                 PyErr::new::<exc::ValueError, _>(py, e.to_string())
             })?;
@@ -353,7 +353,7 @@
     }
     def getalldirs(&self) -> PyResult<Dirs> {
         // TODO don't copy, share the reference
-        self.inner_shared(py).borrow_mut()?.set_all_dirs()
+        self.inner_shared(py).borrow_mut().set_all_dirs()
             .map_err(|e| {
                 PyErr::new::<exc::ValueError, _>(py, e.to_string())
             })?;
@@ -431,7 +431,7 @@
     ) -> PyResult<PyObject> {
         let key = key.extract::<PyBytes>(py)?;
         let value = value.extract::<PyBytes>(py)?;
-        self.inner_shared(py).borrow_mut()?.copy_map.insert(
+        self.inner_shared(py).borrow_mut().copy_map.insert(
             HgPathBuf::from_bytes(key.data(py)),
             HgPathBuf::from_bytes(value.data(py)),
         );
@@ -445,7 +445,7 @@
         let key = key.extract::<PyBytes>(py)?;
         match self
             .inner_shared(py)
-            .borrow_mut()?
+            .borrow_mut()
             .copy_map
             .remove(HgPath::new(key.data(py)))
         {