call_method*() crashes when the method does not exist #113

CHANGES.txt

@@ -1,13 +1,15 @@
 Changes
 -------
 
-0.2.5 (2018-xx-xx)
+0.2.5 (2018-02-21)
 ^^^^^^^^^^^^^^^^^^
 
 * Embedded CPython 3.7b1 crashes on initialization #110
 
 * Generated extension functions are weakly typed #108
 
+* call_method*() crashes when the method does not exist #113
+
 
 0.2.4 (2018-01-19)
 ^^^^^^^^^^^^^^^^^^

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "pyo3"
-version = "0.2.4"
+version = "0.2.5"
 description = "Bindings to Python interpreter"
 authors = ["PyO3 Project and Contributors"]
 readme = "README.md"
@@ -19,7 +19,7 @@ appveyor = { repository = "PyO3/pyo3" }
 codecov = { repository = "PyO3/pyo3", branch = "master", service = "github" }
 
 [dependencies]
-log = "0.4"
+log = "0.5"
 libc = "0.2"
 spin = "0.4.6"
 num-traits = "0.1"

src/objectprotocol.rs

@@ -315,6 +315,9 @@ impl<T> ObjectProtocol for T where T: PyObjectWithToken + ToPyPointer {
     {
         name.with_borrowed_ptr(self.py(), |name| unsafe {
             let ptr = ffi::PyObject_GetAttr(self.as_ptr(), name);
+            if ptr.is_null() {
+                return Err(PyErr::fetch(self.py()))
+            }
             let args = args.into_tuple(self.py()).into_ptr();
             let kw_ptr = kwargs.into_dict_ptr(self.py());
             let result = self.py().from_owned_ptr_or_err(
@@ -330,6 +333,9 @@ impl<T> ObjectProtocol for T where T: PyObjectWithToken + ToPyPointer {
     {
         name.with_borrowed_ptr(self.py(), |name| unsafe {
             let ptr = ffi::PyObject_GetAttr(self.as_ptr(), name);
+            if ptr.is_null() {
+                return Err(PyErr::fetch(self.py()))
+            }
             let args = PyTuple::empty(self.py()).into_ptr();
             let result = self.py().from_owned_ptr_or_err(
                 ffi::PyObject_Call(ptr, args, std::ptr::null_mut()));
@@ -343,6 +349,9 @@ impl<T> ObjectProtocol for T where T: PyObjectWithToken + ToPyPointer {
     {
         name.with_borrowed_ptr(self.py(), |name| unsafe {
             let ptr = ffi::PyObject_GetAttr(self.as_ptr(), name);
+            if ptr.is_null() {
+                return Err(PyErr::fetch(self.py()))
+            }
             let args = args.into_tuple(self.py()).into_ptr();
             let result = self.py().from_owned_ptr_or_err(
                 ffi::PyObject_Call(ptr, args, std::ptr::null_mut()));
@@ -458,6 +467,7 @@ mod test {
     use python::Python;
     use conversion::{ToPyObject, PyTryFrom};
     use objects::PyString;
+    use super::*;
 
     #[test]
     fn test_debug_string() {
@@ -476,4 +486,15 @@ mod test {
         let s = PyString::try_from(v.as_ref(py)).unwrap();
         assert_eq!(format!("{}", s), "Hello\n");
     }
+
+    #[test]
+    fn test_call_for_non_existing_method() {
+        let gil = Python::acquire_gil();
+        let py = gil.python();
+        let a = py.eval("42", None, None).unwrap();
+        a.call_method0("__str__").unwrap();  // ok
+        assert!(a.call_method("nonexistent_method", (1,), ()).is_err());
+        assert!(a.call_method0("nonexistent_method").is_err());
+        assert!(a.call_method1("nonexistent_method", (1,)).is_err());
+    }
 }