tests: Add tests for public interface of DecodeError

tests/src/decode_error.rs

@@ -0,0 +1,176 @@
+#![cfg(test)]
+
+use alloc::{boxed::Box, string::ToString, vec::Vec};
+use prost::Message;
+use protobuf::test_messages::proto3::TestAllTypesProto3;
+
+#[test]
+fn test_decode_error_invalid_wire_type() {
+    let msg = [0x36].as_slice();
+    assert_eq!(
+        TestAllTypesProto3::decode(msg).unwrap_err().to_string(),
+        "failed to decode Protobuf message: invalid wire type value: 6"
+    );
+}
+
+#[test]
+fn test_decode_error_invalid_varint() {
+    let msg = [0x08, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF].as_slice();
+    assert_eq!(
+        TestAllTypesProto3::decode(msg).unwrap_err().to_string(),
+        "failed to decode Protobuf message: TestAllTypesProto3.optional_int32: invalid varint"
+    );
+}
+
+#[test]
+fn test_decode_error_multiple_levels() {
+    use protobuf::test_messages::proto3::ForeignMessage;
+    let msg = TestAllTypesProto3 {
+        recursive_message: Some(Box::new(TestAllTypesProto3 {
+            optional_foreign_message: Some(ForeignMessage { c: -1 }),
+            ..Default::default()
+        })),
+        ..Default::default()
+    };
+    let mut buf = msg.encode_to_vec();
+
+    // Last byte is part of varint value `-1`. Set it to an invalid value.
+    assert_eq!(buf.last().unwrap(), &0x01);
+    *buf.last_mut().unwrap() = 0xFF;
+
+    assert_eq!(
+            TestAllTypesProto3::decode(buf.as_slice()).unwrap_err().to_string(),
+            "failed to decode Protobuf message: ForeignMessage.c: TestAllTypesProto3.optional_foreign_message: TestAllTypesProto3.recursive_message: invalid varint"
+        );
+}
+
+#[cfg(not(target_pointer_width = "64"))]
+#[test]
+fn test_decode_error_length_delimiter_too_large() {
+    assert!((usize::MAX as u64) < u64::MAX);
+
+    let msg = [0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x01].as_slice();
+    assert_eq!(
+        prost::decode_length_delimiter(msg).unwrap_err().to_string(),
+        "failed to decode Protobuf message: length delimiter exceeds maximum usize value"
+    );
+}
+
+#[cfg(not(feature = "no-recursion-limit"))]
+#[test]
+fn test_decode_error_recursion_limit_reached() {
+    let recursve_message = {
+        let mut msg = TestAllTypesProto3::default();
+        for _ in 0..101 {
+            msg = TestAllTypesProto3 {
+                recursive_message: Some(Box::new(msg)),
+                ..Default::default()
+            };
+        }
+        msg
+    };
+
+    let buf = recursve_message.encode_to_vec();
+    assert_eq!(
+        TestAllTypesProto3::decode(buf.as_slice()).unwrap_err().to_string(),
+        "failed to decode Protobuf message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: TestAllTypesProto3.recursive_message: recursion limit reached"
+    );
+}
+
+#[test]
+fn test_decode_error_invalid_key_value() {
+    let msg = [0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x01].as_slice();
+    assert_eq!(
+        TestAllTypesProto3::decode(msg).unwrap_err().to_string(),
+        "failed to decode Protobuf message: invalid key value: 1125899906842623"
+    );
+}
+
+#[test]
+fn test_decode_error_invalid_tag() {
+    let msg = [0x00].as_slice();
+    assert_eq!(
+        TestAllTypesProto3::decode(msg).unwrap_err().to_string(),
+        "failed to decode Protobuf message: invalid tag value: 0"
+    );
+}
+
+#[test]
+fn test_decode_error_unexpected_wire_type() {
+    let mut buf = [0x00].as_slice();
+    let mut msg = TestAllTypesProto3::default();
+    let ctx = prost::encoding::DecodeContext::default();
+    assert_eq!(
+        msg.merge_field(1, prost::encoding::WireType::LengthDelimited, &mut buf, ctx).unwrap_err().to_string(),
+        "failed to decode Protobuf message: TestAllTypesProto3.optional_int32: invalid wire type: LengthDelimited (expected Varint)"
+    );
+}
+
+#[test]
+fn test_decode_error_buffer_underflow() {
+    let msg = [0x12].as_slice();
+    assert_eq!(
+        TestAllTypesProto3::decode_length_delimited(msg)
+            .unwrap_err()
+            .to_string(),
+        "failed to decode Protobuf message: buffer underflow"
+    );
+}
+
+#[test]
+fn test_decode_error_invalid_string() {
+    let msg = TestAllTypesProto3 {
+        optional_string: "Hello".to_string(),
+        ..Default::default()
+    };
+    let mut buf = msg.encode_to_vec();
+
+    // Last byte is part of string value `o`. Set it to an invalid value.
+    assert_eq!(buf.last().unwrap(), &b'o');
+    *buf.last_mut().unwrap() = 0xA0;
+
+    assert_eq!(
+            TestAllTypesProto3::decode(buf.as_slice()).unwrap_err().to_string(),
+            "failed to decode Protobuf message: TestAllTypesProto3.optional_string: invalid string value: data is not UTF-8 encoded"
+        );
+}
+
+#[test]
+fn test_decode_error_any() {
+    use prost_types::{Any, Timestamp};
+
+    let msg = Any {
+        type_url: "non-existing-url".to_string(),
+        value: Vec::new(),
+    };
+
+    assert_eq!(
+        msg.to_msg::<Timestamp>().unwrap_err().to_string(),
+            "failed to decode Protobuf message: unexpected type URL.type_url: expected type URL: \"type.googleapis.com/google.protobuf.Timestamp\" (got: \"non-existing-url\")"
+        );
+}
+
+#[test]
+fn test_push() {
+    let mut decode_error = prost::DecodeError::new("something failed");
+    decode_error.push("Foo bad", "bar.foo");
+    decode_error.push("Baz bad", "bar.baz");
+
+    assert_eq!(
+        decode_error.to_string(),
+        "failed to decode Protobuf message: Foo bad.bar.foo: Baz bad.bar.baz: something failed"
+    );
+}
+
+#[cfg(feature = "std")]
+#[test]
+fn test_into_std_io_error() {
+    let decode_error = prost::DecodeError::new("something failed");
+    let std_io_error = std::io::Error::from(decode_error);
+
+    assert_eq!(std_io_error.kind(), std::io::ErrorKind::InvalidData);
+    assert_eq!(
+        std_io_error.to_string(),
+        "failed to decode Protobuf message: something failed"
+    );
+}

tests/src/lib.rs

@@ -24,6 +24,7 @@ cfg_if! {
     }
 }
 
+pub mod decode_error;
 pub mod extern_paths;
 pub mod no_root_packages;
 pub mod packages;