[Rust] Flexbuffers dependency cleanup and fixes (#5998)

* Fix doc comment warnings

Can't use doc comment "///" syntax on macros, that generates the following warning:

warning: unused doc comment
   --> src\flexbuffer_type.rs:236:5
    |
236 |     /// returns true if and only if the flexbuffer type is `VectorFloat4`.
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ rustdoc does not generate documentation for macros
    |
    = help: to document an item produced by a macro, the macro must produce the documentation as part of its expansion

So switched to just use ordinary "//" comments on these to be warning free

* Upgrade num_enum 0.4.1 -> 0.5.0

* Remove unused and non-working usage of test crates

* Remove usage of abandoned debug_stub_derive crate

Which brought in old pre-v1 syn and quote crates.

This replaces it with just manual Debug trait implementation instead for the 2 cases

rust/flexbuffers/Cargo.toml

@@ -14,7 +14,6 @@ categories = ["encoding", "data-structures", "memory-management"]
 serde = "1.0"
 serde_derive = "1.0"
 byteorder = "1.3.2"
-num_enum = "0.4.1"
+num_enum = "0.5.0"
-debug_stub_derive = "0.3.0"
 bitflags = "1.2.1"
 

rust/flexbuffers/src/flexbuffer_type.rs

@@ -181,60 +181,60 @@ impl FlexBufferType {
             _ => None,
         }
     }
-    /// returns true if and only if the flexbuffer type is `Null`.
+    // returns true if and only if the flexbuffer type is `Null`.
     is_ty!(is_null, Null);
-    /// returns true if and only if the flexbuffer type is `Int`.
+    // returns true if and only if the flexbuffer type is `Int`.
     is_ty!(is_int, Int);
-    /// returns true if and only if the flexbuffer type is `UInt`.
+    // returns true if and only if the flexbuffer type is `UInt`.
     is_ty!(is_uint, UInt);
-    /// returns true if and only if the flexbuffer type is `Float`.
+    // returns true if and only if the flexbuffer type is `Float`.
     is_ty!(is_float, Float);
-    /// returns true if and only if the flexbuffer type is `Bool`.
+    // returns true if and only if the flexbuffer type is `Bool`.
     is_ty!(is_bool, Bool);
-    /// returns true if and only if the flexbuffer type is `Key`.
+    // returns true if and only if the flexbuffer type is `Key`.
     is_ty!(is_key, Key);
-    /// returns true if and only if the flexbuffer type is `String`.
+    // returns true if and only if the flexbuffer type is `String`.
     is_ty!(is_string, String);
-    /// returns true if and only if the flexbuffer type is `IndirectInt`.
+    // returns true if and only if the flexbuffer type is `IndirectInt`.
     is_ty!(is_indirect_int, IndirectInt);
-    /// returns true if and only if the flexbuffer type is `IndirectUInt`.
+    // returns true if and only if the flexbuffer type is `IndirectUInt`.
     is_ty!(is_indirect_uint, IndirectUInt);
-    /// returns true if and only if the flexbuffer type is `IndirectFloat`.
+    // returns true if and only if the flexbuffer type is `IndirectFloat`.
     is_ty!(is_indirect_float, IndirectFloat);
-    /// returns true if and only if the flexbuffer type is `Map`.
+    // returns true if and only if the flexbuffer type is `Map`.
     is_ty!(is_map, Map);
-    /// returns true if and only if the flexbuffer type is `Vector`.
+    // returns true if and only if the flexbuffer type is `Vector`.
     is_ty!(is_heterogenous_vector, Vector);
-    /// returns true if and only if the flexbuffer type is `VectorInt`.
+    // returns true if and only if the flexbuffer type is `VectorInt`.
     is_ty!(is_vector_int, VectorInt);
-    /// returns true if and only if the flexbuffer type is `VectorUInt`.
+    // returns true if and only if the flexbuffer type is `VectorUInt`.
     is_ty!(is_vector_uint, VectorUInt);
-    /// returns true if and only if the flexbuffer type is `VectorFloat`.
+    // returns true if and only if the flexbuffer type is `VectorFloat`.
     is_ty!(is_vector_float, VectorFloat);
-    /// returns true if and only if the flexbuffer type is `VectorKey`.
+    // returns true if and only if the flexbuffer type is `VectorKey`.
     is_ty!(is_vector_key, VectorKey);
-    /// returns true if and only if the flexbuffer type is `VectorString`.
+    // returns true if and only if the flexbuffer type is `VectorString`.
     is_ty!(is_vector_string, VectorString);
-    /// returns true if and only if the flexbuffer type is `VectorBool`.
+    // returns true if and only if the flexbuffer type is `VectorBool`.
     is_ty!(is_vector_bool, VectorBool);
-    /// returns true if and only if the flexbuffer type is `VectorInt2`.
+    // returns true if and only if the flexbuffer type is `VectorInt2`.
     is_ty!(is_vector_int2, VectorInt2);
-    /// returns true if and only if the flexbuffer type is `VectorUInt2`.
+    // returns true if and only if the flexbuffer type is `VectorUInt2`.
     is_ty!(is_vector_uint2, VectorUInt2);
-    /// returns true if and only if the flexbuffer type is `VectorFloat2`.
+    // returns true if and only if the flexbuffer type is `VectorFloat2`.
     is_ty!(is_vector_float2, VectorFloat2);
-    /// returns true if and only if the flexbuffer type is `VectorInt3`.
+    // returns true if and only if the flexbuffer type is `VectorInt3`.
     is_ty!(is_vector_int3, VectorInt3);
-    /// returns true if and only if the flexbuffer type is `VectorUInt3`.
+    // returns true if and only if the flexbuffer type is `VectorUInt3`.
     is_ty!(is_vector_uint3, VectorUInt3);
-    /// returns true if and only if the flexbuffer type is `VectorFloat3`.
+    // returns true if and only if the flexbuffer type is `VectorFloat3`.
     is_ty!(is_vector_float3, VectorFloat3);
-    /// returns true if and only if the flexbuffer type is `VectorInt4`.
+    // returns true if and only if the flexbuffer type is `VectorInt4`.
     is_ty!(is_vector_int4, VectorInt4);
-    /// returns true if and only if the flexbuffer type is `VectorUInt4`.
+    // returns true if and only if the flexbuffer type is `VectorUInt4`.
     is_ty!(is_vector_uint4, VectorUInt4);
-    /// returns true if and only if the flexbuffer type is `VectorFloat4`.
+    // returns true if and only if the flexbuffer type is `VectorFloat4`.
     is_ty!(is_vector_float4, VectorFloat4);
-    /// returns true if and only if the flexbuffer type is `Blob`.
+    // returns true if and only if the flexbuffer type is `Blob`.
     is_ty!(is_blob, Blob);
 }

rust/flexbuffers/src/lib.rs

@@ -12,7 +12,6 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-#![cfg_attr(test, feature(test))]
 //! Flexbuffers is a high performance schemaless binary data format designed at Google.
 //! It is complementary to the schema-ed format [Flatbuffers](http://docs.rs/flatbuffers/).
 //! See [Flexbuffer Internals](https://google.github.io/flatbuffers/flatbuffers_internals.html)
@@ -35,17 +34,8 @@ extern crate byteorder;
 #[macro_use]
 extern crate serde_derive;
 #[macro_use]
-extern crate debug_stub_derive;
 extern crate num_enum;
-#[cfg(test)]
-extern crate quickcheck;
-#[cfg(test)]
-extern crate quickcheck_derive;
-#[cfg(test)]
-extern crate rand;
 extern crate serde;
-#[cfg(test)]
-extern crate test;
 
 mod bitwidth;
 mod builder;

rust/flexbuffers/src/reader/map.rs

@@ -22,9 +22,8 @@ use std::iter::{DoubleEndedIterator, ExactSizeIterator, FusedIterator, Iterator}
 /// MapReaders may be indexed with strings or usizes. `index` returns a result type,
 /// which may indicate failure due to a missing key or bad data, `idx` returns an Null Reader in
 /// cases of error.
-#[derive(DebugStub, Default, Clone)]
+#[derive(Default, Clone)]
 pub struct MapReader<'de> {
-    #[debug_stub = "&[..]"]
     pub(super) buffer: &'de [u8],
     pub(super) values_address: usize,
     pub(super) keys_address: usize,
@@ -33,6 +32,20 @@ pub struct MapReader<'de> {
     pub(super) length: usize,
 }
 
+// manual implementation of Debug because buffer slice can't be automatically displayed
+impl<'de> std::fmt::Debug for MapReader<'de> {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        // skips buffer field
+        f.debug_struct("MapReader")
+            .field("values_address", &self.values_address)
+            .field("keys_address", &self.keys_address)
+            .field("values_width", &self.values_width)
+            .field("keys_width", &self.keys_width)
+            .field("length", &self.length)
+            .finish()
+    }
+}
+
 impl<'de> MapReader<'de> {
     /// Returns the number of key/value pairs are in the map.
     pub fn len(&self) -> usize {

rust/flexbuffers/src/reader/mod.rs

@@ -143,15 +143,27 @@ macro_rules! as_default {
 /// - The `as_T` methods will try their best to return to a value of type `T`
 /// (by casting or even parsing a string if necessary) but ultimately returns `T::default` if it
 /// fails. This behavior is analogous to that of flexbuffers C++.
-#[derive(DebugStub, Default, Clone)]
+#[derive(Default, Clone)]
 pub struct Reader<'de> {
     fxb_type: FlexBufferType,
     width: BitWidth,
     address: usize,
-    #[debug_stub = "&[..]"]
     buffer: &'de [u8],
 }
 
+// manual implementation of Debug because buffer slice can't be automatically displayed
+impl<'de> std::fmt::Debug for Reader<'de> {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        // skips buffer field
+        f.debug_struct("Reader")
+            .field("fxb_type", &self.fxb_type)
+            .field("width", &self.width)
+            .field("address", &self.address)
+            .finish()
+    }
+}
+
+
 macro_rules! try_cast_fn {
     ($name: ident, $full_width: ident, $Ty: ident) => {
         pub fn $name(&self) -> $Ty {