loosen lifetimes in type signature of Table::get (#4925)

rust/flatbuffers/src/table.rs

@@ -30,12 +30,12 @@ impl<'a> Table<'a> {
         Table { buf: buf, loc: loc }
     }
     #[inline]
-    pub fn vtable(&'a self) -> VTable<'a> {
+    pub fn vtable(&self) -> VTable<'a> {
         <BackwardsSOffset<VTable<'a>>>::follow(self.buf, self.loc)
     }
     #[inline]
     pub fn get<T: Follow<'a> + 'a>(
-        &'a self,
+        &self,
         slot_byte_loc: VOffsetT,
         default: Option<T::Inner>,
     ) -> Option<T::Inner> {

tests/rust_usage_test/tests/integration_test.rs

@@ -234,6 +234,37 @@ mod generated_constants {
     }
 }
 
+#[cfg(test)]
+mod lifetime_correctness {
+    extern crate flatbuffers;
+
+    use std::mem;
+
+    use super::my_game;
+    use super::load_file;
+
+    #[test]
+    fn table_get_field_from_static_buffer_1() {
+        let buf = load_file("../monsterdata_test.mon");
+        // create 'static slice
+        let slice: &[u8] = &buf;
+        let slice: &'static [u8] = unsafe { mem::transmute(slice) };
+        // make sure values retrieved from the 'static buffer are themselves 'static
+        let monster: my_game::example::Monster<'static> = my_game::example::get_root_as_monster(slice);
+        // this line should compile:
+        let name: Option<&'static str> = monster._tab.get::<flatbuffers::ForwardsUOffset<&str>>(my_game::example::Monster::VT_NAME, None);
+        assert_eq!(name, Some("MyMonster"));
+    }
+
+    #[test]
+    fn table_get_field_from_static_buffer_2() {
+        static DATA: [u8; 4] = [0, 0, 0, 0]; // some binary data
+        let table: flatbuffers::Table<'static> = flatbuffers::Table::new(&DATA, 0);
+        // this line should compile:
+        table.get::<&'static str>(0, None);
+    }
+}
+
 #[cfg(test)]
 mod roundtrip_generated_code {
     extern crate flatbuffers;