julia: add AbstractMXError as parent type (apache#16235)

julia/NEWS.md

@@ -17,6 +17,9 @@
 
 # v1.6.0
 
+* Add an abstract type `AbstractMXError` as the parent type for all MXNet-related
+  API errors. (#16235)
+
 
 # v1.5.0
 

julia/src/MXNet.jl

@@ -43,6 +43,10 @@ import Base.Iterators: filter
 #  exports
 ###############################################################################
 
+# exceptions.jl
+export AbstractMXError,
+       MXError
+
 # symbolic-node.jl
 export SymbolicNode,
        Variable,
@@ -136,6 +140,7 @@ export to_graphviz
 #  includes
 ###############################################################################
 
+include("exceptions.jl")
 include("base.jl")
 
 include("runtime.jl")

julia/src/base.jl

@@ -15,13 +15,6 @@
 # specific language governing permissions and limitations
 # under the License.
 
-"Exception thrown when an error occurred calling MXNet API."
-struct MXError <: Exception
-  msg :: AbstractString
-end
-
-Base.show(io::IO, e::MXError) = print(io, e.msg)
-
 ################################################################################
 # Common types used in MXNet API
 ################################################################################

julia/src/exceptions.jl

@@ -0,0 +1,31 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+
+
+"""
+Exception thrown when an error occurred calling MXNet API.
+"""
+abstract type AbstractMXError <: Exception end
+
+"General MXNet API error"
+struct MXError <: AbstractMXError
+  msg::String
+
+  MXError(s::AbstractString) = new(string(s))
+end
+
+Base.show(io::IO, e::AbstractMXError) = print(io, e.msg)

julia/test/unittest/exceptions.jl

@@ -0,0 +1,42 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+
+module TestExceptions
+
+using MXNet
+using Test
+
+struct MXError′ <: AbstractMXError
+  msg::String
+end
+
+function test_show()
+  @info "AbstractMXError::Base.show"
+
+  io = IOBuffer()
+  e = MXError′("magic")
+  print(io, e)
+  str = String(take!(io))
+  @test str == "magic"
+end
+
+@testset "Exception Test" begin
+  test_show()
+end
+
+
+end  # module TestExceptions