Merge pull request #21 from bgroenks96/bugfix/callable-struct-signature

Allow callable structs in argument_names

Author: oxinabox

src/method.jl

@@ -92,17 +92,15 @@ function signature(orig_sig::Type{<:Tuple}; extra_hygiene=false)
     return def
 end
 
-
-
 function slot_names(m::Method)
     ci = Base.uncompressed_ast(m)
     return ci.slotnames
 end
 
 function argument_names(m::Method)
     slot_syms = slot_names(m)
-    @assert slot_syms[1] === Symbol("#self#")
-    arg_names = slot_syms[2:m.nargs]  # nargs includes 1 for `#self#`
+    # nargs includes 1 for `#self#` or the function object name;
+    arg_names = slot_syms[2:m.nargs]
     return arg_names
 end
 

test/method.jl

@@ -42,6 +42,10 @@ function only_method(f, typ=Tuple{Vararg{Any}})
     return first(ms)
 end
 
+struct TestCallableStruct end
+(self::TestCallableStruct)(x) = 2x
+(self::TestCallableStruct)(x::T,y::R) where {T,R} = 2x + y
+
 @testset "method.jl: signature" begin
     @testset "Basics" begin
         @test_signature basic1(x) = 2x
@@ -112,6 +116,16 @@ end
         @test_signature ((::T) where T) -> 0   # Anonymous parameter
     end
 
+    @testset "callable structs" begin
+        ms = collect(methods(TestCallableStruct()))
+        sig1 = signature(first(filter(m -> m.nargs == 2, ms)))
+        @test sig1[:name] == :TestCallableStruct
+        @test sig1[:args] == [:x]
+        sig2 = signature(first(filter(m -> m.nargs == 3, ms)))
+        @test sig2[:name] == :TestCallableStruct
+        @test sig2[:args] == Expr[:(x::T),:(y::R)]
+    end
+
     @testset "vararg" begin
         @test_signature f17(xs::Vararg{Any, N} where N) = 2