Slightly improve handling of kwcall definition lookup failure (#147)

* Improve handling of kwcall definition failure

* Bump version

* Add test for `kwcall` handling failure

Author: serenity4

Project.toml

@@ -1,7 +1,7 @@
 name = "CodeTracking"
 uuid = "da1fd8a2-8d9e-5ec2-8556-3022fb5608a2"
 authors = ["Tim Holy <[email protected]>"]
-version = "2.0.0"
+version = "2.0.1"
 
 [deps]
 InteractiveUtils = "b77e0a4c-d291-57a0-90e8-8db25a27a240"

src/CodeTracking.jl

@@ -229,6 +229,7 @@ function definition(::Type{String}, method::Method)
         p = Base.unwrap_unionall(method.sig).parameters
         for i = 2:length(p)
             T = p[i]
+            isa(T, Core.TypeofVararg) && break # it's not our target, and there are no more arguments after this
             if T <: Function
                 mstring = string(nameof(T))
                 if startswith(mstring, '#')
@@ -237,7 +238,7 @@ function definition(::Type{String}, method::Method)
                 end
             end
         end
-        methodname == :kwcall && error("could not identify method name in `Core.kwcall`")
+        methodname == :kwcall && error("could not identify method name in `Core.kwcall` (signature: $(method.sig))")
     end
     file, line = whereis(method)
     line == 0 && return nothing

test/runtests.jl

@@ -292,6 +292,11 @@ isdefined(Main, :Revise) ? Main.Revise.includet("script.jl") : include("script.j
     src, line = definition(String, m)
     @test occursin("::Type{P}", src)
     @test line == 148
+
+    # Graceful handling of `kwcall` definition lookup failure
+    m = @which Core.kwcall(NamedTuple(), Union{})
+    @test_throws "could not identify method name in `Core.kwcall`" definition(String, m)
+    @test_throws "signature: Tuple{typeof(Core.kwcall), Any, Type{Union{}}, Vararg{Any}}" definition(String, m)
 end
 
 @testset "With Revise" begin