constrain the path argument of include functions to AbstractString

base/loading.jl

@@ -2767,8 +2767,8 @@ function evalfile(path::AbstractString, args::Vector{String}=String[])
         Expr(:toplevel,
              :(const ARGS = $args),
              :(eval(x) = $(Expr(:core, :eval))(__anon__, x)),
-             :(include(x) = $(Expr(:top, :include))(__anon__, x)),
-             :(include(mapexpr::Function, x) = $(Expr(:top, :include))(mapexpr, __anon__, x)),
+             :(include(x::AbstractString) = $(Expr(:top, :include))(__anon__, x)),
+             :(include(mapexpr::Function, x::AbstractString) = $(Expr(:top, :include))(mapexpr, __anon__, x)),
              :(include($path))))
 end
 evalfile(path::AbstractString, args::Vector) = evalfile(path, String[args...])

src/jlfrontend.scm

@@ -211,11 +211,11 @@
           (block
            ,@loc
            (call (core eval) ,name ,x)))
-       (= (call include ,x)
+       (= (call include (:: ,x (top AbstractString)))
           (block
            ,@loc
            (call (core _call_latest) (top include) ,name ,x)))
-       (= (call include (:: ,mex (top Function)) ,x)
+       (= (call include (:: ,mex (top Function)) (:: ,x (top AbstractString)))
           (block
            ,@loc
            (call (core _call_latest) (top include) ,mex ,name ,x)))))

test/loading.jl

@@ -793,6 +793,17 @@ import .Foo28190.Libdl; import Libdl
     end
 end
 
+@testset "`::AbstractString` constraint on the path argument to `include`" begin
+    for m ∈ (NotPkgModule, evalfile("testhelpers/just_module.jl"))
+        let i = m.include
+            @test !applicable(i, (nothing,))
+            @test !applicable(i, (identity, nothing,))
+            @test !hasmethod(i, Tuple{Nothing})
+            @test !hasmethod(i, Tuple{Function,Nothing})
+        end
+    end
+end
+
 @testset "`Base.project_names` and friends" begin
     # Some functions in Pkg assumes that these tuples have the same length
     n = length(Base.project_names)

test/testhelpers/just_module.jl

@@ -0,0 +1 @@
+@__MODULE__