From 94ba5427f3d06cc95b208758f2e6ff90947cea2d Mon Sep 17 00:00:00 2001
From: Simeon Schaub <simeondavidschaub99@gmail.com>
Date: Thu, 22 Apr 2021 12:52:25 +0200
Subject: [PATCH] fix #476: isdefined with QuoteNode (#477)

---
 src/interpret.jl  |  5 ++++-
 test/interpret.jl | 12 ++++++++++++
 2 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/src/interpret.jl b/src/interpret.jl
index ba26275a7582c4..23c945a2da89c4 100644
--- a/src/interpret.jl
+++ b/src/interpret.jl
@@ -415,14 +415,17 @@ function check_isdefined(frame, @nospecialize(node))
     data = frame.framedata
     if isa(node, SlotNumber)
         return data.locals[node.id] !== nothing
+    elseif isa(node, Core.Compiler.Argument) # just to be safe, since base handles this
+        return data.locals[node.n] !== nothing
     elseif isexpr(node, :static_parameter)
         return isassigned(data.sparams, node.args[1]::Int)
     elseif isa(node, GlobalRef)
         return isdefined(node.mod, node.name)
     elseif isa(node, Symbol)
         return isdefined(moduleof(frame), node)
+    else # QuoteNode or other implicitly quoted object
+        return true
     end
-    error("unrecognized isdefined node ", node)
 end
 
 # For "profiling" where JuliaInterpreter spends its time. See the commented-out block
diff --git a/test/interpret.jl b/test/interpret.jl
index b5619f3e5d1691..b6ac1368333319 100644
--- a/test/interpret.jl
+++ b/test/interpret.jl
@@ -746,3 +746,15 @@ end
 @testset "#466 parametric_type_to_expr" begin
     @test JuliaInterpreter.parametric_type_to_expr(Array) == :(Core.Array{T, N})
 end
+
+@testset "#476 isdefined QuoteNode" begin
+    f() = !true
+
+    @generated function g()
+        ci = @code_lowered f()
+        ci.code[1] = Expr(:isdefined, QuoteNode(Float64))
+        return ci
+    end
+
+    @test @interpret(g()) === true
+end