From c489d565677653df71daf47a238d52a7ae8385f9 Mon Sep 17 00:00:00 2001
From: Tim Holy <tim.holy@gmail.com>
Date: Tue, 6 Oct 2020 04:16:55 -0500
Subject: [PATCH 1/6] WIP: use invoke_in_world to shield Revise from
 self-invalidation

---
 src/legacy_loading.jl | 2 +-
 src/loading.jl        | 2 +-
 src/packagedef.jl     | 8 +++++++-
 src/pkgs.jl           | 4 ++--
 src/utils.jl          | 2 +-
 5 files changed, 12 insertions(+), 6 deletions(-)

diff --git a/src/legacy_loading.jl b/src/legacy_loading.jl
index e310f22f..5a6448f3 100644
--- a/src/legacy_loading.jl
+++ b/src/legacy_loading.jl
@@ -156,7 +156,7 @@ function parse_pkg_files(id::PkgId)
     # To reduce compiler latency, use runtime dispatch for `queue_includes!`.
     # `queue_includes!` requires compilation of the whole parsing/expression-splitting infrastructure,
     # and it's better to wait to compile it until we actually need it.
-    Base.invokelatest(queue_includes!, pkgdata, id)
+    Base.invoke_in_world(worldage[], queue_includes!, pkgdata, id)
     return pkgdata
 end
 
diff --git a/src/loading.jl b/src/loading.jl
index db8d0b22..07649851 100644
--- a/src/loading.jl
+++ b/src/loading.jl
@@ -48,7 +48,7 @@ function parse_pkg_files(id::PkgId)
     # To reduce compiler latency, use runtime dispatch for `queue_includes!`.
     # `queue_includes!` requires compilation of the whole parsing/expression-splitting infrastructure,
     # and it's better to wait to compile it until we actually need it.
-    Base.invokelatest(queue_includes!, pkgdata, id)
+    Base.invoke_in_world(worldage[], queue_includes!, pkgdata, id)
     return pkgdata
 end
 
diff --git a/src/packagedef.jl b/src/packagedef.jl
index 441c25ac..c053b8af 100644
--- a/src/packagedef.jl
+++ b/src/packagedef.jl
@@ -198,6 +198,11 @@ const silence_pkgs = Set{Symbol}()
 const depsdir = joinpath(dirname(@__DIR__), "deps")
 const silencefile = Ref(joinpath(depsdir, "silence.txt"))  # Ref so that tests don't clobber
 
+"""
+    world age
+"""
+const worldage = Ref{Union{Nothing,UInt}}(nothing)
+
 ##
 ## The inputs are sets of expressions found in each file.
 ## Some of those expressions will generate methods which are identified via their signatures.
@@ -1178,7 +1183,7 @@ end
 # This uses invokelatest not for reasons of world age but to ensure that the call is made at runtime.
 # This allows `revise_first` to be compiled without compiling `revise` itself, and greatly
 # reduces the overhead of using Revise.
-revise_first(ex) = Expr(:toplevel, :(isempty($revision_queue) || Base.invokelatest($revise)), ex)
+revise_first(ex) = Expr(:toplevel, :(isempty($revision_queue) || Base.invoke_in_world($(worldage[]), $revise)), ex)
 
 @noinline function run_backend(backend)
     while true
@@ -1277,6 +1282,7 @@ function init_worker(p)
 end
 
 function __init__()
+    worldage[] = Base.get_world_counter()
     run_on_worker = get(ENV, "JULIA_REVISE_WORKER_ONLY", "0")
     if !(myid() == 1 || run_on_worker == "1")
         return nothing
diff --git a/src/pkgs.jl b/src/pkgs.jl
index 3b1cc929..7c7dd6a1 100644
--- a/src/pkgs.jl
+++ b/src/pkgs.jl
@@ -171,7 +171,7 @@ function maybe_add_includes_to_pkgdata!(pkgdata::PkgData, file::AbstractString,
                 parse_source!(fi.modexsigs, fullfile, mod)
                 if eval_now
                     # Use runtime dispatch to reduce latency
-                    Base.invokelatest(instantiate_sigs!, fi.modexsigs; mode=:eval)
+                    Base.invoke_in_world(worldage[], instantiate_sigs!, fi.modexsigs; mode=:eval)
                 end
             end
             # Add to watchlist
@@ -237,7 +237,7 @@ function _add_require(sourcefile, modcaller, idmod, modname, expr)
             end
         end
         if complex
-            Base.invokelatest(eval_require_now, pkgdata, fileidx, filekey, sourcefile, modcaller, expr)
+            Base.invoke_in_world(worldage[], eval_require_now, pkgdata, fileidx, filekey, sourcefile, modcaller, expr)
         end
     finally
         unlock(requires_lock)
diff --git a/src/utils.jl b/src/utils.jl
index ec4aae51..49396899 100644
--- a/src/utils.jl
+++ b/src/utils.jl
@@ -193,7 +193,7 @@ This is used to make stacktraces obtained with Revise more similar to those obta
 without Revise, while retaining one entry to reveal Revise's involvement.
 """
 function trim_toplevel!(bt)
-    # return bt       # uncomment this line if you're debugging Revise itself
+    return bt
     n = itoplevel = length(bt)
     for (i, t) in enumerate(bt)
         sfs = StackTraces.lookup(t)

From 51a768cd7be2feeea5b2fafcbe67d898218d98b5 Mon Sep 17 00:00:00 2001
From: Simeon Schaub <simeondavidschaub99@gmail.com>
Date: Wed, 7 Oct 2020 14:27:17 +0200
Subject: [PATCH 2/6] use correct worldage in lowering and remotecall

---
 src/lowered.jl    |  4 +++-
 src/packagedef.jl | 11 +++++++----
 2 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/src/lowered.jl b/src/lowered.jl
index e754c6bb..d3812e63 100644
--- a/src/lowered.jl
+++ b/src/lowered.jl
@@ -128,6 +128,8 @@ function methods_by_execution(mod::Module, ex::Expr; kwargs...)
     return methodinfo, docexprs, frame
 end
 
+_lower(m::Module, ex, world::UInt) = ccall(:jl_expand_in_world, Any, (Any, Module, Cstring, Cint, Csize_t), ex, m, "none", 0, world)
+
 """
     methods_by_execution!(recurse=JuliaInterpreter.Compiled(), methodinfo, docexprs, mod::Module, ex::Expr;
                           mode=:eval, disablebp=true, skip_include=mode!==:eval, always_rethrow=false)
@@ -175,7 +177,7 @@ The other keyword arguments are more straightforward:
 function methods_by_execution!(@nospecialize(recurse), methodinfo, docexprs, mod::Module, ex::Expr;
                                mode::Symbol=:eval, disablebp::Bool=true, always_rethrow::Bool=false, kwargs...)
     mode ∈ (:sigs, :eval, :evalmeth, :evalassign) || error("unsupported mode ", mode)
-    lwr = Meta.lower(mod, ex)
+    lwr = _lower(mod, ex, worldage[])
     isa(lwr, Expr) || return nothing, nothing
     if lwr.head === :error || lwr.head === :incomplete
         error("lowering returned an error, ", lwr)
diff --git a/src/packagedef.jl b/src/packagedef.jl
index c053b8af..0ed0b735 100644
--- a/src/packagedef.jl
+++ b/src/packagedef.jl
@@ -267,10 +267,13 @@ function delete_missing!(exs_sigs_old::ExprsSigs, exs_sigs_new)
                         @debug "DeleteMethod" _group="Action" time=time() deltainfo=(sig, MethodSummary(m))
                         # Delete the corresponding methods
                         for p in workers()
-                            try  # guard against serialization errors if the type isn't defined on the worker
-                                remotecall(Core.eval, p, Main, :(delete_method_by_sig($sig)))
-                            catch
-                            end
+                            #try  # guard against serialization errors if the type isn't defined on the worker
+                                future = remotecall(Core.eval, p, Main, :(delete_method_by_sig($sig)))
+                                finalizer(future) do f
+                                    Base.invoke_in_world(worldage[], Distributed.finalize_ref, f)
+                                end
+                            #catch
+                            #end
                         end
                         Base.delete_method(m)
                         # Remove the entries from CodeTracking data

From bd361c4172c8c92bb43a97b1e55ab491442bc1c8 Mon Sep 17 00:00:00 2001
From: Simeon Schaub <simeondavidschaub99@gmail.com>
Date: Fri, 9 Oct 2020 14:54:45 +0200
Subject: [PATCH 3/6] make compatible with all Julia versions

---
 src/legacy_loading.jl |  2 +-
 src/loading.jl        |  2 +-
 src/packagedef.jl     | 24 +++++++++++++++++++++---
 test/runtests.jl      |  2 ++
 4 files changed, 25 insertions(+), 5 deletions(-)

diff --git a/src/legacy_loading.jl b/src/legacy_loading.jl
index 5a6448f3..e48e844e 100644
--- a/src/legacy_loading.jl
+++ b/src/legacy_loading.jl
@@ -156,7 +156,7 @@ function parse_pkg_files(id::PkgId)
     # To reduce compiler latency, use runtime dispatch for `queue_includes!`.
     # `queue_includes!` requires compilation of the whole parsing/expression-splitting infrastructure,
     # and it's better to wait to compile it until we actually need it.
-    Base.invoke_in_world(worldage[], queue_includes!, pkgdata, id)
+    invoke_revisefunc(worldage[], queue_includes!, pkgdata, id)
     return pkgdata
 end
 
diff --git a/src/loading.jl b/src/loading.jl
index 07649851..4dcd8072 100644
--- a/src/loading.jl
+++ b/src/loading.jl
@@ -48,7 +48,7 @@ function parse_pkg_files(id::PkgId)
     # To reduce compiler latency, use runtime dispatch for `queue_includes!`.
     # `queue_includes!` requires compilation of the whole parsing/expression-splitting infrastructure,
     # and it's better to wait to compile it until we actually need it.
-    Base.invoke_in_world(worldage[], queue_includes!, pkgdata, id)
+    invoke_revisefunc(worldage[], queue_includes!, pkgdata, id)
     return pkgdata
 end
 
diff --git a/src/packagedef.jl b/src/packagedef.jl
index 0ed0b735..23f93aef 100644
--- a/src/packagedef.jl
+++ b/src/packagedef.jl
@@ -199,7 +199,10 @@ const depsdir = joinpath(dirname(@__DIR__), "deps")
 const silencefile = Ref(joinpath(depsdir, "silence.txt"))  # Ref so that tests don't clobber
 
 """
-    world age
+    Revise.worldage
+
+The world age Revise was started in. Needed so that Revise doesn't delete methods
+from under itself.
 """
 const worldage = Ref{Union{Nothing,UInt}}(nothing)
 
@@ -270,7 +273,7 @@ function delete_missing!(exs_sigs_old::ExprsSigs, exs_sigs_new)
                             #try  # guard against serialization errors if the type isn't defined on the worker
                                 future = remotecall(Core.eval, p, Main, :(delete_method_by_sig($sig)))
                                 finalizer(future) do f
-                                    Base.invoke_in_world(worldage[], Distributed.finalize_ref, f)
+                                    Base.invoke_revisefunc(worldage[], Distributed.finalize_ref, f)
                                 end
                             #catch
                             #end
@@ -1182,11 +1185,26 @@ function maybe_set_prompt_color(color)
     return nothing
 end
 
+if VERSION < v"1.6.0-DEV.1162"
+    const invoke_revisefunc = Base.invokelatest
+    const lower_in_reviseworld = Meta.lower
+else
+    function invoke_revisefunc(f, args...; kwargs...)
+        return Base.invoke_in_world(worldage[], f, args...; kwargs...)
+    end
+    function lower_in_reviseworld(m::Module, @nospecialize(ex))
+        return ccall(:jl_expand_in_world, Any,
+            (Any, Ref{Module}, Cstring, Cint, Csize_t),
+            ex, m, "none", 0, world,
+        )
+    end
+end
+
 # On Julia 1.5.0-DEV.282 and higher, we can just use an AST transformation
 # This uses invokelatest not for reasons of world age but to ensure that the call is made at runtime.
 # This allows `revise_first` to be compiled without compiling `revise` itself, and greatly
 # reduces the overhead of using Revise.
-revise_first(ex) = Expr(:toplevel, :(isempty($revision_queue) || Base.invoke_in_world($(worldage[]), $revise)), ex)
+revise_first(ex) = Expr(:toplevel, :(isempty($revision_queue) || Base.invoke_revisefunc($revise)), ex)
 
 @noinline function run_backend(backend)
     while true
diff --git a/test/runtests.jl b/test/runtests.jl
index 0ac3bb9d..cf43d544 100644
--- a/test/runtests.jl
+++ b/test/runtests.jl
@@ -4,6 +4,8 @@ using Revise.CodeTracking
 using Revise.JuliaInterpreter
 using Test
 
+@show VERSION
+
 @test isempty(detect_ambiguities(Revise))
 
 using Pkg, Unicode, Distributed, InteractiveUtils, REPL, UUIDs

From ba5e6ca96e6b4094cab85a65ffcf7d92037288bf Mon Sep 17 00:00:00 2001
From: Simeon Schaub <simeondavidschaub99@gmail.com>
Date: Sat, 10 Oct 2020 11:32:08 +0200
Subject: [PATCH 4/6] wip

---
 src/legacy_loading.jl | 3 ++-
 src/loading.jl        | 3 ++-
 src/packagedef.jl     | 8 ++++----
 3 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/src/legacy_loading.jl b/src/legacy_loading.jl
index e48e844e..e74b9bc2 100644
--- a/src/legacy_loading.jl
+++ b/src/legacy_loading.jl
@@ -156,7 +156,8 @@ function parse_pkg_files(id::PkgId)
     # To reduce compiler latency, use runtime dispatch for `queue_includes!`.
     # `queue_includes!` requires compilation of the whole parsing/expression-splitting infrastructure,
     # and it's better to wait to compile it until we actually need it.
-    invoke_revisefunc(worldage[], queue_includes!, pkgdata, id)
+    worldage[] = Base.get_world_counter()
+    invoke_revisefunc(queue_includes!, pkgdata, id)
     return pkgdata
 end
 
diff --git a/src/loading.jl b/src/loading.jl
index 4dcd8072..c2c44a14 100644
--- a/src/loading.jl
+++ b/src/loading.jl
@@ -48,7 +48,8 @@ function parse_pkg_files(id::PkgId)
     # To reduce compiler latency, use runtime dispatch for `queue_includes!`.
     # `queue_includes!` requires compilation of the whole parsing/expression-splitting infrastructure,
     # and it's better to wait to compile it until we actually need it.
-    invoke_revisefunc(worldage[], queue_includes!, pkgdata, id)
+    worldage[] = Base.get_world_counter()
+    invoke_revisefunc(queue_includes!, pkgdata, id)
     return pkgdata
 end
 
diff --git a/src/packagedef.jl b/src/packagedef.jl
index 23f93aef..792d4757 100644
--- a/src/packagedef.jl
+++ b/src/packagedef.jl
@@ -273,7 +273,7 @@ function delete_missing!(exs_sigs_old::ExprsSigs, exs_sigs_new)
                             #try  # guard against serialization errors if the type isn't defined on the worker
                                 future = remotecall(Core.eval, p, Main, :(delete_method_by_sig($sig)))
                                 finalizer(future) do f
-                                    Base.invoke_revisefunc(worldage[], Distributed.finalize_ref, f)
+                                    invoke_revisefunc(Distributed.finalize_ref, f)
                                 end
                             #catch
                             #end
@@ -1204,7 +1204,7 @@ end
 # This uses invokelatest not for reasons of world age but to ensure that the call is made at runtime.
 # This allows `revise_first` to be compiled without compiling `revise` itself, and greatly
 # reduces the overhead of using Revise.
-revise_first(ex) = Expr(:toplevel, :(isempty($revision_queue) || Base.invoke_revisefunc($revise)), ex)
+revise_first(ex) = Expr(:toplevel, :(isempty($revision_queue) || (worldage[] = Base.get_world_counter(); invoke_revisefunc($revise))), ex)
 
 @noinline function run_backend(backend)
     while true
@@ -1355,8 +1355,8 @@ function __init__()
     id = PkgId(nothing, "@REPL")
     pkgdatas[id] = pkgdata = PkgData(id, nothing)
     # Set the lookup callbacks
-    CodeTracking.method_lookup_callback[] = get_def
-    CodeTracking.expressions_callback[] = get_expressions
+    CodeTracking.method_lookup_callback[] = x -> (worldage[] = Base.get_world_counter(); invoke_revisefunc(get_def, x))
+    CodeTracking.expressions_callback[] = x -> (worldage[] = Base.get_world_counter(); invoke_revisefunc(get_expressions, x))
 
     # Watch the manifest file for changes
     mfile = manifest_file()

From eb51a57f0c4221736fa36752599c3eb44327c572 Mon Sep 17 00:00:00 2001
From: Simeon Schaub <simeondavidschaub99@gmail.com>
Date: Sat, 10 Oct 2020 23:55:57 +0200
Subject: [PATCH 5/6] foo

---
 Project.toml      |  3 ++-
 src/packagedef.jl | 21 +++++++++++++--------
 test/runtests.jl  |  4 ++--
 3 files changed, 17 insertions(+), 11 deletions(-)

diff --git a/Project.toml b/Project.toml
index 3a2cfb7a..b4c41bf9 100644
--- a/Project.toml
+++ b/Project.toml
@@ -29,6 +29,7 @@ Base64 = "2a0f44e3-6c83-55bd-87e4-b1978d98bd5f"
 CRC32c = "8bf52ea8-c179-5cab-976a-9e18b702a9bc"
 CatIndices = "aafaddc9-749c-510e-ac4f-586e18779b91"
 Dates = "ade2ca70-3891-5945-98fb-dc099432e06a"
+Debugger = "31a5f54b-26ea-5ae9-a837-f05ce5417438"
 DelimitedFiles = "8bb1440f-4735-579b-a4ab-409b98df4dab"
 EndpointRanges = "340492b5-2a47-5f55-813d-aca7ddf97656"
 EponymTuples = "97e2ac4a-e175-5f49-beb1-4d6866a6cdc3"
@@ -57,4 +58,4 @@ SuiteSparse = "4607b0f0-06f3-5cda-b6b1-a6196a1729e9"
 Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
 
 [targets]
-test = ["Test", "Base64", "CRC32c", "CatIndices", "Dates", "DelimitedFiles", "EndpointRanges", "EponymTuples", "Example", "Future", "IndirectArrays", "InteractiveUtils", "Libdl", "LinearAlgebra", "Logging", "MappedArrays", "Markdown", "Mmap", "Printf", "Profile", "Random", "Requires", "RoundingIntegers", "SHA", "Serialization", "SharedArrays", "Sockets", "SparseArrays", "Statistics", "SuiteSparse"]
+test = ["Test", "Base64", "CRC32c", "CatIndices", "Dates", "DelimitedFiles", "EndpointRanges", "EponymTuples", "Example", "Future", "IndirectArrays", "InteractiveUtils", "Libdl", "LinearAlgebra", "Logging", "MappedArrays", "Markdown", "Mmap", "Printf", "Profile", "Random", "Requires", "RoundingIntegers", "SHA", "Serialization", "SharedArrays", "Sockets", "SparseArrays", "Statistics", "SuiteSparse", "Debugger"]
diff --git a/src/packagedef.jl b/src/packagedef.jl
index 792d4757..2c9e9c0e 100644
--- a/src/packagedef.jl
+++ b/src/packagedef.jl
@@ -198,13 +198,14 @@ const silence_pkgs = Set{Symbol}()
 const depsdir = joinpath(dirname(@__DIR__), "deps")
 const silencefile = Ref(joinpath(depsdir, "silence.txt"))  # Ref so that tests don't clobber
 
-"""
-    Revise.worldage
-
-The world age Revise was started in. Needed so that Revise doesn't delete methods
-from under itself.
-"""
-const worldage = Ref{Union{Nothing,UInt}}(nothing)
+#"""
+#    Revise.worldage
+#
+#The world age Revise was started in. Needed so that Revise doesn't delete methods
+#from under itself.
+#"""
+#const worldage = Ref{Union{Nothing,UInt}}(nothing)
+using CodeTracking: worldage
 
 ##
 ## The inputs are sets of expressions found in each file.
@@ -1190,12 +1191,16 @@ if VERSION < v"1.6.0-DEV.1162"
     const lower_in_reviseworld = Meta.lower
 else
     function invoke_revisefunc(f, args...; kwargs...)
+        @show worldage[]
+        Base.show_backtrace(backtrace[1:2])
         return Base.invoke_in_world(worldage[], f, args...; kwargs...)
     end
     function lower_in_reviseworld(m::Module, @nospecialize(ex))
+        @show worldage[]
+        Base.show_backtrace(backtrace[1:2])
         return ccall(:jl_expand_in_world, Any,
             (Any, Ref{Module}, Cstring, Cint, Csize_t),
-            ex, m, "none", 0, world,
+            ex, m, "none", 0, worldage[],
         )
     end
 end
diff --git a/test/runtests.jl b/test/runtests.jl
index cf43d544..0ff759c9 100644
--- a/test/runtests.jl
+++ b/test/runtests.jl
@@ -473,8 +473,8 @@ end
                 @eval @test $(fn4)() == 4
                 @eval @test $(fn5)() == 5
                 @eval @test $(fn6)() == 6
-                m = @eval first(methods($fn1))
-                rex = Revise.RelocatableExpr(definition(m))
+                m = @show @eval first(methods($fn1))
+                rex = Revise.RelocatableExpr(@show definition(m))
                 @test rex == Revise.RelocatableExpr(:( $fn1() = 1 ))
                 # Check that definition returns copies
                 rex2 = deepcopy(rex)

From 210c22080f8d2da32b5ae44865a39b5f15ec4eb8 Mon Sep 17 00:00:00 2001
From: Simeon Schaub <simeondavidschaub99@gmail.com>
Date: Sun, 11 Oct 2020 13:13:04 +0200
Subject: [PATCH 6/6] wip

---
 Project.toml          |  3 +--
 src/legacy_loading.jl |  2 +-
 src/loading.jl        |  1 -
 src/lowered.jl        |  2 +-
 src/packagedef.jl     | 35 ++++++++++++++++++++++-------------
 src/pkgs.jl           |  6 ++++--
 test/runtests.jl      |  6 ++----
 7 files changed, 31 insertions(+), 24 deletions(-)

diff --git a/Project.toml b/Project.toml
index b4c41bf9..3a2cfb7a 100644
--- a/Project.toml
+++ b/Project.toml
@@ -29,7 +29,6 @@ Base64 = "2a0f44e3-6c83-55bd-87e4-b1978d98bd5f"
 CRC32c = "8bf52ea8-c179-5cab-976a-9e18b702a9bc"
 CatIndices = "aafaddc9-749c-510e-ac4f-586e18779b91"
 Dates = "ade2ca70-3891-5945-98fb-dc099432e06a"
-Debugger = "31a5f54b-26ea-5ae9-a837-f05ce5417438"
 DelimitedFiles = "8bb1440f-4735-579b-a4ab-409b98df4dab"
 EndpointRanges = "340492b5-2a47-5f55-813d-aca7ddf97656"
 EponymTuples = "97e2ac4a-e175-5f49-beb1-4d6866a6cdc3"
@@ -58,4 +57,4 @@ SuiteSparse = "4607b0f0-06f3-5cda-b6b1-a6196a1729e9"
 Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
 
 [targets]
-test = ["Test", "Base64", "CRC32c", "CatIndices", "Dates", "DelimitedFiles", "EndpointRanges", "EponymTuples", "Example", "Future", "IndirectArrays", "InteractiveUtils", "Libdl", "LinearAlgebra", "Logging", "MappedArrays", "Markdown", "Mmap", "Printf", "Profile", "Random", "Requires", "RoundingIntegers", "SHA", "Serialization", "SharedArrays", "Sockets", "SparseArrays", "Statistics", "SuiteSparse", "Debugger"]
+test = ["Test", "Base64", "CRC32c", "CatIndices", "Dates", "DelimitedFiles", "EndpointRanges", "EponymTuples", "Example", "Future", "IndirectArrays", "InteractiveUtils", "Libdl", "LinearAlgebra", "Logging", "MappedArrays", "Markdown", "Mmap", "Printf", "Profile", "Random", "Requires", "RoundingIntegers", "SHA", "Serialization", "SharedArrays", "Sockets", "SparseArrays", "Statistics", "SuiteSparse"]
diff --git a/src/legacy_loading.jl b/src/legacy_loading.jl
index e74b9bc2..725f3496 100644
--- a/src/legacy_loading.jl
+++ b/src/legacy_loading.jl
@@ -156,7 +156,7 @@ function parse_pkg_files(id::PkgId)
     # To reduce compiler latency, use runtime dispatch for `queue_includes!`.
     # `queue_includes!` requires compilation of the whole parsing/expression-splitting infrastructure,
     # and it's better to wait to compile it until we actually need it.
-    worldage[] = Base.get_world_counter()
+    #worldage[] = Base.get_world_counter()
     invoke_revisefunc(queue_includes!, pkgdata, id)
     return pkgdata
 end
diff --git a/src/loading.jl b/src/loading.jl
index c2c44a14..79b7b7d7 100644
--- a/src/loading.jl
+++ b/src/loading.jl
@@ -48,7 +48,6 @@ function parse_pkg_files(id::PkgId)
     # To reduce compiler latency, use runtime dispatch for `queue_includes!`.
     # `queue_includes!` requires compilation of the whole parsing/expression-splitting infrastructure,
     # and it's better to wait to compile it until we actually need it.
-    worldage[] = Base.get_world_counter()
     invoke_revisefunc(queue_includes!, pkgdata, id)
     return pkgdata
 end
diff --git a/src/lowered.jl b/src/lowered.jl
index d3812e63..bbc65010 100644
--- a/src/lowered.jl
+++ b/src/lowered.jl
@@ -177,7 +177,7 @@ The other keyword arguments are more straightforward:
 function methods_by_execution!(@nospecialize(recurse), methodinfo, docexprs, mod::Module, ex::Expr;
                                mode::Symbol=:eval, disablebp::Bool=true, always_rethrow::Bool=false, kwargs...)
     mode ∈ (:sigs, :eval, :evalmeth, :evalassign) || error("unsupported mode ", mode)
-    lwr = _lower(mod, ex, worldage[])
+    lwr = lower_in_reviseworld(mod, ex)
     isa(lwr, Expr) || return nothing, nothing
     if lwr.head === :error || lwr.head === :incomplete
         error("lowering returned an error, ", lwr)
diff --git a/src/packagedef.jl b/src/packagedef.jl
index 2c9e9c0e..8526b067 100644
--- a/src/packagedef.jl
+++ b/src/packagedef.jl
@@ -198,14 +198,14 @@ const silence_pkgs = Set{Symbol}()
 const depsdir = joinpath(dirname(@__DIR__), "deps")
 const silencefile = Ref(joinpath(depsdir, "silence.txt"))  # Ref so that tests don't clobber
 
-#"""
-#    Revise.worldage
-#
-#The world age Revise was started in. Needed so that Revise doesn't delete methods
-#from under itself.
-#"""
-#const worldage = Ref{Union{Nothing,UInt}}(nothing)
-using CodeTracking: worldage
+"""
+    Revise.worldage
+
+The world age Revise was started in. Needed so that Revise doesn't delete methods
+from under itself.
+"""
+const worldage = Ref{Union{Nothing,UInt}}(nothing)
+#using CodeTracking: worldage
 
 ##
 ## The inputs are sets of expressions found in each file.
@@ -639,6 +639,7 @@ function handle_deletions(pkgdata, file)
     topmod = first(keys(mexsold))
     fileok = file_exists(filep)
     mexsnew = fileok ? parse_source(filep, topmod) : ModuleExprsSigs(topmod)
+    worldage[] = Base.get_world_counter()
     if mexsnew !== nothing
         delete_missing!(mexsold, mexsnew)
     end
@@ -732,6 +733,7 @@ function revise(; throw=false)
 
     # Do all the deletion first. This ensures that a method that moved from one file to another
     # won't get redefined first and deleted second.
+    @show worldage[] = Base.get_world_counter()
     revision_errors = []
     queue = sort!(collect(revision_queue); lt=pkgfileless)
     finished = eltype(revision_queue)[]
@@ -764,6 +766,7 @@ function revise(; throw=false)
                 mode ∈ (:sigs, :eval, :evalmeth, :evalassign) || error("unsupported mode ", mode)
                 exsold = get(fi.modexsigs, mod, empty_exs_sigs)
                 for rex in keys(exsnew)
+                    @show Base.get_world_counter()
                     sigs, includes = eval_rex(rex, exsold, mod; mode=mode)
                     if sigs !== nothing
                         exsnew[rex] = sigs
@@ -1191,13 +1194,17 @@ if VERSION < v"1.6.0-DEV.1162"
     const lower_in_reviseworld = Meta.lower
 else
     function invoke_revisefunc(f, args...; kwargs...)
-        @show worldage[]
-        Base.show_backtrace(backtrace[1:2])
+        #@show worldage[]
+        #@show Base.get_world_counter()
+        #Base.show_backtrace(stdout, backtrace()[1:4])
+        #println()
         return Base.invoke_in_world(worldage[], f, args...; kwargs...)
     end
     function lower_in_reviseworld(m::Module, @nospecialize(ex))
-        @show worldage[]
-        Base.show_backtrace(backtrace[1:2])
+        #@show worldage[]
+        #@show Base.get_world_counter()
+        #Base.show_backtrace(stdout, backtrace()[1:1])
+        #println()
         return ccall(:jl_expand_in_world, Any,
             (Any, Ref{Module}, Cstring, Cint, Csize_t),
             ex, m, "none", 0, worldage[],
@@ -1209,7 +1216,7 @@ end
 # This uses invokelatest not for reasons of world age but to ensure that the call is made at runtime.
 # This allows `revise_first` to be compiled without compiling `revise` itself, and greatly
 # reduces the overhead of using Revise.
-revise_first(ex) = Expr(:toplevel, :(isempty($revision_queue) || (worldage[] = Base.get_world_counter(); invoke_revisefunc($revise))), ex)
+revise_first(ex) = Expr(:toplevel, :(isempty($revision_queue) || (#=worldage[] = Base.get_world_counter(); =#invoke_revisefunc($revise))), ex)
 
 @noinline function run_backend(backend)
     while true
@@ -1362,6 +1369,8 @@ function __init__()
     # Set the lookup callbacks
     CodeTracking.method_lookup_callback[] = x -> (worldage[] = Base.get_world_counter(); invoke_revisefunc(get_def, x))
     CodeTracking.expressions_callback[] = x -> (worldage[] = Base.get_world_counter(); invoke_revisefunc(get_expressions, x))
+    CodeTracking.method_lookup_callback[] = get_def
+    CodeTracking.expressions_callback[] = get_expressions
 
     # Watch the manifest file for changes
     mfile = manifest_file()
diff --git a/src/pkgs.jl b/src/pkgs.jl
index 7c7dd6a1..15df6157 100644
--- a/src/pkgs.jl
+++ b/src/pkgs.jl
@@ -171,7 +171,8 @@ function maybe_add_includes_to_pkgdata!(pkgdata::PkgData, file::AbstractString,
                 parse_source!(fi.modexsigs, fullfile, mod)
                 if eval_now
                     # Use runtime dispatch to reduce latency
-                    Base.invoke_in_world(worldage[], instantiate_sigs!, fi.modexsigs; mode=:eval)
+                    #Base.invoke_in_world(worldage[], instantiate_sigs!, fi.modexsigs; mode=:eval)
+                    Base.invokelatest(instantiate_sigs!, fi.modexsigs; mode=:eval)
                 end
             end
             # Add to watchlist
@@ -237,7 +238,8 @@ function _add_require(sourcefile, modcaller, idmod, modname, expr)
             end
         end
         if complex
-            Base.invoke_in_world(worldage[], eval_require_now, pkgdata, fileidx, filekey, sourcefile, modcaller, expr)
+            #Base.invoke_in_world(worldage[], eval_require_now, pkgdata, fileidx, filekey, sourcefile, modcaller, expr)
+            Base.invokelatest(eval_require_now, pkgdata, fileidx, filekey, sourcefile, modcaller, expr)
         end
     finally
         unlock(requires_lock)
diff --git a/test/runtests.jl b/test/runtests.jl
index 0ff759c9..0ac3bb9d 100644
--- a/test/runtests.jl
+++ b/test/runtests.jl
@@ -4,8 +4,6 @@ using Revise.CodeTracking
 using Revise.JuliaInterpreter
 using Test
 
-@show VERSION
-
 @test isempty(detect_ambiguities(Revise))
 
 using Pkg, Unicode, Distributed, InteractiveUtils, REPL, UUIDs
@@ -473,8 +471,8 @@ end
                 @eval @test $(fn4)() == 4
                 @eval @test $(fn5)() == 5
                 @eval @test $(fn6)() == 6
-                m = @show @eval first(methods($fn1))
-                rex = Revise.RelocatableExpr(@show definition(m))
+                m = @eval first(methods($fn1))
+                rex = Revise.RelocatableExpr(definition(m))
                 @test rex == Revise.RelocatableExpr(:( $fn1() = 1 ))
                 # Check that definition returns copies
                 rex2 = deepcopy(rex)