KeyError: key "Pkg" not found

[timholy]

Here's the setup: fairly fresh build of master (1.1.0-DEV.860 (2018-12-11)), delete .julia/environments/v1.1, do a fresh pull on registries/General, remove our private registry, and start without any startup file:

$ ./julia --startup-file=no
               _
   _       _ _(_)_     |  Documentation: https://docs.julialang.org
  (_)     | (_) (_)    |
   _ _   _| |_  __ _   |  Type "?" for help, "]?" for Pkg help.
  | | | | | | |/ _` |  |
  | | |_| | | | (_| |  |  Version 1.1.0-DEV.860 (2018-12-11)
 _/ |\__'_|_|_|\__'_|  |  Commit 5b2e3e7* (0 days old master)
|__/                   |

(v1.1) pkg> add Example
  Updating registry at `~/.julia/registries/General`
  Updating git-repo `https://github.com/JuliaRegistries/General.git`
 Resolving package versions...
  Updating `~/.julia/environments/v1.1/Project.toml`
  [7876af07] + Example v0.5.1
  Updating `~/.julia/environments/v1.1/Manifest.toml`
  [7876af07] + Example v0.5.1
  [2a0f44e3] + Base64 
  [8ba89e20] + Distributed 
  [b77e0a4c] + InteractiveUtils 
  [56ddb016] + Logging 
  [d6f4376e] + Markdown 
  [9a3f8284] + Random 
  [9e88b42a] + Serialization 
  [6462fe0b] + Sockets 
  [8dfed614] + Test 

(v1.1) pkg> add FixedPointNumbers ColorTypes
 Resolving package versions...
  Updating `~/.julia/environments/v1.1/Project.toml`
  [3da002f7] + ColorTypes v0.7.5
  [53c48c17] + FixedPointNumbers v0.5.3
  Updating `~/.julia/environments/v1.1/Manifest.toml`
  [3da002f7] + ColorTypes v0.7.5
  [53c48c17] + FixedPointNumbers v0.5.3

(v1.1) pkg> add Reexport
 Resolving package versions...
  Updating `~/.julia/environments/v1.1/Project.toml`
  [189a3867] + Reexport v0.2.0
  Updating `~/.julia/environments/v1.1/Manifest.toml`
  [189a3867] + Reexport v0.2.0
  [ade2ca70] + Dates 
  [76f85450] + LibGit2 
  [44cfe95a] + Pkg-f9180e48b27a843aeee864db814dce57cb296b9b 
  [de0858da] + Printf 
  [3fa0cd96] + REPL 
  [ea8e919c] + SHA 
  [cf7118a7] + UUIDs 
  [4ec0a83e] + Unicode 
ERROR: KeyError: key "Pkg" not found
Stacktrace:
 [1] getindex at ./dict.jl:478 [inlined]
 [2] #109 at /home/tim/src/julia-branch/usr/share/julia/stdlib/v1.1/Pkg/src/Types.jl:1504 [inlined]
 [3] _all(::getfield(Pkg.Types, Symbol("##109#111")){Dict{String,Bool}}, ::Dict{String,Base.UUID}, ::Colon) at ./reduce.jl:663
 [4] all at ./reduce.jl:658 [inlined]
 [5] destructure(::Dict{Base.UUID,Pkg.Types.PackageEntry}) at /home/tim/src/julia-branch/usr/share/julia/stdlib/v1.1/Pkg/src/Types.jl:1504
 [6] write_manifest at /home/tim/src/julia-branch/usr/share/julia/stdlib/v1.1/Pkg/src/Types.jl:1545 [inlined]
 [7] #117 at /home/tim/src/julia-branch/usr/share/julia/stdlib/v1.1/Pkg/src/Types.jl:1542 [inlined]
 [8] #open#308(::Base.Iterators.Pairs{Symbol,Bool,Tuple{Symbol},NamedTuple{(:truncate,),Tuple{Bool}}}, ::Function, ::getfield(Pkg.Types, Symbol("##117#118")){Dict{Base.UUID,Pkg.Types.PackageEntry}}, ::String) at ./iostream.jl:369
 [9] #open at ./none:0 [inlined]
 [10] write_manifest at /home/tim/src/julia-branch/usr/share/julia/stdlib/v1.1/Pkg/src/Types.jl:1541 [inlined]
 [11] #write_manifest#119(::Bool, ::Function, ::Dict{Base.UUID,Pkg.Types.PackageEntry}, ::Pkg.Types.EnvCache, ::Pkg.Types.EnvCache, ::Pkg.Types.Context) at /home/tim/src/julia-branch/usr/share/julia/stdlib/v1.1/Pkg/src/Types.jl:1557
 [12] #write_manifest at ./none:0 [inlined]
 [13] #write_env#120 at /home/tim/src/julia-branch/usr/share/julia/stdlib/v1.1/Pkg/src/Types.jl:1564 [inlined]
 [14] write_env at /home/tim/src/julia-branch/usr/share/julia/stdlib/v1.1/Pkg/src/Types.jl:1561 [inlined]
 [15] #add_or_develop#63(::Array{Base.UUID,1}, ::Symbol, ::Function, ::Pkg.Types.Context, ::Array{Pkg.Types.PackageSpec,1}) at /home/tim/src/julia-branch/usr/share/julia/stdlib/v1.1/Pkg/src/Operations.jl:1173
 [16] #add_or_develop at ./none:0 [inlined]
 [17] #add_or_develop#15(::Symbol, ::Bool, ::Base.Iterators.Pairs{Union{},Union{},Tuple{},NamedTuple{(),Tuple{}}}, ::Function, ::Pkg.Types.Context, ::Array{Pkg.Types.PackageSpec,1}) at /home/tim/src/julia-branch/usr/share/julia/stdlib/v1.1/Pkg/src/API.jl:54
 [18] (::getfield(Pkg.API, Symbol("#kw##add_or_develop")))(::NamedTuple{(:mode,),Tuple{Symbol}}, ::typeof(Pkg.API.add_or_develop), ::Pkg.Types.Context, ::Array{Pkg.Types.PackageSpec,1}) at ./none:0
 [19] do_add!(::Dict{Symbol,Any}, ::Array{Pkg.Types.PackageSpec,1}, ::Dict{Symbol,Any}) at /home/tim/src/julia-branch/usr/share/julia/stdlib/v1.1/Pkg/src/REPLMode.jl:659
 [20] #invokelatest#1(::Base.Iterators.Pairs{Union{},Union{},Tuple{},NamedTuple{(),Tuple{}}}, ::Function, ::Any, ::Any, ::Vararg{Any,N} where N) at ./essentials.jl:742
 [21] invokelatest(::Any, ::Any, ::Vararg{Any,N} where N) at ./essentials.jl:741
 [22] do_cmd!(::Pkg.REPLMode.PkgCommand, ::REPL.LineEditREPL) at /home/tim/src/julia-branch/usr/share/julia/stdlib/v1.1/Pkg/src/REPLMode.jl:561
 [23] #do_cmd#30(::Bool, ::Function, ::REPL.LineEditREPL, ::String) at /home/tim/src/julia-branch/usr/share/julia/stdlib/v1.1/Pkg/src/REPLMode.jl:536
 [24] do_cmd at /home/tim/src/julia-branch/usr/share/julia/stdlib/v1.1/Pkg/src/REPLMode.jl:532 [inlined]
 [25] (::getfield(Pkg.REPLMode, Symbol("##48#51")){REPL.LineEditREPL,REPL.LineEdit.Prompt})(::REPL.LineEdit.MIState, ::Base.GenericIOBuffer{Array{UInt8,1}}, ::Bool) at /home/tim/src/julia-branch/usr/share/julia/stdlib/v1.1/Pkg/src/REPLMode.jl:967
 [26] #invokelatest#1 at ./essentials.jl:742 [inlined]
 [27] invokelatest at ./essentials.jl:741 [inlined]
 [28] run_interface(::REPL.Terminals.TextTerminal, ::REPL.LineEdit.ModalInterface, ::REPL.LineEdit.MIState) at /home/tim/src/julia-branch/usr/share/julia/stdlib/v1.1/REPL/src/LineEdit.jl:2273
 [29] run_frontend(::REPL.LineEditREPL, ::REPL.REPLBackendRef) at /home/tim/src/julia-branch/usr/share/julia/stdlib/v1.1/REPL/src/REPL.jl:1035
 [30] run_repl(::REPL.AbstractREPL, ::Any) at /home/tim/src/julia-branch/usr/share/julia/stdlib/v1.1/REPL/src/REPL.jl:192
 [31] (::getfield(Base, Symbol("##732#734")){Bool,Bool,Bool,Bool})(::Module) at ./client.jl:362
 [32] #invokelatest#1 at ./essentials.jl:742 [inlined]
 [33] invokelatest at ./essentials.jl:741 [inlined]
 [34] run_main_repl(::Bool, ::Bool, ::Bool, ::Bool, ::Bool) at ./client.jl:346
 [35] exec_options(::Base.JLOptions) at ./client.jl:284
 [36] _start() at ./client.jl:436

(v1.1) pkg> 

But using Pkg works fine.

I remember seeing an alarming message when I did some kind of update; it was something along the lines of

[some uuid] - Pkg
[some uuid] + Pkg.aks824j1473a

where of course the specific string is just made up junk to convey the spirit of this. Wish I'd copy/pasted the actual events. But this was the beginning of this problem.

[fredrikekre]

You need to clean the usr directory in your repo, c.f. Jameson's comment: JuliaLang/julia#30075 (comment)