Chaining PlugInstall and PlugUpdate breaks

[xeruf]

I tried to execute PlugInstall | PlugUpdate and had that mapped to a command, because I didn't know that PlugUpdate would also install missing plugins. After adding a new plugin, these two commands apparently break each other and throw everything full of errors.

This is not really a valid usecase, but still thought I might report it.

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NVIM v0.4.3
Build type: Release
LuaJIT 2.1.0-beta3
Compilation: /usr/bin/cc -g -O2 -fdebug-prefix-map=/build/neovim-U5Ub0w/neovim-0.4.3=. -fstack-protector-strong -Wformat -Werror=format-security -Wdate-time -D_FORTIFY_SOURCE=1 -DDISABLE_LOG -Wdate-time -D_FORTIF
Y_SOURCE=1 -O2 -DNDEBUG -DMIN_LOG_LEVEL=3 -Wall -Wextra -pedantic -Wno-unused-parameter -Wstrict-prototypes -std=gnu99 -Wshadow -Wconversion -Wmissing-prototypes -Wimplicit-fallthrough -Wvla -fstack-protector-str
ong -fdiagnostics-color=always -DINCLUDE_GENERATED_DECLARATIONS -D_GNU_SOURCE -DNVIM_MSGPACK_HAS_FLOAT32 -DNVIM_UNIBI_HAS_VAR_FROM -I/build/neovim-U5Ub0w/neovim-0.4.3/build/config -I/build/neovim-U5Ub0w/neovim-0.
4.3/src -I/usr/include -I/usr/include/lua5.1 -I/build/neovim-U5Ub0w/neovim-0.4.3/build/src/nvim/auto -I/build/neovim-U5Ub0w/neovim-0.4.3/build/include
Compiled by [email protected]

• Type:
  • [x] Bug
  • [ ] Enhancement
  • [ ] Feature Request
  • [ ] Question
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[janlazo]

PlugInstall --sync | PlugUpdate --sync

works so it's a matter of setting some flag for vim-plug to do any of the following:

1. Wait for the previous asynchronous Plug command to completely finish
2. Display an error to the user that they should not combine 2 asynchronous commands.

--sync is undocumented and was added in https://github.com/junegunn/vim-plug/commit/5fc9eab788608fb4adcb07a8d79354dcafefaa6a.