Don't use BashLS with Neovim LSP. Use EFM-langserver + shellcheck

config.yaml

version: 2
root-markers:
  - .git/
lint-debounce: 1s
tools:
  sh-shellcheck: &sh-shellcheck
    lint-command: 'shellcheck -f gcc -x'
    lint-source: 'shellcheck'
    lint-formats:
      - '%f:%l:%c: %trror: %m'
      - '%f:%l:%c: %tarning: %m'
      - '%f:%l:%c: %tote: %m'
  sh-shfmt: &sh-shfmt
    format-command: 'shfmt -ci -s -bn'
    format-stdin: true
languages:
  sh:
    - <<: *sh-shellcheck
    - <<: *sh-shfmt

init.lua

require "lspconfig".efm.setup {
    init_options = {documentFormatting = true},
    settings = {
      rootMarkers = {".git/"},
    }
}

install.sh

# BashLS doesn't give you errors/warnings in your .sh files. So use EFM-langserver + shellcheck.
# EFM-langserver checks and lints for various languages. Shellcheck is a binary EFM-langserver
#   uses for .sh files.
# Install GO (programming language) for your OS.
# Then use "go" to install the following:

# =============================================================================        
# EFM-langserver:        
# =============================================================================        
if ! which shfmt ; then        
  go install mvdan.cc/sh/v3/cmd/shfmt@latest        
fi        
if ! which efm-langserver ; then        
  go install github.com/mattn/efm-langserver@latest        
fi        
if ! which gup ; then        
  go install github.com/nao1215/gup@latest        
fi        
gup update # Use this command to update all the binaries you just installed with 'go'.

# Put "config.yaml" (see above) in ~/.config/efm-langserver/

# Make sure you have nvim-lspconfig (https://github.com/neovim/nvim-lspconfig) installed.
# Add the Lua code above. Where it says "require lspconfig.efm.setup..."
# Be sure to get disable "require'lspconfig'.bashls.setup({})" if you have it in your init.lua file.
#   You won't need it for efm-langserver since it replaces BashLS.
# For linux users:
# Run this to keep watching your lsp log file:
watch -n5 tail ~/.cache/nvim/lsp.log
# In Neovim: Open a .sh file. And do :LspInfo
#    This will get you the location of your lsp.log file
#    and other info.  Combine this with the outout of lsp.log
#    and this should be enough to fix any potential problems you have in getting all
#    of this to work. 

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