treewide: do not overwrite lsp-client-settings changed by user

If a user has set a setting inside `lsp-client-settings`, changing its
value will result in a silent bug in user configuration that looks
like a regression from `lsp-mode` mode update. Let's avoid that by
adding a new function `lsp-register-new-settings` that avoids
overwritting whatever was set by user and make use of it treewide.

While at it, prohibit `lsp-register-custom-settings` from internal use
for all the same reasons.

Fixes: #4420

Author: Hi-Angel

.github/workflows/lint.yml

@@ -20,6 +20,11 @@ jobs:
         with:
           version: 'snapshot'
 
+      # `lsp-register-custom-settings` should not be used for defining client
+      # settings, see its description for details
+      - name: Do not overwrite user settings
+        run: "! git grep lsp-register-custom-settings -- clients"
+
       - name: Resolve dependency
         run: eask install-deps --dev
 

clients/lsp-ansible.el

@@ -188,7 +188,7 @@ Python virtual environment."
                 '(:npm :package "@ansible/ansible-language-server"
                        :path "ansible-language-server"))
 
-(lsp-register-custom-settings
+(lsp-register-new-settings
  '(("ansible.ansible.path" lsp-ansible-ansible-path)
    ("ansible.ansible.useFullyQualifiedCollectionNames" lsp-ansible-use-fully-qualified-collection-names t)
    ("ansible.validation.enabled" lsp-ansible-validation-enabled t)

clients/lsp-css.el

@@ -198,7 +198,7 @@ server."
           (const "messages")
           (const "verbose")))
 
-(lsp-register-custom-settings
+(lsp-register-new-settings
  '(("css.trace.server" lsp-css-trace-server)
    ("css.lint.unknownAtRules" lsp-css-lint-unknown-at-rules)
    ("css.lint.idSelector" lsp-css-lint-id-selector)

clients/lsp-elixir.el

@@ -169,7 +169,7 @@ be available here: https://github.com/elixir-lsp/elixir-ls/releases/"
              :binary-path lsp-elixir-server-command
              :set-executable? t))
 
-(lsp-register-custom-settings
+(lsp-register-new-settings
  '(("elixirLS.dialyzerEnabled" lsp-elixir-dialyzer-enabled t)
    ("elixirLS.dialyzerWarnOpts" lsp-elixir-dialyzer-warn-opts)
    ("elixirLS.dialyzerFormat" lsp-elixir-dialyzer-format)

clients/lsp-fsharp.el

@@ -249,7 +249,7 @@ available, else the globally installed tool."
         (push '(:AutomaticWorkspaceInit . t) opts)
       opts)))
 
-(lsp-register-custom-settings
+(lsp-register-new-settings
  `(("FSharp.KeywordsAutocomplete" lsp-fsharp-keywords-autocomplete t)
    ("FSharp.ExternalAutocomplete" lsp-fsharp-external-autocomplete t)
    ("FSharp.Linter" lsp-fsharp-linter t)

clients/lsp-go.el

@@ -301,7 +301,7 @@ $GOPATH/pkg/mod along with the value of
   :risky t
   :package-version '(lsp-mode "8.0.0"))
 
-(lsp-register-custom-settings
+(lsp-register-new-settings
  '(("gopls.usePlaceholders" lsp-go-use-placeholders t)
    ("gopls.hoverKind" lsp-go-hover-kind)
    ("gopls.buildFlags" lsp-go-build-flags)

clients/lsp-groovy.el

@@ -48,7 +48,7 @@
   :risky t
   :type 'lsp-string-vector)
 
-(lsp-register-custom-settings
+(lsp-register-new-settings
  '(("groovy.classpath" lsp-groovy-classpath)))
 
 (lsp-register-client

clients/lsp-haxe.el

@@ -170,7 +170,7 @@
   :type 'string
   :group 'lsp-haxe)
 
-(lsp-register-custom-settings
+(lsp-register-new-settings
  '(("haxe.hxml" lsp-haxe-hxml)
    ("haxe.postfixCompletion" lsp-haxe-postfix-completion)
    ("haxe.exclude" lsp-haxe-exclude)

clients/lsp-html.el

@@ -159,7 +159,7 @@ styles."
   :group 'lsp-html
   :package-version '(lsp-mode . "6.1"))
 
-(lsp-register-custom-settings
+(lsp-register-new-settings
  '(("html.trace.server" lsp-html-trace-server)
    ("html.autoClosingTags" lsp-html-auto-closing-tags t)
    ("html.validate.styles" lsp-html-validate-styles t)

clients/lsp-idris.el

@@ -48,7 +48,7 @@
   :type '(choice (:tag "off" "messages" "verbose"))
   :package-version '(lsp-mode . "9.0.0"))
 
-(lsp-register-custom-settings
+(lsp-register-new-settings
   '(("idris2-lsp.trace.server" lsp-idris2-lsp-trace-server)
     ("idris2-lsp.path" lsp-idris2-lsp-path)))