plugins/cmp: refactor source->plugin association

Introduce the internal option `cmpSourcePlugins` where plugins can
register their nvim-cmp source name association.

plugins/completion/cmp/auto-enable.nix

@@ -0,0 +1,90 @@
+{
+  lib,
+  helpers,
+  config,
+  ...
+}:
+with lib;
+let
+  cfg = config.plugins.cmp;
+
+  extractSources = { sources, ... }: if isList sources then sources else [ ];
+
+  # Collect the names of the sources provided by the user
+  # ["foo" "bar"]
+  enabledSources =
+    pipe
+      [
+        # cfg.setup.sources
+        (extractSources cfg.settings)
+        # cfg.filetype.<name>.sources
+        (mapAttrsToList (_: extractSources) cfg.filetype)
+        # cfg.cmdline.<name>.sources
+        (mapAttrsToList (_: extractSources) cfg.cmdline)
+      ]
+      [
+        flatten
+        (map (getAttr "name"))
+        unique
+      ];
+in
+{
+  options = {
+    # Note: this option must be outside of `plugins` to avoid infinite recursion
+    cmpSourcePlugins = mkOption {
+      type = with types; attrsOf str;
+      default = { };
+      description = ''
+        Internal option used to associate nvim-cmp source names with nixvim plugin module names.
+
+        Maps `<source-name> = <plugin-name>` where _plugin-name_ is the module name: `plugins.<plugin-name>.enable`.
+      '';
+      example = {
+        foo = "cmp-foo";
+        bar = "cmp-bar";
+      };
+      internal = true;
+      visible = false;
+    };
+
+    plugins.cmp.autoEnableSources = mkOption {
+      type = types.bool;
+      default = true;
+      example = false;
+      description = ''
+        Scans the sources array and enable the corresponding plugins if they are known to nixvim.
+      '';
+    };
+  };
+
+  config = mkIf (cfg.enable && cfg.autoEnableSources) (mkMerge [
+    {
+      warnings =
+        # TODO: expand this warning to ft & cmd sources lists and `showDefs` the offending definitions
+        optional (helpers.nixvimTypes.isRawType cfg.settings.sources) ''
+          Nixvim (plugins.cmp): You have enabled `autoEnableSources` that tells Nixvim to automatically
+          enable the source plugins with respect to the list of sources provided in `settings.sources`.
+          However, the latter is proveded as a raw lua string which is not parseable by Nixvim.
+
+          If you want to keep using raw lua for defining your sources:
+          - Ensure you enable the relevant plugins manually in your configuration;
+          - Dismiss this warning by explicitly setting `autoEnableSources` to `false`;
+        '';
+
+      # If the user has enabled the `foo` and `bar` sources, then `plugins` will look like:
+      # {
+      #   cmp-foo.enable = true;
+      #   cmp-bar.enable = true;
+      # }
+      plugins = mapAttrs' (source: name: {
+        inherit name;
+        value.enable = mkIf (elem source enabledSources) true;
+      }) config.cmpSourcePlugins;
+    }
+    {
+      plugins.lsp.capabilities = mkIf (elem "nvim_lsp" enabledSources) ''
+        capabilities = vim.tbl_deep_extend("force", capabilities, require('cmp_nvim_lsp').default_capabilities())
+      '';
+    }
+  ]);
+}

plugins/completion/cmp/cmp-helpers.nix

@@ -7,10 +7,11 @@
 }:
 with helpers.vim-plugin;
 with lib;
-rec {
+{
   mkCmpSourcePlugin =
     {
       name,
+      sourceName,
       extraPlugins ? [ ],
       useDefaultPackage ? true,
       ...
@@ -20,49 +21,8 @@ rec {
       extraPlugins = extraPlugins ++ (lists.optional useDefaultPackage pkgs.vimPlugins.${name});
 
       maintainers = [ maintainers.GaetanLepage ];
+
+      # Register the source -> plugin name association
+      imports = [ { cmpSourcePlugins.${sourceName} = name; } ];
     };
-
-  extractSourcesFromOptionValue = sources: if isList sources then sources else [ ];
-
-  autoInstallSourcePluginsModule =
-    cfg:
-    let
-      # cfg.setup.sources
-      setupSources = extractSourcesFromOptionValue cfg.settings.sources;
-      # cfg.filetype.<name>.sources
-      filetypeSources = mapAttrsToList (
-        _: filetypeConfig: extractSourcesFromOptionValue filetypeConfig.sources
-      ) cfg.filetype;
-      # cfg.cmdline.<name>.sources
-      cmdlineSources = mapAttrsToList (
-        _: cmdlineConfig: extractSourcesFromOptionValue cmdlineConfig.sources
-      ) cfg.cmdline;
-
-      # [{name = "foo";} {name = "bar"; x = 42;} ...]
-      allSources = flatten (setupSources ++ filetypeSources ++ cmdlineSources);
-
-      # Take only the names from the sources provided by the user
-      # ["foo" "bar"]
-      foundSources = lists.unique (map (source: source.name) allSources);
-
-      # If the user has enabled the `foo` and `bar` sources, this attrs will look like:
-      # {
-      #   cmp-foo.enable = true;
-      #   cmp-bar.enable = true;
-      # }
-      attrsEnabled = mapAttrs' (sourceName: pluginName: {
-        name = pluginName;
-        value.enable = mkIf (elem sourceName foundSources) true;
-      }) (import ./sources.nix);
-
-      lspCapabilities = mkIf (elem "nvim_lsp" foundSources) {
-        lsp.capabilities = ''
-          capabilities = vim.tbl_deep_extend("force", capabilities, require('cmp_nvim_lsp').default_capabilities())
-        '';
-      };
-    in
-    mkMerge [
-      (mkIf cfg.autoEnableSources attrsEnabled)
-      lspCapabilities
-    ];
 }

plugins/completion/cmp/default.nix

@@ -16,42 +16,22 @@ helpers.neovim-plugin.mkNeovimPlugin config {
 
   maintainers = [ maintainers.GaetanLepage ];
 
+  imports = [
     # Introduced on 2024 February 21
     # TODO: remove ~June 2024
-  imports = [
     ./deprecations.nix
+    ./auto-enable.nix
     ./sources
   ];
   deprecateExtraOptions = true;
 
+  inherit (cmpOptions) settingsOptions settingsExample;
   extraOptions = {
-    autoEnableSources = mkOption {
-      type = types.bool;
-      default = true;
-      description = ''
-        Scans the sources array and installs the plugins if they are known to nixvim.
-      '';
-    };
-
     inherit (cmpOptions) filetype cmdline;
   };
 
-  inherit (cmpOptions) settingsOptions settingsExample;
-
   callSetup = false;
   extraConfig = cfg: {
-    warnings =
-      optional (cfg.autoEnableSources && (helpers.nixvimTypes.isRawType cfg.settings.sources))
-        ''
-          Nixvim (plugins.cmp): You have enabled `autoEnableSources` that tells Nixvim to automatically
-          enable the source plugins with respect to the list of sources provided in `settings.sources`.
-          However, the latter is proveded as a raw lua string which is not parseable by Nixvim.
-
-          If you want to keep using raw lua for defining your sources:
-          - Ensure you enable the relevant plugins manually in your configuration;
-          - Dismiss this warning by explicitly setting `autoEnableSources` to `false`;
-        '';
-
     extraConfigLua =
       ''
         local cmp = require('cmp')
@@ -68,9 +48,5 @@ helpers.neovim-plugin.mkNeovimPlugin config {
           cmdtype: settings: "cmp.setup.cmdline('${cmdtype}', ${helpers.toLuaObject settings})\n"
         ) cfg.cmdline
       ));
-
-    # If autoEnableSources is set to true, figure out which are provided by the user
-    # and enable the corresponding plugins.
-    plugins = (import ./cmp-helpers.nix args).autoInstallSourcePluginsModule cfg;
   };
 }

plugins/completion/cmp/sources/default.nix

@@ -15,8 +15,11 @@ let
       pkgs
       ;
   };
-  cmpSourcesPluginNames = attrValues (import ../sources.nix);
-  pluginModules = map (name: cmpLib.mkCmpSourcePlugin { inherit name; }) cmpSourcesPluginNames;
+
+  cmpSourcesPluginNames = import ../sources.nix;
+  pluginModules = mapAttrsToList (
+    sourceName: name: cmpLib.mkCmpSourcePlugin { inherit sourceName name; }
+  ) cmpSourcesPluginNames;
 in
 {
   # For extra cmp plugins

tests/fetch-tests.nix

@@ -57,7 +57,6 @@ let
             inherit pkgs lib helpers;
             config = { };
           };
-          cmp-sources = import ../plugins/completion/cmp/sources.nix;
         };
         inherit namespace;
       }

tests/test-sources/plugins/completion/cmp-all-sources.nix

@@ -1,6 +1,9 @@
-{ pkgs, cmp-sources, ... }:
+{ pkgs, ... }:
 {
   all-sources = {
+    module =
+      { config, ... }:
+      {
         plugins = {
           copilot-lua = {
             enable = true;
@@ -18,12 +21,18 @@
                   # We do not provide the required HF_API_KEY environment variable.
                   "cmp_ai"
                 ] ++ optional (pkgs.stdenv.hostPlatform.system == "aarch64-linux") "cmp_tabnine";
-
-            filterFunc = sourceName: !(elem sourceName disabledSources);
-
-            sourceNames = filter filterFunc (attrNames cmp-sources);
               in
-          map (sourceName: { name = sourceName; }) sourceNames;
+              pipe config.cmpSourcePlugins [
+                # All known source names
+                attrNames
+                # Filter out disabled sources
+                (filter (name: !(elem name disabledSources)))
+                # Convert names to source attributes
+                (map (name: {
+                  inherit name;
+                }))
+              ];
+          };
         };
       };
   };