nvim-cmp: fix snippet not being able to be null

plugins/completion/nvim-cmp/default.nix

@@ -7,9 +7,11 @@ let
   cmpLib = import ./cmp-helpers.nix args;
   # functionName should be a string
   # parameters should be a list of strings
-  wrapWithFunction = functionName: parameters: let
+  wrapWithFunction = functionName: parameters:
+    let
       parameterString = strings.concatStringsSep "," parameters;
-  in ''${functionName}(${parameterString})'';
+    in
+    ''${functionName}(${parameterString})'';
 in
 {
   options.programs.nixvim.plugins.nvim-cmp = {
@@ -68,6 +70,7 @@ in
         [ "insert" "cmdline" ]
       '';
     };
+
     mapping = mkOption {
       default = null;
       type = types.nullOr (types.attrsOf (types.either types.str (types.submodule ({ ... }: {
@@ -212,7 +215,8 @@ in
       '';
     };
 
-    sources = let
+    sources =
+      let
         source_config = types.submodule ({ ... }: {
           options = {
             name = mkOption {
@@ -258,7 +262,8 @@ in
             };
           };
         });
-    in mkOption {
+      in
+      mkOption {
         default = null;
         type = with types; nullOr (either (listOf source_config) (listOf (listOf source_config)));
         description = ''
@@ -288,12 +293,14 @@ in
       }));
     };
 
-    window = let
+    window =
+      let
         # Reusable options
         border = with types; mkNullOrOption (either str (listOf str)) null;
         winhighlight = mkNullOrOption types.str null;
         zindex = mkNullOrOption types.int null;
-    in mkOption {
+      in
+      mkOption {
         default = null;
         type = types.nullOr (types.submodule ({ ... }: {
           options = {
@@ -324,7 +331,8 @@ in
     experimental = mkNullOrOption types.attrs "Experimental features";
   };
 
-  config = let
+  config =
+    let
       options = {
         enabled = cfg.enable;
         performance = cfg.performance;
@@ -334,42 +342,56 @@ in
         # If null then null
         # If an attribute is a string, just treat it as lua code for that mapping
         # If an attribute is a module, create a mapping with cmp.mapping() using the action as the first input and the modes as the second.
-      mapping = let
+        mapping =
-        mappings = if (isNull cfg.mapping) then null
+          let
-          else mapAttrs (bind: mapping: helpers.mkRaw (if isString mapping then mapping
+            mappings =
-            else "cmp.mapping(${mapping.action}${optionalString (mapping.modes != null && length mapping.modes >= 1) ("," + (helpers.toLuaObject mapping.modes))})")) cfg.mapping;
+              if (isNull cfg.mapping) then null
+              else
+                mapAttrs
+                  (bind: mapping: helpers.mkRaw (if isString mapping then mapping
+                  else "cmp.mapping(${mapping.action}${optionalString (mapping.modes != null && length mapping.modes >= 1) ("," + (helpers.toLuaObject mapping.modes))})"))
+                  cfg.mapping;
             luaMappings = (helpers.toLuaObject mappings);
             wrapped = lists.fold (presetName: prevString: ''cmp.mapping.preset.${presetName}(${prevString})'') luaMappings cfg.mappingPresets;
-      in  helpers.mkRaw wrapped;
+          in
+          helpers.mkRaw wrapped;
+
         snippet = {
-        expand = if (isNull cfg.snippet.expand) then null else helpers.mkRaw cfg.snippet.expand;
+          expand = if (isNull cfg.snippet || isNull cfg.snippet.expand) then null else helpers.mkRaw cfg.snippet.expand;
         };
+
         completion = if (isNull cfg.completion) then null else {
           keyword_length = cfg.completion.keyword_length;
           keyword_pattern = cfg.completion.keyword_pattern;
           autocomplete = if (isNull cfg.completion.autocomplete) then null else mkRaw cfg.completion.autocomplete;
           completeopt = cfg.completion.completeopt;
         };
+
         confirmation = if (isNull cfg.confirmation) then null else {
           get_commit_characters =
             if (isString cfg.confirmation.get_commit_characters) then helpers.mkRaw cfg.confirmation.get_commit_characters
             else cfg.confirmation.get_commit_characters;
         };
+
         formatting = if (isNull cfg.formatting) then null else {
           fields = cfg.formatting.fields;
           format = if (isNull cfg.formatting.format) then null else helpers.mkRaw cfg.formatting.format;
         };
+
         matching = cfg.matching;
+
         sorting = if (isNull cfg.sorting) then null else {
           priority_weight = cfg.sorting.priority_weight;
           comparators = if (isNull cfg.sorting.comparators) then null else helpers.mkRaw cfg.sorting.comparators;
         };
+
         sources = cfg.sources;
         view = cfg.view;
         window = cfg.window;
         experimental = cfg.experimental;
       };
-  in mkIf cfg.enable {
+    in
+    mkIf cfg.enable {
       programs.nixvim = {
         extraPlugins = [ pkgs.vimPlugins.nvim-cmp ];
 
@@ -380,18 +402,22 @@ in
 
         # If auto_enable_sources is set to true, figure out which are provided by the user
         # and enable the corresponding plugins.
-      plugins = let
+        plugins =
+          let
             flattened_sources = if (isNull cfg.sources) then [ ] else flatten cfg.sources;
             # Take only the names from the sources provided by the user
             found_sources = lists.unique (lists.map (source: source.name) flattened_sources);
             # A list of known source names
             known_source_names = attrNames cmpLib.pluginAndSourceNames;
 
-        attrs_enabled = listToAttrs (map (name: {
+            attrs_enabled = listToAttrs (map
+              (name: {
                 name = cmpLib.pluginAndSourceNames.${name};
                 value.enable = mkIf (elem name found_sources) true;
-        }) known_source_names);
+              })
-      in mkIf cfg.auto_enable_sources attrs_enabled;
+              known_source_names);
+          in
+          mkIf cfg.auto_enable_sources attrs_enabled;
       };
     };
 }