lsp: Add support for create workspaceEdit resource operation

3 files changed, 70 insertions, 2 deletions

diff --git a/runtime/lua/vim/lsp/protocol.lua b/runtime/lua/vim/lsp/protocol.lua
index 187aad7684..085ca7b4a1 100644
--- a/runtime/lua/vim/lsp/protocol.lua
+++ b/runtime/lua/vim/lsp/protocol.lua
@@ -750,7 +750,7 @@ function protocol.make_client_capabilities()
       workspaceFolders = true;
       applyEdit = true;
       workspaceEdit = {
-        resourceOperations = {'rename',},
+        resourceOperations = {'rename', 'create',},
       };
     };
     callHierarchy = {
diff --git a/runtime/lua/vim/lsp/util.lua b/runtime/lua/vim/lsp/util.lua
index 601a6ae8ca..82fd77ea90 100644
--- a/runtime/lua/vim/lsp/util.lua
+++ b/runtime/lua/vim/lsp/util.lua
@@ -635,6 +635,18 @@ function M.rename(old_fname, new_fname, opts)
 end
 
 
+local function create_file(change)
+  local opts = change.options or {}
+  -- from spec: Overwrite wins over `ignoreIfExists`
+  local fname = vim.uri_to_fname(change.uri)
+  if not opts.ignoreIfExists or opts.overwrite then
+    local file = io.open(fname, 'w')
+    file:close()
+  end
+  vim.fn.bufadd(fname)
+end
+
+
 --- Applies a `WorkspaceEdit`.
 ---
 --@param workspace_edit (table) `WorkspaceEdit`
@@ -648,8 +660,10 @@ function M.apply_workspace_edit(workspace_edit)
           vim.uri_to_fname(change.newUri),
           change.options
         )
+      elseif change.kind == 'create' then
+        create_file(change)
       elseif change.kind then
-        -- TODO(ashkan) handle CreateFile/DeleteFile
+        -- TODO(ashkan) handle DeleteFile
         error(string.format("Unsupported change: %q", vim.inspect(change)))
       else
         M.apply_text_document_edit(change, idx)
diff --git a/test/functional/plugin/lsp_spec.lua b/test/functional/plugin/lsp_spec.lua
index 2fd9934e7d..eb8f5e8824 100644
--- a/test/functional/plugin/lsp_spec.lua
+++ b/test/functional/plugin/lsp_spec.lua
@@ -1265,6 +1265,60 @@ describe('LSP', function()
         return vim.api.nvim_buf_get_lines(target_bufnr, 0, -1, false)
       ]], make_workspace_edit(edits), target_bufnr))
     end)
+    it('Supports file creation with CreateFile payload', function()
+      local tmpfile = helpers.tmpname()
+      os.remove(tmpfile) -- Should not exist, only interested in a tmpname
+      local uri = exec_lua('return vim.uri_from_fname(...)', tmpfile)
+      local edit = {
+        documentChanges = {
+          {
+            kind = 'create',
+            uri = uri,
+          },
+        }
+      }
+      exec_lua('vim.lsp.util.apply_workspace_edit(...)', edit)
+      eq(true, exec_lua('return vim.loop.fs_stat(...) ~= nil', tmpfile))
+    end)
+    it('createFile does not touch file if it exists and ignoreIfExists is set', function()
+      local tmpfile = helpers.tmpname()
+      write_file(tmpfile, 'Dummy content')
+      local uri = exec_lua('return vim.uri_from_fname(...)', tmpfile)
+      local edit = {
+        documentChanges = {
+          {
+            kind = 'create',
+            uri = uri,
+            options = {
+              ignoreIfExists = true,
+            },
+          },
+        }
+      }
+      exec_lua('vim.lsp.util.apply_workspace_edit(...)', edit)
+      eq(true, exec_lua('return vim.loop.fs_stat(...) ~= nil', tmpfile))
+      eq('Dummy content', read_file(tmpfile))
+    end)
+    it('createFile overrides file if overwrite is set', function()
+      local tmpfile = helpers.tmpname()
+      write_file(tmpfile, 'Dummy content')
+      local uri = exec_lua('return vim.uri_from_fname(...)', tmpfile)
+      local edit = {
+        documentChanges = {
+          {
+            kind = 'create',
+            uri = uri,
+            options = {
+              overwrite = true,
+              ignoreIfExists = true, -- overwrite must win over ignoreIfExists
+            },
+          },
+        }
+      }
+      exec_lua('vim.lsp.util.apply_workspace_edit(...)', edit)
+      eq(true, exec_lua('return vim.loop.fs_stat(...) ~= nil', tmpfile))
+      eq('', read_file(tmpfile))
+    end)
   end)
 
   describe('completion_list_to_complete_items', function()