1 files changed, 31 insertions, 4 deletions
diff --git a/lua/nvim-lsp-installer/core/async/spawn.lua b/lua/nvim-lsp-installer/core/async/spawn.lua
index e643f098..5fc7eee7 100644
--- a/lua/nvim-lsp-installer/core/async/spawn.lua
+++ b/lua/nvim-lsp-installer/core/async/spawn.lua
@@ -1,34 +1,61 @@
 local a = require "nvim-lsp-installer.core.async"
+local Result = require "nvim-lsp-installer.core.result"
 local process = require "nvim-lsp-installer.process"
 local platform = require "nvim-lsp-installer.platform"
 
 local async_spawn = a.promisify(process.spawn)
 
+---@type Record<string, fun(opts: JobSpawnOpts): Result>
 local spawn = {
     aliases = {
         npm = platform.is_win and "npm.cmd" or "npm",
     },
 }
 
+local function Failure(err, cmd)
+    return Result.failure(setmetatable(err, {
+        __tostring = function()
+            return ("spawn: %s failed with exit code %d"):format(cmd, err.exit_code)
+        end,
+    }))
+end
+
 setmetatable(spawn, {
     __index = function(self, k)
         return function(args)
-            local stdio = process.in_memory_sink()
             local cmd_args = {}
             for i, arg in ipairs(args) do
                 cmd_args[i] = arg
             end
             ---@type JobSpawnOpts
             local spawn_args = {
-                stdio_sink = stdio.sink,
+                stdio_sink = args.stdio_sink,
                 cwd = args.cwd,
                 env = args.env,
                 args = cmd_args,
             }
+
+            local stdio
+            if not spawn_args.stdio_sink then
+                stdio = process.in_memory_sink()
+                spawn_args.stdio_sink = stdio.sink
+            end
+
             local cmd = self.aliases[k] or k
             local _, exit_code = async_spawn(cmd, spawn_args)
-            assert(exit_code == 0, ("%q exited with an error code: %d."):format(cmd, exit_code))
-            return table.concat(stdio.buffers.stdout, ""), table.concat(stdio.buffers.stderr, "")
+
+            if exit_code == 0 then
+                return Result.success {
+                    stdout = stdio and table.concat(stdio.buffers.stdout, "") or nil,
+                    stderr = stdio and table.concat(stdio.buffers.stderr, "") or nil,
+                }
+            else
+                return Failure({
+                    exit_code = exit_code,
+                    stdout = stdio and table.concat(stdio.buffers.stdout, "") or nil,
+                    stderr = stdio and table.concat(stdio.buffers.stderr, "") or nil,
+                }, cmd)
+            end
         end
     end,
 })