add async managers (#536)

1 files changed, 79 insertions, 0 deletions

diff --git a/lua/nvim-lsp-installer/core/spawn.lua b/lua/nvim-lsp-installer/core/spawn.lua
new file mode 100644
index 00000000..992b1557
--- /dev/null
+++ b/lua/nvim-lsp-installer/core/spawn.lua
@@ -0,0 +1,79 @@
+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)
+
+---@alias JobSpawn Record<string, async fun(opts: JobSpawnOpts): Result>
+---@type JobSpawn
+local spawn = {
+    _aliases = {
+        npm = platform.is_win and "npm.cmd" or "npm",
+        gem = platform.is_win and "gem.cmd" or "gem",
+        composer = platform.is_win and "composer.bat" or "composer",
+    },
+    -- Utility function for optionally including arguments.
+    ---@generic T
+    ---@param condition boolean
+    ---@param value T
+    ---@return T
+    _when = function(condition, value)
+        return condition and value or vim.NIL
+    end,
+}
+
+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)
+        ---@param args string|nil|string[][]
+        return function(args)
+            local cmd_args = {}
+            for _, arg in ipairs(args) do
+                if type(arg) == "table" then
+                    vim.list_extend(cmd_args, arg)
+                elseif arg ~= vim.NIL then
+                    cmd_args[#cmd_args + 1] = arg
+                end
+            end
+            ---@type JobSpawnOpts
+            local spawn_args = {
+                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)
+
+            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,
+})
+
+return spawn