feat: neovim envs as fallback

README.md

@@ -37,6 +37,12 @@ local default_config = {
   ---Automatically adds a dap on_config listener.
   ---@type boolean?
   add_dap_listener = true,
+  ---Also sets environment variables using the Neovim API. Only works if
+  ---`add_dap_listener` is enabled. This is enabled by default since it adds no
+  ---overhead and can be helpful for certain DAP servers that don’t support the
+  ---`env` option.
+  ---@type boolean?
+  use_neovim_env = true,
   ---Print additional debug messages. Useful to check what your inputs are
   ---evaluating to.
   ---@type boolean?
@@ -51,7 +57,9 @@ manually.
 
 ### Using `envFile`
 
-Your project-local `.nvim.lua` or any other per-project configuration file.
+Below is an example for Go, using your project-local `.nvim.lua` or any other
+per-project configuration file. If you’re unfamiliar with such setups, see
+`:help exrc`.
 
 ```lua
 local dap = require("dap")
@@ -63,7 +71,9 @@ table.insert(dap.configurations.go, {
   timeout = 10000,
   outputMode = "remote",
   program = "main.go",
-  envFile = "${workspaceFolder}/.env", -- will be read, parsed, and passed as "env" table.
+
+  -- will be read, parsed, and passed as "env" table.
+  envFile = "${workspaceFolder}/.env",
 })
 ```
 
@@ -91,20 +101,20 @@ custom one), you can still use our helper functions
 local envfile = require("nvim-dap-envfile")
 ```
 
-### `envfile.eval_vars(str: string) -> string`
+### `envfile.expand_path_vars(str: string) -> string`
 
 Expands VS Code–style variables inside a string. For available variables see
 below.
 
 ```lua
-local resolved = envfile.eval_vars("${workspaceFolder}/.env")
+local resolved = envfile.expand_path_vars("${workspaceFolder}/.env")
 -- e.g. "/home/user/project/.env"
 ```
 
 ### `envfile.load_env_file(path: string) -> table`
 
 Parses a `.env` file and returns a Lua table of key/value pairs. Path is
-evaluated using `eval_vars`.
+evaluated using `expand_path_vars`.
 
 ```lua
 local env = envfile.load_env_file("${workspaceFolder}/.env")
@@ -114,6 +124,22 @@ vim.print(env)
 
 Quotes around values (`"foo"` or `'foo'`) are stripped automatically.
 
+### `envfile.set_neovim_env(envs: table<string, string>) -> nil`
+
+Sets environment variables for the current Neovim session using the Neovim API
+(`vim.env`). Each key/value pair in `envs` is added to `vim.env`, making the
+variables available to shell commands, plugins, and other Lua code executed
+within Neovim.
+
+```lua
+envfile.set_neovim_env({
+  DB_HOST = "localhost",
+  PORT = "8080",
+})
+-- vim.env.DB_HOST == "localhost"
+-- vim.env.PORT == "8080"
+```
+
 ### Variable Expansion
 
 | Variable                     | Example Result               |

lua/nvim-dap-envfile.lua

@@ -44,6 +44,12 @@ local default_config = {
   ---Automatically adds a dap on_config listener.
   ---@type boolean?
   add_dap_listener = true,
+  ---Also sets environment variables using the Neovim API. Only works if
+  ---`add_dap_listener` is enabled. This is enabled by default since it adds no
+  ---overhead and can be helpful for certain DAP servers that don’t support the
+  ---`env` option.
+  ---@type boolean?
+  use_neovim_env = true,
   ---Print additional debug messages. Useful to check what your inputs are
   ---evaluating to.
   ---@type boolean?
@@ -54,9 +60,11 @@ local M = {
   config = default_config,
 }
 
+---@alias env_table table<string, string>
+
 ---@param str string
 ---@return string str String with evaluated variables (if any)
-function M.eval_vars(str)
+function M.expand_path_vars(str)
   for pattern, replace_fn in pairs(replacements) do
     str = str:gsub(pattern, replace_fn)
   end
@@ -66,15 +74,16 @@ end
 
 ---@param path string Path for .env file. Variables like ${file} are
 --- automatically evaluated.
----@return table env Table with env values, read from path.
+---@return env_table env A key-value table of envs.
 function M.load_env_file(path)
-  local env = {}
+  local env = {} ---@type table<string,string>
   local file = io.open(path, "r")
   if not file then
     return env
   end
 
   for line in file:lines() do
+    ---@type string, string
     local key, value = line:match("^%s*([%w_]+)%s*=%s*(.+)%s*$")
     if key and value then
       -- remove quotes
@@ -86,6 +95,16 @@ function M.load_env_file(path)
   return env
 end
 
+---@param envs env_table
+function M.set_neovim_env(envs)
+  for k, v in pairs(envs) do
+    vim.env[k] = v
+    if M.config.debug or false then
+      vim.print("vim.env: set " .. k .. " to " .. v)
+    end
+  end
+end
+
 ---@param opts Config
 function M.setup(opts)
   local ok, dap = pcall(require, "dap")
@@ -101,18 +120,21 @@ function M.setup(opts)
       local config = vim.deepcopy(original_config)
 
       if config.envFile then
-        local path = M.eval_vars(config.envFile)
+        local path = M.expand_path_vars(config.envFile)
         if M.config.debug then
           vim.print("env path: " .. path)
         end
 
         if vim.fn.filereadable(path) == 1 then
           local env_vars = M.load_env_file(path)
           if M.config.debug then
-            vim.print("envs: " .. env_vars)
+            vim.print("envs: " .. vim.inspect(env_vars))
           end
 
           config.env = vim.tbl_extend("force", config.env or {}, env_vars)
+          if M.config.use_neovim_env then
+            M.set_neovim_env(env_vars)
+          end
         else
           vim.notify("No .env file found: " .. path, vim.log.levels.WARN, notify_opts)
         end

tests/nvim-dap-envfile/eval_vars_spec.lua

@@ -27,39 +27,40 @@ describe("eval_vars()", function()
         return "/home/user/project"
       end,
     }
+    ---@diagnostic disable-next-line: duplicate-set-field
     os.getenv = function(_)
       return "test"
     end
   end)
 
   it("replaces ${fileBasename}", function()
-    local result = M.eval_vars("File: ${fileBasename}")
+    local result = M.expand_path_vars("File: ${fileBasename}")
     assert.are.equal("File: file.lua", result)
   end)
 
   it("replaces ${fileBasenameNoExtension}", function()
-    local result = M.eval_vars("Name: ${fileBasenameNoExtension}")
+    local result = M.expand_path_vars("Name: ${fileBasenameNoExtension}")
     assert.are.equal("Name: file", result)
   end)
 
   it("replaces ${workspaceFolderBasename}", function()
-    local result = M.eval_vars("Project: ${workspaceFolderBasename}")
+    local result = M.expand_path_vars("Project: ${workspaceFolderBasename}")
     assert.are.equal("Project: project", result)
   end)
 
   it("replaces ${env:TEST_ENV}", function()
-    local result = M.eval_vars("${env:TEST_ENV}")
+    local result = M.expand_path_vars("${env:TEST_ENV}")
     assert.are.equal("test", result)
   end)
 
   it("handles multiple replacements", function()
     local input = "Dir: ${workspaceFolder}, File: ${fileBasename}"
     local expected = "Dir: /home/user/project, File: file.lua"
-    assert.are.equal(expected, M.eval_vars(input))
+    assert.are.equal(expected, M.expand_path_vars(input))
   end)
 
   it("returns same string if no variables", function()
     local input = "no variables here"
-    assert.are.equal(input, M.eval_vars(input))
+    assert.are.equal(input, M.expand_path_vars(input))
   end)
 end)

tests/nvim-dap-envfile/set_neovim_env_spec.lua

@@ -0,0 +1,52 @@
+local M = require("nvim-dap-envfile")
+
+describe("set_neovim_env", function()
+  local original_env = {}
+
+  before_each(function()
+    -- Backup and clear test vars
+    original_env.TEST_VAR1 = vim.env.TEST_VAR1
+    original_env.TEST_VAR2 = vim.env.TEST_VAR2
+    vim.env.TEST_VAR1 = nil
+    vim.env.TEST_VAR2 = nil
+  end)
+
+  after_each(function()
+    -- Restore environment
+    vim.env.TEST_VAR1 = original_env.TEST_VAR1
+    vim.env.TEST_VAR2 = original_env.TEST_VAR2
+  end)
+
+  it("sets environment variables in vim.env", function()
+    local envs = {
+      TEST_VAR1 = "hello",
+      TEST_VAR2 = "world",
+    }
+
+    M.set_neovim_env(envs)
+
+    assert.equal("hello", vim.env.TEST_VAR1)
+    assert.equal("world", vim.env.TEST_VAR2)
+  end)
+
+  it("works with os.getenv", function()
+    local envs = {
+      TEST_VAR1 = "hello",
+      TEST_VAR2 = "world",
+    }
+
+    M.set_neovim_env(envs)
+
+    assert.equal("hello", os.getenv("TEST_VAR1"))
+    assert.equal("world", os.getenv("TEST_VAR2"))
+  end)
+
+  it("overwrites existing environment variables", function()
+    vim.env.TEST_VAR1 = "old"
+    local envs = { TEST_VAR1 = "new" }
+
+    M.set_neovim_env(envs)
+
+    assert.equal("new", vim.env.TEST_VAR1)
+  end)
+end)