feat(dap): add support for nvim-dap with haskell-debug-adapter (#180)

<!-- markdownlint-disable -->
###### Description of changes

###### Things done

- [x] Tested, as applicable:
  - [x] Manually
  - [x] Added plenary specs
- [x] Updated
[CHANGELOG.md](https://github.com/MrcJkb/haskell-tools.nvim/blob/master/CHANGELOG.md)
(if applicable).
- [x] Fits
[CONTRIBUTING.md](https://github.com/MrcJkb/haskell-tools.nvim/blob/master/CONTRIBUTING.md)

Author: mrcjkb

CHANGELOG.md

@@ -5,6 +5,12 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [1.10.0] - 2023-04-17
+### Added
+- Support for [`nvim-dap`](https://github.com/mfussenegger/nvim-dap)
+  with [`haskell-debug-adapter`](https://hackage.haskell.org/package/haskell-debug-adapter),
+  an experimental debug adapter for Haskell.
+
 ## [1.9.7] - 2023-04-15
 ### Fixed
 - Remove some prints.

README.md

@@ -44,6 +44,8 @@
   installation (recommended for better hoogle search performance)
 - [`fast-tags`](https://github.com/elaforge/fast-tags)
   (for automatic tag generation as a fallback for [`vim.lsp.tagfunc`](https://neovim.io/doc/user/lsp.html#vim.lsp.tagfunc())).
+- [`haskell-debug-adapter`](https://github.com/phoityne/haskell-debug-adapter/) and
+  [`nvim-dap`](https://github.com/mfussenegger/nvim-dap).
 
 ## Installation
 
@@ -97,7 +99,6 @@ To get started quickly with the default setup, add the following to `~/.config/n
 
 ```lua
 local ht = require('haskell-tools')
-local buffer = vim.api.nvim_get_current_buf()
 local def_opts = { noremap = true, silent = true, }
 ht.start_or_attach {
   hls = {
@@ -124,6 +125,10 @@ vim.keymap.set('n', '<leader>rf', function()
   ht.repl.toggle(vim.api.nvim_buf_get_name(0))
 end, def_opts)
 vim.keymap.set('n', '<leader>rq', ht.repl.quit, opts)
+
+-- Detect nvim-dap launch configurations
+-- (requires nvim-dap and haskell-debug-adapter)
+ht.dap.discover_configurations(bufnr)
 ```
 
 >**Note**
@@ -137,37 +142,31 @@ to generate a database.
 
 ## Features
 
-- [x] Basic haskell-language-server functionality on par with `nvim-lspconfig.hls`
-
-### Beyond `nvim-lspconfig.hls`
-
-- [x] Dynamically load `haskell-language-server` settings per project from JSON files.
-- [x] Clean shutdown of language server on exit to prevent corrupted files
+- [x] **Set up a `haskell-language-server` client.**
+- [x] **Dynamically load `haskell-language-server` settings per project
+  from JSON files.**
+- [x] **Clean shutdown of language server on exit to prevent corrupted files**
       ([see ghc #14533](https://gitlab.haskell.org/ghc/ghc/-/issues/14533)).
-- [x] Automatically adds capabilities for the following plugins, if loaded:
+- [x] **Automatically adds capabilities for the following plugins, if loaded:**
   - [cmp-nvim-lsp](https://github.com/hrsh7th/cmp-nvim-lsp)
     (provides completion sources for [nvim-cmp](https://github.com/hrsh7th/nvim-cmp)).
   - [nvim-lsp-selection-range](https://github.com/camilledejoye/nvim-lsp-selection-range)
     (Adds haskell-specific [expand selection](https://haskell-language-server.readthedocs.io/en/latest/features.html#selection-range)
     support).
-- [x] Automatically refreshes code lenses by default,
-      which haskell-language-server heavily relies on. [Can be disabled.](#advanced-configuration)
+- [x] **Automatically refreshes code lenses by default,**
+      which `haskell-language-server` heavily relies on. [Can be disabled.](#advanced-configuration)
 
 ![codeLens](https://user-images.githubusercontent.com/12857160/219738949-c20ed266-3b2d-441e-82fe-faf50f5c582a.gif)
 
-### Beyond haskell-language-server
-
-The below features are not implemented by haskell-language-server.
-
-#### Evaluate all code snippets at once
+- [x] **Evaluate all code snippets at once**
 
 `haskell-language-server` can evaluate code snippets using code lenses.
 `haskell-tools.nvim` provides a `require('haskell-tools').lsp.buf_eval_all()`
 shortcut to evaluate all of them at once.
 
 ![evalAll](https://user-images.githubusercontent.com/12857160/219743339-e7b7f4e0-478b-4310-a903-36d0a5564937.gif)
 
-#### Hoogle-search for signature
+- [x] **Hoogle-search for signature**
 
 - Search for the type signature under the cursor.
 - Falls back to the word under the cursor if the type signature cannot be determined.
@@ -182,14 +181,14 @@ require('haskell-tools').hoogle.hoogle_signature()
 
 ![hoogleSig](https://user-images.githubusercontent.com/12857160/219745914-505a8fc8-9cb9-49fe-b763-a0dea2a3420b.gif)
 
-#### Hole-driven development powered by Hoogle
+- [x] **Hole-driven development powered by Hoogle**
 
 With the `<C-r>` keymap,
 the Hoogle search telescope integration can be used to fill holes.
 
 ![hoogleHole](https://user-images.githubusercontent.com/12857160/219751911-f45e4131-afad-47b3-b016-1d341c71c114.gif)
 
-#### GHCi repl
+- [x] **GHCi repl**
 
 Start a GHCi repl for the current project / buffer.
 
@@ -202,11 +201,11 @@ Start a GHCi repl for the current project / buffer.
 
 ![repl](https://user-images.githubusercontent.com/12857160/219758588-68f3c06f-5804-4279-b23d-1bdcc050d892.gif)
 
-#### Open project/package files for the current buffer
+- [x] **Open project/package files for the current buffer**
 
 ![commands](https://user-images.githubusercontent.com/12857160/219760916-06785cd5-f90a-4bb9-9ca8-94edbd655d46.gif)
 
-#### Hover actions
+- [x] **Hover actions**
 
 Inspired by [rust-tools.nvim](https://github.com/simrat39/rust-tools.nvim),
 this plugin adds the following hover actions (if available):
@@ -225,7 +224,7 @@ users can benefit from syntax highliting of code snippets.
 
 ![hoverActions](https://user-images.githubusercontent.com/12857160/219763211-61fc4207-4300-41f2-99c4-6a420cf940f2.gif)
 
-#### Automatically generate tags
+- [x] **Automatically generate tags**
 
 On attaching, Neovim's LSP client will set up [`tagfunc`](https://neovim.io/doc/user/lsp.html#vim.lsp.tagfunc())
 to query the language server for locations to jump to.
@@ -239,7 +238,20 @@ this plugin will set up `autocmd`s to automatically generate tags:
 
 This feature can be tweaked or disabled in the [advanced configuration](#advanced-configuration).
 
-### Planned
+- [x] **Auto-detect `haskell-debug-adapter` configurations**
+
+If the [`nvim-dap`](https://github.com/mfussenegger/nvim-dap) plugin is installed,
+you can use `haskell-tools.nvim` to auto-detect [`haskell-debug-adapter`](https://hackage.haskell.org/package/haskell-debug-adapter)
+configurations.
+
+![dap](https://user-images.githubusercontent.com/12857160/232348888-4fea5393-d624-417e-b994-6eb44113a3d9.gif)
+
+>**Note**
+>
+>`haskell-debug-adapter` is an experimental design and implementation of
+>a debug adapter for Haskell.
+
+- [ ] **Planned**
 
 For planned features, refer to the [issues](https://github.com/MrcJkb/haskell-tools.nvim/issues?q=is%3Aopen+is%3Aissue+label%3Aenhancement).
 
@@ -312,6 +324,9 @@ require('haskell-tools').start_or_attach {
       -- Events to trigger package tag generation
       package_events = { 'BufWritePost' },
     },
+    dap = {
+      cmd = { 'haskell-debug-adapter' },
+    },
   },
   hls = { -- LSP client options
     -- ...
@@ -427,6 +442,14 @@ iron.setup {
 }
 ```
 
+### Create `haskell-debug-adapter` launch configurations
+
+There are two ways this plugin will detect `haskell-debug-adapter` launch configurations:
+
+1. Automatically, by parsing Cabal or Stack project files.
+1. By loading a [`launch.json`](https://github.com/phoityne/hdx4vsc/tree/master/configs)
+  file in the project root.
+
 ### Available functions and commands
 
 For a complete overview, enter `:help haskell-tools` in Neovim.
@@ -517,10 +540,10 @@ ht.project.open_package_yaml()
 ht.project.open_package_cabal()
 
 -- Search for files within the current (sub)package
--- `opts`: Optional telescope.nvim find_files options
+---@param opts: Optional telescope.nvim `find_files` options
 ht.project.telescope_package_files(opts)
 -- Live grep within the current (sub)package
--- `opts`: Optional telescope.nvim live_grep options
+---@param opts: Optional telescope.nvim `live_grep` options
 ht.project.telescope_package_grep(opts)
 ```
 
@@ -532,14 +555,14 @@ The following functions depend on [`fast-tags`](https://github.com/elaforge/fast
 local ht = require('haskell-tools')
 
 -- Generate tags for the whole project
--- `path`: An optional file path, defaults to the current buffer
--- `opts`: Optional options:
--- `opts.refresh`: Whether to refresh tags
---                 if they have already been generated for a project
+---@param path: An optional file path, defaults to the current buffer
+---@param opts: Optional options:
+---@param opts.refresh: Whether to refresh tags
+--- if they have already been generated for a project
 ht.tags.generate_project_tags(path, opts)
 
 -- Generate tags for the whole project
--- `path`: An optional file path, defaults to the current buffer
+---@param path: An optional file path, defaults to the current buffer
 ht.tags.generate_package_tags(path)
 ```
 
@@ -562,6 +585,20 @@ To load the extension, call
 require('telescope').load_extension('ht')
 ```
 
+#### DAP
+
+```lua
+local ht = require('haskell-tools')
+
+---@param bufnr integer The buffer number
+---@param opts table? Optional
+---@param opts.autodetect: (boolean)
+--- Whether to auto-detect launch configurations
+---@param opts.settings_file_pattern: (string)
+--- File name or pattern to search for. Defaults to 'launch.json'
+ht.dap.discover_configurations(bufnr, opts)
+```
+
 ## Troubleshooting
 
 For a health check, run `:checkhealth haskell-tools`

doc/haskell-tools.txt

@@ -5,6 +5,7 @@ Introduction ·································
 The haskell-tools module ······································· |haskell-tools|
 haskell-tools configuration ····························· |haskell-tools.config|
 haskell-tools LSP client setup ····························· |haskell-tools.lsp|
+haskell-tools nvim-dap setup ······························· |haskell-tools.dap|
 haskell-tools Hoogle search ····························· |haskell-tools.hoogle|
 haskell-tools GHCi REPL module ···························· |haskell-tools.repl|
 haskell-tools Project module ··························· |haskell-tools.project|
@@ -98,6 +99,7 @@ HTOpts                                                                  *HTOpts*
     Fields: ~
         {tools}  (ToolsOpts)             haskell-tools plugin options
         {hls}    (HaskellLspClientOpts)  haskell-language-server client options
+        {dap}    (HTDapOpts)             haskell-debug-adapter client options
 
 
 ToolsOpts                                                            *ToolsOpts*
@@ -201,6 +203,15 @@ HaskellLspClientOpts                                      *HaskellLspClientOpts*
         |https://haskell-language-server.readthedocs.io/en/latest/configuration.html.|
 
 
+HTDapOpts                                                            *HTDapOpts*
+    @comment To print all options that are available for your haskell-language-server version, run `haskell-language-server-wrapper generate-default-config`
+
+    Fields: ~
+        {cmd}       (string[])                          The command to start haskell-debug-adapter with.
+        {logFile}   (string)                            Log file path for detected configurations.
+        {logLevel}  ("Debug"|"Info"|"Warning"|"Error")  The log level for detected configurations.
+
+
 config.defaults                                                *config.defaults*
 
     Type: ~
@@ -300,6 +311,35 @@ lsp.buf_eval_all({bufnr})                                     *lsp.buf_eval_all*
         (nil)
 
 
+==============================================================================
+haskell-tools nvim-dap setup                                 *haskell-tools.dap*
+
+AddDapConfigOpts                                              *AddDapConfigOpts*
+
+    Fields: ~
+        {autodetect}             (boolean)  Whether ta automatically detect launch configurations for the project
+        {settings_file_pattern}  (string)   File name or pattern to search for. Defaults to 'launch.json'
+
+
+                                                   *dap.discover_configurations*
+dap.discover_configurations({bufnr}, {opts})
+    Discover nvim-dap launch configurations for haskell-debug-adapter.
+
+    Parameters: ~
+        {bufnr}  (number|nil)            The buffer number
+        {opts}   (AddDapConfigOpts|nil)
+
+    Returns: ~
+        (nil)
+
+
+dap.setup()                                                          *dap.setup*
+    Setup the DAP module. Called by the haskell-tools setup.
+
+    Returns: ~
+        (nil)
+
+
 ==============================================================================
 haskell-tools Hoogle search                               *haskell-tools.hoogle*
 

flake.nix

@@ -135,7 +135,7 @@
       formatting = pre-commit-check-for system;
       inherit
         (checkPkgs)
-        lints
+        typecheck
         haskell-tools-test
         haskell-tools-test-no-hls
         haskell-tools-test-no-telescope

lua/haskell-tools/config.lua

@@ -3,6 +3,7 @@
 ---@class HTOpts
 ---@field tools ToolsOpts haskell-tools plugin options
 ---@field hls HaskellLspClientOpts haskell-language-server client options
+---@field dap HTDapOpts haskell-debug-adapter client options
 
 ---@class ToolsOpts
 ---@field codeLens CodeLensOpts LSP client codeLens options
@@ -66,6 +67,11 @@
 ---@see https://haskell-language-server.readthedocs.io/en/latest/configuration.html.
 ---@comment To print all options that are available for your haskell-language-server version, run `haskell-language-server-wrapper generate-default-config`
 
+---@class HTDapOpts
+---@field cmd string[] The command to start haskell-debug-adapter with.
+---@field logFile string Log file path for detected configurations.
+---@field logLevel 'Debug' | 'Info' | 'Warning' | 'Error' The log level for detected configurations.
+
 local ht = require('haskell-tools')
 local deps = require('haskell-tools.deps')
 
@@ -241,6 +247,12 @@ config.defaults = {
       },
     },
   },
+  ---@type HTDapOpts
+  dap = {
+    cmd = { 'haskell-debug-adapter' },
+    logFile = vim.fn.stdpath('data') .. '/haskell-dap.log',
+    logLevel = 'Warning',
+  },
 }
 
 ---@type HTOpts