Alire + ada_language_server + nvim

General
1

Hello,

Has anyone been able to get ada_language_server working with nvim using an Alire project? By ‘working’ I mean use alire to fetch and build a project. Then be able to edit the project source files with language server protocol features (navigation, tooltips, etc.) with nvim.

I used alire to fetch and build the “magic_hat” project using:

alr get mage_hat
cd mage_hat_0.3.0_255dc372
alr build

For nvim, ALS has been installed and my ‘init.lua’ has the following config code in it:

require('lspconfig').als.setup{
    settings = {
        ada = {
            projectFile = "mage_hat.gpr"
        }
    }
}

When I open the ‘mage_hat.adb’ which is in the src folder of the mage_hat alire project I would expect the ALS to be operational but I am seeing errors in the ALS logs:

[ALS.MAIN] On_DidOpenTextDocument_Notification: file:///home/nintendo/Desktop/mage_hat_0.3.0_255dc372/src/mage_hat.adb                                                
  [ALS.IN] {"id":2,"params":{"textDocument":{"uri":"file:\/\/\/home\/nintendo\/Desktop\/mage_hat_0.3.0_255dc372\/src\/mage_hat.adb"}},"jsonrpc":"2.0","method":"textDocument\/semanticTokens\/full"}
  [ALS.MAIN] Document_Tokens_Full_Request: Request  2 file:///home/nintendo/Desktop/mage_hat_0.3.0_255dc372/src/mage_hat.adb                                             
  [ALS.MAIN.EXCEPTIONS] Unexpected exception: raised GNATCOLL.PROJECTS.INVALID_PROJECT : gnatcoll-projects.adb:7714
  _ALS.MAIN.EXCEPTIONS_ [/home/nintendo/.local/share/nvim/mason/bin/../../../../..//.local/share/alire/builds/gnatcoll_23.0.0_29478a20/30653702b467e53c8eee88abe2cde92767b6a0290a3d01a6e2dca2a07b06501b/lib/gnatcoll/relocatable/libgnatcoll.so.23.0.0  ]                                                        
  _ALS.MAIN.EXCEPTIONS_ 0x7d8000a41d02 gnatcoll__projects__load at ???                                                                                                   
  _ALS.MAIN.EXCEPTIONS_ [/home/nintendo/.local/share/nvim/mason/bin/ada_language_server]
  _ALS.MAIN.EXCEPTIONS_ 0x11c7b5a Lsp.Ada_Handlers.Load_Project at lsp-ada_handlers.adb:4877                                                                             
  _ALS.MAIN.EXCEPTIONS_ 0x116379b Lsp.Ada_Handlers.On_Didchangeconfiguration_Notification at lsp-ada_handlers.adb:4492
  _ALS.MAIN.EXCEPTIONS_ 0xe9ed6e Lsp.Messages.Server_Notifications.Visit at lsp-messages-server_notifications.adb:55                                                     
  _ALS.MAIN.EXCEPTIONS_ 0x10a5c6d Lsp.Servers.Processing_Task_Type.Process_Message at lsp-servers.adb:1198
  _ALS.MAIN.EXCEPTIONS_ 0x10a52b6 Lsp.Servers.Processing_Task_TypeT at lsp-servers.adb:1291                                                                              
  _ALS.MAIN.EXCEPTIONS_ [/home/nintendo/.local/share/nvim/mason/bin/../../../../..//.local/share/alire/toolchains/gnat_native_13.2.2_a27fd794/lib/gcc/x86_64-pc-linux-gnu/13.2.0/adalib/libgnarl-13.so]
  _ALS.MAIN.EXCEPTIONS_ 0x7d8000cc5438 System.Tasking.Stages.Task_Wrapper at s-tassta.adb:1211                                                                            
  _ALS.MAIN.EXCEPTIONS_ [/lib/x86_64-linux-gnu/libc.so.6]  
  _ALS.MAIN.EXCEPTIONS_ 0x7d7ffea94ac1                                                                                                                                     
  _ALS.MAIN.EXCEPTIONS_ 0x7d7ffeb2684e                     
  _ALS.MAIN.EXCEPTIONS_ 0xfffffffffffffffe                                                                                                                                 
  [ALS.MAIN] Loading the implicit project            
  [ALS.MAIN] Show_Message: Unable to load project file: /home/nintendo/Desktop/mage_hat_0.3.0_255dc372/mage_hat.gpr
  _ALS.MAIN_ mage_hat.gpr:2:06: imported project file "mage.gpr" not found
  _ALS.MAIN_ mage_hat.gpr:17:32: unknown package or project "Mage"                                                                                                         
  _ALS.MAIN_ mage_hat.gpr:17:32: wrong expression kind for attribute "switches"
  _ALS.MAIN_ mage_hat_config.gpr:2:06: imported project file "mage.gpr" not found                                                                                          
  _ALS.MAIN_ mage_hat_config.gpr:2:06: imported by "/home/nintendo/Desktop/mage_hat_0.3.0_255dc372/config/mage_hat_config.gpr"
  _ALS.MAIN_ mage_hat_config.gpr:2:06: imported by "/home/nintendo/Desktop/mage_hat_0.3.0_255dc372/mage_hat.gpr"                                                                                                                                      
  [ALS.OUT] {"jsonrpc":"2.0","method":"window/showMessage","params":{"type":1,"message":"Unable to load project file: /home/nintendo/Desktop/mage_hat_0.3.0_255dc372/mage_hat.gpr\nmage_hat.gpr:2:06: imported project file \"mage.gpr\" not found\nma  ge_hat.gpr:17:32: unknown package or project \"Mage\"\nmage_hat.gpr:17:32: wrong expression kind for attribute \"switches\"\nmage_hat_config.gpr:2:06: imported project file \"mage.gpr\" not found\nmage_hat_config.gpr:2:06: imported by \"/home/n  intendo/Desktop/mage_hat_0.3.0_255dc372/config/mage_hat_config.gpr\"\nmage_hat_config.gpr:2:06: imported by \"/home/nintendo/Desktop/mage_hat_0.3.0_255dc372/mage_hat.gpr\"\n"}}
  [ALS.MAIN] RegisterCapability_Request: Request  2  1
  [ALS.MAIN] In Text_Document_Did_Open
  [ALS.MAIN] Uri : file:///home/nintendo/Desktop/mage_hat_0.3.0_255dc372/src/mage_hat.adb
  [ALS.OUT] {"jsonrpc":"2.0","id":2,"method":"client/registerCapability","params":{"registrations":[{"id":"rf","method":"textDocument/rangeFormatting","registerOptions":{"documentSelector":["ada"]}}]}}
  [ALS.MAIN] Finished Text_Document_Did_Open
  [ALS.MAIN] Publish_Diagnostics: file:///home/nintendo/Desktop/mage_hat_0.3.0_255dc372/src/mage_hat.adb 1
  [ALS.OUT] {"jsonrpc":"2.0","method":"textDocument/publishDiagnostics","params":{"uri":"file:///home/nintendo/Desktop/mage_hat_0.3.0_255dc372/src/mage_hat.adb","diagnostics":[{"range":{"start":{"line":0,"character":0},"end":{"line":0,"character"  :0}},"severity":1,"source":"project","message":"Project file has error and can't be loaded."}]}}
  [ALS.MAIN] SemanticTokens: Response  2  835

The errors in the ALS logs are similar to the errors I get if I try to build mage hat in the root folder without using Alire:

~/Desktop/mage_hat_0.3.0_255dc372$ gprbuild
using project file mage_hat.gpr
mage_hat.gpr:2:06: imported project file "mage.gpr" not found
mage_hat.gpr:17:32: unknown package or project "Mage"
mage_hat.gpr:17:32: wrong expression kind for attribute "switches"
mage_hat_config.gpr:2:06: imported project file "mage.gpr" not found
mage_hat_config.gpr:2:06: imported by "/home/nintendo/Desktop/mage_hat_0.3.0_255dc372/config/mage_hat_config.gpr"
mage_hat_config.gpr:2:06: imported by "/home/nintendo/Desktop/mage_hat_0.3.0_255dc372/mage_hat.gpr"
gprbuild: "mage_hat.gpr" processing failed

Any ideas would be greatly appreciated.

2

I have a more advanced (read: complex) setup, using neovim. I have tried on and off in the last three years to get ada_language_server working in that context, but it always ends up using 100% of the CPU forever. We have a large codebase (a few million lines of code), but that doesn’t explain it. As a customer, I have reported this to AdaCore but so far they haven’t been able to reproduce, and we haven’t been able to pinpoint the issue.

My setup starts similar to yours, except I provide an absolute paths for the project.

local function ada_on_attach(client, bufnr)
   --  For now, disable semantic tokens highlighting in Ada.  When this is
   --  enabled, the colors used for identifiers depend on information provided
   --  by LSP, but this seems wrong.  For instance, a 'with A.B' will highlight
   --  differently from a 'with A'.
   client.server_capabilities.semanticTokensProvider = nil
end

   local dot_git_finder = require('lspconfig').util.root_pattern('.git');
   local root_dir = dot_git_finder(vim.fn.getcwd())
   vim.g.ada_project = vim.fn.fnamemodify('everything.gpr', ':p')

   require('lspconfig').als.setup({
      on_attach = ada_on_attach,
      root_dir = dot_git_finder,
      settings = {
         ada = {
            projectFile = vim.g.ada_project,
            scenarioVariables = {
              arch= "x86-64",
     [...]
            }
      }
}

Then I also use Mason as neovim plugin, which automatically installs the latest version of ada_language_server. I install it, like all my plugins, via the lazy.vim plugin

   {
      "williamboman/mason.nvim",
      build = ":MasonUpdate",
      cmd = { "Mason" },
      opts = {},
   },

(then run :Mason and select ada_language_server in the list, to install it)

3

Also: the dependencies between my projects are always specified using relative paths. I do not depend on the GPR_PROJECT_PATH environment variable, which maybe is something different in your setup, since apparently gprbuild is not able to find the dependencies

4

Thanks for the example. This excerpt seems to work for a project file named ‘splat.gpr’. I’m not sure how to setup the config to automatically load any project without manually tinkering with the nvim config lua files for now.

󰌵 local function ada_on_attach(client, bufnr)      Unused local `bufnr`.   

     client.server_capabilities.semanticTokensProvider = nil   
  end   
      
     local dot_git_finder = require('lspconfig').util.root_pattern('.git');   
󰌵    local root_dir = dot_git_finder(vim.fn.getcwd())      Unused local `root_dir`.   
     vim.g.ada_project = vim.fn.fnamemodify('everything.gpr', ':p')   
      
     require('lspconfig').als.setup({   
     │  on_attach = ada_on_attach,   
     │  root_dir = dot_git_finder,   
     │  settings = {   
     │  │  ada = {   
     │  │  │  -- projectFile = vim.g.ada_project,   
     │  │  │  projectFile = 'splat.gpr',   
     │  │  │  scenarioVariables = {   
     │  │  │  │ arch= "x86-64",   
     │  │  │  }   
     │  │}   
     │}   
  })   
     ````