Merge pull request #339 from jose-elias-alvarez/on-save-handling

feat: migrate to diagnostic API and support linting on save (feat. golangci-lint)

README.md

@@ -24,8 +24,9 @@ for external processes.
 null-ls is in **beta status**. Please see below for steps to follow if something
 doesn't work the way you expect (or doesn't work at all).
 
-At the moment, null-is is compatible with Neovim 0.5 (stable) and 0.6 (head),
-but you'll get the best experience from the latest version you can run.
+At the moment, null-is is compatible with Neovim 0.5.1 (stable) and 0.6 (head),
+but some features and performance improvements are exclusive to the latest
+version.
 
 Note that null-ls development takes place primarily on macOS and Linux and may
 not work as expected (or at all) on Windows. Contributions to expand Windows
@@ -287,6 +288,8 @@ The test suite includes unit and integration tests and depends on plenary.nvim.
 Run `make test` in the root of the project to run the suite or
 `FILE=filename_spec.lua make test-file` to test an individual file.
 
+E2E tests expect the latest Neovim master.
+
 ## Alternatives
 
 - [efm-langserver](https://github.com/mattn/efm-langserver) and

doc/BUILTINS.md

@@ -1888,6 +1888,32 @@ local sources = { null_ls.builtins.diagnostics.yamllint }
 - `command = "yamllint"`
 - `args = { "--format", "parsable", "-" }`
 
+### Diagnostics on save
+
+**NOTE**: These sources depend on Neovim version 0.6.0 and are not compatible
+with previous versions.
+
+These sources run **only** on save, meaning that the diagnostics you see will
+not reflect changes to the buffer until you write the changes to the disk.
+
+#### [golangci-lint](https://golangci-lint.run/)
+
+##### About
+
+A Go linter aggregator.
+
+##### Usage
+
+```lua
+local sources = { null_ls.builtins.diagnostics.golangci_lint }
+```
+
+##### Defaults
+
+- `filetypes = { "go" }`
+- `command = "golangci-lint"`
+- `args = { "run", "--fix=false", "--fast", "--out-format=json", "$DIRNAME", "--path-prefix", "$ROOT" }`
+
 ### Code actions
 
 #### [gitsigns.nvim](https://github.com/lewis6991/gitsigns.nvim)
@@ -2008,7 +2034,7 @@ following snippet:
 runtime_condit
 ```
 
-#### Vsnip
+#### [vim-vsnip](https://github.com/hrsh7th/vim-vsnip)
 
 ##### About
 
@@ -2020,4 +2046,6 @@ Snippets managed by [vim-vsnip](https://github.com/hrsh7th/vim-vsnip).
 local sources = { null_ls.builtins.completion.vsnip }
 ```
 
-Registering this source will show available snippets in the completion list, but vim-vsnip is responsible for expanding them. See [vim-vsnip's documentation for setup instructions](https://github.com/hrsh7th/vim-vsnip#2-setting).
+Registering this source will show available snippets in the completion list, but
+vim-vsnip is in charge of expanding them. See [vim-vsnip's documentation for
+setup instructions](https://github.com/hrsh7th/vim-vsnip#2-setting).

lua/null-ls/builtins/diagnostics/golangci_lint.lua

@@ -0,0 +1,44 @@
+local h = require("null-ls.helpers")
+local methods = require("null-ls.methods")
+
+local DIAGNOSTICS_ON_SAVE = methods.internal.DIAGNOSTICS_ON_SAVE
+
+return h.make_builtin({
+    method = DIAGNOSTICS_ON_SAVE,
+    filetypes = { "go" },
+    generator_opts = {
+        command = "golangci-lint",
+        to_stdin = true,
+        from_stderr = false,
+        args = {
+            "run",
+            "--fix=false",
+            "--fast",
+            "--out-format=json",
+            "$DIRNAME",
+            "--path-prefix",
+            "$ROOT",
+        },
+        format = "json",
+        check_exit_code = function(code)
+            return code <= 2
+        end,
+        on_output = function(params)
+            local diags = {}
+            local issues = params.output["Issues"]
+            if type(issues) == "table" then
+                for _, d in ipairs(issues) do
+                    if d.Pos.Filename == params.bufname then
+                        table.insert(diags, {
+                            row = d.Pos.Line,
+                            col = d.Pos.Column,
+                            message = d.Text,
+                        })
+                    end
+                end
+            end
+            return diags
+        end,
+    },
+    factory = h.generator_factory,
+})

lua/null-ls/config.lua

@@ -7,6 +7,8 @@ local defaults = {
     debug = false,
     -- prevent double setup
     _setup = false,
+    -- force using LSP handler, even when native API is available (e.g diagnostics)
+    _use_lsp_handler = false,
 }
 
 local config = vim.deepcopy(defaults)

lua/null-ls/diagnostics.lua

@@ -5,8 +5,16 @@ local methods = require("null-ls.methods")
 
 local api = vim.api
 
+local should_use_diagnostic_api = function()
+    return vim.diagnostic and not c.get()._use_lsp_handler
+end
+
+local namespaces = {}
+
 local M = {}
 
+M.namespaces = namespaces
+
 -- assume 1-indexed ranges
 local convert_range = function(diagnostic)
     local row = tonumber(diagnostic.row or 1)
@@ -23,7 +31,17 @@ local convert_range = function(diagnostic)
 end
 
 local postprocess = function(diagnostic, _, generator)
-    diagnostic.range = convert_range(diagnostic)
+    local range = convert_range(diagnostic)
+    -- the diagnostic API requires 0-indexing, so we can repurpose the LSP range
+    if should_use_diagnostic_api() then
+        diagnostic.lnum = range["start"].line
+        diagnostic.end_lnum = range["end"].line
+        diagnostic.col = range["start"].character
+        diagnostic.end_col = range["end"].character
+    else
+        diagnostic.range = range
+    end
+
     diagnostic.source = diagnostic.source or generator.opts.name or generator.opts.command or "null-ls"
 
     local formatted = generator and generator.opts.diagnostics_format or c.get().diagnostics_format
@@ -38,6 +56,23 @@ local postprocess = function(diagnostic, _, generator)
     diagnostic.message = formatted
 end
 
+local handle_diagnostics = function(diagnostics, uri, bufnr, client_id)
+    if should_use_diagnostic_api() then
+        for id, by_id in pairs(diagnostics) do
+            namespaces[id] = namespaces[id] or api.nvim_create_namespace("NULL_LS_SOURCE_" .. id)
+            vim.diagnostic.set(namespaces[id], bufnr, by_id)
+        end
+        return
+    end
+
+    local handler = u.resolve_handler(methods.lsp.PUBLISH_DIAGNOSTICS)
+    handler(nil, { diagnostics = diagnostics, uri = uri }, {
+        method = methods.lsp.PUBLISH_DIAGNOSTICS,
+        client_id = client_id,
+        bufnr = bufnr,
+    })
+end
+
 -- track last changedtick to only send most recent diagnostics
 local last_changedtick = {}
 
@@ -57,18 +92,24 @@ M.handler = function(original_params)
         s.clear_cache(uri)
     end
 
-    local params = u.make_params(original_params, methods.map[method])
-    local handler = u.resolve_handler(methods.lsp.PUBLISH_DIAGNOSTICS)
     local bufnr = vim.uri_to_bufnr(uri)
-
     local changedtick = original_params.textDocument.version or api.nvim_buf_get_changedtick(bufnr)
+
+    if method == methods.lsp.DID_SAVE and changedtick == last_changedtick[uri] then
+        u.debug_log("buffer unchanged; ignoring didSave notification")
+        return
+    end
+
+    local params = u.make_params(original_params, methods.map[method])
+
     last_changedtick[uri] = changedtick
 
     require("null-ls.generators").run_registered({
         filetype = params.ft,
         method = methods.map[method],
         params = params,
         postprocess = postprocess,
+        index_by_id = should_use_diagnostic_api(),
         callback = function(diagnostics)
             u.debug_log("received diagnostics from generators")
             u.debug_log(diagnostics)
@@ -81,18 +122,7 @@ M.handler = function(original_params)
                 return
             end
 
-            if u.has_version("0.5.1") then
-                handler(nil, { diagnostics = diagnostics, uri = uri }, {
-                    method = methods.lsp.PUBLISH_DIAGNOSTICS,
-                    client_id = original_params.client_id,
-                    bufnr = bufnr,
-                })
-            else
-                handler(nil, methods.lsp.PUBLISH_DIAGNOSTICS, {
-                    diagnostics = diagnostics,
-                    uri = uri,
-                }, original_params.client_id, bufnr)
-            end
+            handle_diagnostics(diagnostics, uri, bufnr, original_params.client_id)
         end,
     })
 end

lua/null-ls/formatting.lua

@@ -66,12 +66,7 @@ M.apply_edits = function(edits, params)
 
     local marks, views = save_win_data(bufnr)
 
-    if u.has_version("0.5.1") then
-        handler(nil, diffed_edits, { method = params.lsp_method, client_id = params.client_id, bufnr = bufnr })
-    else
-        ---@diagnostic disable-next-line: redundant-parameter
-        handler(nil, params.lsp_method, diffed_edits, params.client_id, bufnr)
-    end
+    handler(nil, diffed_edits, { method = params.lsp_method, client_id = params.client_id, bufnr = bufnr })
 
     vim.schedule(function()
         restore_win_data(marks, views, bufnr)

lua/null-ls/generators.lua

@@ -2,7 +2,7 @@ local u = require("null-ls.utils")
 
 local M = {}
 
-M.run = function(generators, params, postprocess, callback)
+M.run = function(generators, params, postprocess, callback, should_index)
     local a = require("plenary.async")
 
     local runner = function()
@@ -14,7 +14,14 @@ M.run = function(generators, params, postprocess, callback)
         end
 
         local futures, all_results = {}, {}
-        for _, generator in ipairs(generators) do
+        local iterator = should_index and pairs or ipairs
+        for index, generator in iterator(generators) do
+            local to_insert = all_results
+            if should_index then
+                all_results[index] = {}
+                to_insert = all_results[index]
+            end
+
             table.insert(futures, function()
                 local copied_params = vim.deepcopy(params)
 
@@ -50,7 +57,7 @@ M.run = function(generators, params, postprocess, callback)
                         postprocess(result, copied_params, generator)
                     end
 
-                    table.insert(all_results, result)
+                    table.insert(to_insert, result)
                 end
             end)
         end
@@ -90,11 +97,11 @@ M.run_sequentially = function(generators, make_params, postprocess, callback, af
 end
 
 M.run_registered = function(opts)
-    local filetype, method, params, postprocess, callback =
-        opts.filetype, opts.method, opts.params, opts.postprocess, opts.callback
-    local generators = M.get_available(filetype, method)
+    local filetype, method, params, postprocess, callback, index_by_id =
+        opts.filetype, opts.method, opts.params, opts.postprocess, opts.callback, opts.index_by_id
+    local generators = M.get_available(filetype, method, index_by_id)
 
-    M.run(generators, params, postprocess, callback)
+    M.run(generators, params, postprocess, callback, index_by_id)
 end
 
 M.run_registered_sequentially = function(opts)
@@ -105,10 +112,14 @@ M.run_registered_sequentially = function(opts)
     M.run_sequentially(generators, make_params, postprocess, callback, after_all)
 end
 
-M.get_available = function(filetype, method)
+M.get_available = function(filetype, method, index_by_id)
     local available = {}
     for _, source in ipairs(require("null-ls.sources").get_available(filetype, method)) do
-        table.insert(available, source.generator)
+        if index_by_id then
+            available[source.id] = source.generator
+        else
+            table.insert(available, source.generator)
+        end
     end
     return available
 end

lua/null-ls/handlers.lua

@@ -15,33 +15,22 @@ end
 -- this will override a handler, batch results and debounce them
 function M.combine(method, ms)
     ms = ms or 100
-    local orig = u.resolve_handler(method)
-    local is_new = u.has_version("0.5.1")
 
+    local orig = u.resolve_handler(method)
     local all_results = {}
 
     local handler = u.debounce(ms, function()
         if #all_results > 0 then
-            if is_new then
-                pcall(orig, nil, all_results)
-            else
-                pcall(orig, nil, nil, all_results)
-            end
+            pcall(orig, nil, all_results)
             all_results = {}
         end
     end)
 
-    if is_new then
-        vim.lsp.handlers[method] = function(_, results)
-            vim.list_extend(all_results, results or {})
-            handler()
-        end
-    else
-        vim.lsp.handlers[method] = function(_, _, results)
-            vim.list_extend(all_results, results or {})
-            handler()
-        end
+    vim.lsp.handlers[method] = function(_, results)
+        vim.list_extend(all_results, results or {})
+        handler()
     end
+
     return vim.lsp.handlers[method]
 end
 

lua/null-ls/lspconfig.lua

@@ -19,7 +19,7 @@ local should_attach = function(bufnr)
 
     local ft = api.nvim_buf_get_option(bufnr, "filetype")
     -- writing and immediately deleting a buffer (e.g. :wq from a git commit)
-    -- triggers a bug on 0.5 which is fixed on master
+    -- triggers a bug on 0.5.1 which is fixed on master
     if ft == "gitcommit" and not u.has_version("0.6.0") then
         return false
     end