Add config option for unused vars

README.md

@@ -9,15 +9,27 @@ Zig Language Server, or `zls`, is a language server for Zig. The Zig wiki states
 ## Table Of Contents
 
 - [Installation](#installation)
-  - [Build Options](#build-options)
+  - [Installing binaries](#installing-binaries)
+    - [MacOS](#macos)
+    - [Linux](#linux)
+  - [From Source](#from-source)
+    - [Build Options](#build-options)
+    - [Updating Data Files](#updating-data-files)
   - [Configuration Options](#configuration-options)
-- [Usage](#usage)
+- [Features](#features)
   - [VSCode](#vscode)
   - [Sublime Text](#sublime-text)
+    - [Sublime Text 3](#sublime-text-3)
+    - [Sublime Text 4](#sublime-text-4)
   - [Kate](#kate)
   - [Neovim/Vim8](#neovimvim8)
+    - [CoC](#coc)
+    - [YouCompleteMe](#youcompleteme)
+    - [nvim-lspconfig](#nvim-lspconfig)
+    - [LanguageClient-neovim](#languageclient-neovim)
   - [Emacs](#emacs)
   - [Doom Emacs](#doom-emacs)
+  - [Spacemacs](#spacemacs)
 - [Related Projects](#related-projects)
 - [License](#license)
 
@@ -88,6 +100,7 @@ The following options are currently available.
 | Option | Type | Default value | What it Does |
 | --- | --- | --- | --- |
 | `enable_snippets` | `bool` | `false` | Enables snippet completions when the client also supports them. |
+| `enable_unused_variable_warnings` | `bool` | `false`| Enables warnings for local variables that aren't used. |
 | `zig_lib_path` | `?[]const u8` | `null` | zig library path, e.g. `/path/to/zig/lib/zig`, used to analyze std library imports. |
 | `zig_exe_path` | `?[]const u8` | `null` | zig executable path, e.g. `/path/to/zig/zig`, used to run the custom build runner. If `null`, zig is looked up in `PATH`. Will be used to infer the zig standard library path if none is provided. |
 | `warn_style` | `bool` | `false` | Enables warnings for style *guideline* mismatches |
@@ -125,7 +138,7 @@ Install the `zls-vscode` extension from [here](https://github.com/zigtools/zls-v
 - Install the `LSP` package from [here](https://github.com/sublimelsp/LSP/releases) or via Package Control.
 - Add this snippet to `LSP's` user settings:
 
-#### For Sublime Text 3:
+#### Sublime Text 3
 
 ```json
 {
@@ -141,7 +154,7 @@ Install the `zls-vscode` extension from [here](https://github.com/zigtools/zls-v
 }
 ```
 
-#### For Sublime Text 4:
+#### Sublime Text 4
 
 ```json
 {

src/Config.zig

@@ -3,6 +3,9 @@
 /// Whether to enable snippet completions
 enable_snippets: bool = false,
 
+/// Whether to enable unused variable warnings
+enable_unused_variable_warnings: bool = false,
+
 /// zig library path
 zig_lib_path: ?[]const u8 = null,
 

src/main.zig

@@ -229,46 +229,48 @@ fn publishDiagnostics(arena: *std.heap.ArenaAllocator, handle: DocumentStore.Han
         });
     }
 
-    for (handle.document_scope.scopes) |scope| {
+    if (config.enable_unused_variable_warnings) {
-        const scope_data = switch (scope.data) {
+        for (handle.document_scope.scopes) |scope| {
-            .function => |f| f,
+            const scope_data = switch (scope.data) {
-            .block => |b| b,
+                .function => |f| f,
-            else => continue,
+                .block => |b| b,
-        };
-
-        var decl_iterator = scope.decls.iterator();
-        while (decl_iterator.next()) |decl| {
-            var identifier_count: usize = 0;
-
-            var name_token_index = switch (decl.value_ptr.*) {
-                .ast_node => |an| s: {
-                    const an_tag = tree.nodes.items(.tag)[an];
-                    switch (an_tag) {
-                        .simple_var_decl => {
-                            break :s tree.nodes.items(.main_token)[an] + 1;
-                        },
-                        else => continue,
-                    }
-                },
-                .param_decl => |param| param.name_token orelse continue,
                 else => continue,
             };
 
-            const pit_start = tree.firstToken(scope_data);
+            var decl_iterator = scope.decls.iterator();
-            const pit_end = ast.lastToken(tree, scope_data);
+            while (decl_iterator.next()) |decl| {
+                var identifier_count: usize = 0;
 
-            for (tree.tokens.items(.tag)[pit_start..pit_end]) |tag, index| {
+                var name_token_index = switch (decl.value_ptr.*) {
-                if (tag == .identifier and std.mem.eql(u8, tree.tokenSlice(pit_start + @intCast(u32, index)), tree.tokenSlice(name_token_index))) identifier_count += 1;
+                    .ast_node => |an| s: {
+                        const an_tag = tree.nodes.items(.tag)[an];
+                        switch (an_tag) {
+                            .simple_var_decl => {
+                                break :s tree.nodes.items(.main_token)[an] + 1;
+                            },
+                            else => continue,
+                        }
+                    },
+                    .param_decl => |param| param.name_token orelse continue,
+                    else => continue,
+                };
+
+                const pit_start = tree.firstToken(scope_data);
+                const pit_end = ast.lastToken(tree, scope_data);
+
+                for (tree.tokens.items(.tag)[pit_start..pit_end]) |tag, index| {
+                    if (tag == .identifier and std.mem.eql(u8, tree.tokenSlice(pit_start + @intCast(u32, index)), tree.tokenSlice(name_token_index))) identifier_count += 1;
+                }
+
+                if (identifier_count <= 1)
+                    try diagnostics.append(.{
+                        .range = astLocationToRange(tree.tokenLocation(0, name_token_index)),
+                        .severity = .Error,
+                        .code = "unused_variable",
+                        .source = "zls",
+                        .message = "Unused variable! Either remove the variable or use '_ = ' on the variable to bypass this error.",
+                    });
             }
-
-            if (identifier_count <= 1)
-                try diagnostics.append(.{
-                    .range = astLocationToRange(tree.tokenLocation(0, name_token_index)),
-                    .severity = .Error,
-                    .code = "unused_variable",
-                    .source = "zls",
-                    .message = "Unused variable! Either remove the variable or use '_ = ' on the variable to bypass this error.",
-                });
         }
     }
 

src/requests.zig

@@ -263,6 +263,7 @@ pub const Configuration = struct {
     params: struct {
         settings: struct {
             enable_snippets: ?bool,
+            enable_unused_variable_warnings: ?bool,
             zig_lib_path: ?[]const u8,
             zig_exe_path: ?[]const u8,
             warn_style: ?bool,