From 63d84855a5a3f83b6b22f95e5502b683e4604609 Mon Sep 17 00:00:00 2001
From: InKryption <inkryption07@gmail.com>
Date: Fri, 19 Aug 2022 13:23:54 +0200
Subject: [PATCH] Improve unused variable report accuracy

---
 src/Server.zig | 25 ++++++++++++++++++++++---
 1 file changed, 22 insertions(+), 3 deletions(-)

diff --git a/src/Server.zig b/src/Server.zig
index c0564ae..b9b53dd 100644
--- a/src/Server.zig
+++ b/src/Server.zig
@@ -250,7 +250,7 @@ fn publishDiagnostics(server: *Server, writer: anytype, handle: DocumentStore.Ha
             while (decl_iterator.next()) |decl| {
                 var identifier_count: usize = 0;
 
-                var name_token_index = switch (decl.value_ptr.*) {
+                const name_token_index = switch (decl.value_ptr.*) {
                     .ast_node => |an| s: {
                         const an_tag = tree.nodes.items(.tag)[an];
                         switch (an_tag) {
@@ -270,8 +270,27 @@ fn publishDiagnostics(server: *Server, writer: anytype, handle: DocumentStore.Ha
                 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;
+                const tags = tree.tokens.items(.tag)[pit_start..pit_end];
+                for (tags) |tag, index| {
+                    if (tag != .identifier) continue;
+                    if (!std.mem.eql(u8, tree.tokenSlice(pit_start + @intCast(u32, index)), tree.tokenSlice(name_token_index))) continue;
+                    if (index -| 1 > 0 and tags[index - 1] == .period) continue;
+                    if (index +| 2 < tags.len and tags[index + 1] == .colon) switch (tags[index + 2]) {
+                        .l_brace,
+                        .keyword_inline,
+                        .keyword_while,
+                        .keyword_for,
+                        .keyword_switch,
+                        => continue,
+                        else => {},
+                    };
+                    if (index -| 2 > 0 and tags[index - 1] == .colon) switch (tags[index - 2]) {
+                        .keyword_break,
+                        .keyword_continue,
+                        => continue,
+                        else => {},
+                    };
+                    identifier_count += 1;
                 }
 
                 if (identifier_count <= 1)