resolve assign destructure (#1803)

Co-authored-by: Techatrix <[email protected]>

src/analysis.zig

@@ -3660,7 +3660,24 @@ pub const DeclWithHandle = struct {
                 })) orelse return null,
                 .Single,
             ),
-            .assign_destructure => null, // TODO
+            .assign_destructure => |pay| {
+                const type_node = pay.getFullVarDecl(tree).ast.type_node;
+                if (type_node != 0) {
+                    if (try analyser.resolveTypeOfNode(.{
+                        .node = type_node,
+                        .handle = self.handle,
+                    })) |ty| return try ty.instanceTypeVal(analyser);
+                }
+                const node = try analyser.resolveTypeOfNode(.{
+                    .node = tree.nodes.items(.data)[pay.node].rhs,
+                    .handle = self.handle,
+                }) orelse return null;
+                return switch (node.data) {
+                    .array => |array_info| try array_info.elem_ty.instanceTypeVal(analyser),
+                    .other => try analyser.resolveTupleFieldType(node, pay.index),
+                    else => null,
+                };
+            },
             .label_decl => |decl| try analyser.resolveTypeOfNodeInternal(.{
                 .node = decl.block,
                 .handle = self.handle,

tests/lsp_features/hover.zig

@@ -666,6 +666,60 @@ test "var decl alias" {
     );
 }
 
+test "hover - destructuring" {
+    try testHover(
+        \\fn func() void {
+        \\    const f<cursor>oo, const bar = .{ 1, 2 };
+        \\}
+    ,
+        \\```zig
+        \\foo
+        \\```
+        \\```zig
+        \\(comptime_int)
+        \\```
+    );
+    try testHover(
+        \\fn func() void {
+        \\    const foo, const b<cursor>ar, const baz = .{ 1, 2, 3 };
+        \\}
+    ,
+        \\```zig
+        \\bar
+        \\```
+        \\```zig
+        \\(comptime_int)
+        \\```
+    );
+    try testHover(
+        \\fn thing() !struct {usize, isize} {
+        \\    return .{1, 2};
+        \\}
+        \\fn ex() void {
+        \\    const f<cursor>oo, const bar = try thing();
+        \\}
+    ,
+        \\```zig
+        \\foo
+        \\```
+        \\```zig
+        \\(usize)
+        \\```
+    );
+    try testHover(
+        \\fn func() void {
+        \\    const foo, const b<cursor>ar: u32, const baz = undefined;
+        \\}
+    ,
+        \\```zig
+        \\bar
+        \\```
+        \\```zig
+        \\(u32)
+        \\```
+    );
+}
+
 // https://github.com/zigtools/zls/issues/1378
 test "type reference cycle" {
     try testHover(