From 0c0cb261b7ce4669e37a4af84703f85c57ffb392 Mon Sep 17 00:00:00 2001
From: Auguste Rame <auguste.rame@gmail.com>
Date: Fri, 8 Jul 2022 20:29:53 +0200
Subject: [PATCH] Basic variable type resolution on hover

---
 src/analysis.zig |  9 +++++----
 src/main.zig     | 41 ++++++++++++++++++++++++++++++++++++-----
 2 files changed, 41 insertions(+), 9 deletions(-)

diff --git a/src/analysis.zig b/src/analysis.zig
index 4ae8b9f..2c8cbbe 100644
--- a/src/analysis.zig
+++ b/src/analysis.zig
@@ -494,7 +494,7 @@ fn resolveUnwrapErrorType(store: *DocumentStore, arena: *std.heap.ArenaAllocator
             .type = .{ .data = .{ .other = n }, .is_type_val = rhs.type.is_type_val },
             .handle = rhs.handle,
         },
-        .primitive, .slice, .pointer => return null,
+        .primitive, .slice, .pointer, .array_index => return null,
     };
 
     if (rhs.handle.tree.nodes.items(.tag)[rhs_node] == .error_union) {
@@ -670,7 +670,7 @@ pub fn resolveTypeOfNodeInternal(store: *DocumentStore, arena: *std.heap.ArenaAl
         .identifier => {
             if (isTypeIdent(handle.tree, main_tokens[node])) {
                 return TypeWithHandle{
-                    .type = .{ .data = .primitive, .is_type_val = true },
+                    .type = .{ .data = .{ .primitive = node }, .is_type_val = true },
                     .handle = handle,
                 };
             }
@@ -977,7 +977,8 @@ pub const Type = struct {
         slice: Ast.Node.Index,
         error_union: Ast.Node.Index,
         other: Ast.Node.Index,
-        primitive,
+        primitive: Ast.Node.Index,
+        array_index,
     },
     /// If true, the type `type`, the attached data is the value of the type value.
     is_type_val: bool,
@@ -1941,7 +1942,7 @@ pub const DeclWithHandle = struct {
                 bound_type_params,
             ),
             .array_index => TypeWithHandle{
-                .type = .{ .data = .primitive, .is_type_val = false },
+                .type = .{ .data = .array_index, .is_type_val = false },
                 .handle = self.handle,
             },
             .label_decl => return null,
diff --git a/src/main.zig b/src/main.zig
index ef5c6b4..f4cc653 100644
--- a/src/main.zig
+++ b/src/main.zig
@@ -404,7 +404,7 @@ fn typeToCompletion(
             null,
             config,
         ),
-        .primitive => {},
+        .primitive, .array_index => {},
     }
 }
 
@@ -736,19 +736,50 @@ fn hoverSymbol(id: types.RequestId, arena: *std.heap.ArenaAllocator, decl_handle
         .label_decl => |label_decl| tree.tokenSlice(label_decl),
     };
 
+    var bound_type_params = analysis.BoundTypeParams.init(arena.allocator());
+    const resolved_type = try decl_handle.resolveType(&document_store, arena, &bound_type_params);
+
+    const resolved_type_str = if (resolved_type) |rt|
+        if (rt.type.is_type_val) "type" else switch (rt.type.data) {
+            .pointer,
+            .slice,
+            .error_union,
+            .primitive,
+            => |p| tree.getNodeSource(p),
+            .other => |p| switch (tree.nodes.items(.tag)[p]) {
+                .container_decl,
+                .container_decl_arg,
+                .container_decl_arg_trailing,
+                .container_decl_trailing,
+                .container_decl_two,
+                .container_decl_two_trailing,
+                .tagged_union,
+                .tagged_union_trailing,
+                .tagged_union_two,
+                .tagged_union_two_trailing,
+                .tagged_union_enum_tag,
+                .tagged_union_enum_tag_trailing,
+                => tree.tokenSlice(tree.nodes.items(.main_token)[p] - 2), // NOTE: This is a hacky nightmare but it works :P
+                else => tree.getNodeSource(p),
+            },
+            else => "unknown",
+        }
+    else
+        "unknown";
+
     var hover_text: []const u8 = undefined;
     if (hover_kind == .Markdown) {
         hover_text =
             if (doc_str) |doc|
-            try std.fmt.allocPrint(arena.allocator(), "```zig\n{s}\n```\n{s}", .{ def_str, doc })
+            try std.fmt.allocPrint(arena.allocator(), "```zig\n{s}\n```\n```zig\n({s})\n```\n{s}", .{ def_str, resolved_type_str, doc })
         else
-            try std.fmt.allocPrint(arena.allocator(), "```zig\n{s}\n```", .{def_str});
+            try std.fmt.allocPrint(arena.allocator(), "```zig\n{s}\n```\n```zig\n({s})\n```", .{ def_str, resolved_type_str });
     } else {
         hover_text =
             if (doc_str) |doc|
-            try std.fmt.allocPrint(arena.allocator(), "{s}\n{s}", .{ def_str, doc })
+            try std.fmt.allocPrint(arena.allocator(), "{s} ({s})\n{s}", .{ def_str, resolved_type_str, doc })
         else
-            def_str;
+            try std.fmt.allocPrint(arena.allocator(), "{s} ({s})", .{ def_str, resolved_type_str });
     }
 
     try send(arena, types.Response{