From ef95c76e458209e3da92beea8375ca7f2552e4a2 Mon Sep 17 00:00:00 2001
From: Alexandros Naskos <alex_naskos@hotmail.com>
Date: Wed, 3 Jun 2020 11:23:14 +0300
Subject: [PATCH] Added doc comments on hover

---
 src/analysis.zig | 44 +++++++++++++++++---------------------------
 src/main.zig     | 12 +++++++++---
 src/types.zig    |  7 +------
 3 files changed, 27 insertions(+), 36 deletions(-)

diff --git a/src/analysis.zig b/src/analysis.zig
index f4fbc41..af6d6b5 100644
--- a/src/analysis.zig
+++ b/src/analysis.zig
@@ -20,39 +20,29 @@ pub fn getFunctionByName(tree: *ast.Tree, name: []const u8) ?*ast.Node.FnProto {
     return null;
 }
 
-/// Gets a function's doc comments, caller must free memory when a value is returned
+/// Get a declaration's doc comment node
+fn getDocCommentNode(tree: *ast.Tree, node: *ast.Node) ?*ast.Node.DocComment {
+    if (node.cast(ast.Node.FnProto)) |func| {
+        return func.doc_comments;
+    } else if (node.cast(ast.Node.VarDecl)) |var_decl| {
+        return var_decl.doc_comments;
+    } else if (node.cast(ast.Node.ContainerField)) |field| {
+        return field.doc_comments;
+    } else if (node.cast(ast.Node.ErrorTag)) |tag| {
+        return tag.doc_comments;
+    }
+    return null;
+}
+
+/// Gets a declaration's doc comments, caller must free memory when a value is returned
 /// Like:
 ///```zig
 ///var comments = getFunctionDocComments(allocator, tree, func);
 ///defer if (comments) |comments_pointer| allocator.free(comments_pointer);
 ///```
 pub fn getDocComments(allocator: *std.mem.Allocator, tree: *ast.Tree, node: *ast.Node) !?[]const u8 {
-    switch (node.id) {
-        .FnProto => {
-            const func = node.cast(ast.Node.FnProto).?;
-            if (func.doc_comments) |doc_comments| {
-                return try collectDocComments(allocator, tree, doc_comments);
-            }
-        },
-        .VarDecl => {
-            const var_decl = node.cast(ast.Node.VarDecl).?;
-            if (var_decl.doc_comments) |doc_comments| {
-                return try collectDocComments(allocator, tree, doc_comments);
-            }
-        },
-        .ContainerField => {
-            const field = node.cast(ast.Node.ContainerField).?;
-            if (field.doc_comments) |doc_comments| {
-                return try collectDocComments(allocator, tree, doc_comments);
-            }
-        },
-        .ErrorTag => {
-            const tag = node.cast(ast.Node.ErrorTag).?;
-            if (tag.doc_comments) |doc_comments| {
-                return try collectDocComments(allocator, tree, doc_comments);
-            }
-        },
-        else => {},
+    if (getDocCommentNode(tree, node)) |doc_comment_node| {
+        return try collectDocComments(allocator, tree, doc_comment_node);
     }
     return null;
 }
diff --git a/src/main.zig b/src/main.zig
index f986dcb..d74f50e 100644
--- a/src/main.zig
+++ b/src/main.zig
@@ -231,7 +231,7 @@ fn nodeToCompletion(
     node: *std.zig.ast.Node,
     config: Config,
 ) error{OutOfMemory}!void {
-    var doc = if (try analysis.getDocComments(list.allocator, analysis_ctx.tree(), node)) |doc_comments|
+    const doc = if (try analysis.getDocComments(list.allocator, analysis_ctx.tree(), node)) |doc_comments|
         types.MarkupContent{
             .kind = .Markdown,
             .value = doc_comments,
@@ -359,7 +359,12 @@ fn gotoDefinitionSymbol(id: i64, analysis_ctx: *DocumentStore.AnalysisContext, d
 fn hoverSymbol(id: i64, analysis_ctx: *DocumentStore.AnalysisContext, decl: *std.zig.ast.Node) !void {
     const result = try resolveVarDeclFnAlias(analysis_ctx, decl);
 
-    const str_value = switch (result.decl.id) {
+    const doc_str = if (try analysis.getDocComments(&analysis_ctx.arena.allocator, result.analysis_ctx.tree(), result.decl)) |str|
+        str
+    else
+        "";
+
+    const signature_str = switch (result.decl.id) {
         .VarDecl => blk: {
             const var_decl = result.decl.cast(std.zig.ast.Node.VarDecl).?;
             break :blk analysis.getVariableSignature(result.analysis_ctx.tree(), var_decl);
@@ -371,11 +376,12 @@ fn hoverSymbol(id: i64, analysis_ctx: *DocumentStore.AnalysisContext, decl: *std
         else => analysis.nodeToString(result.analysis_ctx.tree(), result.decl) orelse return try respondGeneric(id, null_result_response),
     };
 
+    const md_string = try std.fmt.allocPrint(&analysis_ctx.arena.allocator, "```zig\n{}\n```\n```markdown\n{}\n```", .{ signature_str, doc_str });
     try send(types.Response{
         .id = .{ .Integer = id },
         .result = .{
             .Hover = .{
-                .contents = .{ .value = str_value },
+                .contents = .{ .value = md_string },
             },
         },
     });
diff --git a/src/types.zig b/src/types.zig
index 0ed9471..7730dd7 100644
--- a/src/types.zig
+++ b/src/types.zig
@@ -47,14 +47,9 @@ pub const NotificationParams = union(enum) {
     PublishDiagnosticsParams: PublishDiagnosticsParams
 };
 
-pub const MarkedString = struct {
-    language: String = "zig",
-    value: String,
-};
-
 /// Hover response
 pub const Hover = struct {
-    contents: MarkedString,
+    contents: MarkupContent,
 };
 
 /// Params of a response (result)