Fix document symbol with a range based method (outline and breadcumbs) (

#674)

* refactor all hierarchical document symbol

now based on ranges of symbols

* remove pointer in DocumentSymbol.children and useless things

* use sort instead of heap

* fix outline, multiple symbols defined on the same line:

eg:
int i, j, k;

outline before:
k
 j
  i
after:
i
j
k

src/messages/textDocument_document.cc

@@ -6,6 +6,7 @@
 #include "query.hh"
 
 #include <algorithm>
+#include <stack>
 
 MAKE_HASHABLE(ccls::SymbolIdx, t.usr, t.kind);
 
@@ -112,14 +113,10 @@ struct DocumentSymbol {
   SymbolKind kind;
   lsRange range;
   lsRange selectionRange;
-  std::vector<std::unique_ptr<DocumentSymbol>> children;
+  std::vector<DocumentSymbol> children;
 };
-void reflect(JsonWriter &vis, std::unique_ptr<DocumentSymbol> &v);
 REFLECT_STRUCT(DocumentSymbol, name, detail, kind, range, selectionRange,
                children);
-void reflect(JsonWriter &vis, std::unique_ptr<DocumentSymbol> &v) {
-  reflect(vis, *v);
-}
 
 template <typename Def> bool ignore(const Def *def) { return false; }
 template <> bool ignore(const QueryType::Def *def) {
@@ -128,16 +125,6 @@ template <> bool ignore(const QueryType::Def *def) {
 template <> bool ignore(const QueryVar::Def *def) {
   return !def || def->is_local();
 }
-
-void uniquify(std::vector<std::unique_ptr<DocumentSymbol>> &cs) {
-  std::sort(cs.begin(), cs.end(),
-            [](auto &l, auto &r) { return l->range < r->range; });
-  cs.erase(std::unique(cs.begin(), cs.end(),
-                       [](auto &l, auto &r) { return l->range == r->range; }),
-           cs.end());
-  for (auto &c : cs)
-    uniquify(c->children);
-}
 } // namespace
 
 void MessageHandler::textDocument_documentSymbol(JsonReader &reader,
@@ -165,88 +152,70 @@ void MessageHandler::textDocument_documentSymbol(JsonReader &reader,
     std::sort(result.begin(), result.end());
     reply(result);
   } else if (g_config->client.hierarchicalDocumentSymbolSupport) {
-    std::unordered_map<SymbolIdx, std::unique_ptr<DocumentSymbol>> sym2ds;
-    std::vector<std::pair<std::vector<const void *>, DocumentSymbol *>> funcs,
-        types;
+    std::vector<ExtentRef> syms;
+    syms.reserve(file->symbol2refcnt.size());
+
+    /**
+     * with 2 ranges that start at the same Position, we want the wider one
+     * first (swap lhs/rhs)
+     *
+     * we use range for start to start at symbol name
+     * issue with: int i, j, k; otherwise
+     */
+    auto sym_cmp = [](ExtentRef const &lhs, ExtentRef const &rhs) {
+      return lhs.range.start < rhs.range.start ||
+             (lhs.range.start == rhs.range.start &&
+              rhs.extent.end < lhs.extent.end);
+    };
+
     for (auto [sym, refcnt] : file->symbol2refcnt) {
       if (refcnt <= 0 || !sym.extent.valid())
         continue;
-      auto r = sym2ds.try_emplace(SymbolIdx{sym.usr, sym.kind});
-      auto &ds = r.first->second;
-      if (!ds || sym.role & Role::Definition) {
-        if (!ds)
-          ds = std::make_unique<DocumentSymbol>();
-        if (auto range = getLsRange(wf, sym.range)) {
-          ds->selectionRange = *range;
-          ds->range = ds->selectionRange;
-          // For a macro expansion, M(name), we may use `M` for extent and
-          // `name` for spell, do the check as selectionRange must be a subrange
-          // of range.
-          if (sym.extent.valid())
-            if (auto range1 = getLsRange(wf, sym.extent);
-                range1 && range1->includes(*range))
-              ds->range = *range1;
-        }
+      syms.push_back(sym);
+    }
+    std::sort(std::begin(syms), std::end(syms), sym_cmp);
+
+    std::vector<DocumentSymbol> result;
+    std::stack<DocumentSymbol *> indent;
+    for (auto sym : syms) {
+      DocumentSymbol ds;
+      if (auto range = getLsRange(wf, sym.range)) {
+        ds.selectionRange = *range;
+        ds.range = ds.selectionRange;
+        // For a macro expansion, M(name), we may use `M` for extent and
+        // `name` for spell, do the check as selectionRange must be a subrange
+        // of range.
+        if (sym.extent.valid())
+          if (auto range1 = getLsRange(wf, sym.extent);
+              range1 && range1->includes(*range))
+            ds.range = *range1;
       }
-      if (!r.second)
-        continue;
-      std::vector<const void *> def_ptrs;
-      SymbolKind kind = SymbolKind::Unknown;
       withEntity(db, sym, [&](const auto &entity) {
-        auto *def = entity.anyDef();
+        auto const *def = entity.anyDef();
         if (!def)
           return;
-        ds->name = def->name(false);
-        ds->detail = def->detailed_name;
-        for (auto &def : entity.def)
-          if (def.file_id == file_id && !ignore(&def)) {
-            kind = ds->kind = def.kind;
-            def_ptrs.push_back(&def);
+        ds.name = def->name(false);
+        ds.detail = def->detailed_name;
+        ds.kind = def->kind;
+
+        if (!ignore(def) && (ds.kind == SymbolKind::Namespace || allows(sym))) {
+          // drop symbols that are behind the current one
+          while (!indent.empty() &&
+                 // use selectionRange for start to start at symbol name
+                 // issue with: int i, j, k; otherwise
+                 indent.top()->range.end < ds.selectionRange.start) {
+            indent.pop();
           }
+          if (indent.empty()) {
+            result.push_back(std::move(ds));
+            indent.push(&result.back());
+          } else {
+            indent.top()->children.push_back(std::move(ds));
+            indent.push(&indent.top()->children.back());
+          }
+        }
       });
-      if (def_ptrs.empty() || !(kind == SymbolKind::Namespace || allows(sym))) {
-        ds.reset();
-        continue;
-      }
-      if (sym.kind == Kind::Func)
-        funcs.emplace_back(std::move(def_ptrs), ds.get());
-      else if (sym.kind == Kind::Type)
-        types.emplace_back(std::move(def_ptrs), ds.get());
     }
-
-    for (auto &[def_ptrs, ds] : funcs)
-      for (const void *def_ptr : def_ptrs)
-        for (Usr usr1 : ((const QueryFunc::Def *)def_ptr)->vars) {
-          auto it = sym2ds.find(SymbolIdx{usr1, Kind::Var});
-          if (it != sym2ds.end() && it->second)
-            ds->children.push_back(std::move(it->second));
-        }
-    for (auto &[def_ptrs, ds] : types)
-      for (const void *def_ptr : def_ptrs) {
-        auto *def = (const QueryType::Def *)def_ptr;
-        for (Usr usr1 : def->funcs) {
-          auto it = sym2ds.find(SymbolIdx{usr1, Kind::Func});
-          if (it != sym2ds.end() && it->second)
-            ds->children.push_back(std::move(it->second));
-        }
-        for (Usr usr1 : def->types) {
-          auto it = sym2ds.find(SymbolIdx{usr1, Kind::Type});
-          if (it != sym2ds.end() && it->second)
-            ds->children.push_back(std::move(it->second));
-        }
-        for (auto [usr1, _] : def->vars) {
-          auto it = sym2ds.find(SymbolIdx{usr1, Kind::Var});
-          if (it != sym2ds.end() && it->second)
-            ds->children.push_back(std::move(it->second));
-        }
-      }
-    std::vector<std::unique_ptr<DocumentSymbol>> result;
-    for (auto &[_, ds] : sym2ds)
-      if (ds) {
-        uniquify(ds->children);
-        result.push_back(std::move(ds));
-      }
-    uniquify(result);
     reply(result);
   } else {
     std::vector<SymbolInformation> result;