Records store friends as relationships

include/mrdocs/Metadata/Info/Enum.hpp

@@ -17,7 +17,6 @@
 #include <mrdocs/Metadata/Source.hpp>
 #include <mrdocs/Metadata/Type.hpp>
 #include <mrdocs/Dom/LazyArray.hpp>
-#include <ranges>
 
 namespace clang::mrdocs {
 

include/mrdocs/Metadata/Info/Friend.hpp

@@ -18,24 +18,20 @@
 namespace clang::mrdocs {
 
 /** Info for friend declarations.
+
+    - Friendship is not transitive
+    - Friendship is not inherited
+    - Access specifiers have no effect on the meaning of friend declarations
 */
 struct FriendInfo final
-    : InfoCommonBase<InfoKind::Friend>
 {
     /** Befriended symbol.
     */
-    SymbolID FriendSymbol = SymbolID::invalid;
+    SymbolID id = SymbolID::invalid;
 
     /** Befriended type.
     */
-    Polymorphic<TypeInfo> FriendType;
-
-    //--------------------------------------------
-
-    explicit FriendInfo(SymbolID ID) noexcept
-        : InfoCommonBase(ID)
-    {
-    }
+    Polymorphic<TypeInfo> Type;
 };
 
 MRDOCS_DECL
@@ -52,20 +48,19 @@ tag_invoke(
     FriendInfo const& I,
     DomCorpus const* domCorpus)
 {
-    tag_invoke(t, io, dynamic_cast<Info const&>(I), domCorpus);
-    if (I.FriendSymbol)
+    if (I.id)
     {
         io.defer("name", [&I, domCorpus]{
-            return dom::ValueFrom(I.FriendSymbol, domCorpus).get("name");
+            return dom::ValueFrom(I.id, domCorpus).get("name");
         });
-        io.map("symbol", I.FriendSymbol);
+        io.map("symbol", I.id);
     }
-    else if (I.FriendType)
+    else if (I.Type)
     {
         io.defer("name", [&]{
-            return dom::ValueFrom(I.FriendType, domCorpus).get("name");
+            return dom::ValueFrom(I.Type, domCorpus).get("name");
         });
-        io.map("type", I.FriendType);
+        io.map("type", I.Type);
     }
 }
 

include/mrdocs/Metadata/Info/InfoNodes.inc

@@ -20,7 +20,6 @@ INFO(Enum)
 INFO(EnumConstant)
 INFO(Typedef)
 INFO(Variable)
-INFO(Friend)
 INFO(Guide)
 INFO(NamespaceAlias)
 INFO(Using)

include/mrdocs/Metadata/Info/Record.hpp

@@ -16,6 +16,7 @@
 #include <mrdocs/Metadata/Info.hpp>
 #include <mrdocs/Metadata/Source.hpp>
 #include <mrdocs/Metadata/Template.hpp>
+#include <mrdocs/Metadata/Info/Friend.hpp>
 #include <mrdocs/Dom.hpp>
 #include <mrdocs/Dom/LazyObject.hpp>
 #include <mrdocs/Dom/LazyArray.hpp>
@@ -46,7 +47,6 @@ struct RecordTranche
     std::vector<SymbolID> StaticVariables;
     std::vector<SymbolID> Concepts;
     std::vector<SymbolID> Guides;
-    std::vector<SymbolID> Friends;
     std::vector<SymbolID> Usings;
 };
 
@@ -60,7 +60,7 @@ allMembers(RecordTranche const& T)
 {
     // This is a trick to emulate views::concat in C++20
     return std::views::transform(
-        std::views::iota(0, 12),
+        std::views::iota(0, 11),
         [&T](int const i) -> auto const&
         {
             switch (i) {
@@ -74,8 +74,7 @@ allMembers(RecordTranche const& T)
                 case 7: return T.StaticVariables;
                 case 8: return T.Concepts;
                 case 9: return T.Guides;
-                case 10: return T.Friends;
-                case 11: return T.Usings;
+                case 10: return T.Usings;
                 default: throw std::out_of_range("Invalid index");
             }
         }
@@ -102,7 +101,6 @@ tag_invoke(
     io.map("staticVariables", dom::LazyArray(I.StaticVariables, domCorpus));
     io.map("concepts", dom::LazyArray(I.Concepts, domCorpus));
     io.map("guides", dom::LazyArray(I.Guides, domCorpus));
-    io.map("friends", dom::LazyArray(I.Friends, domCorpus));
     io.map("usings", dom::LazyArray(I.Usings, domCorpus));
 }
 
@@ -295,8 +293,14 @@ struct RecordInfo final
      */
     std::vector<SymbolID> Derived;
 
+    /** Lists of members.
+     */
     RecordInterface Interface;
 
+    /** List of friends.
+    */
+    std::vector<FriendInfo> Friends;
+
     //--------------------------------------------
 
     explicit RecordInfo(SymbolID const& ID) noexcept
@@ -354,6 +358,7 @@ tag_invoke(
     io.map("derived", dom::LazyArray(I.Derived, domCorpus));
     io.map("interface", I.Interface);
     io.map("template", I.Template);
+    io.map("friends", dom::LazyArray(I.Friends, domCorpus));
 }
 
 /** Map the RecordInfo to a @ref dom::Value object.

mrdocs.rnc

@@ -187,10 +187,7 @@ grammar
     Friend =
         element friend
         {
-            Access ?,
             ID,
-            Location *,
-            Javadoc ?,
             (
                 element befriended
                 {

share/mrdocs/addons/generator/adoc/partials/symbol.adoc.hbs

@@ -31,7 +31,7 @@
 {{! Base classes }}
 {{#if (any_of_by symbol.bases "isPublic")}}
 {{#> markup/dynamic-level-h }}Base Classes{{/markup/dynamic-level-h}}
-[,cols=2]
+[cols=2]
 |===
 | Name
 | Description
@@ -58,7 +58,7 @@
 {{#if symbol.constants}}
 {{#> markup/dynamic-level-h }}Members{{/markup/dynamic-level-h}}
 
-[,cols=2]
+[cols=2]
 |===
 | Name
 | Description
@@ -73,6 +73,25 @@
 |===
 
 {{/if}}
+{{/if}}
+{{! Friends }}
+{{#if symbol.friends}}
+{{#> markup/dynamic-level-h }}Friends{{/markup/dynamic-level-h}}
+[cols=2]
+|===
+| Name
+| Description
+{{#each symbol.friends }}
+{{#if symbol}}
+| {{#>markup/code}}{{> symbol/name symbol link=symbol }}{{/markup/code}}
+| {{> javadoc/inline-brief symbol.doc.brief }}
+{{else}}
+| {{#>markup/code}}{{> type/declarator type }}{{/markup/code}}
+|
+{{/if}}
+{{/each}}
+|===
+
 {{/if}}
 {{! Using directives }}
 {{#if symbol.usingDirectives}}
@@ -82,7 +101,7 @@
 {{! Related symbols }}
 {{#if symbol.doc.related}}
 {{#> markup/dynamic-level-h }}Non-Member Functions{{/markup/dynamic-level-h}}
-[,cols=2]
+[cols=2]
 |===
 | Name
 | Description
@@ -96,7 +115,7 @@
 {{! Derived classes }}
 {{#if symbol.derived}}
 {{#> markup/dynamic-level-h }}Derived Classes{{/markup/dynamic-level-h}}
-[,cols=2]
+[cols=2]
 |===
 | Name
 | Description

share/mrdocs/addons/generator/common/partials/symbol/tranche.hbs

@@ -31,7 +31,6 @@
 {{>symbol/members-table members=tranche.staticFunctions title=(concat (select label (concat label " ") "") "Static Member Functions")}}
 {{>symbol/members-table members=tranche.variables title=(concat (select label (concat label " ") "") "Data Members")}}
 {{>symbol/members-table members=tranche.staticVariables title=(concat (select label (concat label " ") "") "Static Data Members")}}
-{{>symbol/members-table members=tranche.friends title=(concat (select label (concat label " ") "") "Friends")}}
 {{>symbol/members-table members=tranche.aliases title=(concat (select label (concat label " ") "") "Aliases")}}
 {{>symbol/members-table members=tranche.usings title=(concat (select label (concat label " ") "") "Using Declarations")}}
 {{/if}}

share/mrdocs/addons/generator/html/partials/symbol.html.hbs

@@ -98,6 +98,34 @@
 </table>
 </div>
 {{/if}}
+{{! Friends }}
+{{#if symbol.friends}}
+<div>
+{{#> markup/dynamic-level-h }}Friends{{/markup/dynamic-level-h}}
+<table>
+<thead>
+<tr>
+<th>Name</th>
+<th>Description</th>
+</tr>
+</thead>
+<tbody>
+{{#each symbol.friends }}
+<tr>
+{{#if symbol}}
+<td>{{#>markup/code}}{{> symbol/name symbol link=symbol }}{{/markup/code}}</td>
+<td>{{> javadoc/inline-brief symbol.doc.brief }}</td>
+{{else}}
+<td>{{#>markup/code}}{{> type/declarator type }}{{/markup/code}}</td>
+<td></td>
+{{/if}}
+</tr>
+{{/each}}
+|===
+</tbody>
+</table>
+</div>
+{{/if}}
 {{! Using directives }}
 {{#if symbol.usingDirectives}}
 <div>

src/lib/AST/ASTVisitor.cpp

@@ -713,6 +713,26 @@ populate(
                 B.isVirtual());
         }
     }
+
+    // Iterate over the friends of the class
+    if (D->hasDefinition() && D->hasFriends())
+    {
+        for (FriendDecl const* FD : D->friends())
+        {
+            // Check if the friend is a fundamental type
+            // Declaring a fundamental type like `int` as a friend of a
+            // class or struct does not have any practical effect. Thus,
+            // it's not considered part of the public API.
+            if (TypeSourceInfo const* TSI = FD->getFriendType())
+            {
+                Type const* T = TSI->getType().getTypePtrOrNull();
+                MRDOCS_CHECK_OR_CONTINUE(!T || !T->isBuiltinType());
+            }
+            FriendInfo F;
+            populate(F, FD);
+            I.Friends.push_back(std::move(F));
+        }
+    }
 }
 
 void
@@ -1113,32 +1133,31 @@ populate(
     FriendInfo& I,
     FriendDecl const* D)
 {
-    // A NamedDecl nominated by a FriendDecl
-    // will be one of the following:
-    // - FunctionDecl
-    // - FunctionTemplateDecl
-    // - ClassTemplateDecl
-    if (NamedDecl* ND = D->getFriendDecl())
+    if (TypeSourceInfo const* TSI = D->getFriendType())
     {
-        generateID(ND, I.FriendSymbol);
-        // If this is a friend function declaration naming
-        // a previously undeclared function, traverse it.
-        // in addition to this, traverse the declaration if
-        // it's a class templates first declared as a friend
-        if((ND->isFunctionOrFunctionTemplate() &&
-            ND->getFriendObjectKind() == Decl::FOK_Undeclared) ||
-            (isa<ClassTemplateDecl>(ND) && ND->isFirstDecl()))
-        {
-            traverse(cast<Decl>(ND));
-        }
+        I.Type = toTypeInfo(TSI->getType());
+        MRDOCS_CHECK_OR(I.Type->isNamed());
+        auto const& NTI = dynamic_cast<NamedTypeInfo&>(*I.Type);
+        MRDOCS_CHECK_OR(NTI.Name);
+        I.id = NTI.Name->id;
     }
-    // Since a friend declaration which name non-class types
-    // will be ignored, a type nominated by a FriendDecl can
-    // essentially be anything
-    if (TypeSourceInfo const* TSI = D->getFriendType())
+    else if (NamedDecl const* ND = D->getFriendDecl())
     {
-        I.FriendType = toTypeInfo(TSI->getType());
+        // ND can be a function or a class
+        ScopeExitRestore s(mode_, Dependency);
+        if (Info const* SI = traverse(dyn_cast<Decl>(ND)))
+        {
+            I.id = SI->id;
+        }
     }
+    // The newly traversed info might need to inherit the
+    // documentation from the FriendDecl when the friend
+    // is the only declaration.
+    MRDOCS_CHECK_OR(isDocumented(D));
+    Info* TI = find(I.id);
+    MRDOCS_CHECK_OR(TI);
+    MRDOCS_CHECK_OR(!TI->javadoc);
+    populate(TI->javadoc, D);
 }
 
 void
@@ -1779,11 +1798,6 @@ addMember(RecordTranche& T, Info const& Member)
         addMember(T.Guides, *U);
         return;
     }
-    if (auto const* U = Member.asFriendPtr())
-    {
-        addMember(T.Friends, *U);
-        return;
-    }
     if (auto const* U = Member.asUsingPtr())
     {
         addMember(T.Usings, *U);

src/lib/AST/ASTVisitor.hpp

@@ -252,6 +252,10 @@ class ASTVisitor
      */
     TraversalMode mode_ = Regular;
 
+    /* A map which stores the Info types created by each decl.
+     */
+    std::unordered_map<FriendDecl const*, Info const*> friendDecls_;
+
 public:
     /** Constructor for ASTVisitor.
 

src/lib/AST/ClangHelpers.hpp

@@ -169,11 +169,6 @@ template <>
 struct InfoTypeFor<FieldDecl>
     : std::type_identity<VariableInfo> {};
 
-// Extract FriendInfo from FriendDecl
-template <>
-struct InfoTypeFor<FriendDecl>
-    : std::type_identity<FriendInfo> {};
-
 // Extract GuideInfo from CXXDeductionGuideDecl
 template <>
 struct InfoTypeFor<CXXDeductionGuideDecl>