allow implementation symbols to remain if they have their own docs

Author: QuietMisdreavus

lib/SymbolGraphGen/SymbolGraph.cpp

@@ -12,6 +12,7 @@
 
 #include "clang/AST/DeclObjC.h"
 #include "swift/AST/ASTContext.h"
+#include "swift/AST/Comment.h"
 #include "swift/AST/Decl.h"
 #include "swift/AST/Module.h"
 #include "swift/AST/ProtocolConformance.h"
@@ -190,7 +191,12 @@ SymbolGraph::isRequirementOrDefaultImplementation(const ValueDecl *VD) const {
 
 void SymbolGraph::recordNode(Symbol S) {
   if (Walker.Options.SkipProtocolImplementations && S.getInheritedDecl()) {
-    return;
+    const auto *DocCommentProvidingDecl =
+      getDocCommentProvidingDecl(S.getLocalSymbolDecl(), /*AllowSerialized=*/true);
+
+    // allow implementation symbols to remain if they have their own comment
+    if (DocCommentProvidingDecl != S.getLocalSymbolDecl())
+      return;
   }
 
   Nodes.insert(S);

test/SymbolGraph/Symbols/SkipProtocolImplementations.swift

@@ -1,20 +1,36 @@
 // RUN: %empty-directory(%t)
-// RUN: %target-build-swift %s -module-name SkipProtocolImplementations -emit-module -emit-module-path %t/
+// RUN: %target-swift-frontend %s -module-name SkipProtocolImplementations -emit-module -emit-module-path %t/SkipProtocolImplementations.swiftmodule -emit-symbol-graph -emit-symbol-graph-dir %t/ -skip-protocol-implementations
+// RUN: %{python} -m json.tool %t/SkipProtocolImplementations.symbols.json %t/SkipProtocolImplementations.formatted.symbols.json
+// RUN: %FileCheck %s --input-file %t/SkipProtocolImplementations.formatted.symbols.json
+
+// RUN: %empty-directory(%t)
+// RUN: %target-swift-frontend %s -module-name SkipProtocolImplementations -emit-module -emit-module-path %t/SkipProtocolImplementations.swiftmodule -emit-module-doc-path %t/SkipProtocolImplementations.swiftdoc
 // RUN: %target-swift-symbolgraph-extract -module-name SkipProtocolImplementations -I %t -skip-protocol-implementations -pretty-print -output-dir %t
 // RUN: %FileCheck %s --input-file %t/SkipProtocolImplementations.symbols.json
 
 // make sure that using `-skip-protocol-implementations` removes the functions from `SomeProtocol` on `SomeStruct`
 // CHECK-NOT: s:27SkipProtocolImplementations04SomeB0PAAE9bonusFuncyyF::SYNTHESIZED::s:27SkipProtocolImplementations10SomeStructV
 // CHECK-NOT: s:27SkipProtocolImplementations10SomeStructV8someFuncyyF
 
-// the `-skip-protocol-implementations` code should drop any symbol that would get source-origin information
-// CHECK-NOT: sourceOrigin
+// CHECK-LABEL: "symbols": [
+
+// SomeStruct.otherFunc() should be present because it has its own doc comment
+// CHECK: s:27SkipProtocolImplementations10SomeStructV9otherFuncyyF
+
+// CHECK-LABEL: "relationships": [
 
-// however, we want to make sure that the conformance relationship itself stays
-// CHECK: conformsTo
+// we want to make sure that the conformance relationship itself stays
+// CHECK-DAG: conformsTo
+
+// SomeStruct.otherFunc() should be the only one with sourceOrigin information
+// CHECK-COUNT-1: sourceOrigin
 
 public protocol SomeProtocol {
+    /// Base docs
     func someFunc()
+
+    /// Base docs
+    func otherFunc()
 }
 
 public extension SomeProtocol {
@@ -23,4 +39,7 @@ public extension SomeProtocol {
 
 public struct SomeStruct: SomeProtocol {
     public func someFunc() {}
+
+    /// Local docs
+    public func otherFunc() {}
 }