NatSpec: Implement default inheritance.

libsolidity/analysis/DocStringAnalyser.cpp

@@ -32,6 +32,33 @@ using namespace solidity;
 using namespace solidity::langutil;
 using namespace solidity::frontend;
 
+namespace
+{
+
+void copyMissingTags(StructurallyDocumentedAnnotation& _target, set<CallableDeclaration const*> const& _baseFunctions)
+{
+	if (_baseFunctions.size() != 1)
+		return;
+
+	auto& sourceDoc = dynamic_cast<StructurallyDocumentedAnnotation const&>((*_baseFunctions.begin())->annotation());
+
+	set<string> existingTags;
+
+	for (auto const& iterator: _target.docTags)
+		existingTags.insert(iterator.first);
+
+	for (auto const& [tag, content]: sourceDoc.docTags)
+		if (tag != "inheritdoc" && !existingTags.count(tag))
+			_target.docTags.emplace(tag, content);
+}
+
+bool parameterNamesEqual(CallableDeclaration const& _a, CallableDeclaration const& _b)
+{
+	return boost::range::equal(_a.parameters(), _b.parameters(), [](auto const& pa, auto const& pb) { return pa->name() == pb->name(); });
+}
+
+}
+
 bool DocStringAnalyser::analyseDocStrings(SourceUnit const& _sourceUnit)
 {
 	auto errorWatcher = m_errorReporter.errorWatcher();
@@ -79,6 +106,9 @@ bool DocStringAnalyser::visit(VariableDeclaration const& _variable)
 				"Documentation tag @title and @author is only allowed on contract definitions. "
 				"It will be disallowed in 0.7.0."
 			);
+
+		if (_variable.annotation().docTags.empty())
+			copyMissingTags(_variable.annotation(), _variable.annotation().baseFunctions);
 	}
 	return false;
 }
@@ -143,6 +173,13 @@ void DocStringAnalyser::handleCallable(
 	parseDocStrings(_node, _annotation, validTags, "functions");
 	checkParameters(_callable, _node, _annotation);
 
+	if (
+		_annotation.docTags.empty() &&
+		_callable.annotation().baseFunctions.size() == 1 &&
+		parameterNamesEqual(_callable, **_callable.annotation().baseFunctions.begin())
+	)
+		copyMissingTags(_annotation, _callable.annotation().baseFunctions);
+
 	if (_node.documentation() && _annotation.docTags.count("author") > 0)
 		m_errorReporter.warning(
 			9843_error, _node.documentation()->location(),

libsolidity/interface/CompilerStack.cpp

@@ -307,11 +307,6 @@ bool CompilerStack::analyze()
 			if (source->ast && !syntaxChecker.checkSyntax(*source->ast))
 				noErrors = false;
 
-		DocStringAnalyser docStringAnalyser(m_errorReporter);
-		for (Source const* source: m_sourceOrder)
-			if (source->ast && !docStringAnalyser.analyseDocStrings(*source->ast))
-				noErrors = false;
-
 		m_globalContext = make_shared<GlobalContext>();
 		// We need to keep the same resolver during the whole process.
 		NameAndTypeResolver resolver(*m_globalContext, m_evmVersion, m_errorReporter);
@@ -367,6 +362,11 @@ bool CompilerStack::analyze()
 						if (!contractLevelChecker.check(*contract))
 							noErrors = false;
 
+		DocStringAnalyser docStringAnalyser(m_errorReporter);
+		for (Source const* source: m_sourceOrder)
+			if (source->ast && !docStringAnalyser.analyseDocStrings(*source->ast))
+				noErrors = false;
+
 		// New we run full type checks that go down to the expression level. This
 		// cannot be done earlier, because we need cross-contract types and information
 		// about whether a contract is abstract for the `new` expression.