Relative paths in import directives.

libsolidity/analysis/NameAndTypeResolver.cpp

@@ -71,19 +71,25 @@ bool NameAndTypeResolver::performImports(SourceUnit& _sourceUnit, map<string, So
 	for (auto const& node: _sourceUnit.nodes())
 		if (auto imp = dynamic_cast<ImportDirective const*>(node.get()))
 		{
-			if (!_sourceUnits.count(imp->identifier()))
+			string const& path = imp->annotation().absolutePath;
+			if (!_sourceUnits.count(path))
 			{
-				reportDeclarationError(node->location(), "Import \"" + imp->identifier() + "\" not found.");
+				reportDeclarationError( node->location(),
+					"Import \"" +
+					path +
+					"\" (referenced as \"" +
+					imp->identifier() +
+					"\") not found."
+				);
 				error = true;
 			}
 			else
 			{
-				auto scope = m_scopes.find(_sourceUnits.at(imp->identifier()));
+				auto scope = m_scopes.find(_sourceUnits.at(path));
 				solAssert(scope != end(m_scopes), "");
 				for (auto const& nameAndDeclaration: scope->second->declarations())
 					for (auto const& declaration: nameAndDeclaration.second)
 						target.registerDeclaration(*declaration, &nameAndDeclaration.first);
-
 			}
 		}
 	return !error;

libsolidity/ast/AST.cpp

@@ -56,6 +56,13 @@ Error ASTNode::createTypeError(string const& _description) const
 	return Error(Error::Type::TypeError) << errinfo_sourceLocation(location()) << errinfo_comment(_description);
 }
 
+ImportAnnotation& ImportDirective::annotation() const
+{
+	if (!m_annotation)
+		m_annotation = new ImportAnnotation();
+	return static_cast<ImportAnnotation&>(*m_annotation);
+}
+
 map<FixedHash<4>, FunctionTypePointer> ContractDefinition::interfaceFunctions() const
 {
 	auto exportedFunctionList = interfaceFunctionList();

libsolidity/ast/AST.h

@@ -142,6 +142,7 @@ public:
 	virtual void accept(ASTConstVisitor& _visitor) const override;
 
 	ASTString const& identifier() const { return *m_identifier; }
+	virtual ImportAnnotation& annotation() const override;
 
 private:
 	ASTPointer<ASTString> m_identifier;

libsolidity/ast/ASTAnnotations.h

@@ -54,6 +54,12 @@ struct DocumentedAnnotation
 	std::multimap<std::string, DocTag> docTags;
 };
 
+struct ImportAnnotation: ASTAnnotation
+{
+	/// The absolute path of the source unit to import.
+	std::string absolutePath;
+};
+
 struct TypeDeclarationAnnotation: ASTAnnotation
 {
 	/// The name of this type, prefixed by proper namespaces if globally accessible.

libsolidity/interface/CompilerStack.cpp

@@ -22,6 +22,7 @@
  */
 
 #include <boost/algorithm/string.hpp>
+#include <boost/filesystem.hpp>
 #include <libsolidity/ast/AST.h>
 #include <libsolidity/parsing/Scanner.h>
 #include <libsolidity/parsing/Parser.h>
@@ -367,7 +368,7 @@ void CompilerStack::resolveImports()
 	vector<Source const*> sourceOrder;
 	set<Source const*> sourcesSeen;
 
-	function<void(Source const*)> toposort = [&](Source const* _source)
+	function<void(string const&, Source const*)> toposort = [&](string const& _sourceName, Source const* _source)
 	{
 		if (sourcesSeen.count(_source))
 			return;
@@ -375,26 +376,44 @@ void CompilerStack::resolveImports()
 		for (ASTPointer<ASTNode> const& node: _source->ast->nodes())
 			if (ImportDirective const* import = dynamic_cast<ImportDirective*>(node.get()))
 			{
-				string const& id = import->identifier();
-				if (!m_sources.count(id))
+				string path = absolutePath(import->identifier(), _sourceName);
+				import->annotation().absolutePath = path;
+				if (!m_sources.count(path))
 					BOOST_THROW_EXCEPTION(
 						Error(Error::Type::ParserError)
 							<< errinfo_sourceLocation(import->location())
 							<< errinfo_comment("Source not found.")
 					);
 
-				toposort(&m_sources[id]);
+				toposort(path, &m_sources[path]);
 			}
 		sourceOrder.push_back(_source);
 	};
 
 	for (auto const& sourcePair: m_sources)
 		if (!sourcePair.second.isLibrary)
-			toposort(&sourcePair.second);
+			toposort(sourcePair.first, &sourcePair.second);
 
 	swap(m_sourceOrder, sourceOrder);
 }
 
+string CompilerStack::absolutePath(string const& _path, string const& _reference) const
+{
+	// Anything that does not start with `.` is an absolute path.
+	if (_path.empty() || _path.front() != '.')
+		return _path;
+	using path = boost::filesystem::path;
+	path p(_path);
+	path result(_reference);
+	result.remove_filename();
+	for (path::iterator it = p.begin(); it != p.end(); ++it)
+		if (*it == "..")
+			result = result.parent_path();
+		else if (*it != ".")
+			result /= *it;
+	return result.string();
+}
+
 void CompilerStack::compileContract(
 	bool _optimize,
 	unsigned _runs,

libsolidity/interface/CompilerStack.h

@@ -199,6 +199,8 @@ private:
 	};
 
 	void resolveImports();
+	/// @returns the absolute path corresponding to @a _path relative to @a _reference.
+	std::string absolutePath(std::string const& _path, std::string const& _reference) const;
 	/// Compile a single contract and put the result in @a _compiledContracts.
 	void compileContract(
 		bool _optimize,

test/libsolidity/Imports.cpp

@@ -76,6 +76,23 @@ BOOST_AUTO_TEST_CASE(circular_import)
 	BOOST_CHECK(c.compile());
 }
 
+BOOST_AUTO_TEST_CASE(relative_import)
+{
+	CompilerStack c;
+	c.addSource("a", "import \"./dir/b\"; contract A is B {}");
+	c.addSource("dir/b", "contract B {}");
+	c.addSource("dir/c", "import \"../a\"; contract C is A {}");
+	BOOST_CHECK(c.compile());
+}
+
+BOOST_AUTO_TEST_CASE(relative_import_multiplex)
+{
+	CompilerStack c;
+	c.addSource("a", "contract A {}");
+	c.addSource("dir/a/b/c", "import \"../../.././a\"; contract B is A {}");
+	BOOST_CHECK(c.compile());
+}
+
 BOOST_AUTO_TEST_SUITE_END()
 
 }