Show unimplemented function if trying to instantiate an abstract class

4 files changed, 25 insertions, 1 deletions

diff --git a/Changelog.md b/Changelog.md
index 86cf1058..a96485f9 100644
--- a/Changelog.md
+++ b/Changelog.md
@@ -1,6 +1,7 @@
 ### 0.4.15 (unreleased)
 
 Features:
+ * Type Checker: Show unimplemented function if trying to instantiate an abstract class.
 
 Bugfixes:
  * Code Generator: ``.delegatecall()`` should always return execution outcome.
diff --git a/libsolidity/analysis/TypeChecker.cpp b/libsolidity/analysis/TypeChecker.cpp
index fab410eb..cc2f95ef 100644
--- a/libsolidity/analysis/TypeChecker.cpp
+++ b/libsolidity/analysis/TypeChecker.cpp
@@ -1523,7 +1523,14 @@ void TypeChecker::endVisit(NewExpression const& _newExpression)
 		if (!contract)
 			m_errorReporter.fatalTypeError(_newExpression.location(), "Identifier is not a contract.");
 		if (!contract->annotation().unimplementedFunctions.empty())
-			m_errorReporter.typeError(_newExpression.location(), "Trying to create an instance of an abstract contract.");
+			m_errorReporter.typeError(
+				_newExpression.location(),
+				SecondarySourceLocation().append(
+					"Missing implementation:",
+					contract->annotation().unimplementedFunctions.front()->location()
+				),
+				"Trying to create an instance of an abstract contract."
+			);
 		if (!contract->constructorIsPublic())
 			m_errorReporter.typeError(_newExpression.location(), "Contract with internal constructor cannot be created directly.");
 
diff --git a/libsolidity/interface/ErrorReporter.cpp b/libsolidity/interface/ErrorReporter.cpp
index f9ef4ceb..e6171756 100644
--- a/libsolidity/interface/ErrorReporter.cpp
+++ b/libsolidity/interface/ErrorReporter.cpp
@@ -151,6 +151,16 @@ void ErrorReporter::syntaxError(SourceLocation const& _location, string const& _
 	);
 }
 
+void ErrorReporter::typeError(SourceLocation const& _location, SecondarySourceLocation const& _secondaryLocation, string const& _description)
+{
+	error(
+		Error::Type::TypeError,
+		_location,
+		_secondaryLocation,
+		_description
+	);
+}
+
 void ErrorReporter::typeError(SourceLocation const& _location, string const& _description)
 {
 	error(
diff --git a/libsolidity/interface/ErrorReporter.h b/libsolidity/interface/ErrorReporter.h
index 8b066a3e..42b0c8b6 100644
--- a/libsolidity/interface/ErrorReporter.h
+++ b/libsolidity/interface/ErrorReporter.h
@@ -73,6 +73,12 @@ public:
 
 	void syntaxError(SourceLocation const& _location, std::string const& _description);
 
+	void typeError(
+		SourceLocation const& _location,
+		SecondarySourceLocation const& _secondaryLocation,
+		std::string const& _description
+	);
+
 	void typeError(SourceLocation const& _location, std::string const& _description);
 
 	void fatalTypeError(SourceLocation const& _location, std::string const& _description);