From fc89a65ce70f9ee3f12d09b2709281158374656b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Patrick=20L=C3=BChne?= <patrick-github@luehne.de>
Date: Thu, 24 Nov 2016 16:04:53 +0100
Subject: [PATCH] Improved output of negated literals and added unit test.

---
 include/anthem/Body.h     | 10 ++++------
 include/anthem/Head.h     |  4 ++--
 tests/TestTranslation.cpp |  8 ++++++++
 3 files changed, 14 insertions(+), 8 deletions(-)

diff --git a/include/anthem/Body.h b/include/anthem/Body.h
index 37b2648..b0e61d1 100644
--- a/include/anthem/Body.h
+++ b/include/anthem/Body.h
@@ -87,12 +87,10 @@ struct TermPrintVisitor
 				<< argument;
 		}
 
-		outputStream << " " << Clingo::AST::BinaryOperator::And << " ";
-
-		if (literal.sign == Clingo::AST::Sign::Negation)
-			outputStream << Clingo::AST::Sign::Negation << " ";
-
-		outputStream << output::Function(function.name) << "(";
+		outputStream
+			<< " " << Clingo::AST::BinaryOperator::And << " "
+			<< literal.sign
+			<< output::Function(function.name) << "(";
 
 		for (auto i = function.arguments.cbegin(); i != function.arguments.cend(); i++)
 		{
diff --git a/include/anthem/Head.h b/include/anthem/Head.h
index e713b4a..89c296b 100644
--- a/include/anthem/Head.h
+++ b/include/anthem/Head.h
@@ -222,8 +222,8 @@ struct HeadLiteralPrintSubstitutedVisitor
 	{
 		if (literal.sign == Clingo::AST::Sign::DoubleNegation)
 			throwErrorAtLocation(literal.location, "double-negated literals currently unsupported", context);
-		else if (literal.sign == Clingo::AST::Sign::Negation)
-			context.logger.outputStream() << Clingo::AST::Sign::Negation << " ";
+
+		context.logger.outputStream() << literal.sign;
 
 		literal.data.accept(LiteralPrintSubstitutedVisitor(), literal, context);
 	}
diff --git a/tests/TestTranslation.cpp b/tests/TestTranslation.cpp
index 66800d4..6dc7267 100644
--- a/tests/TestTranslation.cpp
+++ b/tests/TestTranslation.cpp
@@ -120,4 +120,12 @@ TEST_CASE("[translation] Rules are translated correctly", "[translation]")
 
 		REQUIRE(output.str() == "V1 in X and V2 in (1,) and exists X1, X2 (X1 in X and X2 in (2,) and q(X1, X2)) -> p(V1, V2)\n");
 	}
+
+	SECTION("single negation")
+	{
+		input << "not p(X, 1) :- not q(X, 2).";
+		anthem::translate("input", input, context);
+
+		REQUIRE(output.str() == "V1 in X and V2 in 1 and exists X1, X2 (X1 in X and X2 in 2 and not q(X1, X2)) -> not p(V1, V2)\n");
+	}
 }