Bug 544980: Added a checker for using directive in header file

Change-Id: Ic77fd2f7504e7a6cc4e15a2fdeb507724db9e74f
Signed-off-by: Marco Stornelli <marco.stornelli@gmail.com>

codan/org.eclipse.cdt.codan.checkers/META-INF/MANIFEST.MF

@@ -2,7 +2,7 @@ Manifest-Version: 1.0
 Bundle-ManifestVersion: 2
 Bundle-Name: %Bundle-Name
 Bundle-SymbolicName: org.eclipse.cdt.codan.checkers;singleton:=true
-Bundle-Version: 3.2.100.qualifier
+Bundle-Version: 3.3.0.qualifier
 Bundle-Activator: org.eclipse.cdt.codan.checkers.CodanCheckersActivator
 Require-Bundle: org.eclipse.core.runtime,
  org.eclipse.core.resources,

codan/org.eclipse.cdt.codan.checkers/OSGI-INF/l10n/bundle.properties

@@ -134,3 +134,8 @@ checker.name.DecltypeAutoChecker = Invalid 'decltype(auto)' specifier checker
 problem.name.DecltypeAutoProblem = Invalid 'decltype(auto)' specifier
 problem.messagePattern.DecltypeAutoProblem = Combining 'decltype(auto)' with other type specifiers is not allowed
 problem.description.DecltypeAutoProblem = This rule will flag 'decltype(auto)' if combined with other type specifiers
+
+checker.name.UsingInHeaderChecker = Using directive in header files checker
+problem.name.UsingInHeaderProblem = Using directive in header
+problem.messagePattern.UsingInHeaderProblem = Using directive in header files can cause name clashes in other files
+problem.description.UsingInHeaderProblem = This rule will flag 'using' directive in header files

codan/org.eclipse.cdt.codan.checkers/plugin.xml

@@ -439,5 +439,20 @@
                name="%problem.name.DecltypeAutoProblem">
          </problem>
       </checker>
+      <checker
+            class="org.eclipse.cdt.codan.internal.checkers.UsingInHeaderChecker"
+            id="org.eclipse.cdt.codan.internal.checkers.UsingInHeaderChecker"
+            name="%checker.name.UsingInHeaderChecker">
+         <problem
+               category="org.eclipse.cdt.codan.core.categories.CodeStyle"
+               defaultEnabled="false"
+               defaultSeverity="Warning"
+               description="%problem.description.UsingInHeaderProblem"
+               id="org.eclipse.cdt.codan.internal.checkers.UsingInHeaderProblem"
+               markerType="org.eclipse.cdt.codan.core.codanProblem"
+               messagePattern="%problem.messagePattern.UsingInHeaderProblem"
+               name="%problem.name.UsingInHeaderProblem">
+         </problem>
+      </checker>
    </extension>
 </plugin>

codan/org.eclipse.cdt.codan.checkers/src/org/eclipse/cdt/codan/internal/checkers/UsingInHeaderChecker.java

@@ -0,0 +1,49 @@
+/*******************************************************************************
+ * Copyright (c) 2019 Marco Stornelli
+ *
+ * This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License 2.0
+ * which accompanies this distribution, and is available at
+ * https://www.eclipse.org/legal/epl-2.0/
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *******************************************************************************/
+package org.eclipse.cdt.codan.internal.checkers;
+
+import org.eclipse.cdt.codan.core.cxx.model.AbstractIndexAstChecker;
+import org.eclipse.cdt.core.dom.ast.ASTVisitor;
+import org.eclipse.cdt.core.dom.ast.IASTDeclaration;
+import org.eclipse.cdt.core.dom.ast.IASTNode;
+import org.eclipse.cdt.core.dom.ast.IASTTranslationUnit;
+import org.eclipse.cdt.core.dom.ast.cpp.ICPPASTNamespaceDefinition;
+import org.eclipse.cdt.core.dom.ast.cpp.ICPPASTTranslationUnit;
+import org.eclipse.cdt.core.dom.ast.cpp.ICPPASTUsingDirective;
+
+public class UsingInHeaderChecker extends AbstractIndexAstChecker {
+	public static final String ERR_ID = "org.eclipse.cdt.codan.internal.checkers.UsingInHeaderProblem"; //$NON-NLS-1$
+
+	@Override
+	public boolean runInEditor() {
+		return true;
+	}
+
+	@Override
+	public void processAst(IASTTranslationUnit ast) {
+		ast.accept(new ASTVisitor() {
+			{
+				shouldVisitDeclarations = true;
+			}
+
+			@Override
+			public int visit(IASTDeclaration specifier) {
+				if (specifier instanceof ICPPASTUsingDirective) {
+					IASTNode parent = specifier.getParent();
+					if ((parent instanceof ICPPASTTranslationUnit || parent instanceof ICPPASTNamespaceDefinition)
+							&& specifier.getTranslationUnit().isHeaderUnit())
+						reportProblem(ERR_ID, specifier);
+				}
+				return PROCESS_CONTINUE;
+			}
+		});
+	}
+}

codan/org.eclipse.cdt.codan.core.tests/src/org/eclipse/cdt/codan/core/internal/checkers/UsingInHeaderCheckerTest.java

@@ -0,0 +1,83 @@
+/*******************************************************************************
+ * Copyright (c) 2019 Marco Stornelli
+ *
+ * This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License 2.0
+ * which accompanies this distribution, and is available at
+ * https://www.eclipse.org/legal/epl-2.0/
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *******************************************************************************/
+package org.eclipse.cdt.codan.core.internal.checkers;
+
+import org.eclipse.cdt.codan.core.tests.CheckerTestCase;
+import org.eclipse.cdt.codan.internal.checkers.UsingInHeaderChecker;
+
+/**
+ * Test for {@link UsingInHeaderChecker} class
+ */
+public class UsingInHeaderCheckerTest extends CheckerTestCase {
+
+	public static final String ERR_ID = UsingInHeaderChecker.ERR_ID;
+
+	@Override
+	public void setUp() throws Exception {
+		super.setUp();
+		enableProblems(ERR_ID);
+	}
+
+	@Override
+	public boolean isCpp() {
+		return true;
+	}
+
+	@Override
+	public boolean isHeader() {
+		return true;
+	}
+
+	//using namespace std;
+	//class Foo {
+	//public:
+	//void bar() {
+	//}
+	//};
+	public void testUsingInGlobalNamespace() throws Exception {
+		loadCodeAndRun(getAboveComment());
+		checkErrorLine(1, ERR_ID);
+	}
+
+	//namespace GLOBAL {
+	//using namespace std;
+	//}
+	//class Foo {
+	//public:
+	//void bar() {
+	//}
+	//};
+	public void testUsingInNamespace() throws Exception {
+		loadCodeAndRun(getAboveComment());
+		checkErrorLine(2, ERR_ID);
+	}
+
+	//class Foo {
+	//public:
+	//void bar() {
+	//}
+	//};
+	public void testWithoutUsing() throws Exception {
+		loadCodeAndRun(getAboveComment());
+		checkNoErrorsOfKind(ERR_ID);
+	}
+
+	//class Foo {
+	//public:
+	//void bar() {
+	//using namespace std;
+	//}
+	//};
+	public void testUsingInFunctionDeclaration() throws Exception {
+		loadCodeAndRun(getAboveComment());
+		checkNoErrorsOfKind(ERR_ID);
+	}
+}

codan/org.eclipse.cdt.codan.core.tests/src/org/eclipse/cdt/codan/core/tests/CodanTestCase.java

@@ -76,6 +76,15 @@ public class CodanTestCase extends BaseTestCase {
 		return false;
 	}
 
+	/**
+	 * Override for header files
+	 *
+	 * @return is header tests
+	 */
+	public boolean isHeader() {
+		return false;
+	}
+
 	@Override
 	public void setUp() throws Exception {
 		super.setUp();
@@ -215,7 +224,18 @@ public class CodanTestCase extends BaseTestCase {
 				return loadcode(code, new File(tmpDir, fileName));
 			}
 		}
-		String ext = cpp ? ".cpp" : ".c";
+		String ext;
+		if (cpp) {
+			if (isHeader())
+				ext = ".hpp";
+			else
+				ext = ".cpp";
+		} else {
+			if (isHeader())
+				ext = ".h";
+			else
+				ext = ".c";
+		}
 		File testFile = null;
 		try {
 			testFile = File.createTempFile("test", ext, tmpDir); //$NON-NLS-1$