Bug 412463 - Code completion stops working in the presence of predefined

macro

Change-Id: Iabeb0742ce5564a150f859185c0f8eb64805955a
Signed-off-by: Nathan Ridge <zeratul976@hotmail.com>
Reviewed-on: https://git.eclipse.org/r/14399
Reviewed-by: Sergey Prigogin <eclipse.sprigogin@gmail.com>
IP-Clean: Sergey Prigogin <eclipse.sprigogin@gmail.com>
Tested-by: Sergey Prigogin <eclipse.sprigogin@gmail.com>

core/org.eclipse.cdt.core/model/org/eclipse/cdt/internal/core/model/TranslationUnit.java

@@ -915,7 +915,7 @@ public class TranslationUnit extends Openable implements ITranslationUnit {
 						for (IIndexFile indexFile : index.getFiles(linkageID, ifl)) {
 							int score= indexFile.getMacros().length * 2;
 							IIndexFile context= getParsedInContext(indexFile);
-							if (isSourceFile(context))
+							if (isSourceFile(context, getCProject().getProject()))
 								score++;
 							if (score > bestScore) {
 								bestScore= score;
@@ -936,7 +936,7 @@ public class TranslationUnit extends Openable implements ITranslationUnit {
 		return null;
 	}
 
-	private IIndexFile getParsedInContext(IIndexFile indexFile) throws CoreException {
+	public static IIndexFile getParsedInContext(IIndexFile indexFile) throws CoreException {
 		HashSet<IIndexFile> visited= new HashSet<IIndexFile>();
 		// Bug 199412, may recurse.
 		while (visited.add(indexFile)) {
@@ -949,12 +949,12 @@ public class TranslationUnit extends Openable implements ITranslationUnit {
 	}
 
 	/**
-	 * Returns <code>true</code> if the given file was parsed in a context of a source file.
+	 * Returns <code>true</code> if the given file is a source file.
 	 * @throws CoreException
 	 */
-	private boolean isSourceFile(IIndexFile indexFile) throws CoreException {
+	public static boolean isSourceFile(IIndexFile indexFile, IProject project) throws CoreException {
 		String path = indexFile.getLocation().getURI().getPath();
-		IContentType cType = CCorePlugin.getContentType(getCProject().getProject(), path);
+		IContentType cType = CCorePlugin.getContentType(project, path);
 		if (cType == null)
 			return false;
 

core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/index/IIndexFragment.java

@@ -132,9 +132,6 @@ public interface IIndexFragment {
 	 * for different sets of macro definitions.
 	 * This method may only return files that are actually managed by this fragment.
 	 * This method returns files without content, also.
-	 * <p>
-	 * When a header file is stored in the index in multiple variants for different sets of macro
-	 * definitions, this method will return an arbitrary one of these variants.
 	 *
 	 * @param linkageID the id of the linkage in which the file has been parsed.
 	 * @param location the IIndexFileLocation representing the location of the file

core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/pdom/WritablePDOM.java

@@ -23,14 +23,17 @@ import org.eclipse.cdt.core.dom.ast.IASTNode;
 import org.eclipse.cdt.core.dom.ast.IASTPreprocessorIncludeStatement;
 import org.eclipse.cdt.core.dom.ast.IASTPreprocessorStatement;
 import org.eclipse.cdt.core.dom.ast.IASTTranslationUnit;
+import org.eclipse.cdt.core.index.IIndexFile;
 import org.eclipse.cdt.core.index.IIndexFileLocation;
 import org.eclipse.cdt.core.index.IIndexLocationConverter;
+import org.eclipse.cdt.core.model.ITranslationUnit;
 import org.eclipse.cdt.core.parser.ISignificantMacros;
 import org.eclipse.cdt.internal.core.index.FileContentKey;
 import org.eclipse.cdt.internal.core.index.IIndexFragment;
 import org.eclipse.cdt.internal.core.index.IIndexFragmentFile;
 import org.eclipse.cdt.internal.core.index.IWritableIndex.IncludeInformation;
 import org.eclipse.cdt.internal.core.index.IWritableIndexFragment;
+import org.eclipse.cdt.internal.core.model.TranslationUnit;
 import org.eclipse.cdt.internal.core.pdom.db.ChunkCache;
 import org.eclipse.cdt.internal.core.pdom.db.DBProperties;
 import org.eclipse.cdt.internal.core.pdom.db.IBTreeVisitor;
@@ -256,6 +259,41 @@ public class WritablePDOM extends PDOM implements IWritableIndexFragment {
 		return false;
 	}
 
+	/**
+	 * Returns the best file for the given location, linkage, and translation unit.
+	 * May return <code>null</code>, if no such file exists.
+	 *
+	 * The "best" file (variant) is the one with the most content, as measured
+	 * by the total number of macros defined in the file. The rationale is that
+	 * often one of the variants will contain most of the code and the others
+	 * just small pieces, and we are usually interested in the one with most of
+	 * the code. As a tiebreaker, a variant that was parsed in the context of a
+	 * source file is preferred, since a header parsed outside of the context of
+	 * a code file may not represent code that a compiler actually sees.
+	 *
+	 * @param linkageID the id of the linkage in which the file has been parsed.
+	 * @param location the IIndexFileLocation representing the location of the file
+	 * @param tu the translation unit from which 'location' originates
+	 * @return the best file for the location, or <code>null</code> if the file is not
+	 *     present in the index
+	 * @throws CoreException
+	 */
+	private PDOMFile getBestFile(int linkageID, IIndexFileLocation location, ITranslationUnit tu) throws CoreException {
+		IIndexFile[] files = getFiles(linkageID, location);
+		IIndexFile best = null;
+		int bestScore = -1;
+		for (IIndexFile file : files) {
+			int score = file.getMacros().length * 2;
+			if (TranslationUnit.isSourceFile(TranslationUnit.getParsedInContext(file), tu.getCProject().getProject()))
+				score++;
+			if (score > bestScore) {
+				bestScore = score;
+				best = file;
+			}
+		}
+		return (PDOMFile) best;
+	}
+
 	public PDOMFile getFileForASTNode(int linkageID, IASTNode node) throws CoreException {
 		if (fPathResolver != null && node != null) {
 			IASTFileLocation loc= node.getFileLocation();
@@ -265,7 +303,7 @@ public class WritablePDOM extends PDOM implements IWritableIndexFragment {
 					IIndexFileLocation location = fPathResolver.resolveASTPath(loc.getFileName());
 					if (uncommittedKey != null && uncommittedKey.equals(new FileContentKey(linkageID, location, sigMacros)))
 						return fileBeingUpdated != null ? fileBeingUpdated : uncommittedFile;
-					return getFile(linkageID, location, sigMacros);
+					return getBestFile(linkageID, location, node.getTranslationUnit().getOriginatingTranslationUnit());
 				}
 			}
 		}

core/org.eclipse.cdt.ui.tests/ui/org/eclipse/cdt/ui/tests/text/contentassist2/CompletionTests.java

@@ -1308,8 +1308,27 @@ public class CompletionTests extends AbstractContentAssistTest {
 	//	void foo() {
 	//	    __LINE__;
 	//	}
-	public void testLineMacro_Bug412463() throws Exception {
+	public void testPreprocessorProvidedMacro_Bug412463() throws Exception {
 		final String[] expected = { "Cat", "meow(void)" };
 		assertContentAssistResults(fCursorOffset, expected, true, COMPARE_ID_STRINGS);
 	}
+	
+	//	struct Cat {
+	//	    void meow();
+	//	};
+	//
+	//	struct Waldo {
+	//	    void bar() {
+	//	        c./*cursor*/
+	//	    }
+	//
+	//	    Cat c;
+	//	};
+	//
+	//	int x = __CDT_PARSER__;
+	public void testPredefinedMacro_Bug412463() throws Exception {
+		final String[] expected = { "Cat", "meow(void)" };
+		assertContentAssistResults(fCursorOffset, expected, true, COMPARE_ID_STRINGS);
+	}
+
 }