C++: fix multi-line continuation handling.

When having doxygen enabled, but leading astriskses disabled, a comment
continuation line did not insert an extra space for where the astrisks
would have been, thus mis-aligning the second line.

Task-number: QTCREATORBUG-12539
Change-Id: I47baa203fd5d9279fa89a06f526f3abed06ce443
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@theqtcompany.com>

src/plugins/cppeditor/cppdocumentationcommenthelper.cpp

@@ -182,44 +182,53 @@ bool handleDoxygenContinuation(QTextCursor &cursor,
     if (enableDoxygen && !cursor.atEnd() && isCursorAfterCppComment(cursor, doc))
         return handleDoxygenCppStyleContinuation(cursor, e);
 
-    if (!leadingAsterisks)
-        return false;
-
     // We continue the comment if the cursor is after a comment's line asterisk and if
     // there's no asterisk immediately after the cursor (that would already be considered
     // a leading asterisk).
     int offset = 0;
     const int blockPos = cursor.positionInBlock();
-    const QString &text = cursor.block().text();
+    const QString &currentLine = cursor.block().text();
     for (; offset < blockPos; ++offset) {
-        if (!text.at(offset).isSpace())
+        if (!currentLine.at(offset).isSpace())
             break;
     }
 
+    // In case we don't need to insert leading asteriskses, this code will be run once (right after
+    // hitting enter on the line containing '/*'). It will insert a continuation without an
+    // asterisk, but with an extra space. After that, the normal indenting will take over and do the
+    // Right Thing <TM>.
     if (offset < blockPos
-            && (text.at(offset) == QLatin1Char('*')
+            && (currentLine.at(offset) == QLatin1Char('*')
                 || (offset < blockPos - 1
-                    && text.at(offset) == QLatin1Char('/')
-                    && text.at(offset + 1) == QLatin1Char('*')))) {
+                    && currentLine.at(offset) == QLatin1Char('/')
+                    && currentLine.at(offset + 1) == QLatin1Char('*')))) {
+        // Ok, so the line started with an '*' or '/*'
         int followinPos = blockPos;
-        for (; followinPos < text.length(); ++followinPos) {
-            if (!text.at(followinPos).isSpace())
+        // Now search for the first non-whitespace character to align to:
+        for (; followinPos < currentLine.length(); ++followinPos) {
+            if (!currentLine.at(followinPos).isSpace())
                 break;
         }
-        if (followinPos == text.length()
-                || text.at(followinPos) != QLatin1Char('*')) {
+        if (followinPos == currentLine.length() // a)
+                || currentLine.at(followinPos) != QLatin1Char('*')) { // b)
+            // So either a) the line ended after a '*' and we need to insert a continuation, or
+            // b) we found the start of some text and we want to align the continuation to that.
             QString newLine(QLatin1Char('\n'));
             QTextCursor c(cursor);
             c.movePosition(QTextCursor::StartOfBlock);
             c.movePosition(QTextCursor::NextCharacter, QTextCursor::KeepAnchor, offset);
             newLine.append(c.selectedText());
-            if (text.at(offset) == QLatin1Char('/')) {
-                newLine.append(QLatin1String(" * "));
+            if (currentLine.at(offset) == QLatin1Char('/')) {
+                if (leadingAsterisks)
+                    newLine.append(QLatin1String(" * "));
+                else
+                    newLine.append(QLatin1String("   "));
             } else {
                 int start = offset;
-                while (offset < blockPos && text.at(offset) == QLatin1Char('*'))
+                while (offset < blockPos && currentLine.at(offset) == QLatin1Char('*'))
                     ++offset;
-                newLine.append(QString(offset - start, QLatin1Char('*')));
+                const QChar ch = leadingAsterisks ? QLatin1Char('*') : QLatin1Char(' ');
+                newLine.append(QString(offset - start, ch));
                 newLine.append(QLatin1Char(' '));
             }
             cursor.insertText(newLine);

src/plugins/cppeditor/cppdoxygen_test.cpp

@@ -32,7 +32,9 @@
 #include "cppeditortestcase.h"
 
 #include <coreplugin/editormanager/editormanager.h>
+#include <cpptools/commentssettings.h>
 #include <cpptools/cppmodelmanager.h>
+#include <cpptools/cpptoolssettings.h>
 
 #include <cplusplus/CppDocument.h>
 #include <utils/fileutils.h>
@@ -63,9 +65,11 @@ namespace Tests {
 
 class DoxygenTestCase : public Internal::Tests::TestCase
 {
+    QScopedPointer<CppTools::CommentsSettings> oldSettings;
 public:
     /// The '|' in the input denotes the cursor position.
-    DoxygenTestCase(const QByteArray &original, const QByteArray &expected)
+    DoxygenTestCase(const QByteArray &original, const QByteArray &expected,
+                    CppTools::CommentsSettings *injectedSettings = 0)
     {
         QVERIFY(succeededSoFar());
 
@@ -82,6 +86,12 @@ public:
                               &testDocument.m_editorWidget));
         closeEditorAtEndOfTestCase(testDocument.m_editor);
 
+        if (injectedSettings) {
+            auto *cts = CppTools::CppToolsSettings::instance();
+            oldSettings.reset(new CppTools::CommentsSettings(cts->commentsSettings()));
+            injectSettings(injectedSettings);
+        }
+
         // We want to test documents that start with a comment. By default, the
         // editor will fold the very first comment it encounters, assuming
         // it is a license header. Currently unfoldAll() does not work as
@@ -104,6 +114,19 @@ public:
         const QString contentsAfterUndo = testDocument.m_editorWidget->document()->toPlainText();
         QCOMPARE(contentsAfterUndo, testDocument.m_source);
     }
+
+    ~DoxygenTestCase()
+    {
+        if (oldSettings)
+            injectSettings(oldSettings.data());
+    }
+
+    static void injectSettings(CppTools::CommentsSettings *injection)
+    {
+        auto *cts = CppTools::CppToolsSettings::instance();
+        QVERIFY(QMetaObject::invokeMethod(cts, "commentsSettingsChanged", Qt::DirectConnection,
+                                          Q_ARG(CppTools::CommentsSettings, *injection)));
+    }
 };
 
 } // namespace Tests
@@ -254,5 +277,30 @@ void CppEditorPlugin::test_doxygen_comments()
     Tests::DoxygenTestCase(given, expected);
 }
 
+void CppEditorPlugin::test_doxygen_comments_no_leading_asterisks_data()
+{
+    QTest::addColumn<QByteArray>("given");
+    QTest::addColumn<QByteArray>("expected");
+
+    QTest::newRow("cpp_style_no_astrix") << _(
+            "/* asdf asdf|\n"
+        ) << _(
+            "/* asdf asdf\n"
+            "   \n"
+    );
+}
+
+void CppEditorPlugin::test_doxygen_comments_no_leading_asterisks()
+{
+    QFETCH(QByteArray, given);
+    QFETCH(QByteArray, expected);
+
+    CppTools::CommentsSettings injection;
+    injection.m_enableDoxygen = true;
+    injection.m_leadingAsterisks = false;
+
+    Tests::DoxygenTestCase(given, expected, &injection);
+}
+
 } // namespace Internal
 } // namespace CppEditor

src/plugins/cppeditor/cppeditorplugin.h

@@ -118,6 +118,8 @@ private slots:
 
     void test_doxygen_comments_data();
     void test_doxygen_comments();
+    void test_doxygen_comments_no_leading_asterisks_data();
+    void test_doxygen_comments_no_leading_asterisks();
 
     void test_quickfix_data();
     void test_quickfix();