Editors: Refactor auto-complete code out of the editors for better reusability.

Reviewed-by: Thorbjorn Lindeijer

src/plugins/qmljseditor/qmljsautocompleter.cpp

@@ -0,0 +1,279 @@
+/**************************************************************************
+**
+** This file is part of Qt Creator
+**
+** Copyright (c) 2010 Nokia Corporation and/or its subsidiary(-ies).
+**
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** Commercial Usage
+**
+** Licensees holding valid Qt Commercial licenses may use this file in
+** accordance with the Qt Commercial License Agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Nokia.
+**
+** GNU Lesser General Public License Usage
+**
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** If you are unsure which license is appropriate for your use, please
+** contact the sales department at http://qt.nokia.com/contact.
+**
+**************************************************************************/
+
+#include "qmljsautocompleter.h"
+
+#include <qmljs/qmljsscanner.h>
+
+#include <QtCore/QChar>
+#include <QtCore/QLatin1Char>
+#include <QtGui/QTextDocument>
+#include <QtGui/QTextCursor>
+#include <QtGui/QTextBlock>
+
+using namespace QmlJSEditor;
+using namespace Internal;
+using namespace QmlJS;
+
+static int blockStartState(const QTextBlock &block)
+{
+    int state = block.userState();
+
+    if (state == -1)
+        return 0;
+    else
+        return state & 0xff;
+}
+
+static Token tokenUnderCursor(const QTextCursor &cursor)
+{
+    const QString blockText = cursor.block().text();
+    const int blockState = blockStartState(cursor.block());
+
+    Scanner tokenize;
+    const QList<Token> tokens = tokenize(blockText, blockState);
+    const int pos = cursor.positionInBlock();
+
+    int tokenIndex = 0;
+    for (; tokenIndex < tokens.size(); ++tokenIndex) {
+        const Token &token = tokens.at(tokenIndex);
+
+        if (token.is(Token::Comment) || token.is(Token::String)) {
+            if (pos > token.begin() && pos <= token.end())
+                break;
+        } else {
+            if (pos >= token.begin() && pos < token.end())
+                break;
+        }
+    }
+
+    if (tokenIndex != tokens.size())
+        return tokens.at(tokenIndex);
+
+    return Token();
+}
+
+static bool shouldInsertMatchingText(QChar lookAhead)
+{
+    switch (lookAhead.unicode()) {
+    case '{': case '}':
+    case ']': case ')':
+    case ';': case ',':
+    case '"': case '\'':
+        return true;
+
+    default:
+        if (lookAhead.isSpace())
+            return true;
+
+        return false;
+    } // switch
+}
+
+static bool shouldInsertMatchingText(const QTextCursor &tc)
+{
+    QTextDocument *doc = tc.document();
+    return shouldInsertMatchingText(doc->characterAt(tc.selectionEnd()));
+}
+
+static bool shouldInsertNewline(const QTextCursor &tc)
+{
+    QTextDocument *doc = tc.document();
+    int pos = tc.selectionEnd();
+
+    // count the number of empty lines.
+    int newlines = 0;
+    for (int e = doc->characterCount(); pos != e; ++pos) {
+        const QChar ch = doc->characterAt(pos);
+
+        if (! ch.isSpace())
+            break;
+        else if (ch == QChar::ParagraphSeparator)
+            ++newlines;
+    }
+
+    if (newlines <= 1 && doc->characterAt(pos) != QLatin1Char('}'))
+        return true;
+
+    return false;
+}
+
+static bool isCompleteStringLiteral(const QStringRef &text)
+{
+    if (text.length() < 2)
+        return false;
+
+    const QChar quote = text.at(0);
+
+    if (text.at(text.length() - 1) == quote)
+        return text.at(text.length() - 2) != QLatin1Char('\\'); // ### not exactly.
+
+    return false;
+}
+
+AutoCompleter::AutoCompleter()
+{}
+
+AutoCompleter::~AutoCompleter()
+{}
+
+bool AutoCompleter::doContextAllowsAutoParentheses(const QTextCursor &cursor,
+                                                   const QString &textToInsert) const
+{
+    QChar ch;
+
+    if (! textToInsert.isEmpty())
+        ch = textToInsert.at(0);
+
+    switch (ch.unicode()) {
+    case '\'':
+    case '"':
+
+    case '(':
+    case '[':
+    case '{':
+
+    case ')':
+    case ']':
+    case '}':
+
+    case ';':
+        break;
+
+    default:
+        if (ch.isNull())
+            break;
+
+        return false;
+    } // end of switch
+
+    const Token token = tokenUnderCursor(cursor);
+    switch (token.kind) {
+    case Token::Comment:
+        return false;
+
+    case Token::String: {
+        const QString blockText = cursor.block().text();
+        const QStringRef tokenText = blockText.midRef(token.offset, token.length);
+        const QChar quote = tokenText.at(0);
+
+        if (ch != quote || isCompleteStringLiteral(tokenText))
+            break;
+
+        return false;
+    }
+
+    default:
+        break;
+    } // end of switch
+
+    return true;
+}
+
+bool AutoCompleter::doContextAllowsElectricCharacters(const QTextCursor &cursor) const
+{
+    Token token = tokenUnderCursor(cursor);
+    switch (token.kind) {
+    case Token::Comment:
+    case Token::String:
+        return false;
+    default:
+        return true;
+    }
+}
+
+bool AutoCompleter::doIsInComment(const QTextCursor &cursor) const
+{
+    return tokenUnderCursor(cursor).is(Token::Comment);
+}
+
+QString AutoCompleter::doInsertMatchingBrace(const QTextCursor &cursor,
+                                             const QString &text,
+                                             QChar,
+                                             int *skippedChars) const
+{
+    if (text.length() != 1)
+        return QString();
+
+    if (! shouldInsertMatchingText(cursor))
+        return QString();
+
+    const QChar la = cursor.document()->characterAt(cursor.position());
+
+    const QChar ch = text.at(0);
+    switch (ch.unicode()) {
+    case '\'':
+        if (la != ch)
+            return QString(ch);
+        ++*skippedChars;
+        break;
+
+    case '"':
+        if (la != ch)
+            return QString(ch);
+        ++*skippedChars;
+        break;
+
+    case '(':
+        return QString(QLatin1Char(')'));
+
+    case '[':
+        return QString(QLatin1Char(']'));
+
+    case '{':
+        return QString(); // nothing to do.
+
+    case ')':
+    case ']':
+    case '}':
+    case ';':
+        if (la == ch)
+            ++*skippedChars;
+        break;
+
+    default:
+        break;
+    } // end of switch
+
+    return QString();
+}
+
+QString AutoCompleter::doInsertParagraphSeparator(const QTextCursor &cursor) const
+{
+    if (shouldInsertNewline(cursor)) {
+        QTextCursor cursor = cursor;
+        cursor.movePosition(QTextCursor::EndOfBlock, QTextCursor::KeepAnchor);
+        if (! cursor.selectedText().trimmed().isEmpty())
+            return QString();
+
+        return QLatin1String("}\n");
+    }
+
+    return QLatin1String("}");
+}