/*
* Copyright 2011 Google Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.google.common.css.compiler.passes;
import com.google.common.css.compiler.ast.CssCompilerPass;
import com.google.common.css.compiler.ast.CssNode;
import com.google.common.css.compiler.ast.CssNumericNode;
import com.google.common.css.compiler.ast.CssValueNode;
import com.google.common.css.compiler.ast.DefaultTreeVisitor;
import com.google.common.css.compiler.ast.ErrorManager;
import com.google.common.css.compiler.ast.GssError;
import com.google.common.css.compiler.ast.VisitController;
import java.util.Set;
/**
* Base class for compiler passes enforcing a specific CSS level.
*
* @author fbenz@google.com (Florian Benz)
*/
public abstract class StrictCssBase extends DefaultTreeVisitor
implements CssCompilerPass {
private static final String SUPPORTED_LIST_PREFIX = "\nsupported names: ";
private static final String SUPPORTED_LIST_SUFFIX = "\n";
static final String INVALID_UNIT_PREFIX = "Invalid unit: ";
protected final VisitController visitController;
protected final ErrorManager errorManager;
public StrictCssBase(VisitController visitController,
ErrorManager errorManager) {
this.visitController = visitController;
this.errorManager = errorManager;
}
abstract Set<String> getValidCssUnits();
/**
* Checks numeric nodes for valid units.
*/
@Override
public boolean enterValueNode(CssValueNode node) {
if (node instanceof CssNumericNode) {
// NOTE(nicksantos): At some point, we should attach type information
// to the AST so that we can validate by the type of unit.
String unit = ((CssNumericNode) node).getUnit();
if (!getValidCssUnits().contains(unit)) {
errorManager.report(
new GssError(INVALID_UNIT_PREFIX + unit,
node.getSourceCodeLocation()));
return false;
}
}
return true;
}
/**
* Adds a list of supported names to the error message and then reports
* the error.
*/
protected void reportUnsupported(CssNode node, String message,
Set<String> supportedNames) {
StringBuilder sb = new StringBuilder();
sb.append(message);
sb.append(SUPPORTED_LIST_PREFIX);
for (String name : supportedNames) {
sb.append(name);
sb.append(", ");
}
sb.append(SUPPORTED_LIST_SUFFIX);
errorManager.report(new GssError(sb.toString(),
node.getSourceCodeLocation()));
}
@Override
public void runPass() {
visitController.startVisit(this);
}
}