/*
* Copyright 2009 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.template.soy.basicfunctions;
import static com.google.template.soy.javasrc.restricted.SoyJavaSrcFunctionUtils.toIntegerJavaExpr;
import static com.google.template.soy.shared.restricted.SoyJavaRuntimeFunctionUtils.toSoyData;
import com.google.common.collect.ImmutableSet;
import com.google.inject.Inject;
import com.google.inject.Singleton;
import com.google.template.soy.data.SoyData;
import com.google.template.soy.data.SoyListData;
import com.google.template.soy.javasrc.restricted.JavaCodeUtils;
import com.google.template.soy.javasrc.restricted.JavaExpr;
import com.google.template.soy.javasrc.restricted.SoyJavaSrcFunction;
import com.google.template.soy.jssrc.restricted.JsExpr;
import com.google.template.soy.jssrc.restricted.SoyJsSrcFunction;
import com.google.template.soy.shared.restricted.SoyPureFunction;
import com.google.template.soy.tofu.restricted.SoyAbstractTofuFunction;
import java.util.List;
import java.util.Set;
/**
* Soy function that gets the length of a list.
*
* @author Kai Huang
*/
@Singleton
@SoyPureFunction
class LengthFunction extends SoyAbstractTofuFunction
implements SoyJsSrcFunction, SoyJavaSrcFunction {
@Inject
LengthFunction() {}
@Override public String getName() {
return "length";
}
@Override public Set<Integer> getValidArgsSizes() {
return ImmutableSet.of(1);
}
@Override public SoyData compute(List<SoyData> args) {
SoyData arg = args.get(0);
if (!(arg instanceof SoyListData)) {
throw new IllegalArgumentException("Argument to length() function is not SoyListData.");
}
return toSoyData(((SoyListData) arg).length());
}
@Override public JsExpr computeForJsSrc(List<JsExpr> args) {
JsExpr arg = args.get(0);
String exprText = arg.getPrecedence() == Integer.MAX_VALUE ?
arg.getText() + ".length" : "(" + arg.getText() + ").length";
return new JsExpr(exprText, Integer.MAX_VALUE);
}
@Override public JavaExpr computeForJavaSrc(List<JavaExpr> args) {
JavaExpr arg = args.get(0);
return toIntegerJavaExpr(
JavaCodeUtils.genNewIntegerData(
"(" + JavaCodeUtils.genMaybeCast(arg, SoyListData.class) + ").length()"));
}
}