/*
* Copyright 2012 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.toBooleanJavaExpr;
import com.google.common.collect.ImmutableSet;
import com.google.common.collect.Lists;
import com.google.inject.Inject;
import com.google.inject.Singleton;
import com.google.template.soy.data.SoyData;
import com.google.template.soy.data.restricted.BooleanData;
import com.google.template.soy.data.restricted.NullData;
import com.google.template.soy.data.restricted.UndefinedData;
import com.google.template.soy.exprtree.Operator;
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.SoyJsCodeUtils;
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 checks whether its argument is a defined nonnull value.
*
* @author Kai Huang
*/
@Singleton
@SoyPureFunction
class IsNonnullFunction extends SoyAbstractTofuFunction
implements SoyJsSrcFunction, SoyJavaSrcFunction {
@Inject
IsNonnullFunction() {}
@Override public String getName() {
return "isNonnull";
}
@Override public Set<Integer> getValidArgsSizes() {
return ImmutableSet.of(1);
}
@Override public SoyData compute(List<SoyData> args) {
SoyData arg = args.get(0);
return BooleanData.forValue(! (arg instanceof UndefinedData || arg instanceof NullData));
}
@Override public JsExpr computeForJsSrc(List<JsExpr> args) {
JsExpr arg = args.get(0);
JsExpr nullJsExpr = new JsExpr("null", Integer.MAX_VALUE);
// Note: In JavaScript, "x != null" is equivalent to "x !== undefined && x !== null".
return SoyJsCodeUtils.genJsExprUsingSoySyntax(
Operator.NOT_EQUAL, Lists.<JsExpr>newArrayList(arg, nullJsExpr));
}
@Override public JavaExpr computeForJavaSrc(List<JavaExpr> args) {
JavaExpr arg = args.get(0);
return toBooleanJavaExpr(
JavaCodeUtils.genFunctionCall(JavaCodeUtils.UTILS_LIB + ".$$isNonnull", arg.getText()));
}
}