TimeDiff.java

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package org.apache.doris.nereids.trees.expressions.functions.scalar;

import org.apache.doris.catalog.FunctionSignature;
import org.apache.doris.nereids.trees.expressions.Expression;
import org.apache.doris.nereids.trees.expressions.functions.ExplicitlyCastableSignature;
import org.apache.doris.nereids.trees.expressions.functions.PropagateNullableOnDateOrTimeLikeV2Args;
import org.apache.doris.nereids.trees.expressions.shape.BinaryExpression;
import org.apache.doris.nereids.trees.expressions.visitor.ExpressionVisitor;
import org.apache.doris.nereids.types.DateTimeV2Type;
import org.apache.doris.nereids.types.DateV2Type;
import org.apache.doris.nereids.types.TimeV2Type;

import com.google.common.base.Preconditions;
import com.google.common.collect.ImmutableList;

import java.util.List;

/**
 * ScalarFunction 'timediff'. This class is generated by GenerateFunction.
 */
public class TimeDiff extends ScalarFunction
        implements BinaryExpression, ExplicitlyCastableSignature, PropagateNullableOnDateOrTimeLikeV2Args {

    private static final List<FunctionSignature> SIGNATURES = ImmutableList.of(
            FunctionSignature.ret(TimeV2Type.INSTANCE)
                    .args(DateTimeV2Type.SYSTEM_DEFAULT, DateTimeV2Type.SYSTEM_DEFAULT),
            FunctionSignature.ret(TimeV2Type.INSTANCE).args(DateTimeV2Type.SYSTEM_DEFAULT, DateV2Type.INSTANCE),
            FunctionSignature.ret(TimeV2Type.INSTANCE).args(DateV2Type.INSTANCE, DateTimeV2Type.SYSTEM_DEFAULT),
            FunctionSignature.ret(TimeV2Type.INSTANCE).args(DateV2Type.INSTANCE, DateV2Type.INSTANCE));

    /**
     * constructor with 2 arguments.
     */
    public TimeDiff(Expression arg0, Expression arg1) {
        super("timediff", arg0, arg1);
    }

    /**
     * withChildren.
     */
    @Override
    public TimeDiff withChildren(List<Expression> children) {
        Preconditions.checkArgument(children.size() == 2);
        return new TimeDiff(children.get(0), children.get(1));
    }

    @Override
    public List<FunctionSignature> getSignatures() {
        return SIGNATURES;
    }

    @Override
    public <R, C> R accept(ExpressionVisitor<R, C> visitor, C context) {
        return visitor.visitTimeDiff(this, context);
    }

    @Override
    public FunctionSignature computeSignature(FunctionSignature signature) {
        signature = super.computeSignature(signature);
        boolean useTimev2 = false;
        int scale = 0;
        if (getArgument(0).getDataType() instanceof DateTimeV2Type) {
            DateTimeV2Type left = (DateTimeV2Type) getArgument(0).getDataType();
            scale = Math.max(scale, left.getScale());
            useTimev2 = true;
        }
        if (getArgument(1).getDataType() instanceof DateTimeV2Type) {
            DateTimeV2Type right = (DateTimeV2Type) getArgument(1).getDataType();
            scale = Math.max(scale, right.getScale());
            useTimev2 = true;
        }
        if (useTimev2) {
            signature = signature.withReturnType(TimeV2Type.of(scale));
        }
        return signature;
    }
}