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 * (b) any piece of software and/or hardware listed in the lrgrwrks.txt file if
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package com.oracle.graal.python.builtins.objects.contextvars;

import static com.oracle.graal.python.builtins.PythonBuiltinClassType.LookupError;
import static com.oracle.graal.python.builtins.PythonBuiltinClassType.TypeError;
import static com.oracle.graal.python.builtins.PythonBuiltinClassType.ValueError;
import static com.oracle.graal.python.util.PythonUtils.tsLiteral;

import java.util.List;

import com.oracle.graal.python.builtins.Builtin;
import com.oracle.graal.python.builtins.CoreFunctions;
import com.oracle.graal.python.builtins.PythonBuiltinClassType;
import com.oracle.graal.python.builtins.PythonBuiltins;
import com.oracle.graal.python.builtins.objects.PNone;
import com.oracle.graal.python.nodes.ErrorMessages;
import com.oracle.graal.python.nodes.PRaiseNode;
import com.oracle.graal.python.nodes.function.PythonBuiltinBaseNode;
import com.oracle.graal.python.nodes.function.builtins.PythonBinaryBuiltinNode;
import com.oracle.graal.python.runtime.PythonContext;
import com.oracle.truffle.api.dsl.Cached;
import com.oracle.truffle.api.dsl.GenerateNodeFactory;
import com.oracle.truffle.api.dsl.NodeFactory;
import com.oracle.truffle.api.dsl.Specialization;
import com.oracle.truffle.api.frame.VirtualFrame;
import com.oracle.truffle.api.strings.TruffleString;

@CoreFunctions(extendClasses = PythonBuiltinClassType.ContextVar)
public final class ContextVarBuiltins extends PythonBuiltins {

    private static final TruffleString T_VALUE = tsLiteral("value");

    @Override
    protected List<? extends NodeFactory<? extends PythonBuiltinBaseNode>> getNodeFactories() {
        return ContextVarBuiltinsFactory.getFactories();
    }

    @Builtin(name = "get", minNumOfPositionalArgs = 1, maxNumOfPositionalArgs = 2)
    @GenerateNodeFactory
    public abstract static class GetNode extends PythonBinaryBuiltinNode {
        @Specialization(guards = "isNoValue(def)")
        Object get(VirtualFrame frame, PContextVar self, PNone def) {
            return get(frame, self, PContextVar.NO_DEFAULT);
        }

        @Specialization(guards = "!isNoValue(def)")
        Object get(VirtualFrame frame, PContextVar self, Object def) {
            PythonContext.PythonThreadState threadState = getContext().getThreadState(getLanguage());
            Object value = self.getValue(threadState);
            if (value != null) {
                return value;
            }
            if (def != PContextVar.NO_DEFAULT) {
                return def;
            }
            if (self.getDefault() != PContextVar.NO_DEFAULT) {
                return self.getDefault();
            }
            throw raise(LookupError, new Object[]{self});
        }
    }

    @Builtin(name = "set", minNumOfPositionalArgs = 2)
    @GenerateNodeFactory
    public abstract static class SetNode extends PythonBinaryBuiltinNode {
        @Specialization
        Object set(VirtualFrame frame, PContextVar self, Object value) {
            PythonContext.PythonThreadState threadState = getContext().getThreadState(getLanguage());
            Object oldValue = self.getValue(threadState);
            self.setValue(threadState, value);
            return factory().createContextVarsToken(self, oldValue);
        }
    }

    @Builtin(name = "reset", minNumOfPositionalArgs = 2)
    @GenerateNodeFactory
    public abstract static class ResetNode extends PythonBinaryBuiltinNode {
        @Specialization
        Object reset(PContextVar self, PContextVarsToken token,
                        @Cached PRaiseNode raise) {
            if (self == token.getVar()) {
                token.use(raise);
                PythonContext.PythonThreadState threadState = getContext().getThreadState(getLanguage());
                if (token.getOldValue() == null) {
                    PContextVarsContext context = threadState.getContextVarsContext();
                    context.contextVarValues = context.contextVarValues.without(self, self.getHash());
                } else {
                    self.setValue(threadState, token.getOldValue());
                }
            } else {
                throw raise.raise(ValueError, ErrorMessages.TOKEN_FOR_DIFFERENT_CONTEXTVAR, token);
            }
            return PNone.NONE;
        }

        @Specialization
        Object doError(PContextVar self, Object token,
                        @Cached PRaiseNode raise) {
            throw raise.raise(TypeError, ErrorMessages.INSTANCE_OF_TOKEN_EXPECTED, token);
        }
    }

    @Builtin(name = "__class_getitem__", minNumOfPositionalArgs = 2, isClassmethod = true)
    @GenerateNodeFactory
    public abstract static class ClassGetItemNode extends PythonBinaryBuiltinNode {
        @Specialization
        static Object classGetItem(Object cls, Object key) {
            return cls; // TODO: use a GenericAlias
        }
    }
}
