package org.jruby.runtime.scope;
import org.jruby.RubyArray;
import org.jruby.javasupport.util.RuntimeHelpers;
import org.jruby.parser.BlockStaticScope;
import org.jruby.parser.StaticScope;
import org.jruby.runtime.DynamicScope;
import org.jruby.runtime.builtin.IRubyObject;
/**
* This is a DynamicScope that supports exactly four variables.
*/
public class FourVarDynamicScope extends ThreeVarDynamicScope {
private static final int SIZE = 4;
private static final String SIZE_ERROR = "FourVarDynamicScope only supports scopes with four variables";
private static final String GROW_ERROR = "FourVarDynamicScope cannot be grown; use ManyVarsDynamicScope";
protected IRubyObject variableValueThree;
public FourVarDynamicScope(StaticScope staticScope, DynamicScope parent) {
super(staticScope, parent);
}
public FourVarDynamicScope(StaticScope staticScope) {
super(staticScope);
}
@Override
public void growIfNeeded() {
if (staticScope.getNumberOfVariables() != SIZE) {
throw new RuntimeException(GROW_ERROR);
}
}
@Override
public DynamicScope cloneScope() {
return new ThreeVarDynamicScope(staticScope, parent);
}
@Override
public IRubyObject[] getValues() {
return new IRubyObject[] {variableValueZero, variableValueOne, variableValueTwo, variableValueThree};
}
/**
* Get value from current scope or one of its captured scopes.
*
* FIXME: block variables are not getting primed to nil so we need to null check those
* until we prime them properly. Also add assert back in.
*
* @param offset zero-indexed value that represents where variable lives
* @param depth how many captured scopes down this variable should be set
* @return the value here
*/
@Override
public IRubyObject getValue(int offset, int depth) {
if (depth > 0) {
return parent.getValue(offset, depth - 1);
}
assert offset < SIZE : SIZE_ERROR;
switch (offset) {
case 0:
return variableValueZero;
case 1:
return variableValueOne;
case 2:
return variableValueTwo;
case 3:
return variableValueThree;
default:
throw new RuntimeException(SIZE_ERROR);
}
}
/**
* Variation of getValue that checks for nulls, returning and setting the given value (presumably nil)
*/
@Override
public IRubyObject getValueOrNil(int offset, int depth, IRubyObject nil) {
if (depth > 0) {
return parent.getValueOrNil(offset, depth - 1, nil);
} else {
return getValueDepthZeroOrNil(offset, nil);
}
}
@Override
public IRubyObject getValueDepthZeroOrNil(int offset, IRubyObject nil) {
assert offset < SIZE : SIZE_ERROR;
switch (offset) {
case 0:
if (variableValueZero == null) return variableValueZero = nil;
return variableValueZero;
case 1:
if (variableValueOne == null) return variableValueOne = nil;
return variableValueOne;
case 2:
if (variableValueTwo == null) return variableValueTwo = nil;
return variableValueTwo;
case 3:
if (variableValueThree == null) return variableValueThree = nil;
return variableValueThree;
default:
throw new RuntimeException(SIZE_ERROR);
}
}
@Override
public IRubyObject getValueThreeDepthZeroOrNil(IRubyObject nil) {
if (variableValueThree == null) return variableValueThree = nil;
return variableValueThree;
}
/**
* Set value in current dynamic scope or one of its captured scopes.
*
* @param offset zero-indexed value that represents where variable lives
* @param value to set
* @param depth how many captured scopes down this variable should be set
*/
@Override
public IRubyObject setValue(int offset, IRubyObject value, int depth) {
if (depth > 0) {
assert parent != null : "If depth > 0, then parent should not ever be null";
return parent.setValue(offset, value, depth - 1);
} else {
assert offset < SIZE : SIZE_ERROR;
switch (offset) {
case 0:
return variableValueZero = value;
case 1:
return variableValueOne = value;
case 2:
return variableValueTwo = value;
case 3:
return variableValueThree = value;
default:
throw new RuntimeException(SIZE_ERROR);
}
}
}
@Override
public IRubyObject setValueDepthZero(IRubyObject value, int offset) {
assert offset < SIZE : SIZE_ERROR;
switch (offset) {
case 0:
return variableValueZero = value;
case 1:
return variableValueOne = value;
case 2:
return variableValueTwo = value;
case 3:
return variableValueThree = value;
default:
throw new RuntimeException(SIZE_ERROR);
}
}
@Override
public IRubyObject setValueThreeDepthZero(IRubyObject value) {
return variableValueThree = value;
}
/**
* Set all values which represent 'normal' parameters in a call list to this dynamic
* scope. Function calls bind to local scopes by assuming that the indexes or the
* arg list correspond to that of the local scope (plus 2 since $_ and $~ always take
* the first two slots). We pass in a second argument because we sometimes get more
* values than we are expecting. The rest get compacted by original caller into
* rest args.
*
* @param values up to size specified to be mapped as ordinary parm values
* @param size is the number of values to assign as ordinary parm values
*/
@Override
public void setArgValues(IRubyObject[] values, int size) {
assert size <= SIZE : SIZE_ERROR;
switch (size) {
case 4:
variableValueThree = values[3];
case 3:
variableValueTwo = values[2];
case 2:
variableValueOne = values[1];
case 1:
variableValueZero = values[0];
}
}
@Override
public void setArgValues(IRubyObject arg0) {
variableValueZero = arg0;
}
@Override
public void setArgValues(IRubyObject arg0, IRubyObject arg1) {
variableValueZero = arg0;
variableValueOne = arg1;
}
@Override
public void setArgValues(IRubyObject arg0, IRubyObject arg1, IRubyObject arg2) {
variableValueZero = arg0;
variableValueOne = arg1;
variableValueTwo = arg2;
}
@Override
public IRubyObject[] getArgValues() {
// if we're not the "argument scope" for zsuper, try our parent
if (!staticScope.isArgumentScope()) {
return parent.getArgValues();
}
int totalArgs = staticScope.getRequiredArgs() + staticScope.getOptionalArgs();
assert totalArgs <= SIZE : SIZE_ERROR;
// copy and splat arguments out of the scope to use for zsuper call
if (staticScope.getRestArg() < 0) {
switch (totalArgs) {
case 0:
return IRubyObject.NULL_ARRAY;
case 1:
return new IRubyObject[] {variableValueZero};
case 2:
return new IRubyObject[] {variableValueZero, variableValueOne};
case 3:
return new IRubyObject[] {variableValueZero, variableValueOne, variableValueTwo};
case 4:
return new IRubyObject[] {variableValueZero, variableValueOne, variableValueTwo, variableValueThree};
default:
throw new RuntimeException("more args requested than available variables");
}
} else {
// rest arg must be splatted
IRubyObject restArg = getValue(staticScope.getRestArg(), 0);
assert restArg != null;
// FIXME: not very efficient
RubyArray splattedArgs = RuntimeHelpers.splatValue(restArg);
IRubyObject[] argValues = new IRubyObject[totalArgs + splattedArgs.size()];
System.arraycopy(splattedArgs.toJavaArray(), 0, argValues, totalArgs, splattedArgs.size());
switch (totalArgs) {
case 4:
argValues[3] = variableValueThree;
case 3:
argValues[2] = variableValueTwo;
case 2:
argValues[1] = variableValueOne;
case 1:
argValues[0] = variableValueZero;
}
return argValues;
}
}
@Override
public String toString(StringBuffer buf, String indent) {
buf.append(indent).append("Static Type[" + hashCode() + "]: " +
(staticScope instanceof BlockStaticScope ? "block" : "local")+" [");
String names[] = staticScope.getVariables();
buf.append(names[0]).append("=");
if (variableValueZero == null) {
buf.append("null");
} else {
buf.append(variableValueZero);
}
buf.append(",");
if (variableValueOne == null) {
buf.append("null");
} else {
buf.append(variableValueOne);
}
buf.append(",");
if (variableValueTwo == null) {
buf.append("null");
} else {
buf.append(variableValueTwo);
}
buf.append(",");
if (variableValueThree == null) {
buf.append("null");
} else {
buf.append(variableValueThree);
}
buf.append("]");
if (parent != null) {
buf.append("\n");
parent.toString(buf, indent + " ");
}
return buf.toString();
}
}