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 three variables.
*/
public class OneVarDynamicScope extends NoVarsDynamicScope {
protected IRubyObject variableValueZero;
public OneVarDynamicScope(StaticScope staticScope, DynamicScope parent) {
super(staticScope, parent);
}
public OneVarDynamicScope(StaticScope staticScope) {
super(staticScope);
}
@Override
public void growIfNeeded() {
if (staticScope.getNumberOfVariables() != 1) {
throw new RuntimeException("OneVarDynamicScope cannot be grown; use ManyVarsDynamicScope");
}
}
@Override
public DynamicScope cloneScope() {
return new OneVarDynamicScope(staticScope, parent);
}
@Override
public IRubyObject[] getValues() {
return new IRubyObject[] {variableValueZero};
}
/**
* 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 == 0 : "SingleVarDynamicScope only supports scopes with one variable";
return variableValueZero;
}
/**
* 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) {
assertGetValueDepthZeroOrNil(offset);
IRubyObject value = variableValueZero;
if (value == null) return variableValueZero = nil;
return value;
}
@Override
public IRubyObject getValueZeroDepthZeroOrNil(IRubyObject nil) {
IRubyObject value = variableValueZero;
if (value == null) return variableValueZero = nil;
return value;
}
/**
* 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) {
assertParent();
return parent.setValue(offset, value, depth - 1);
} else {
assertSetValue(offset);
return variableValueZero = value;
}
}
@Override
public IRubyObject setValueDepthZero(IRubyObject value, int offset) {
assertSetValueDepthZero(offset);
return variableValueZero = value;
}
@Override
public IRubyObject setValueZeroDepthZero(IRubyObject value) {
return variableValueZero = 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) {
assertSetArgValues(values);
if (size == 1) {
variableValueZero = values[0];
}
}
@Override
public void setArgValues(IRubyObject arg0) {
variableValueZero = arg0;
}
@Override
public void setArgValues(IRubyObject arg0, IRubyObject arg1) {
assert false : "SingleVarDynamicScope only supports one variable not two";
}
@Override
public void setArgValues(IRubyObject arg0, IRubyObject arg1, IRubyObject arg2) {
assert false : "SingleVarDynamicScope only supports one variable not three";
}
@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 <= 1 : "OneVarDynamicScope only supports one variable";
// copy and splat arguments out of the scope to use for zsuper call
if (staticScope.getRestArg() < 0) {
if (totalArgs == 1) {
return new IRubyObject[] {variableValueZero};
} else {
return IRubyObject.NULL_ARRAY;
}
} 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());
if (totalArgs == 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 (parent != null) {
buf.append("\n");
parent.toString(buf, indent + " ");
}
return buf.toString();
}
private void assertGetValueDepthZeroOrNil(int offset) {
assert offset == 0 : "SingleVarDynamicScope only supports scopes with one variable";
}
private void assertParent() {
assert parent != null : "If depth > 0, then parent should not ever be null";
}
private void assertSetArgValues(IRubyObject[] values) {
assert values.length == 1 : "SingleVarDynamicScope only supports one variable";
}
private void assertSetValue(int offset) {
assert offset == 0 : "SingleVarDynamicScope only supports one variable";
}
private void assertSetValueDepthZero(int offset) {
assert offset == 0 : "SingleVarDynamicScope only supports one variable";
}
}