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/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
#include "txExpr.h"
#include "txNodeSet.h"
#include "txNodeSetContext.h"
#include "txSingleNodeContext.h"
#include "txXMLUtils.h"
#include "txXPathTreeWalker.h"
using mozilla::Unused;
using mozilla::WrapUnique;
//------------/
//- PathExpr -/
//------------/
/**
* Adds the Expr to this PathExpr
* @param expr the Expr to add to this PathExpr
**/
void PathExpr::addExpr(Expr* aExpr, PathOperator aPathOp) {
NS_ASSERTION(!mItems.IsEmpty() || aPathOp == RELATIVE_OP,
"First step has to be relative in PathExpr");
PathExprItem* pxi = mItems.AppendElement();
pxi->expr = WrapUnique(aExpr);
pxi->pathOp = aPathOp;
}
//-----------------------------/
//- Virtual methods from Expr -/
//-----------------------------/
/**
* Evaluates this Expr based on the given context node and processor state
* @param context the context node for evaluation of this Expr
* @param ps the ContextState containing the stack information needed
* for evaluation
* @return the result of the evaluation
**/
nsresult PathExpr::evaluate(txIEvalContext* aContext, txAExprResult** aResult) {
*aResult = nullptr;
// We need to evaluate the first step with the current context since it
// can depend on the context size and position. For example:
// key('books', concat('book', position()))
RefPtr<txAExprResult> res;
nsresult rv = mItems[0].expr->evaluate(aContext, getter_AddRefs(res));
NS_ENSURE_SUCCESS(rv, rv);
NS_ENSURE_TRUE(res->getResultType() == txAExprResult::NODESET,
NS_ERROR_XSLT_NODESET_EXPECTED);
RefPtr<txNodeSet> nodes =
static_cast<txNodeSet*>(static_cast<txAExprResult*>(res));
if (nodes->isEmpty()) {
res.forget(aResult);
return NS_OK;
}
res = nullptr; // To allow recycling
// Evaluate remaining steps
uint32_t i, len = mItems.Length();
for (i = 1; i < len; ++i) {
PathExprItem& pxi = mItems[i];
RefPtr<txNodeSet> tmpNodes;
txNodeSetContext eContext(nodes, aContext);
while (eContext.hasNext()) {
eContext.next();
RefPtr<txNodeSet> resNodes;
if (pxi.pathOp == DESCENDANT_OP) {
rv = aContext->recycler()->getNodeSet(getter_AddRefs(resNodes));
NS_ENSURE_SUCCESS(rv, rv);
rv = evalDescendants(pxi.expr.get(), eContext.getContextNode(),
&eContext, resNodes);
NS_ENSURE_SUCCESS(rv, rv);
} else {
RefPtr<txAExprResult> res;
rv = pxi.expr->evaluate(&eContext, getter_AddRefs(res));
NS_ENSURE_SUCCESS(rv, rv);
if (res->getResultType() != txAExprResult::NODESET) {
// XXX ErrorReport: report nonnodeset error
return NS_ERROR_XSLT_NODESET_EXPECTED;
}
resNodes = static_cast<txNodeSet*>(static_cast<txAExprResult*>(res));
}
if (tmpNodes) {
if (!resNodes->isEmpty()) {
RefPtr<txNodeSet> oldSet;
oldSet.swap(tmpNodes);
rv = aContext->recycler()->getNonSharedNodeSet(
oldSet, getter_AddRefs(tmpNodes));
NS_ENSURE_SUCCESS(rv, rv);
oldSet.swap(resNodes);
rv = aContext->recycler()->getNonSharedNodeSet(
oldSet, getter_AddRefs(resNodes));
NS_ENSURE_SUCCESS(rv, rv);
tmpNodes->addAndTransfer(resNodes);
}
} else {
tmpNodes = resNodes;
}
}
nodes = tmpNodes;
if (nodes->isEmpty()) {
break;
}
}
*aResult = nodes;
NS_ADDREF(*aResult);
return NS_OK;
} //-- evaluate
/**
* Selects from the descendants of the context node
* all nodes that match the Expr
**/
nsresult PathExpr::evalDescendants(Expr* aStep, const txXPathNode& aNode,
txIMatchContext* aContext,
txNodeSet* resNodes) {
txSingleNodeContext eContext(aNode, aContext);
RefPtr<txAExprResult> res;
nsresult rv = aStep->evaluate(&eContext, getter_AddRefs(res));
NS_ENSURE_SUCCESS(rv, rv);
if (res->getResultType() != txAExprResult::NODESET) {
// XXX ErrorReport: report nonnodeset error
return NS_ERROR_XSLT_NODESET_EXPECTED;
}
txNodeSet* oldSet = static_cast<txNodeSet*>(static_cast<txAExprResult*>(res));
RefPtr<txNodeSet> newSet;
rv =
aContext->recycler()->getNonSharedNodeSet(oldSet, getter_AddRefs(newSet));
NS_ENSURE_SUCCESS(rv, rv);
resNodes->addAndTransfer(newSet);
bool filterWS;
rv = aContext->isStripSpaceAllowed(aNode, filterWS);
NS_ENSURE_SUCCESS(rv, rv);
txXPathTreeWalker walker(aNode);
if (!walker.moveToFirstChild()) {
return NS_OK;
}
do {
const txXPathNode& node = walker.getCurrentPosition();
if (!(filterWS && txXPathNodeUtils::isText(node) &&
txXPathNodeUtils::isWhitespace(node))) {
rv = evalDescendants(aStep, node, aContext, resNodes);
NS_ENSURE_SUCCESS(rv, rv);
}
} while (walker.moveToNextSibling());
return NS_OK;
} //-- evalDescendants
Expr::ExprType PathExpr::getType() { return PATH_EXPR; }
TX_IMPL_EXPR_STUBS_BASE(PathExpr, NODESET_RESULT)
Expr* PathExpr::getSubExprAt(uint32_t aPos) {
return aPos < mItems.Length() ? mItems[aPos].expr.get() : nullptr;
}
void PathExpr::setSubExprAt(uint32_t aPos, Expr* aExpr) {
NS_ASSERTION(aPos < mItems.Length(), "setting bad subexpression index");
Unused << mItems[aPos].expr.release();
mItems[aPos].expr = WrapUnique(aExpr);
}
bool PathExpr::isSensitiveTo(ContextSensitivity aContext) {
if (mItems[0].expr->isSensitiveTo(aContext)) {
return true;
}
// We're creating a new node/nodeset so we can ignore those bits.
Expr::ContextSensitivity context =
aContext & ~(Expr::NODE_CONTEXT | Expr::NODESET_CONTEXT);
if (context == NO_CONTEXT) {
return false;
}
uint32_t i, len = mItems.Length();
for (i = 0; i < len; ++i) {
NS_ASSERTION(!mItems[i].expr->isSensitiveTo(Expr::NODESET_CONTEXT),
"Step cannot depend on nodeset-context");
if (mItems[i].expr->isSensitiveTo(context)) {
return true;
}
}
return false;
}
#ifdef TX_TO_STRING
void PathExpr::toString(nsAString& dest) {
if (!mItems.IsEmpty()) {
NS_ASSERTION(mItems[0].pathOp == RELATIVE_OP,
"First step should be relative");
mItems[0].expr->toString(dest);
}
uint32_t i, len = mItems.Length();
for (i = 1; i < len; ++i) {
switch (mItems[i].pathOp) {
case DESCENDANT_OP:
dest.AppendLiteral("//");
break;
case RELATIVE_OP:
dest.Append(char16_t('/'));
break;
}
mItems[i].expr->toString(dest);
}
}
#endif