use of com.google.template.soy.soytree.SoyNode.BlockNode in project closure-templates by google.
the class SoyNodeCompiler method visitSwitchNode.
@Override
protected Statement visitSwitchNode(SwitchNode node) {
// A few special cases:
// 1. only a {default} block. In this case we can skip all the switch logic and temporaries
// 2. no children. Just return the empty statement
// Note that in both of these cases we do not evalutate (or generate code) for the switch
// expression.
List<BlockNode> children = node.getChildren();
if (children.isEmpty()) {
return Statement.NULL_STATEMENT;
}
if (children.size() == 1 && children.get(0) instanceof SwitchDefaultNode) {
return visitChildrenInNewScope(children.get(0));
}
// otherwise we need to evaluate the switch variable and generate dispatching logic.
SoyExpression switchVar = exprCompiler.compile(node.getExpr());
Scope scope = variables.enterScope();
Variable variable = scope.createSynthetic(SyntheticVarName.forSwitch(node), switchVar, STORE);
Statement initializer = variable.initializer();
switchVar = switchVar.withSource(variable.local());
List<IfBlock> cases = new ArrayList<>();
Optional<Statement> defaultBlock = Optional.absent();
for (SoyNode child : children) {
if (child instanceof SwitchCaseNode) {
SwitchCaseNode caseNode = (SwitchCaseNode) child;
Label reattachPoint = new Label();
List<Expression> comparisons = new ArrayList<>();
for (ExprRootNode caseExpr : caseNode.getExprList()) {
comparisons.add(compareSoyEquals(switchVar, exprCompiler.compile(caseExpr, reattachPoint)));
}
Expression condition = BytecodeUtils.logicalOr(comparisons).labelStart(reattachPoint);
Statement block = visitChildrenInNewScope(caseNode);
cases.add(IfBlock.create(condition, block));
} else {
SwitchDefaultNode defaultNode = (SwitchDefaultNode) child;
defaultBlock = Optional.of(visitChildrenInNewScope(defaultNode));
}
}
Statement exitScope = scope.exitScope();
// generation that we could maybe use
return Statement.concat(initializer, ControlFlow.ifElseChain(cases, defaultBlock), exitScope);
}
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