Examples with SwitchBlockStatementExpressionGroupContext org.apache.groovy.parser.antlr4.GroovyLangParser.SwitchBlockStatementExpressionGroupContext used on opensource projects

Example 1 with SwitchBlockStatementExpressionGroupContext

use of org.apache.groovy.parser.antlr4.GroovyLangParser.SwitchBlockStatementExpressionGroupContext in project groovy by apache.

the class AstBuilder method visitSwitchBlockStatementExpressionGroup.

@Override
@SuppressWarnings("unchecked")
public Tuple3<List<Statement>, Boolean, Boolean> visitSwitchBlockStatementExpressionGroup(SwitchBlockStatementExpressionGroupContext ctx) {
    int labelCnt = ctx.switchExpressionLabel().size();
    List<Token> firstLabelHolder = new ArrayList<>(1);
    final int[] arrowCntHolder = new int[1];
    boolean[] isArrowHolder = new boolean[1];
    boolean[] hasResultStmtHolder = new boolean[1];
    List<Statement> result = (List<Statement>) ctx.switchExpressionLabel().stream().map(e -> (Object) this.visitSwitchExpressionLabel(e)).reduce(new ArrayList<Statement>(4), (r, e) -> {
        List<Statement> statementList = (List<Statement>) r;
        Tuple3<Token, List<Expression>, Integer> tuple = (Tuple3<Token, List<Expression>, Integer>) e;
        boolean isArrow = ARROW == tuple.getV3();
        isArrowHolder[0] = isArrow;
        if (isArrow) {
            if (++arrowCntHolder[0] > 1 && !firstLabelHolder.isEmpty()) {
                throw createParsingFailedException("`case ... ->` does not support falling through cases", firstLabelHolder.get(0));
            }
        }
        boolean isLast = labelCnt - 1 == statementList.size();
        BlockStatement codeBlock = this.visitBlockStatements(ctx.blockStatements());
        List<Statement> statements = codeBlock.getStatements();
        int statementsCnt = statements.size();
        if (0 == statementsCnt) {
            throw createParsingFailedException("`yield` is expected", ctx.blockStatements());
        }
        if (isArrow && statementsCnt > 1) {
            throw createParsingFailedException("Expect only 1 statement, but " + statementsCnt + " statements found", ctx.blockStatements());
        }
        if (!isArrow) {
            boolean[] hasYieldHolder = new boolean[1];
            boolean[] hasThrowHolder = new boolean[1];
            codeBlock.visit(new CodeVisitorSupport() {

                @Override
                public void visitReturnStatement(ReturnStatement statement) {
                    if (isTrue(statement, IS_YIELD_STATEMENT)) {
                        hasYieldHolder[0] = true;
                        return;
                    }
                    super.visitReturnStatement(statement);
                }

                @Override
                public void visitThrowStatement(ThrowStatement statement) {
                    hasThrowHolder[0] = true;
                }
            });
            if (hasYieldHolder[0] || hasThrowHolder[0]) {
                hasResultStmtHolder[0] = true;
            }
        }
        Statement exprOrBlockStatement = statements.get(0);
        if (exprOrBlockStatement instanceof BlockStatement) {
            BlockStatement blockStatement = (BlockStatement) exprOrBlockStatement;
            List<Statement> branchStatementList = blockStatement.getStatements();
            if (1 == branchStatementList.size()) {
                exprOrBlockStatement = branchStatementList.get(0);
            }
        }
        if (!(exprOrBlockStatement instanceof ReturnStatement || exprOrBlockStatement instanceof ThrowStatement)) {
            if (isArrow) {
                MethodCallExpression callClosure = callX(configureAST(closureX(null, exprOrBlockStatement), exprOrBlockStatement), "call");
                callClosure.setImplicitThis(false);
                Expression resultExpr = exprOrBlockStatement instanceof ExpressionStatement ? ((ExpressionStatement) exprOrBlockStatement).getExpression() : callClosure;
                codeBlock = configureAST(createBlockStatement(configureAST(returnS(resultExpr), exprOrBlockStatement)), exprOrBlockStatement);
            }
        }
        switch(tuple.getV1().getType()) {
            case CASE:
                {
                    if (!asBoolean(statementList)) {
                        firstLabelHolder.add(tuple.getV1());
                    }
                    for (int i = 0, n = tuple.getV2().size(); i < n; i++) {
                        Expression expr = tuple.getV2().get(i);
                        statementList.add(configureAST(new CaseStatement(expr, // check whether processing the last label. if yes, block statement should be attached.
                        (isLast && i == n - 1) ? codeBlock : EmptyStatement.INSTANCE), firstLabelHolder.get(0)));
                    }
                    break;
                }
            case DEFAULT:
                {
                    codeBlock.putNodeMetaData(IS_SWITCH_DEFAULT, true);
                    statementList.add(// this.configureAST(codeBlock, tuple.getKey())
                    codeBlock);
                    break;
                }
        }
        return statementList;
    });
    return tuple(result, isArrowHolder[0], hasResultStmtHolder[0]);
}