Examples with SwitchTree com.sun.source.tree.SwitchTree used on opensource projects

Example 1 with SwitchTree

use of com.sun.source.tree.SwitchTree in project error-prone by google.

the class MissingDefault method matchSwitch.

@Override
public Description matchSwitch(SwitchTree tree, VisitorState state) {
    Type switchType = ASTHelpers.getType(tree.getExpression());
    if (switchType.asElement().getKind() == ElementKind.ENUM) {
        // by MissingCasesInEnumSwitch
        return NO_MATCH;
    }
    Optional<? extends CaseTree> maybeDefault = tree.getCases().stream().filter(c -> c.getExpression() == null).findFirst();
    if (!maybeDefault.isPresent()) {
        Description.Builder description = buildDescription(tree);
        if (!tree.getCases().isEmpty()) {
            // Inserting the default after the last case is easier than finding the closing brace
            // for the switch statement. Hopefully we don't often see switches with zero cases.
            CaseTree lastCase = getLast(tree.getCases());
            String replacement;
            if (lastCase.getStatements().isEmpty() || Reachability.canCompleteNormally(Iterables.getLast(lastCase.getStatements()))) {
                replacement = "\nbreak;\ndefault: // fall out\n";
            } else {
                replacement = "\ndefault: // fall out\n";
            }
            description.addFix(SuggestedFix.postfixWith(getLast(tree.getCases()), replacement));
        }
        return description.build();
    }
    CaseTree defaultCase = maybeDefault.get();
    if (!defaultCase.getStatements().isEmpty()) {
        return NO_MATCH;
    }
    // If `default` case is empty, and last in switch, add `// fall out` comment
    // TODO(epmjohnston): Maybe move comment logic to go/bugpattern/FallThrough
    int idx = tree.getCases().indexOf(defaultCase);
    if (idx != tree.getCases().size() - 1) {
        return NO_MATCH;
    }
    int end = state.getEndPosition(tree);
    if (ErrorProneTokens.getTokens(state.getSourceCode().subSequence(state.getEndPosition(defaultCase), end).toString(), state.context).stream().anyMatch(t -> !t.comments().isEmpty())) {
        return NO_MATCH;
    }
    return buildDescription(defaultCase).setMessage("Default case should be documented with a comment").addFix(SuggestedFix.postfixWith(defaultCase, " // fall out")).build();
}

Example 2 with SwitchTree

use of com.sun.source.tree.SwitchTree in project error-prone by google.

the class SwitchDefault method matchSwitch.

@Override
public Description matchSwitch(SwitchTree tree, VisitorState state) {
    Optional<? extends CaseTree> maybeDefault = tree.getCases().stream().filter(c -> c.getExpression() == null).findAny();
    if (!maybeDefault.isPresent()) {
        return NO_MATCH;
    }
    // Collect all case trees in the statement group containing the default
    List<CaseTree> defaultStatementGroup = new ArrayList<>();
    Iterator<? extends CaseTree> it = tree.getCases().iterator();
    while (it.hasNext()) {
        CaseTree caseTree = it.next();
        defaultStatementGroup.add(caseTree);
        if (caseTree.getExpression() == null) {
            while (it.hasNext() && caseTree.getStatements().isEmpty()) {
                caseTree = it.next();
                defaultStatementGroup.add(caseTree);
            }
            break;
        }
        if (!caseTree.getStatements().isEmpty()) {
            defaultStatementGroup.clear();
        }
    }
    // Find the position of the default case within the statement group
    int idx = defaultStatementGroup.indexOf(maybeDefault.get());
    SuggestedFix.Builder fix = SuggestedFix.builder();
    CaseTree defaultTree = defaultStatementGroup.get(idx);
    if (it.hasNext()) {
        // Only emit a fix if the default doesn't fall through.
        if (!Reachability.canCompleteNormally(getLast(defaultStatementGroup))) {
            int start = ((JCTree) defaultStatementGroup.get(0)).getStartPosition();
            int end = state.getEndPosition(getLast(defaultStatementGroup));
            String replacement;
            String source = state.getSourceCode().toString();
            // If the default case isn't the last case in its statement group, move it to the end.
            if (idx != defaultStatementGroup.size() - 1) {
                int caseEnd = ((JCTree) getLast(defaultStatementGroup).getStatements().get(0)).getStartPosition();
                int cutStart = ((JCTree) defaultTree).getStartPosition();
                int cutEnd = state.getEndPosition(defaultTree);
                replacement = source.substring(start, cutStart) + source.substring(cutEnd, caseEnd) + "\n" + source.substring(cutStart, cutEnd) + source.substring(caseEnd, end);
            } else {
                replacement = source.substring(start, end);
            }
            fix.replace(start, end, "").postfixWith(getLast(tree.getCases()), replacement);
        }
    } else if (idx != defaultStatementGroup.size() - 1) {
        // If the default case isn't the last case in its statement group, move it to the end.
        fix.delete(defaultTree).prefixWith(getLast(defaultStatementGroup).getStatements().get(0), state.getSourceForNode(defaultTree));
    } else {
        return NO_MATCH;
    }
    Description.Builder description = buildDescription(defaultStatementGroup.get(0));
    if (!fix.isEmpty()) {
        description.addFix(fix.build());
    }
    return description.build();
}

Example 3 with SwitchTree

use of com.sun.source.tree.SwitchTree in project st-js by st-js.

the class SwitchWriter method visit.

@Override
public JS visit(WriterVisitor<JS> visitor, SwitchTree tree, GenerationContext<JS> context) {
    Tree expr = tree.getExpression();
    if (expr instanceof ParenthesizedTree) {
        // remove the parans
        expr = ((ParenthesizedTree) expr).getExpression();
    }
    JS jsExpr = visitor.scan(expr, context);
    List<JS> cases = new ArrayList<JS>();
    for (Tree c : tree.getCases()) {
        cases.add(visitor.scan(c, context));
    }
    return context.withPosition(tree, context.js().switchStatement(jsExpr, cases));
}

Example 4 with SwitchTree

use of com.sun.source.tree.SwitchTree in project error-prone by google.

the class MissingCasesInEnumSwitch method matchSwitch.

@Override
public Description matchSwitch(SwitchTree tree, VisitorState state) {
    Type switchType = ASTHelpers.getType(tree.getExpression());
    if (switchType.asElement().getKind() != ElementKind.ENUM) {
        return Description.NO_MATCH;
    }
    // default case is present
    if (tree.getCases().stream().anyMatch(c -> c.getExpression() == null)) {
        return Description.NO_MATCH;
    }
    ImmutableSet<String> handled = tree.getCases().stream().map(CaseTree::getExpression).filter(IdentifierTree.class::isInstance).map(e -> ((IdentifierTree) e).getName().toString()).collect(toImmutableSet());
    Set<String> unhandled = Sets.difference(ASTHelpers.enumValues(switchType.asElement()), handled);
    if (unhandled.isEmpty()) {
        return Description.NO_MATCH;
    }
    return buildDescription(tree).setMessage(buildMessage(unhandled)).build();
}

Example 5 with SwitchTree

use of com.sun.source.tree.SwitchTree in project error-prone by google.

the class UnnecessaryDefaultInEnumSwitch method matchSwitch.

@Override
public Description matchSwitch(SwitchTree tree, VisitorState state) {
    TypeSymbol switchType = ((JCSwitch) tree).getExpression().type.tsym;
    if (switchType.getKind() != ElementKind.ENUM) {
        return NO_MATCH;
    }
    CaseTree caseBeforeDefault = null;
    CaseTree defaultCase = null;
    for (CaseTree caseTree : tree.getCases()) {
        if (caseTree.getExpression() == null) {
            defaultCase = caseTree;
            break;
        } else {
            caseBeforeDefault = caseTree;
        }
    }
    if (defaultCase == null) {
        return NO_MATCH;
    }
    Set<String> handledCases = tree.getCases().stream().map(CaseTree::getExpression).filter(IdentifierTree.class::isInstance).map(p -> ((IdentifierTree) p).getName().toString()).collect(toImmutableSet());
    if (!ASTHelpers.enumValues(switchType).equals(handledCases)) {
        return NO_MATCH;
    }
    Fix fix;
    List<? extends StatementTree> defaultStatements = defaultCase.getStatements();
    if (trivialDefault(defaultStatements)) {
        // deleting `default:` or `default: break;` is a no-op
        fix = SuggestedFix.delete(defaultCase);
    } else {
        String defaultSource = state.getSourceCode().subSequence(((JCTree) defaultStatements.get(0)).getStartPosition(), state.getEndPosition(getLast(defaultStatements))).toString();
        String initialComments = comments(state, defaultCase, defaultStatements);
        if (!canCompleteNormally(tree)) {
            // if the switch statement cannot complete normally, then deleting the default
            // and moving its statements to after the switch statement is a no-op
            fix = SuggestedFix.builder().delete(defaultCase).postfixWith(tree, initialComments + defaultSource).build();
        } else {
            // and the code is unreachable -- so use (2) as the strategy.  Otherwise, use (1).
            if (!SuggestedFixes.compilesWithFix(SuggestedFix.delete(defaultCase), state)) {
                // case (3)
                return NO_MATCH;
            }
            if (!canCompleteNormally(caseBeforeDefault)) {
                // case (2) -- If the case before the default can't complete normally,
                // it's OK to to delete the default.
                fix = SuggestedFix.delete(defaultCase);
            } else {
                // case (1) -- If it can complete, we need to merge the default into it.
                fix = SuggestedFix.builder().delete(defaultCase).postfixWith(caseBeforeDefault, initialComments + defaultSource).build();
            }
        }
    }
    return describeMatch(defaultCase, fix);
}