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

Example 46 with ExpressionTree

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

the class ASTHelpers method sameVariable.

/**
   * Determines whether two expressions refer to the same variable. Note that returning false
   * doesn't necessarily mean the expressions do *not* refer to the same field. We don't attempt
   * to do any complex analysis here, just catch the obvious cases.
   */
public static boolean sameVariable(ExpressionTree expr1, ExpressionTree expr2) {
    // Throw up our hands if we're not comparing identifiers and/or field accesses.
    if ((expr1.getKind() != Kind.IDENTIFIER && expr1.getKind() != Kind.MEMBER_SELECT) || (expr2.getKind() != Kind.IDENTIFIER && expr2.getKind() != Kind.MEMBER_SELECT)) {
        return false;
    }
    Symbol sym1 = getSymbol(expr1);
    Symbol sym2 = getSymbol(expr2);
    if (sym1 == null) {
        throw new IllegalStateException("Couldn't get symbol for " + expr1);
    } else if (sym2 == null) {
        throw new IllegalStateException("Couldn't get symbol for " + expr2);
    }
    if (expr1.getKind() == Kind.IDENTIFIER && expr2.getKind() == Kind.IDENTIFIER) {
        // foo == foo?
        return sym1.equals(sym2);
    } else if (expr1.getKind() == Kind.MEMBER_SELECT && expr2.getKind() == Kind.MEMBER_SELECT) {
        // foo.baz.bar == foo.baz.bar?
        return sym1.equals(sym2) && sameVariable(((JCFieldAccess) expr1).selected, ((JCFieldAccess) expr2).selected);
    } else {
        // this.foo == foo?
        ExpressionTree selected = null;
        if (expr1.getKind() == Kind.IDENTIFIER) {
            selected = ((JCFieldAccess) expr2).selected;
        } else {
            selected = ((JCFieldAccess) expr1).selected;
        }
        // TODO(eaftan): really shouldn't be relying on .toString()
        return selected.toString().equals("this") && sym1.equals(sym2);
    }
}

Example 47 with ExpressionTree

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

the class Matchers method receiverSameAsArgument.

/**
   * Matches when the receiver of an instance method is the same reference as a particular argument to the method.
   * For example, receiverSameAsArgument(1) would match {@code obj.method("", obj)}
   *
   * @param argNum The number of the argument to compare against (zero-based.
   */
public static Matcher<? super MethodInvocationTree> receiverSameAsArgument(final int argNum) {
    return new Matcher<MethodInvocationTree>() {

        @Override
        public boolean matches(MethodInvocationTree t, VisitorState state) {
            List<? extends ExpressionTree> args = t.getArguments();
            if (args.size() <= argNum) {
                return false;
            }
            ExpressionTree arg = args.get(argNum);
            JCExpression methodSelect = (JCExpression) t.getMethodSelect();
            if (methodSelect instanceof JCFieldAccess) {
                JCFieldAccess fieldAccess = (JCFieldAccess) methodSelect;
                return ASTHelpers.sameVariable(fieldAccess.getExpression(), arg);
            } else if (methodSelect instanceof JCIdent) {
                // A bare method call: "equals(foo)".  Receiver is implicitly "this".
                return "this".equals(arg.toString());
            }
            return false;
        }
    };
}

Example 48 with ExpressionTree

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

the class IsLoggableTagLength method matchMethodInvocation.

@Override
public Description matchMethodInvocation(MethodInvocationTree tree, VisitorState state) {
    if (!IS_LOGGABLE_CALL.matches(tree, state)) {
        return NO_MATCH;
    }
    ExpressionTree tagArg = tree.getArguments().get(0);
    // Check for constant value.
    String tagConstantValue = ASTHelpers.constValue(tagArg, String.class);
    if (tagConstantValue != null) {
        return isValidTag(tagConstantValue) ? NO_MATCH : describeMatch(tagArg);
    }
    // Check for class literal simple name (e.g. MyClass.class.getSimpleName().
    ExpressionTree tagExpr = tagArg;
    // If the tag argument is a final field, retrieve the initializer.
    if (kindIs(IDENTIFIER).matches(tagArg, state)) {
        VariableTree declaredField = findEnclosingIdentifier((IdentifierTree) tagArg, state);
        if (declaredField == null || !hasModifier(FINAL).matches(declaredField, state)) {
            return NO_MATCH;
        }
        tagExpr = declaredField.getInitializer();
    }
    if (GET_SIMPLE_NAME_CALL.matches(tagExpr, state) && RECEIVER_IS_CLASS_LITERAL.matches((MethodInvocationTree) tagExpr, state)) {
        String tagName = getSymbol(getReceiver(getReceiver(tagExpr))).getSimpleName().toString();
        return isValidTag(tagName) ? NO_MATCH : describeMatch(tagArg);
    }
    return NO_MATCH;
}

Example 49 with ExpressionTree

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

the class SelfAssignment method describeForAssignment.

/**
   * We expect that the lhs is a field and the rhs is an identifier, specifically
   * a parameter to the method.  We base our suggested fixes on this expectation.
   *
   * Case 1: If lhs is a field and rhs is an identifier, find a method parameter
   * of the same type and similar name and suggest it as the rhs.  (Guess that they
   * have misspelled the identifier.)
   *
   * Case 2: If lhs is a field and rhs is not an identifier, find a method parameter
   * of the same type and similar name and suggest it as the rhs.
   *
   * Case 3: If lhs is not a field and rhs is an identifier, find a class field
   * of the same type and similar name and suggest it as the lhs.
   *
   * Case 4: Otherwise suggest deleting the assignment.
   */
public Description describeForAssignment(AssignmentTree assignmentTree, VisitorState state) {
    // the statement that is the parent of the self-assignment expression
    Tree parent = state.getPath().getParentPath().getLeaf();
    // default fix is to delete assignment
    Fix fix = SuggestedFix.delete(parent);
    ExpressionTree lhs = assignmentTree.getVariable();
    ExpressionTree rhs = assignmentTree.getExpression();
    // if this is a method invocation, they must be calling checkNotNull()
    if (assignmentTree.getExpression().getKind() == METHOD_INVOCATION) {
        // change the default fix to be "checkNotNull(x)" instead of "x = checkNotNull(x)"
        fix = SuggestedFix.replace(assignmentTree, rhs.toString());
        // new rhs is first argument to checkNotNull()
        rhs = stripCheckNotNull(rhs, state);
    }
    if (lhs.getKind() == MEMBER_SELECT) {
        // rhs should be either identifier or field access
        assert (rhs.getKind() == IDENTIFIER || rhs.getKind() == MEMBER_SELECT);
        // get current name of rhs
        String rhsName = null;
        if (rhs.getKind() == IDENTIFIER) {
            rhsName = ((JCIdent) rhs).name.toString();
        } else if (rhs.getKind() == MEMBER_SELECT) {
            rhsName = ((JCFieldAccess) rhs).name.toString();
        }
        // find method parameters of the same type
        Type type = ((JCFieldAccess) lhs).type;
        TreePath path = state.getPath();
        while (path != null && path.getLeaf().getKind() != METHOD) {
            path = path.getParentPath();
        }
        JCMethodDecl method = (JCMethodDecl) path.getLeaf();
        int minEditDistance = Integer.MAX_VALUE;
        String replacement = null;
        for (JCVariableDecl var : method.params) {
            if (var.type == type) {
                int editDistance = EditDistance.getEditDistance(rhsName, var.name.toString());
                if (editDistance < minEditDistance) {
                    // pick one with minimum edit distance
                    minEditDistance = editDistance;
                    replacement = var.name.toString();
                }
            }
        }
        if (replacement != null) {
            // suggest replacing rhs with the parameter
            fix = SuggestedFix.replace(rhs, replacement);
        }
    } else if (rhs.getKind() == IDENTIFIER) {
        // lhs should be identifier
        assert (lhs.getKind() == IDENTIFIER);
        // get current name of lhs
        String lhsName = ((JCIdent) rhs).name.toString();
        // find class instance fields of the same type
        Type type = ((JCIdent) lhs).type;
        TreePath path = state.getPath();
        while (path != null && !(path.getLeaf() instanceof JCClassDecl)) {
            path = path.getParentPath();
        }
        if (path == null) {
            throw new IllegalStateException("Expected to find an enclosing class declaration");
        }
        JCClassDecl klass = (JCClassDecl) path.getLeaf();
        int minEditDistance = Integer.MAX_VALUE;
        String replacement = null;
        for (JCTree member : klass.getMembers()) {
            if (member.getKind() == VARIABLE) {
                JCVariableDecl var = (JCVariableDecl) member;
                if (!Flags.isStatic(var.sym) && var.type == type) {
                    int editDistance = EditDistance.getEditDistance(lhsName, var.name.toString());
                    if (editDistance < minEditDistance) {
                        // pick one with minimum edit distance
                        minEditDistance = editDistance;
                        replacement = var.name.toString();
                    }
                }
            }
        }
        if (replacement != null) {
            // suggest replacing lhs with the field
            fix = SuggestedFix.replace(lhs, "this." + replacement);
        }
    }
    return describeMatch(assignmentTree, fix);
}

Example 50 with ExpressionTree

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

the class IncompatibleArgumentType method reportAnyViolations.

private void reportAnyViolations(List<? extends ExpressionTree> arguments, List<RequiredType> requiredTypesAtCallSite, VisitorState state) {
    Types types = state.getTypes();
    for (int i = 0; i < requiredTypesAtCallSite.size(); i++) {
        RequiredType requiredType = requiredTypesAtCallSite.get(i);
        if (requiredType == null) {
            continue;
        }
        ExpressionTree argument = arguments.get(i);
        Type argType = ASTHelpers.getType(argument);
        if (requiredType.type() != null && !types.isCastable(argType, types.erasure(ASTHelpers.getUpperBound(requiredType.type(), types)))) {
            // Report a violation for this type
            state.reportMatch(describeViolation(argument, argType, requiredType.type(), types));
        }
    }
}