Examples with METHOD_INVOCATION com.sun.source.tree.Tree.Kind.METHOD_INVOCATION used on opensource projects

Example 1 with METHOD_INVOCATION

use of com.sun.source.tree.Tree.Kind.METHOD_INVOCATION 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.
 *
 * <p>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.)
 *
 * <p>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.
 *
 * <p>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.
 *
 * <p>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 = stripNullCheck(rhs, state);
    }
    ImmutableList<Fix> exploratoryFieldFixes = ImmutableList.of();
    if (lhs.getKind() == MEMBER_SELECT) {
        // find a method parameter of the same type and similar name and suggest it
        // as the rhs
        // rhs should be either identifier or field access
        Preconditions.checkState(rhs.getKind() == IDENTIFIER || rhs.getKind() == MEMBER_SELECT);
        Type rhsType = ASTHelpers.getType(rhs);
        exploratoryFieldFixes = ReplacementVariableFinder.fixesByReplacingExpressionWithMethodParameter(rhs, varDecl -> ASTHelpers.isSameType(rhsType, varDecl.type, state), state);
    } else if (rhs.getKind() == IDENTIFIER) {
        // find a field of the same type and similar name and suggest it as the lhs
        // lhs should be identifier
        Preconditions.checkState(lhs.getKind() == IDENTIFIER);
        Type lhsType = ASTHelpers.getType(lhs);
        exploratoryFieldFixes = ReplacementVariableFinder.fixesByReplacingExpressionWithLocallyDeclaredField(lhs, var -> !Flags.isStatic(var.sym) && (var.sym.flags() & Flags.FINAL) == 0 && ASTHelpers.isSameType(lhsType, var.type, state), state);
    }
    if (exploratoryFieldFixes.isEmpty()) {
        return describeMatch(assignmentTree, fix);
    }
    return buildDescription(assignmentTree).addAllFixes(exploratoryFieldFixes).build();
}