- We define Declaration Bugs (DCL) as follows:
- An object, a function, a data type, or a namespace is declared or defined improperly.
- Fig. 1 depicts DCL causes, attributes and consequences.
Fig 1. Declaration Bugs (DCL) Class - click on image for detailed view.
-
The DCL operations are: Declare and Define. They reflect the improper declaration or definition of an object, a function, a data type, or a namespace.
| Operation Value | Definition |
|---|---|
| Declare | Specify name and data type of an object; name, return data type, and parameters of a function; or name and type parameters of a data type. |
| Define | Specify data of an object; implementation of a function; or member objects and functions of a data type. |
- The graph of causes shows that there are three main causes for declaration bugs: Improper Operation,
Improper Modifier, Improper Scope and Improper DataType.
- constructor
- +(int,double) overload
- function override in subtype.
- An object is declared int, while it should be float.
- A class implements a cloneable or a serializable interface.
- Comparison via = vs. ==.
- Incorrect data type inference.
- Wrong order or number of arguments to a function call.
- Incorrect deep objects comparison implementation.
| Improper Operation | ||
|---|---|---|
| Value | Definition | Examples |
| Missing | The operation is absent. | Missing:
|
| Wrong | An inappropriate data type is specified; or an inappropriate function/operator is used. | |
| Erroneous | The Type System or a compute function implementation has a bug. | |
| Operands | |
|---|---|
| Concept | Definition |
| Data Value | A numeric, text, pointer/address, or boolean value stored in an object’s memory. |
| Data Type | A set of allowed values and the operations allowed over them. |
| Function | An organized block of code that when called takes in data, processes it, and produces a result(s). |
- The graph of consequences shows Improper Data Type, Improper Function, and Access Errors as consequences.
| Improper Data Type | |
|---|---|
| Concept | Definition |
| Wrong Type | Data type range or structure is not correct. |
| Wrong Type Resolved | Data type is resolved from wrong scope. |
| Wrong Object Resolved Type | Object is resolved from wrong scope,so it’s data type might be wrong. |
| Wrong Sign Type | Unsigned instead of signed data type is specified or vise versa. |
| Wrong Precision Type | Higher precision data type is needed (e.g. double instead of float). |
| Incomplete Type | Specific constructor, method, or overloaded function is missing. |
| Mismatched Argument Type | Argument’s data type is different from function’s parameter data type. |
| Wrong Generic Type | Generic object instantiated via wrong type argument. |
| Confused Subtype | Object invoking an overriden function is of wrong subtype data type. |
| Wrong Argument Type | Argument to an overloaded function is of wrong data type. |
| Improper Function | |
|---|---|
| Concept | Definition |
| Missing Overridden Function | Function implementation in a particular subclass is absent. |
| Missing Overloaded Function | Implementation for particular function parameters’ data types is absent. |
| Wrong Function Resolved | Function is resolved from wrong scope. |
| Wrong Generic Function Bound | Implementation for a wrong data type is bound due to wrong generic type arguments. |
| Wrong Overridden Function Bound | Implementation from wrong subtype is bound due to a wrong invoking subtype object. |
| Wrong Overloaded Function Bound | Wrong overloaded implementation is bound due to wrong function arguments. |
| Access Errors | |
|---|---|
| Value | Definition |
| Wrong Access Object | Unauthorized access to an object exposes sensitive data or allows access to member functions. |
| Wrong Access Type | Unauthorized access to a data type allows access to member objects and functions. |
| Wrong Access Function | Unauthorized access to a function. |
- The attributes of DCL are:
| Name | Value | Definition |
|---|---|---|
| Source Code | Codebase | The operation is in programmer’s code – in the application itself. |
| Third Party | The operation is in a third party library. | |
| Standard Library | The operation is in the standard library for a particular programming language. | |
| Compiler/Interpreter | The operation is in the language processor that allows execution or creates executables (compiler, assembler, interpreter). | |
| Data Type Kind | Primitive | Mimics the hardware units and is not built from other data types – e.g. int (long, short, signed), float, double, string, boolean. |
| Structured | Builds of other data types; have members of primitive and/or structured data types – e.g. array, record, struct, union, class, interface. | |
| Mechanism | Simple | A non-polymorphic entity. |
| Generics | An entity parameterized by type. | |
| Overriding | Functions with the same name as one in the base type, but implemented in different subtypes. | |
| Overloading | Functions with the same name in the same declaration scope, but implemented with different signature. | |
| Entity | Object | A memory region used to store data. |
| Function | An organized block of code that when called takes in data, processes it, and returns a result. | |
| Data Type | A set or a range of values and the operations allowed over them. | |
| Namespace | An organization of entities’ names, utilized to avoid names collision. |
- DCL sites are the entities declarations and definitions.
- Application examples are provided here.