Code free testing, a testing technique performed without the execution of code. The static testing techniques such as review and static analysis are part of code free testing.
Review - Typically used to find and eliminate errors or ambiguities in documents such as requirements, design, test cases, etc.
Static analysis - The code written by developers are analysed (usually by tools) for structural defects that may lead to defects.
The types of reviews can be given by a simple diagram:
Following are the types of defects found by the tools during static analysis:
A variable with an undefined value
Inconsistent interface between modules and components
Variables that are declared but never used
Unreachable code (or) Dead Code
Programming standards violations
Security vulnerabilities
Syntax violations