A decision-to-decision path, or DD-path, is a path of execution (usually through a flow graph representing a program, such as a flow chart) between two decisions. More recent versions of the concept also include the decisions themselves in their own DD-paths.
In Huang's 1975 paper, [1] a decision-to-decision path is defined as path in a program's flowchart such that all the following hold (quoting from the paper):
Jorgensen's more recent textbooks restate it in terms of a program's flow graph (called a "program graph" in that textbook). [2] First define some preliminary notions: chain and a maximal chain. A chain is defined as a path in which:
A maximal chain is a chain that is not part of a bigger chain.
A DD-path is a set of nodes in a program graph such that one of the following holds (quoting and keeping Jorgensen's numbering, with comments added in parentheses): [2]
According to Jorgensen (2013), in Great Britain and ISTQB literature, the same notion is called linear code sequence and jump (LCSAJ). [2] [ dubious ]
From the latter definition (of Jorgensen) we can conclude the following:
According to Jorgensen's 2013 textbook, DD-path testing is the best known code-based testing method, incorporated in numerous commercial tools. [2]
DD-path testing is also called C2 testing or branch coverage. [3] [4]
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In computer science, a binary decision diagram (BDD) or branching program is a data structure that is used to represent a Boolean function. On a more abstract level, BDDs can be considered as a compressed representation of sets or relations. Unlike other compressed representations, operations are performed directly on the compressed representation, i.e. without decompression.
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Essential complexity is a numerical measure defined by Thomas J. McCabe, Sr., in his highly cited, 1976 paper better known for introducing cyclomatic complexity. McCabe defined essential complexity as the cyclomatic complexity of the reduced CFG after iteratively replacing (reducing) all structured programming control structures, i.e. those having a single entry point and a single exit point with placeholder single statements.
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Requirements traceability is a sub-discipline of requirements management within software development and systems engineering. Traceability as a general term is defined by the IEEE Systems and Software Engineering Vocabulary as (1) the degree to which a relationship can be established between two or more products of the development process, especially products having a predecessor-successor or primary-subordinate relationship to one another; (2) the identification and documentation of derivation paths (upward) and allocation or flowdown paths (downward) of work products in the work product hierarchy; (3) the degree to which each element in a software development product establishes its reason for existing; and (4) discernible association among two or more logical entities, such as requirements, system elements, verifications, or tasks.
Linear code sequence and jump (LCSAJ), in the broad sense, is a software analysis method used to identify structural units in code under test. Its primary use is with dynamic software analysis to help answer the question "How much testing is enough?". Dynamic software analysis is used to measure the quality and efficacy of software test data, where the quantification is performed in terms of structural units of the code under test. When used to quantify the structural units exercised by a given set of test data, dynamic analysis is also referred to as structural coverage analysis.
In graph theory, a well-covered graph is an undirected graph in which the minimal vertex covers all have the same size. Here, a vertex cover is a set of vertices that touches all edges, and it is minimal if removing any vertex from it would leave some edge uncovered. Equivalently, well-covered graphs are the graphs in which all maximal independent sets have equal size. Well-covered graphs were defined and first studied by Michael D. Plummer in 1970.
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Elementary comparison testing (ECT) is a white-box, control-flow, test-design methodology used in software development. The purpose of ECT is to enable detailed testing of complex software. Software code or pseudocode is tested to assess the proper handling of all decision outcomes. As with multiple-condition coverage and basis path testing, coverage of all independent and isolated conditions is accomplished through modified condition/decision coverage (MC/DC). Isolated conditions are aggregated into connected situations creating formal test cases. The independence of a condition is shown by changing the condition value in isolation. Each relevant condition value is covered by test cases.