We recently proposed inline tests for validating individual program
statements; they allow developers to provide test inputs, expected
outputs, and test oracles immediately after a target statement. But,
existing code can have many target statements. So, automatic generation of inline tests is an important next step towards increasing
their adoption. We propose ExLi, the first technique for automatically generating inline tests. ExLi extracts inline tests from unit
tests; it first records all variable values at a target statement while
executing unit tests. Then, ExLi uses those values as test inputs
and test oracles in an initial set of generated inline tests. Target
statements that are executed many times could have redundant
initial inline tests. So, ExLi uses a novel coverage-and-mutation
based reduction process to remove redundant inline tests. We implement ExLi for Java and use it to generate inline tests for 718
target statements in 31 open-source programs. ExLi reduces 17,273
initially generated inline tests to 905 inline tests. The final set of
generated inline tests kills up to 25.1% more mutants than developer
written and automatically generated unit tests. That is, ExLi generates inline tests that can improve the fault-detection capability of
the test suites from which they are extracted.
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This content will become publicly available on July 12, 2024
Extracting Inline Tests from Unit Tests
We recently proposed inline tests for validating individual program statements; they allow developers to provide test inputs, expected outputs, and test oracles immediately after a target statement. But, existing code can have many target statements. So, automatic generation of inline tests is an important next step towards increasing their adoption. We propose ExLi, the first technique for automatically generating inline tests. ExLi extracts inline tests from unit tests; it first records all variable values at a target statement while executing unit tests. Then, ExLi uses those values as test inputs and test oracles in an initial set of generated inline tests. Target statements that are executed many times could have redundant initial inline tests. So, ExLi uses a novel coverage-then-mutants based reduction process to remove redundant inline tests. We implement ExLi for Java and use it to generate inline tests for 718 target statements in 31 open-source programs. ExLi reduces 17,273 initially generated inline tests to 905 inline tests. The final set of generated inline tests kills up to 25.1% more mutants on target statements than developer written and automatically generated unit tests. That is, ExLi generates inline tests that can improve the fault-detection capability of the test suites from which they are extracted.
more »
« less
- NSF-PAR ID:
- 10467382
- Publisher / Repository:
- ACM
- Date Published:
- Page Range / eLocation ID:
- 1458 to 1470
- Format(s):
- Medium: X
- Location:
- Seattle WA USA
- Sponsoring Org:
- National Science Foundation
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