Project: fonttools

Language python
OSS-Fuzz project link
Project repository link
Build status: Fuzzers succeeding: Build log
Build status: Code coverage succeeding: Build log
Build status: Fuzz Introspector succeeding: Build log
Fuzzer count 4
Lines of code 6891
Lines covered 1646
Code coverage 23.89%
Code coverage report Report link
Static reachability 2.13%
Fuzz Introspector report Report link (from 2025-07-23)

Historical Progression

Functions of interest to fuzz

This section outlines functions that may be of interest to fuzz. They are based on ranking functions that have a lot of complexity but currently exhibit low code coverage. The complexity is calculated based on the function itself as well as the functions called by the given function, i.e. the tree of code that the function triggers.


This is only a minor amount of introspection information available for this project. Please consult the Fuzz Introspector report for more information, e.g. the introspection table of all functions in the target project available here.

Function name Function source file Accumulated cyclomatic complexity Code coverage
fontTools.varLib.main fontTools.varLib 2422 0.0%
fontTools.varLib.build_many fontTools.varLib 2297 0.0%
fontTools.voltLib.__main__.main fontTools.voltLib.__main__ 2268 0.0%
fontTools.varLib.instancer.main fontTools.varLib.instancer 2090 0.0%
fontTools.varLib.build fontTools.varLib 2039 0.0%
fontTools.varLib.instancer.instantiateVariableFont fontTools.varLib.instancer 1957 0.0%
fontTools.feaLib.__main__.main fontTools.feaLib.__main__ 1887 0.0%
fontTools.fontBuilder.FontBuilder.addOpenTypeFeatures fontTools.fontBuilder 1411 0.0%
fontTools.feaLib.builder.addOpenTypeFeaturesFromString fontTools.feaLib.builder 1408 0.0%
fontTools.feaLib.builder.addOpenTypeFeatures fontTools.feaLib.builder 1402 0.0%