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Partials

A Partial is your C code sliced and diced to expose elements for testing that you could not otherwise access without rewriting your source code. Think of Partials as a unit testing scalpel.

Partials are useful when you need to test:

  • static or inline functions — These become accessible to your test code without modifying your source.
  • File-scoped static variables — The static keyword is stripped, and the variable is automatically made extern for your test code with no changes to the source under test.
  • Function-scoped static variables — These are promoted from function scope to module scope so they can be accessed in your test code just like file-scoped static variables.
  • Same-module mocked functions — You can mix and match tested and mocked functions from the same source module. Partials allow mocking functions inside a module that are called by other functions inside the same module.

Tip

See the wondrous_forest example available within Ceedling for a working example project demonstrating Partials in action.

  • What Is a Partial?

    How Ceedling generates testable and mockable Partials from your C source under test with a step-by-step simple example.

  • Conventions & Terminology

    What is a module? “Public” and “private” functions in a programming language that has no such terminology.

  • Configuration

    How to enable Partials in your project, include ceedling.h, and an overview of directive macro categories.

  • Walk-Through Example

    A complete end-to-end demonstration of Test Partials and Mock Partials.

  • Partial Directive Macros

    • Generation macros used with #include for creating Partials.
    • Config macros for fine-tuning your Partials.

  • Accessing Static Variables

    How to test file-scoped and function-scoped static variables via Partials.

Limitations of Partials

Partials are new to Ceedling with 1.1.0. Carving up C code is tricky business. Complex code may break Ceedling’s lexing or certain assumptions. Some issues may be bugs to be reported while others may be complexities that Partials are simply unable to resolve.