How does Atlas know my Assembly project's test conventions?

Atlas uses its `grep` tool to scan your existing test files, such as `tests/my_module_test.S`, identifying the `make check` framework, import styles, and naming conventions to ensure new tests are consistent.

Can Atlas run my Assembly tests with `make check`?

Yes, Atlas uses its `bash` tool to execute your project's `make check` command, running the Assembly test harness and capturing all output for immediate feedback.

Does Atlas support both `nasm` and GNU Assembler for Assembly testing?

Yes, Atlas is designed to work with your existing `Makefile` and can assemble your Assembly code using either `nasm` or the GNU assembler when running tests via `make check`.

How does Atlas ensure my Assembly code style is consistent?

Atlas integrates with `asmfmt`, your project's Assembly formatter, automatically applying consistent alignment and column styles to any `.asm` or `.S` files it modifies before presenting changes for approval.

What Assembly architectures does Atlas support for unit testing?

Atlas supports unit testing for both x86-64 and ARM64 Assembly architectures, understanding their specific register allocation, calling conventions (System V, AAPCS64), and ABIs.

How does Atlas prevent unwanted changes to my Assembly code?

Atlas employs permission-gated tool calls and presents a unified diff for every proposed change to your `.asm` or `.S` files, requiring your explicit approval before any modifications are written to disk.

Can Atlas help me debug failing Assembly unit tests?

Yes, after running `make check` and identifying failures, Atlas uses its `edit` tool to help you iterate on the test code or the module under test, guiding you to a green test suite.

Write Unit Tests for Untested Assembly Code with Atlas in 2026

In 2026, Assembly developers can efficiently write unit tests for untested code using Atlas, which integrates directly with your existing `make check` test runner and `nasm` toolchain. Atlas reads your Assembly modules, identifies exported symbols, and then generates new test files that adhere to your repository's established conventions, ensuring a smooth workflow for x86-64 and ARM64 architectures.

How Atlas reads Assembly modules and calling conventions for testing

Atlas begins by thoroughly understanding your Assembly codebase, including x86-64 and ARM64 architectures, to ensure accurate test generation. It uses its AST declaration indexing, powered by tree-sitter, to enumerate exported symbols from your `.asm` or `.S` files, identifying every public function. This process ensures that 100% of your module's public interface is considered for testing.

Atlas leverages its `read` tool to ingest your Assembly source files, such as `my_module.asm` or `utility.S`. This initial scan allows Atlas to build a comprehensive index of your code, recognizing sections, labels, and the specific calling conventions each routine honors, whether System V or AAPCS64. Following this, the `lsp` tool's `documentSymbol` operation is employed to enumerate all exported symbols. This critical step ensures that no public function or entry point within the module under test is overlooked, providing a complete scope for unit test coverage. By understanding the ABI and register allocation, Atlas can generate tests that correctly interact with your Assembly routines, respecting the contract of your low-level code. This deep understanding is fundamental before any test code is drafted, ensuring the generated tests are relevant and accurate for your specific Assembly environment.

Generating new Assembly unit tests matching existing `make check` conventions

To maintain consistency, Atlas first identifies your repository's existing Assembly test conventions before writing any new code. It uses the `grep` tool to locate an existing test file, such as `tests/my_existing_test.S`, to learn the framework, import style, and naming conventions. This ensures that the 2026 generated tests direct integrate with your current `make check` setup.

After understanding the module under test, Atlas's next step is to replicate your project's established testing patterns. The `grep` tool is used to search for an existing test file within your repository, for example, `grep -r "TEST_CASE" tests/`. This allows Atlas to analyze the structure, the way includes are handled, the naming of test functions, and the overall framework used by your `make check` harness. Once these conventions are identified, Atlas uses the `write` tool to draft the new spec file, for instance, `tests/new_module_test.asm`. Before this file is written to disk, Atlas presents a unified diff for your approval, allowing you to review the proposed changes and ensure they align with your expectations and the repository's style. This approach prevents the introduction of inconsistent test code and ensures that the new unit tests are immediately compatible with your existing `make check` build system.

Running and debugging Assembly unit tests with `make check` and Atlas

The true validation of any unit test lies in its execution, and Atlas facilitates this by running your new Assembly tests with `make check`. The `bash` tool executes the test suite, capturing all output, even if it exceeds 2000 lines or 50 KB. This immediate feedback loop is crucial for iterating and achieving a green test suite efficiently.

Once the new Assembly test file is drafted, Atlas immediately proceeds to run the test suite using the `bash` tool. This involves executing your project's standard test command, `make check`, which assembles your code with `nasm` or the GNU assembler and runs the test harness. Atlas captures the full output of this execution. If the output is extensive, exceeding 2000 lines or 50 KB, it is truncated in the terminal but the complete log is saved to a file for your detailed review. This direct execution provides immediate feedback on test failures. Atlas then uses the `edit` tool to help you iterate on the test code or the module under test, making necessary adjustments until all tests pass. For larger modules or complex test suites, the `todowrite` tool can be used to manage progress, keeping a clear list of remaining tasks to achieve a fully green test suite. This iterative process, driven by real execution, is central to Atlas's approach to writing robust Assembly unit tests.

Maintaining Assembly code style with `asmfmt` and Atlas

Maintaining consistent code style is vital in Assembly development, and Atlas integrates with `asmfmt` to ensure all touched files adhere to your project's formatting rules. Before any changes are committed, Atlas ensures that alignment and column style are consistent across your `.asm` or `.S` sources. This automated formatting step prevents style drift and saves developers valuable time in 2026.

Atlas understands that code quality extends beyond correctness to include consistent formatting. For Assembly code, this means respecting specific alignment and column styles. Atlas integrates directly with `asmfmt`, your project's designated formatter, to automatically apply these standards to any files it modifies during the test generation and iteration process. Before presenting a final diff for approval, Atlas will invoke `asmfmt` on the newly created test files or any existing Assembly source files that required modifications. This ensures that the generated or altered code direct blends with your existing codebase's aesthetic, preventing formatting inconsistencies. This automated application of `asmfmt` is part of Atlas's commitment to delivering production-ready code, reducing the need for manual style corrections and allowing developers to focus on the logic of their x86-64 or ARM64 Assembly.

Securely reviewing Assembly code changes with Atlas's permission prompts

Atlas prioritizes safety and developer control throughout the entire process of writing Assembly unit tests. Every Atlas tool call, from `read` to `write` to `bash`, is permission-gated against allow, ask, and deny rules. This means you retain full control over what Atlas executes and writes to your `.asm` or `.S` files, with a clear unified diff presented for approval before any changes land on disk in 2026.

Developer control and code integrity are paramount when working with low-level Assembly code. Atlas is designed with multiple layers of safety and review. Before any tool, such as `read`, `lsp`, `grep`, `write`, `bash`, or `edit`, is executed, Atlas consults its permission-gated rules. This allows you to configure Atlas to `allow`, `ask`, or `deny` specific operations, ensuring that no action is taken without your explicit consent. When Atlas proposes to write or modify a file, it computes a unified diff, clearly showing every line added, removed, or changed in your `.asm` or `.S` sources. This diff is surfaced for your approval, providing a transparent overview of the proposed changes before they are committed. Furthermore, Atlas snapshots file changes as git patches, enabling easy diffing and rollback of edits if needed. This robust review mechanism ensures that all modifications to your x86-64 or ARM64 Assembly codebase are intentional and thoroughly vetted by the developer.

Step by step

01Run Atlas in your Assembly project root where `.asm` or `.S` sources and `Makefile` reside.
02Instruct Atlas to `read` the target Assembly module, for example, `my_utility.asm`, and use the `lsp` tool's `documentSymbol` operation to enumerate all exported functions.
03Have Atlas `grep` your repository for an existing test file, like `tests/example_test.S`, to identify the project's `make check` test framework and coding conventions.
04Ask Atlas to `write` a new unit test file, for instance, `tests/my_utility_test.asm`, ensuring it matches the identified conventions. Review the unified diff presented by Atlas for approval.
05Use Atlas's `bash` tool to execute the `make check` command, running the newly generated Assembly unit tests and observing any failures.
06Iterate on the test code or the module under test using Atlas's `edit` tool until all tests pass, leveraging `todowrite` for managing progress on larger modules.
07Confirm Atlas has applied `asmfmt` to all touched `.asm` or `.S` files to maintain consistent alignment and column style.
08Review the final changes and allow Atlas to stage and create a commit for the new, passing Assembly unit tests.

Frequently asked questions

How does Atlas know my Assembly project's test conventions?: Atlas uses its `grep` tool to scan your existing test files, such as `tests/my_module_test.S`, identifying the `make check` framework, import styles, and naming conventions to ensure new tests are consistent.
Can Atlas run my Assembly tests with `make check`?: Yes, Atlas uses its `bash` tool to execute your project's `make check` command, running the Assembly test harness and capturing all output for immediate feedback.
Does Atlas support both `nasm` and GNU Assembler for Assembly testing?: Yes, Atlas is designed to work with your existing `Makefile` and can assemble your Assembly code using either `nasm` or the GNU assembler when running tests via `make check`.
How does Atlas ensure my Assembly code style is consistent?: Atlas integrates with `asmfmt`, your project's Assembly formatter, automatically applying consistent alignment and column styles to any `.asm` or `.S` files it modifies before presenting changes for approval.
What Assembly architectures does Atlas support for unit testing?: Atlas supports unit testing for both x86-64 and ARM64 Assembly architectures, understanding their specific register allocation, calling conventions (System V, AAPCS64), and ABIs.
How does Atlas prevent unwanted changes to my Assembly code?: Atlas employs permission-gated tool calls and presents a unified diff for every proposed change to your `.asm` or `.S` files, requiring your explicit approval before any modifications are written to disk.
Can Atlas help me debug failing Assembly unit tests?: Yes, after running `make check` and identifying failures, Atlas uses its `edit` tool to help you iterate on the test code or the module under test, guiding you to a green test suite.

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