[Bug]: `--coverage` console report fails on macOS for large suites: `require` of a >2 GiB `coverage.php` hits the 2 GiB single-syscall limit

What happens

On macOS, running a large suite with --coverage — either vendor/bin/pest --coverage or php artisan test --coverage (via nunomaduro/collision) — fails while building the console coverage report:

Cannot write to /.../coverage.php

…and even if the file is produced, reading it back fails symmetrically.

Root cause

The console report round-trips the merged coverage through a var_export'd PHP file and pulls it back with require:

// vendor/pestphp/pest/src/Support/Coverage.php  (mirror in nunomaduro/collision Coverage::report())
$codeCoverage = require $reportPath;   // coverage.php
unlink($reportPath);

For a large suite that coverage.php exceeds 2 GiB, because it serializes the full per-test coverage map (which test touched which line), not just the aggregate. macOS caps a single read()/write() at 2 GiB (EINVAL at ≥ 0x7fffffff bytes), so:

• writing the file (file_put_contents of the var_export string) fails once it crosses 2 GiB, and
• require $reportPath fails the same way — it reads the whole file in one operation.

Crucially, chunking the write into < 2 GiB pieces does not fix it, because the read is an atomic require that can't be chunked. (php-code-coverage 14.x already dropped its own PHP report format, so this var_export/require handoff is now Pest/Collision's own.)

Why the size is avoidable

The same coverage, emitted as a Clover XML report for the same suite, is a few MB. The multi-GB size is purely the per-test granularity of the PHP dump. The console --coverage report only needs aggregate per-file/line coverage — the per-test map is only needed by TIA.

Suggested direction

• For the console-report handoff, serialize aggregate coverage (orders of magnitude smaller) rather than the full per-test map; or
• split the handoff into < 2 GiB chunk files and require/merge each, so no single read/write crosses the macOS limit; or
• hand the report a compact serialization (Clover/XML) instead of a var_export'd PHP file — consistent with php-code-coverage 14.x having removed its PHP format.

TIA's per-test needs (CoverageMerger) can keep their own, chunked serialization independent of the console report.

Workaround (for reference)

We bypass the console report entirely in CI/local: emit --coverage-clover and render a Pest-style per-file "uncovered lines" listing from the XML (a small Artisan command). A few MB, fast, no 2 GiB wall. Happy to share the command if useful.

Environment

• macOS (2 GiB single-syscall read/write limit)
• pestphp/pest 5.0.2, nunomaduro/collision 8.9.5, phpunit/php-code-coverage 14.2.3, PHP 8.5
• Suite: ~10k tests, PCOV coverage; serialized coverage.php > 2 GB

How to Reproduce

1. On macOS, with a suite whose serialized per-test coverage crosses 2 GiB (we hit it around ~10k tests with broad coverage — the coverage.php handoff carries the full per-test map, not just the aggregate).
2. Run vendor/bin/pest --coverage (or php artisan test --coverage).
3. Building the console report fails: Cannot write to /.../coverage.php on the write side, and require $reportPath fails the same way once the file exists.

The trigger is purely file size and independent of the coverage driver (PCOV here): on macOS any valid PHP file ≥ 2 GiB can be neither file_put_contents'd nor required in a single call (EINVAL at ≥ 0x7fffffff bytes), so Coverage::report() breaks the moment coverage.php crosses that line.

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Pest Version

5.0.2

PHP Version

8.5.8

Operation System

macOS

Start with the Coverage.php console-report handoff in Pest and the mirrored Coverage::report() implementation in nunomaduro/collision, focusing on the var_export/file_put_contents and require path described in the issue. Compare the console handoff with the aggregate coverage needs and verify the chosen approach using a macOS suite whose coverage exceeds 2 GiB; done means the console report completes without the single-read/write failure.