fix(parser): eliminate Kotlin coroutine bytecode causing ClassNotFoundException in Gradle plugin

[rafaeltonholo]

Summary

• Replace all sequence {} builders in commonMain with explicit stack-based iterators to prevent ClassNotFoundException for kotlin.coroutines.jvm.internal.SpillingKt when running inside Gradle 8.x, which bundles an older Kotlin stdlib (pre-2.1.20)
• Add depthFirstSequence utility for coroutine-free tree traversal, used by listRecursively and deleteRecursivelyCompat
• Refactor deleteRecursivelyCompat from .toList().asReversed() to stack-based post-order traversal, reducing memory usage from O(n) to O(depth) for large directory trees
• Replace sequence {} in applyTransformation with an explicit Iterator to eliminate the last SpillingKt reference
• Remove unused resolveSymlinks/symlinkTarget helpers and followSymlinks parameter

Summary by CodeRabbit

• Refactor
  • Optimized file listing and deletion to use iterative depth-first traversal, with explicit depth limits and no symlink following.
  • Improved behavior when deleting non-existent targets (optional error vs. no-op).
• Tests
  • Added comprehensive tests for listing and recursive deletion, including depth limits, ordering guarantees, laziness, and error cases.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

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📥 Commits

Reviewing files that changed from the base of the PR and between 8d2e99e and 86d78f9.

📒 Files selected for processing (1)

• svg-to-compose/src/commonTest/kotlin/dev/tonholo/s2c/extensions/FileSystemDeleteRecursivelyCompatTest.kt

✅ Files skipped from review due to trivial changes (1)

• svg-to-compose/src/commonTest/kotlin/dev/tonholo/s2c/extensions/FileSystemDeleteRecursivelyCompatTest.kt

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Walkthrough

Introduces a stack-based depth-first traversal utility, rewrites sequence builders to explicit iterators, simplifies listRecursively (removing symlink-following), adds deleteRecursivelyCompat (iterative post-order deletion with existence handling), and adds tests covering traversal and deletion behaviors.

Changes

Cohort / File(s)	Summary
Build Dependencies svg-to-compose/build.gradle.kts	Added libs.com.squareup.okio.fakefilesystem to commonTest for filesystem tests.
Sequence Traversal Utilities svg-to-compose/src/commonMain/kotlin/dev/tonholo/s2c/extensions/LazySequence.kt	Added depthFirstSequence(seeds, childrenOf) with a stack-backed DepthFirstIterator implementing lazy depth-first pre-order traversal (no coroutine sequence builder).
FileSystem Extensions svg-to-compose/src/commonMain/kotlin/dev/tonholo/s2c/extensions/FileSystem.extension.kt	Reworked listRecursively(dir, maxDepth?) to use depthFirstSequence, removed followSymlinks param and symlink-handling; added deleteRecursivelyCompat(fileOrDirectory, mustExist=false) implementing iterative post-order deletion and explicit non-existence handling.
Transform Logic Refactoring svg-to-compose/src/commonMain/kotlin/dev/tonholo/s2c/geom/ApplyTransforms.kt	Replaced coroutine sequence {} implementation with an explicit Sequence { Iterator<...> } iterator for List<PathNodes>.applyTransformation, preserving transformation semantics.
FileManager Integration svg-to-compose/src/commonMain/kotlin/dev/tonholo/s2c/io/FileManager.kt	deleteRecursively now delegates to fileSystem.deleteRecursivelyCompat(...) instead of the previous deleteRecursively call.
Traversal and Deletion Tests svg-to-compose/src/commonTest/kotlin/dev/tonholo/s2c/extensions/FileSystemListRecursivelyTest.kt, .../FileSystemDeleteRecursivelyCompatTest.kt	Added tests validating listRecursively behavior (maxDepth, empty/non-existent dirs, deep trees) and deleteRecursivelyCompat semantics (child-before-parent deletion ordering, streaming vs materialization, mustExist handling).
Sequence Utility Tests svg-to-compose/src/commonTest/kotlin/dev/tonholo/s2c/extensions/LazySequenceTest.kt	Added tests for depthFirstSequence covering empty seeds, flat seeds, tree preorder traversal, and laziness (children callback invoked only as needed).

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~25 minutes

🚥 Pre-merge checks | ✅ 2 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 5.26% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (2 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title accurately summarizes the main change: eliminating Kotlin coroutine bytecode to fix ClassNotFoundException in Gradle plugin, which aligns with the PR's core objective of replacing sequence { } builders with stack-based iterators.

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✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch fix/gradle-classloader-spilling-kt

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[coderabbitai]

Actionable comments posted: 1

🧹 Nitpick comments (1)

svg-to-compose/src/commonTest/kotlin/dev/tonholo/s2c/extensions/FileSystemDeleteRecursivelyCompatTest.kt (1)

34-34: Consider using assertFalse for negated existence checks.

assertTrue(!fs.exists(path)) works but assertFalse(fs.exists(path)) is more idiomatic and produces clearer failure messages.

♻️ Example change

-        assertTrue(!fs.exists(root))
+        assertFalse(fs.exists(root))

Also applies to: 63-63, 74-74, 119-119

🤖 Prompt for AI Agents

Verify each finding against the current code and only fix it if needed.

In
`@svg-to-compose/src/commonTest/kotlin/dev/tonholo/s2c/extensions/FileSystemDeleteRecursivelyCompatTest.kt`
at line 34, Replace negated assertTrue checks with assertFalse for clearer,
idiomatic tests: change assertions like assertTrue(!fs.exists(root)) to
assertFalse(fs.exists(root)), and do the same for the other occurrences using
fs.exists (the instances referenced around the same test file: the assertions at
the other locations that call assertTrue with a negated fs.exists). Ensure you
only swap the assertion call (assertTrue(!...) -> assertFalse(...)) and keep the
fs.exists(...) expression unchanged.

🤖 Prompt for all review comments with AI agents

Verify each finding against the current code and only fix it if needed.

Inline comments:
In
`@svg-to-compose/src/commonTest/kotlin/dev/tonholo/s2c/extensions/FileSystemDeleteRecursivelyCompatTest.kt`:
- Around line 122-126: The assertEquals call in
FileSystemDeleteRecursivelyCompatTest has its expected and actual arguments
reversed; change the parameters so expected = expectedDeletions and actual =
recorder.deletedPaths.size (i.e., swap them in the assertEquals invocation) to
ensure failure messages report the expected value correctly and reference the
correct symbols (recorder.deletedPaths.size and expectedDeletions) when updating
the test.

---

Nitpick comments:
In
`@svg-to-compose/src/commonTest/kotlin/dev/tonholo/s2c/extensions/FileSystemDeleteRecursivelyCompatTest.kt`:
- Line 34: Replace negated assertTrue checks with assertFalse for clearer,
idiomatic tests: change assertions like assertTrue(!fs.exists(root)) to
assertFalse(fs.exists(root)), and do the same for the other occurrences using
fs.exists (the instances referenced around the same test file: the assertions at
the other locations that call assertTrue with a negated fs.exists). Ensure you
only swap the assertion call (assertTrue(!...) -> assertFalse(...)) and keep the
fs.exists(...) expression unchanged.

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: Path: .coderabbit.yaml

Review profile: CHILL

Plan: Pro

Run ID: 466cb1cf-b6a9-40a5-919c-d8509d2d4281

📥 Commits

Reviewing files that changed from the base of the PR and between 1167695 and 8d2e99e.

📒 Files selected for processing (8)

• svg-to-compose/build.gradle.kts
• svg-to-compose/src/commonMain/kotlin/dev/tonholo/s2c/extensions/FileSystem.extension.kt
• svg-to-compose/src/commonMain/kotlin/dev/tonholo/s2c/extensions/LazySequence.kt
• svg-to-compose/src/commonMain/kotlin/dev/tonholo/s2c/geom/ApplyTransforms.kt
• svg-to-compose/src/commonMain/kotlin/dev/tonholo/s2c/io/FileManager.kt
• svg-to-compose/src/commonTest/kotlin/dev/tonholo/s2c/extensions/FileSystemDeleteRecursivelyCompatTest.kt
• svg-to-compose/src/commonTest/kotlin/dev/tonholo/s2c/extensions/FileSystemListRecursivelyTest.kt
• svg-to-compose/src/commonTest/kotlin/dev/tonholo/s2c/extensions/LazySequenceTest.kt