fix: handle 404 in waitForTaskActive when task is deleted by concurrent run

[johnstcn]

Depends upon #14

Problem: tasks can be deleted due to github action concurrency. Action wasn't handling 404s properly.

Solution:

• Add TaskDeletedError class for explicit error discrimination
• Catch 404 in waitForTaskActive polling loop, throw TaskDeletedError
• Wrap existing-task path in run() with try-catch; on TaskDeletedError, fall through to create a new task
• Tests for both client-level 404 handling and action-level fallthrough

Closes #12

🤖 Created by Coder Agents, reviewed by me.

[Copilot]

Pull request overview

This PR addresses a race condition where a task can be deleted by a concurrent workflow run while waitForTaskActive is polling, causing an unhandled 404 and action failure. It introduces an explicit error type so the action can detect the condition and fall back to creating a new task.

Changes:

• Add TaskDeletedError and throw it from waitForTaskActive when getTaskById returns a 404 during polling.
• Update the existing-task path in CoderTaskAction.run() to catch TaskDeletedError and proceed with creating a new task.
• Add unit tests covering both the client-side 404 handling and the action-level fallback behavior.

Reviewed changes

Copilot reviewed 4 out of 5 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
src/coder-client.ts	Converts polling-time 404s into a dedicated TaskDeletedError for explicit handling.
src/coder-client.test.ts	Adds coverage ensuring polling throws TaskDeletedError when the task disappears mid-loop.
src/action.ts	Catches TaskDeletedError on the existing-task path and falls through to task creation.
src/action.test.ts	Adds a test verifying the action creates a new task when waitForTaskActive fails with TaskDeletedError.
dist/index.js	Updates bundled output to include the new logic (but also includes unrelated bundler-helper changes).

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[mafredri]

Clean fix for the concurrent-deletion race. The error discrimination pattern (dedicated error class, instanceof check, fallthrough) is solid and the tests cover the primary scenario well.

A few things to consider: 2 P3s, 2 nits, 1 observation across 5 inline comments.

🤖 This review was automatically generated with Coder Agents.

[mafredri]

Two additional findings from a late-arriving reviewer that weren't in the first pass.

🤖 This review was automatically generated with Coder Agents.

[johnstcn]

Addressed all review feedback in b7eadbb:

Semantic accuracy (comments 1, 2):

• Renamed TaskDeletedError → TaskNotFoundError with message "Task {id} returned 404 during polling"
• Warning now reads "Lost contact with task '{name}' (404 during polling). Creating a new task."

Robustness (comments 6, 7):

• Catch block in action.ts now also handles CoderAPIError with statusCode === 404 from sendTaskInput
• waitForTaskActive now requires 2 consecutive 404s before throwing (tolerates a single transient 404)

Test coverage (comments 3, 4, 5):

• Fallthrough test now asserts taskUrl contains the new task's ID
• Added test for re-throw branch (CoderAPIError("Request Timeout", 408) propagates, createTask not called)
• Added test for non-404 error propagation in waitForTaskActive (500 → CoderAPIError, not TaskNotFoundError)
• Added test for transient 404 tolerance (single 404 between successful polls → no error)

🤖 This response was generated by Coder Agents.