perf(core): optimize async operation & progress events

[ido-pluto]

Description of change

Refactor to some core functionality of ipull that improves download speed and make ipull more light wight.

• Replacing pretty-bytes & pretty-ms with an optimize version, that lower the cpu load by ~35% (!!!)
• Optimizing disk writing with queue & debounce to lower the event loop load & context switch ~60% IPull 4.0.3 is heavy on the event loop #19
• Debouncing event at the network file-engine level ~10%
• Cacheing engine CLI calculation ~5%
• --save to directory is hang and saves to current directory #21
• Other bug fixes
• Event order and status flags for Existing (skip existing) and Cloned (file cloned). From now on start and finish events will emit for those edge cases.
• Pause now will close the connections and resume will reopen them.
• Better TypeScript hints for events.

All the performance benchmarks can be found here

https://ido-pluto.github.io/ipull-speed-test/

https://github.com/ido-pluto/ipull-speed-test

Breaking chage:

• '-st' shortcut is not supported yet in the cli, use '--style' instead.
• Some types has been change has I bump deps
• Auto file name functionality has been change to better capture the file name

Pull-Request Checklist

• Code is up-to-date with the main branch
• npm run format to apply eslint formatting
• npm run test passes with this change
• This pull request links relevant issues as Fixes #0000
• There are new or updated unit tests validating the change
• Documentation has been updated to reflect this change
• The new commits follow conventions explained
  in CONTRIBUTING.md

[Copilot]

Pull request overview

This PR focuses on performance and dependency reduction in the download progress/CLI visualization and Node.js write path, while updating CI/build config and tests to match the new behavior.

Changes:

• Replaced pretty-bytes / pretty-ms with new in-repo “fast” formatters and updated CLI/progress rendering to use them.
• Reworked parts of the download engine runtime behavior (write buffering via WriteQueue, progress throttling, metadata-save hook changes, CLI update debouncing/caching).
• Updated test setup (timeouts, fixtures) and CI build pipeline (new tsconfig.prod.json, build:prod, Vitest upgrade).

Reviewed changes

Copilot reviewed 31 out of 32 changed files in this pull request and generated 7 comments.

Show a summary per file

File	Description
vitest.config.ts	Switches to a global test timeout instead of forcing single-thread workers.
tsconfig.prod.json	Adds a production TypeScript build config (used by CI).
test/utils/files.ts	Updates large-file test fixture URL.
test/utils/download.ts	Adjusts local test fixture path/metadata fields.
test/fetchDownloadInfo.test.ts	Updates header string and snapshot formatting; removes per-suite timeout override.
test/download.test.ts	Tweaks chunk size and removes per-suite timeout override.
test/copy-file.test.ts	Removes per-suite timeout override.
test/browser.test.ts	Updates expected hashes; changes concurrency options; skips one browser-memory test.
src/download/transfer-visualize/utils/prettyMSFast.ts	Adds fast compact duration formatting.
src/download/transfer-visualize/utils/prettyBytesFast.ts	Adds fast byte formatting with optional locale/format controls.
src/download/transfer-visualize/transfer-statistics.ts	Avoids divide-by-zero when total bytes is 0.
src/download/transfer-visualize/transfer-cli/transfer-cli.ts	Replaces lodash debounce with manual time-based throttling + SIGINT behavior changes.
src/download/transfer-visualize/transfer-cli/progress-bars/fancy-transfer-cli-progress-bar.ts	Switches duration formatting to the new formatter.
src/download/transfer-visualize/transfer-cli/multiProgressBars/BaseMultiProgressBar.ts	Switches byte formatting to the new formatter.
src/download/transfer-visualize/transfer-cli/GlobalCLI.ts	Adds caching/invalidation for displayed engines; adapts to new updateStatues() API.
src/download/transfer-visualize/progress-statistics-builder.ts	Adds common transfer-action aggregation + cached loading status.
src/download/transfer-visualize/format-transfer-status.ts	Switches formatting helpers to new fast formatters.
src/download/download-engine/streams/download-engine-write-stream/utils/WriteQueue.ts	Introduces buffered coalescing queue for positional writes.
src/download/download-engine/streams/download-engine-write-stream/download-engine-write-stream-nodejs.ts	Integrates WriteQueue, changes metadata flush behavior, adds finalizer-based fd cleanup.
src/download/download-engine/streams/download-engine-fetch-stream/download-engine-fetch-stream-xhr.ts	Cleans abort listener management; switches timeout formatting; adjusts length detection.
src/download/download-engine/streams/download-engine-fetch-stream/download-engine-fetch-stream-fetch.ts	Cleans abort listener lifecycle; switches timeout formatting; adjusts length detection.
src/download/download-engine/streams/download-engine-fetch-stream/base-download-engine-fetch-stream.ts	Adds cloned-listener cleanup to prevent leaks.
src/download/download-engine/engine/download-engine-nodejs.ts	Adapts save-progress hook to new write-stream metadata API.
src/download/download-engine/engine/download-engine-multi-download.ts	Ensures close() happens on error path too.
src/download/download-engine/download-file/progress-status-file.ts	Replaces ProgressStatusFile class usage with EMPTY_PROGRESS_STATUS constant.
src/download/download-engine/download-file/download-engine-file.ts	Reworks progress status creation, adds progress throttling, changes save-progress hook shape.
src/cli/cli.ts	Adjusts save-path interpretation and output naming behavior.
README.md	Improves browser usage docs around CORS/range + manual download info.
package.json	Adds build:prod, upgrades dependencies (Vitest, xmlhttprequest-ssl, semantic-release), removes pretty-* deps.
.github/workflows/test.yml	Uses build:prod in CI.
.github/workflows/build.yml	Uses build:prod in CI; updates release job environment usage.

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[Copilot]

Pull request overview

This PR refactors ipull’s core download/streaming and CLI progress pipeline to reduce event-loop load and CPU usage, while adding a local test server and a broad set of regression tests for range handling, redirects, progress events, and error propagation.

Changes:

• Replace pretty-bytes/pretty-ms + chalk with faster internal formatters and ansis, and reduce CLI update frequency via custom debouncing/caching.
• Optimize disk writes by replacing the previous debounce writer with a coalescing WriteQueue flushed via positional writev.
• Expand test coverage substantially using a new local Express test server with range/no-range/mismatch scenarios.

Reviewed changes

Copilot reviewed 73 out of 75 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
vitest.config.ts	Adjust Vitest worker settings; add longer timeout.
tsconfig.prod.json	Add dedicated production TS build config for CI/build.
test/utils/local-server.ts	New local test server for range/redirect/mismatch scenarios.
test/utils/hash.ts	Switch hashing helper to fs/promises.
test/utils/files.ts	Swap BIG_FILE test URL to a different remote fixture.
test/utils/fetchRangeDownloadParts.ts	Helper to fetch multiple HTTP ranges in parallel.
test/utils/download.ts	Update download test helpers for new part shape/options.
test/redirect-handling.test.ts	New tests for redirect following and URL reuse behavior.
test/range-validation-error.test.ts	New tests for invalid range option validation errors.
test/range-download-parts.test.ts	New test for assembling multiple part URLs into one file.
test/progress-events.test.ts	New test asserting progress/event emissions occur.
test/pause-resume-abort.test.ts	New tests for pause/resume/abort flows not hanging.
test/parallel-streams-edge.test.ts	New edge tests for parallel stream counts and auto-increase.
test/mixed-parts.test.ts	New test mixing range and non-range parts in a single download.
test/fetchstream-error-propagation.test.ts	New test ensuring fetch errors propagate and don’t hang.
test/fetchDownloadInfo.test.ts	Rework fetchDownloadInfo tests to use the local server.
test/eventEmitter.test.ts	New tests for the custom internal EventEmitter.
test/download.test.ts	Update download tests to match new engine options/behavior.
test/daynamic-content-length.test.ts	Update dynamic-length tests to fs/promises cleanup calls.
test/copy-file.test.ts	Update copy tests to fs/promises cleanup calls.
test/content-length-mismatch.test.ts	New tests for invalid/mismatched Content-Length handling.
test/browser.test.ts	Update browser tests and snapshots; adjust concurrency/repeats.
test/accept-range-false.test.ts	New tests for no-range behavior and content-length=0 cases.
src/utils/fs.ts	Add small internal fs helpers (ensureFile/pathExists/readJSON).
src/utils/EventEmitter.ts	New internal EventEmitter implementation with typed overloads.
src/download/transfer-visualize/utils/progressBarIcons.ts	Replace chalk usage with ansis.
src/download/transfer-visualize/utils/prettyMSFast.ts	Add fast compact ms formatter.
src/download/transfer-visualize/utils/prettyBytesFast.ts	Add fast pretty-bytes replacement (number/bigint + options).
src/download/transfer-visualize/transfer-statistics.ts	Fix divide-by-zero percentage when total is 0.
src/download/transfer-visualize/transfer-cli/transfer-cli.ts	Replace lodash debounce with time-gated getter-based update model.
src/download/transfer-visualize/transfer-cli/progress-bars/summary-transfer-cli-progress-bar.ts	Swap chalk → ansis.
src/download/transfer-visualize/transfer-cli/progress-bars/fancy-transfer-cli-progress-bar.ts	Swap chalk/pretty-ms → ansis/prettyMSFast.
src/download/transfer-visualize/transfer-cli/progress-bars/base-transfer-cli-progress-bar.ts	Swap chalk types/colors → ansis; tighten spinner typing.
src/download/transfer-visualize/transfer-cli/multiProgressBars/BaseMultiProgressBar.ts	Swap chalk/pretty-bytes → ansis/prettyBytesFast.
src/download/transfer-visualize/transfer-cli/GlobalCLI.ts	Cache CLI engine/status collection; adapt to new TransferCli updates.
src/download/transfer-visualize/progress-statistics-builder.ts	Switch to internal EventEmitter; optimize transfer-action aggregation/caching.
src/download/transfer-visualize/format-transfer-status.ts	Replace pretty-bytes/pretty-ms with fast formatters; adjust percentage formatting.
src/download/download-engine/utils/sleepPromise.ts	Add internal sleepPromise to replace sleep-promise.
src/download/download-engine/types.ts	Update part shape (remote/download size, range, fetchStream, per-part opts).
src/download/download-engine/streams/download-engine-write-stream/utils/WriteQueue.ts	New buffered coalescing write queue with parallel positional flush.
src/download/download-engine/streams/download-engine-write-stream/utils/BytesWriteDebounce.ts	Remove old debounce writer implementation.
src/download/download-engine/streams/download-engine-write-stream/download-engine-write-stream-nodejs.ts	Integrate WriteQueue + metadata flush; remove fs-extra; add fd lifecycle handling.
src/download/download-engine/streams/download-engine-write-stream/download-engine-write-stream-browser.ts	Add totalLength to writer path; adjust blob creation.
src/download/download-engine/streams/download-engine-write-stream/base-download-engine-write-stream.ts	Update abstract write() signature to include totalLength.
src/download/download-engine/streams/download-engine-fetch-stream/utils/smart-chunk-split.ts	Track saved length incrementally; pass totalLength to write callback.
src/download/download-engine/streams/download-engine-fetch-stream/utils/content-disposition.ts	Trim trailing ; to improve filename parsing resilience.
src/download/download-engine/streams/download-engine-fetch-stream/download-engine-fetch-stream-xhr.ts	Add watchdog-based stream timeout handling; headers timeout abort; content-length validation updates.
src/download/download-engine/streams/download-engine-fetch-stream/download-engine-fetch-stream-local-file.ts	Replace fs-extra ensureFile; adjust locking + async close.
src/download/download-engine/streams/download-engine-fetch-stream/download-engine-fetch-stream-fetch.ts	Add headers timeout abort + watchdog-based throttling; content-length checks; dynamic-length logic adjustments.
src/download/download-engine/streams/download-engine-fetch-stream/base-download-engine-fetch-stream.ts	Replace eventemitter3; add watchdog/timers; add range support; add headers timeout abort utility.
src/download/download-engine/engine/error/missing-event-error.ts	Remove unused error type.
src/download/download-engine/engine/error/invalid-content-length-error.ts	Remove unused engine-level invalid content length error.
src/download/download-engine/engine/error/download-already-started-error.ts	Remove unused error type.
src/download/download-engine/engine/error/RangeOutOfPartLengthError.ts	New error for user-specified range exceeding remote size.
src/download/download-engine/engine/download-engine-nodejs.ts	Adjust save path handling; replace fs-extra; support per-part internal URL objects.
src/download/download-engine/engine/download-engine-multi-download.ts	Switch to internal EventEmitter overload emits; ensure close on error.
src/download/download-engine/engine/download-engine-browser.ts	Support internal full-part URL objects; fetch stream selection changes.
src/download/download-engine/engine/base-download-engine.ts	Add range/full-part URL model; validate ranges; switch to internal EventEmitter overload emits.
src/download/download-engine/engine/DownloadEngineRemote.ts	Switch to internal EventEmitter overload emits.
src/download/download-engine/download-file/progress-status-file.ts	Replace ProgressStatusFile class with EMPTY_PROGRESS_STATUS constant.
src/download/download-engine/download-file/downloaderProgramManager.ts	Switch from sleep-promise to sleepPromise.
src/download/download-engine/download-file/download-programs/switch-program.ts	Pass parallelStreams into program constructors.
src/download/download-engine/download-file/download-programs/download-program-stream.ts	Optimize single-stream case; constructor updated.
src/download/download-engine/download-file/download-programs/download-program-chunks.ts	Constructor updated for explicit parallelStreams.
src/download/download-engine/download-file/download-programs/base-download-program.ts	Store parallelStreams from argument (not saved progress); remove 1-stream early return here.
src/download/download-engine/download-file/download-engine-file.ts	Per-part options (streams/program); new throttled progress; range support; internal emitter overload emits.
src/const.ts	Replace fs-extra readJSON with internal readJSON helper.
src/cli/utils/find-download-dir.ts	Replace fs-extra lstat with fs/promises.
src/cli/cli.ts	Remove -st shorthand; implement directory/file save-path detection; rename connections option parsing.
package.json	Node >=20; add build:prod; remove several deps; bump toolchain/test deps.
README.md	Update browser docs for CORS/range info hints.
.gitignore	Ignore additional test artifacts and downloaded fixtures.
.github/workflows/test.yml	Use npm run build:prod for TS validity.
.github/workflows/build.yml	Use npm run build:prod; adjust release env.

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[Copilot]

Pull request overview

This PR refactors ipull’s core download pipeline to reduce event-loop overhead and improve throughput, including faster formatting helpers, debounced/throttled progress emission, and a new buffered write queue approach, alongside a large suite of new tests and CI build adjustments.

Changes:

• Replace several dependencies/utilities (EventEmitter, fs helpers, pretty-bytes/pretty-ms, chalk→ansis) to reduce CPU and bundle weight.
• Rework download engine internals: per-part options, range support/validation, stream watchdog/timeouts, write buffering/flush behavior.
• Add extensive vitest coverage using a local express server for range/redirect/mismatch/pause/resume edge cases and update CI to build with tsconfig.prod.json.

Reviewed changes

Copilot reviewed 73 out of 75 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
vitest.config.ts	Adjust vitest runtime defaults (timeout; remove forced single-worker config).
tsconfig.prod.json	Add production TypeScript build config used by CI.
test/utils/local-server.ts	New local express test server with range/redirect/mismatch routes.
test/utils/hash.ts	Switch test hashing helper to fs/promises.
test/utils/files.ts	Update large test file URL used by tests.
test/utils/fetchRangeDownloadParts.ts	Add helper to fetch multiple ranged parts in tests.
test/utils/download.ts	Update test download helpers to new engine/part options + internal fs utils.
test/redirect-handling.test.ts	Add redirect reuse behavior tests.
test/range-validation-error.test.ts	Add range validation error tests for browser API.
test/range-download-parts.test.ts	Add multipart ranged download correctness test.
test/progress-events.test.ts	Add progress/event emission sanity test.
test/pause-resume-abort.test.ts	Add pause/resume/abort behavioral tests.
test/parallel-streams-edge.test.ts	Add parallelStreams edge/stress tests.
test/mixed-parts.test.ts	Add mixed accept-range true/false parts test.
test/fetchstream-error-propagation.test.ts	Add fetchStream error propagation / non-hanging test.
test/fetchDownloadInfo.test.ts	Replace external/throttled proxy test with local-server-based test.
test/eventEmitter.test.ts	Add tests for new custom EventEmitter.
test/download.test.ts	Update download tests to new per-part parallel stream configuration.
test/daynamic-content-length.test.ts	Update dynamic content-length tests to fs/promises APIs.
test/copy-file.test.ts	Update copy tests to fs/promises APIs.
test/content-length-mismatch.test.ts	Add tests for invalid Content-Length handling.
test/browser.test.ts	Update browser tests (hash snapshots, repeats config, fs/promises).
test/accept-range-false.test.ts	Add tests for accept-range false / content-length 0 scenarios.
src/utils/fs.ts	New internal fs helpers (ensureFile/pathExists/readJSON).
src/utils/EventEmitter.ts	New internal typed EventEmitter implementation.
src/download/transfer-visualize/utils/progressBarIcons.ts	Switch terminal styling from chalk to ansis.
src/download/transfer-visualize/utils/prettyMSFast.ts	Add faster compact ms formatter.
src/download/transfer-visualize/utils/prettyBytesFast.ts	Add faster bytes formatter with trunc/locale options.
src/download/transfer-visualize/transfer-statistics.ts	Fix percentage calculation for total=0.
src/download/transfer-visualize/transfer-cli/transfer-cli.ts	Replace lodash debounce with time-based throttling + SIGINT handling tweaks.
src/download/transfer-visualize/transfer-cli/progress-bars/summary-transfer-cli-progress-bar.ts	Switch styling from chalk to ansis.
src/download/transfer-visualize/transfer-cli/progress-bars/fancy-transfer-cli-progress-bar.ts	Switch styling + pretty-ms to new fast prettyMS implementation.
src/download/transfer-visualize/transfer-cli/progress-bars/base-transfer-cli-progress-bar.ts	Switch styling from chalk to ansis + SpinnerName typing.
src/download/transfer-visualize/transfer-cli/multiProgressBars/BaseMultiProgressBar.ts	Use prettyBytesFast + ansis; update spinner typing.
src/download/transfer-visualize/transfer-cli/GlobalCLI.ts	Cache CLI engine/status calculation; adjust update flow and finished handling.
src/download/transfer-visualize/progress-statistics-builder.ts	Migrate to internal EventEmitter; cache loading status; compute common transfer action.
src/download/transfer-visualize/format-transfer-status.ts	Use prettyBytesFast/prettyMSFast; adjust percentage formatting.
src/download/download-engine/utils/sleepPromise.ts	Add local sleep helper to replace sleep-promise dependency.
src/download/download-engine/types.ts	Expand part metadata (range, sizes, fetchStream, per-part options).
src/download/download-engine/streams/download-engine-write-stream/utils/WriteQueue.ts	New coalescing write buffer + parallel positional flush design.
src/download/download-engine/streams/download-engine-write-stream/utils/BytesWriteDebounce.ts	Remove previous debounce-based writer implementation.
src/download/download-engine/streams/download-engine-write-stream/download-engine-write-stream-nodejs.ts	Replace fs-extra/debounce writer with WriteQueue + metadata flush integration.
src/download/download-engine/streams/download-engine-write-stream/download-engine-write-stream-browser.ts	Update write signature to include totalLength; tweak Blob typing.
src/download/download-engine/streams/download-engine-write-stream/base-download-engine-write-stream.ts	Update abstract write() signature to include totalLength.
src/download/download-engine/streams/download-engine-fetch-stream/utils/smart-chunk-split.ts	Track savedLength incrementally; pass totalLength into write callback.
src/download/download-engine/streams/download-engine-fetch-stream/utils/content-disposition.ts	Trim trailing ; before parsing Content-Disposition.
src/download/download-engine/streams/download-engine-fetch-stream/download-engine-fetch-stream-xhr.ts	Rework XHR stream watchdog/timeouts + abort handling + totalLength callback.
src/download/download-engine/streams/download-engine-fetch-stream/download-engine-fetch-stream-local-file.ts	Replace fs-extra ensureFile; async close; lock scope change.
src/download/download-engine/streams/download-engine-fetch-stream/download-engine-fetch-stream-fetch.ts	Rework fetch stream to use watchdog/throttling + new abort controller + totalLength callback.
src/download/download-engine/streams/download-engine-fetch-stream/base-download-engine-fetch-stream.ts	Replace eventemitter3/sleep-promise; add range support, watchdog, headersTimeout; update callback signature.
src/download/download-engine/engine/error/missing-event-error.ts	Remove unused/legacy engine error.
src/download/download-engine/engine/error/invalid-content-length-error.ts	Remove legacy engine-level invalid-content-length error.
src/download/download-engine/engine/error/download-already-started-error.ts	Remove unused/legacy error type.
src/download/download-engine/engine/error/RangeOutOfPartLengthError.ts	Add explicit error for user-specified range exceeding remote size.
src/download/download-engine/engine/download-engine-nodejs.ts	Refactor Node engine to new part model; fix savePath directory handling; reflink fast-path updates.
src/download/download-engine/engine/download-engine-multi-download.ts	Migrate to internal EventEmitter and emit0/emit1 usage; adjust error close behavior.
src/download/download-engine/engine/download-engine-browser.ts	Refactor browser engine to new full-part URL model.
src/download/download-engine/engine/base-download-engine.ts	Add range support, full part URL model, range validation, internal EventEmitter.
src/download/download-engine/engine/DownloadEngineRemote.ts	Migrate to internal EventEmitter and emit0/emit1 usage.
src/download/download-engine/download-file/progress-status-file.ts	Replace ProgressStatusFile class with EMPTY_PROGRESS_STATUS object.
src/download/download-engine/download-file/downloaderProgramManager.ts	Replace sleep-promise with local sleepPromise.
src/download/download-engine/download-file/download-programs/switch-program.ts	Pass parallelStreams explicitly into program constructors.
src/download/download-engine/download-file/download-programs/download-program-stream.ts	Add single-stream shortcut in stream program; accept parallelStreams in ctor.
src/download/download-engine/download-file/download-programs/download-program-chunks.ts	Accept parallelStreams in ctor.
src/download/download-engine/download-file/download-programs/base-download-program.ts	Set parallel stream count from passed value (not from saved progress).
src/download/download-engine/download-file/download-engine-file.ts	Major engine refactor: per-part options, new progress model, throttled progress, range size changes.
src/const.ts	Replace fs-extra readJSON with internal readJSON helper.
src/cli/utils/find-download-dir.ts	Replace fs-extra lstat with fs/promises lstat.
src/cli/cli.ts	Fix savePath directory/file detection; remove -st short option; update connections option handling.
package.json	Bump Node engine requirement; add build:prod; update deps (ansis, commander, vitest, etc.).
README.md	Update browser usage docs with CORS/defaultFetchDownloadInfo guidance.
.gitignore	Ignore new/updated test artifacts (big-file.bin, gguf files).
.github/workflows/test.yml	Run TypeScript validity via npm run build:prod.
.github/workflows/build.yml	Use npm run build:prod; adjust release env usage.

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[Copilot]

Pull request overview

This PR refactors ipull’s core download pipeline to reduce event-loop load and improve throughput, including faster formatting utilities, a new write-queue implementation, and broader test coverage via a local HTTP test server.

Changes:

• Replaced/optimized progress formatting and CLI rendering (pretty-bytes/pretty-ms → internal fast versions; chalk → ansis; CLI update debouncing/caching).
• Refactored download engine internals (custom EventEmitter, per-part metadata/range support, fetch-stream throttling/watchdog, write buffering via WriteQueue).
• Expanded and stabilized tests by replacing remote fixtures with a local Express test server and adding new edge-case suites.

Reviewed changes

Copilot reviewed 74 out of 76 changed files in this pull request and generated 7 comments.

Show a summary per file

File	Description
vitest.config.ts	Adjusts vitest runtime settings (timeout) for longer-running integration tests.
tsconfig.prod.json	Adds a prod-focused TS build config used by CI (build:prod).
test/utils/local-server.ts	New local Express server for deterministic range/redirect/content-length scenarios.
test/utils/hash.ts	Switches to fs/promises for hashing helpers.
test/utils/files.ts	Updates large-file fixture URL used in tests.
test/utils/fetchRangeDownloadParts.ts	Adds helper to fetch multiple ranged parts in parallel for tests.
test/utils/download.ts	Updates test download helpers to match new per-part fields and engine options.
test/redirect-handling.test.ts	Adds redirect reuse vs non-reuse behavior tests.
test/range-validation-error.test.ts	Adds validation tests for invalid ranges.
test/range-download-parts.test.ts	Adds multi-part ranged download test and byte-for-byte verification.
test/progress-events.test.ts	Adds event emission/progress smoke coverage.
test/pause-resume-abort.test.ts	Adds pause/resume/abort behavior tests.
test/parallel-streams-edge.test.ts	Adds edge-case tests for high/low parallel stream counts.
test/mixed-parts.test.ts	Adds mixed accept-range parts test.
test/fetchstream-error-propagation.test.ts	Adds test ensuring fetch-stream failures reject instead of hanging.
test/fetchDownloadInfo.test.ts	Refactors to local test server and validates redirected downloads deterministically.
test/eventEmitter.test.ts	Adds unit tests for the new typed EventEmitter implementation.
test/download.test.ts	Updates download tests to new createDownloadFile options and engine behavior.
test/daynamic-content-length.test.ts	Updates file ops to fs/promises and test harness assertions.
test/copy-file.test.ts	Updates file ops to fs/promises and modern vitest assertions.
test/content-length-mismatch.test.ts	Adds mismatch tests for invalid Content-Length handling.
test/browser.test.ts	Updates assertions/fixtures and adjusts concurrency options in browser tests.
test/accept-range-false.test.ts	Adds tests for non-range servers and content-length=0 cases.
src/utils/fs.ts	Introduces lightweight fs helpers replacing fs-extra use cases.
src/utils/EventEmitter.ts	Adds a custom typed EventEmitter with optimized emit paths.
src/download/transfer-visualize/utils/progressBarIcons.ts	Switches coloring library to ansis.
src/download/transfer-visualize/utils/prettyMSFast.ts	Adds optimized compact duration formatting.
src/download/transfer-visualize/utils/prettyBytesFast.ts	Adds optimized byte formatting implementation.
src/download/transfer-visualize/transfer-statistics.ts	Fixes percentage calc for total=0.
src/download/transfer-visualize/transfer-cli/transfer-cli.ts	Refactors CLI update logic to a time-based debounce without lodash.debounce.
src/download/transfer-visualize/transfer-cli/progress-bars/summary-transfer-cli-progress-bar.ts	Switches dim/cyan formatting from chalk to ansis.
src/download/transfer-visualize/transfer-cli/progress-bars/fancy-transfer-cli-progress-bar.ts	Switches chalk→ansis and pretty-ms→prettyMSFast.
src/download/transfer-visualize/transfer-cli/progress-bars/base-transfer-cli-progress-bar.ts	Switches chalk→ansis and updates spinner typing.
src/download/transfer-visualize/transfer-cli/multiProgressBars/BaseMultiProgressBar.ts	Switches chalk→ansis and pretty-bytes→prettyBytesFast.
src/download/transfer-visualize/transfer-cli/GlobalCLI.ts	Adds caching for CLI engine/status selection and refactors progress update flow.
src/download/transfer-visualize/progress-statistics-builder.ts	Switches EventEmitter impl, changes progress emission, and adds “common transfer action” tracking.
src/download/transfer-visualize/format-transfer-status.ts	Switches to fast pretty functions and trunc-based percentage formatting.
src/download/download-engine/utils/sleepPromise.ts	Adds internal sleep helper to remove sleep-promise dependency.
src/download/download-engine/types.ts	Updates per-part schema (remoteFileSize/downloadSize/range/fetchStream).
src/download/download-engine/streams/download-engine-write-stream/utils/WriteQueue.ts	Adds new buffered/merged write queue for fewer syscalls/context switches.
src/download/download-engine/streams/download-engine-write-stream/utils/BytesWriteDebounce.ts	Removes old debounce writer implementation.
src/download/download-engine/streams/download-engine-write-stream/download-engine-write-stream-nodejs.ts	Replaces debounce writer with WriteQueue; refactors metadata flush/write path.
src/download/download-engine/streams/download-engine-write-stream/download-engine-write-stream-browser.ts	Updates write signature (adds totalLength) and Blob creation casting.
src/download/download-engine/streams/download-engine-write-stream/base-download-engine-write-stream.ts	Updates abstract write signature to include totalLength.
src/download/download-engine/streams/download-engine-fetch-stream/utils/smart-chunk-split.ts	Refactors to avoid repeated reduce and to pass totalLength to writer.
src/download/download-engine/streams/download-engine-fetch-stream/utils/content-disposition.ts	Adds trimming for headers ending in ;.
src/download/download-engine/streams/download-engine-fetch-stream/errors/RenewFetchError.ts	Adds internal error for renewing fetch on pause.
src/download/download-engine/streams/download-engine-fetch-stream/download-engine-fetch-stream-xhr.ts	Adds watchdog-based stream responsiveness checks and refactors header/length handling.
src/download/download-engine/streams/download-engine-fetch-stream/download-engine-fetch-stream-local-file.ts	Removes fs-extra ensureFile and adjusts close semantics to async.
src/download/download-engine/streams/download-engine-fetch-stream/download-engine-fetch-stream-fetch.ts	Adds watchdog-based reading/throttling, content-length validation, and abort controller refactor.
src/download/download-engine/streams/download-engine-fetch-stream/base-download-engine-fetch-stream.ts	Switches to custom EventEmitter, adds watchdog/timers, range offsets, and abort controller helper.
src/download/download-engine/engine/error/missing-event-error.ts	Removes unused error type.
src/download/download-engine/engine/error/invalid-content-length-error.ts	Removes unused engine-level error (stream-level remains).
src/download/download-engine/engine/error/download-already-started-error.ts	Removes unused error type.
src/download/download-engine/engine/error/RangeOutOfPartLengthError.ts	Adds explicit error for invalid range end vs remote size.
src/download/download-engine/engine/download-engine-nodejs.ts	Refactors part URL handling (FullPartURL), save-path logic, and reflink clone attempt.
src/download/download-engine/engine/download-engine-multi-download.ts	Switches to custom EventEmitter and adjusts event emission APIs.
src/download/download-engine/engine/download-engine-browser.ts	Refactors part URL handling to FullPartURL and stream selection.
src/download/download-engine/engine/base-download-engine.ts	Adds ranged part support, FullPartURL parsing, and range validation.
src/download/download-engine/engine/DownloadEngineRemote.ts	Switches to custom EventEmitter and emitX APIs.
src/download/download-engine/download-file/progress-status-file.ts	Removes ProgressStatusFile class; adds EMPTY_PROGRESS_STATUS constant.
src/download/download-engine/download-file/downloaderProgramManager.ts	Removes sleep-promise usage in favor of internal sleepPromise.
src/download/download-engine/download-file/download-programs/switch-program.ts	Threads parallelStreams into program creation.
src/download/download-engine/download-file/download-programs/download-program-stream.ts	Adjusts ctor signature and adds explicit single-stream fast path.
src/download/download-engine/download-file/download-programs/download-program-chunks.ts	Adjusts ctor signature to accept parallelStreams.
src/download/download-engine/download-file/download-programs/base-download-program.ts	Uses passed parallelStreams instead of reading from saved progress.
src/download/download-engine/download-file/download-engine-file.ts	Major refactor: per-part options, progress throttling, range sizing, and new stream lifecycle handling.
src/const.ts	Replaces fs-extra JSON read with internal readJSON helper.
src/cli/utils/find-download-dir.ts	Removes fs-extra; uses lstat from fs/promises.
src/cli/cli.ts	Fixes --save directory handling and removes -st shortcut option.
package.json	Updates engine to Node >=20, adds build:prod, updates deps, removes fs-extra/chalk/eventemitter3/etc.
README.md	Updates browser example guidance for CORS + defaultFetchDownloadInfo.
.gitignore	Ignores new test fixtures and generated files.
.github/workflows/test.yml	Switches TS check step to npm run build:prod.
.github/workflows/build.yml	Switches build step to npm run build:prod and adjusts release env.

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[Copilot]

Pull request overview

This PR refactors core download/CLI internals to reduce event-loop overhead and improve throughput (buffered disk writes, progress/event debouncing), while also replacing several dependencies with lighter in-repo utilities and adding a broad new test suite (mostly via a local HTTP test server) to validate edge cases like redirects, ranges, and content-length mismatches.

Changes:

• Replace eventemitter3, pretty-bytes, pretty-ms, chalk with in-repo EventEmitter + pretty*Fast utilities and ansis, updating CLI formatting/output accordingly.
• Rework download pipeline (fetch streams + write streams) to support range-aware offsets, throttled progress emission, and a new high-throughput Node.js WriteQueue.
• Add local-server-based integration tests for redirects/range validation/content-length mismatch and update CI to use build:prod with a new tsconfig.prod.json.

Reviewed changes

Copilot reviewed 74 out of 76 changed files in this pull request and generated 6 comments.

Show a summary per file

File	Description
vitest.config.ts	Adjusts Vitest runtime configuration (now thread pool + explicit timeout).
tsconfig.prod.json	Adds production TS build config used by CI (build:prod).
test/utils/local-server.ts	New local Express server to simulate range/no-range/redirect/mismatch behaviors.
test/utils/hash.ts	Switches hashing utility to fs/promises.
test/utils/files.ts	Changes the large test download URL used by several integration tests.
test/utils/fetchRangeDownloadParts.ts	Adds helper to fetch multiple ranged parts via fetch.
test/utils/download.ts	Updates test download helpers and creates DownloadFile objects with new part fields.
test/redirect-handling.test.ts	Adds redirect reuse behavior tests.
test/range-validation-error.test.ts	Adds range validation error tests.
test/range-download-parts.test.ts	Adds multi-URL range part download test.
test/progress-events.test.ts	Adds event/progress emission coverage for DownloadEngineFile.
test/pause-resume-abort.test.ts	Adds pause/resume/abort behavioral tests.
test/parallel-streams-edge.test.ts	Adds stress/edge tests for parallelStreams behavior.
test/mixed-parts.test.ts	Adds mixed range + non-range parts test.
test/fetchstream-error-propagation.test.ts	Adds regression test to ensure fetch-stream errors don’t hang.
test/fetchDownloadInfo.test.ts	Replaces external throttled proxy test with local-server-based info tests.
test/eventEmitter.test.ts	Adds unit tests for the new in-repo EventEmitter.
test/download.test.ts	Updates download tests to new per-part options and chunk sizing.
test/daynamic-content-length.test.ts	Updates dynamic content-length tests to fs/promises APIs.
test/copy-file.test.ts	Updates copy tests to fs/promises and new helpers.
test/content-length-mismatch.test.ts	Adds explicit content-length mismatch tests (incl. expected error).
test/browser.test.ts	Updates browser tests (new hash snapshot, concurrency config, fs API changes).
test/accept-range-false.test.ts	Adds non-range server behavior tests.
src/utils/fs.ts	Introduces small fs helpers (ensureFile, pathExists, readJSON) to replace fs-extra usage.
src/utils/EventEmitter.ts	Adds new typed EventEmitter implementation with fast-path emits.
src/download/transfer-visualize/utils/progressBarIcons.ts	Switches CLI coloring from chalk to ansis.
src/download/transfer-visualize/utils/prettyMSFast.ts	Adds optimized compact pretty-ms replacement.
src/download/transfer-visualize/utils/prettyBytesFast.ts	Adds optimized pretty-bytes replacement (incl. formatting helpers).
src/download/transfer-visualize/transfer-statistics.ts	Fixes divide-by-zero in percentage calculation when total === 0.
src/download/transfer-visualize/transfer-cli/transfer-cli.ts	Reworks CLI update scheduling (debounce/interval logic, SIGINT behavior).
src/download/transfer-visualize/transfer-cli/progress-bars/summary-transfer-cli-progress-bar.ts	Updates summary progress bar styling to ansis.
src/download/transfer-visualize/transfer-cli/progress-bars/fancy-transfer-cli-progress-bar.ts	Updates fancy progress bar styling + switches to prettyMSFast.
src/download/transfer-visualize/transfer-cli/progress-bars/base-transfer-cli-progress-bar.ts	Updates base progress bar styling/types for ansis + spinner typings.
src/download/transfer-visualize/transfer-cli/multiProgressBars/BaseMultiProgressBar.ts	Uses prettyBytesFast, ansis, and updated spinner types.
src/download/transfer-visualize/transfer-cli/GlobalCLI.ts	Adds caching for CLI engine collection and reworks progress updates via getter.
src/download/transfer-visualize/progress-statistics-builder.ts	Switches to in-repo EventEmitter, tweaks aggregation logic, caches loading status.
src/download/transfer-visualize/format-transfer-status.ts	Switches to pretty*Fast utilities and trunc formatting logic.
src/download/download-engine/utils/sleepPromise.ts	Adds small sleepPromise helper to replace sleep-promise.
src/download/download-engine/types.ts	Updates part shape (remoteFileSize, downloadSize, range, fetchStream) and progress types.
src/download/download-engine/streams/download-engine-write-stream/utils/WriteQueue.ts	Adds new coalescing, adaptive buffering write queue for Node.js write stream.
src/download/download-engine/streams/download-engine-write-stream/utils/BytesWriteDebounce.ts	Removes old debounce-based write aggregator implementation.
src/download/download-engine/streams/download-engine-write-stream/download-engine-write-stream-nodejs.ts	Switches Node writer to WriteQueue, removes fs-extra, adds fd finalization logic.
src/download/download-engine/streams/download-engine-write-stream/download-engine-write-stream-browser.ts	Updates browser writer signature to accept totalLength and adjusts Blob creation typing.
src/download/download-engine/streams/download-engine-write-stream/base-download-engine-write-stream.ts	Updates abstract writer API to include totalLength.
src/download/download-engine/streams/download-engine-fetch-stream/utils/smart-chunk-split.ts	Updates chunk splitting to use downloadSize and tracks saved length incrementally.
src/download/download-engine/streams/download-engine-fetch-stream/utils/content-disposition.ts	Trims trailing ; from header before parsing.
src/download/download-engine/streams/download-engine-fetch-stream/errors/RenewFetchError.ts	Adds internal error used to signal a fetch renewal/retry path.
src/download/download-engine/streams/download-engine-fetch-stream/download-engine-fetch-stream-xhr.ts	Refactors XHR stream logic (timeouts/watchdog/content-length validation/progress).
src/download/download-engine/streams/download-engine-fetch-stream/download-engine-fetch-stream-local-file.ts	Removes fs-extra, uses ensureFile, and makes close async.
src/download/download-engine/streams/download-engine-fetch-stream/download-engine-fetch-stream-fetch.ts	Refactors fetch streaming (watchdog loop, throttling, timeout abort, range handling).
src/download/download-engine/streams/download-engine-fetch-stream/base-download-engine-fetch-stream.ts	Switches to in-repo EventEmitter, adds range offsets, watchdog, and timeout abort controller.
src/download/download-engine/engine/error/missing-event-error.ts	Removes unused engine error.
src/download/download-engine/engine/error/invalid-content-length-error.ts	Removes old engine-layer invalid content-length error.
src/download/download-engine/engine/error/download-already-started-error.ts	Removes unused engine error.
src/download/download-engine/engine/error/RangeOutOfPartLengthError.ts	Adds explicit error for range exceeding remote part size.
src/download/download-engine/engine/download-engine-nodejs.ts	Reworks option parsing to “full part URL” objects, updates progress persistence/clone path.
src/download/download-engine/engine/download-engine-multi-download.ts	Switches to in-repo EventEmitter and fast-path emits; adjusts error/close behavior.
src/download/download-engine/engine/download-engine-browser.ts	Aligns browser engine creation with new “full part URL” internal representation.
src/download/download-engine/engine/base-download-engine.ts	Adds range support and part URL normalization; reworks download-file creation.
src/download/download-engine/engine/DownloadEngineRemote.ts	Switches to in-repo EventEmitter and fast-path emits for remote progress.
src/download/download-engine/download-file/progress-status-file.ts	Replaces class with EMPTY_PROGRESS_STATUS constant; adds Cloned flag.
src/download/download-engine/download-file/downloaderProgramManager.ts	Replaces sleep-promise with sleepPromise.
src/download/download-engine/download-file/download-programs/switch-program.ts	Updates program factory signature to accept parallelStreams.
src/download/download-engine/download-file/download-programs/download-program-stream.ts	Passes parallelStreams into base program; adds fast-path for parallelStreams === 1.
src/download/download-engine/download-file/download-programs/download-program-chunks.ts	Passes parallelStreams into base program.
src/download/download-engine/download-file/download-programs/base-download-program.ts	Uses passed parallelStreams instead of reading from saved progress.
src/download/download-engine/download-file/download-engine-file.ts	Large refactor: per-part options, throttled progress, range offsets, write API change, cloned flag path.
src/const.ts	Replaces fs-extra.readJSON with in-repo readJSON.
src/cli/utils/find-download-dir.ts	Replaces fs-extra.lstat with fs/promises.
src/cli/cli.ts	Updates CLI save-path detection, removes -st shortcut, and adjusts option names.
package.json	Node engine bump, dependency swaps (ansis, remove fs-extra/chalk/pretty-*), adds build:prod.
README.md	Expands browser usage notes for acceptRangeIsKnown / defaultFetchDownloadInfo.
.gitignore	Adds test fixture outputs to ignore list.
.github/workflows/test.yml	Switches TS validity step to npm run build:prod.
.github/workflows/build.yml	Switches build to build:prod and adjusts release environment variables.

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[ido-pluto]

@copilot create me a commit message (do not commit!) for marge, with all the breaking changes - use semantic release syntax

[github-actions]

🎉 This PR is included in version 5.0.0-beta.1 🎉

The release is available on:

• npm package (@beta dist-tag)
• GitHub release
• v5.0.0-beta.1

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