wasm_js rustlfags on top workspace #6116

youknowone · 2025-08-31T14:38:19Z

Summary by CodeRabbit

Bug Fixes
- Improved reliability of WebAssembly builds by ensuring a browser-compatible random backend is selected for wasm32 targets, reducing initialization errors in non-WASI WASM environments.
Chores
- Consolidated WASM build configuration at the workspace level for consistent behavior across platforms.
- Added a workspace-level WASM feature and updated package feature mappings to streamline cross-package builds and reduce duplication.

coderabbitai · 2025-08-31T14:38:25Z

Walkthrough

Adds a top-level wasm32 target rustflag, introduces a new wasm_js feature in common/Cargo.toml, removes the duplicate wasm target rustflags from wasm/lib/.cargo/config.toml, and updates the vm crate's wasmbind feature to depend on rustpython-common/wasm_js.

Changes

Cohort / File(s)	Change summary
Top-level Cargo config `/.cargo/config.toml`	Adds `[target.wasm32-unknown-unknown]` with `rustflags = ["--cfg=getrandom_backend=\"wasm_js\""]`.
Common crate features `/common/Cargo.toml`	Adds feature `wasm_js = ["getrandom/wasm_js"]` under `[features]`.
WASM library local config cleanup `/wasm/lib/.cargo/config.toml`	Removes the local `[target.wasm32-unknown-unknown]` `rustflags` entry; keeps `[build] target = "wasm32-unknown-unknown"`.
VM crate feature update `/vm/Cargo.toml`	Updates `wasmbind` feature to include `rustpython-common/wasm_js` in its feature list (replacing direct `getrandom/wasm_js`).

Sequence Diagram(s)

(omitted — changes are configuration-only and do not alter runtime control flow)

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~20 minutes

Poem

I nibble flags beneath the moon,
A tiny hop, a compile tune.
Features stitched and flags set free,
getrandom wanders, safe and merry.
From burrow to the browser sea—hooray for me! 🐇✨

Pre-merge checks and finishing touches

✅ Passed checks (3 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title Check	✅ Passed	The title refers to moving wasm_js rustflags to the top-level workspace, which matches the PR objective and the changeset, but it contains a spelling error ("rustlfags") and awkward phrasing that reduce clarity.
Docstring Coverage	✅ Passed	No functions found in the changes. Docstring coverage check skipped.

✨ Finishing touches

🧪 Generate unit tests

Create PR with unit tests
Post copyable unit tests in a comment

📜 Recent review details

Configuration used: Path: .coderabbit.yml

Review profile: CHILL

Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between 51acf58 and 2e36ff8.

📒 Files selected for processing (2)

common/Cargo.toml (1 hunks)
vm/Cargo.toml (1 hunks)

🚧 Files skipped from review as they are similar to previous changes (2)

vm/Cargo.toml
common/Cargo.toml

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

_{Comment @coderabbitai help to get the list of available commands and usage tips.}

coderabbitai

Actionable comments posted: 0

🧹 Nitpick comments (2)

.cargo/config.toml (1)
7-8: Workspace-level wasm_js cfg looks good; minor quoting/style nit and scope check

Moving the cfg to the top-level target is the right direction. Two nits:

Use single-quoted TOML to avoid inner escapes.

Confirm this broad workspace-level cfg is intended for all crates when building for wasm32-unknown-unknown (it will apply to all members and their deps for that target).

Apply within this hunk:
-[target.wasm32-unknown-unknown]
-rustflags = ["--cfg=getrandom_backend=\"wasm_js\""]
+[target.wasm32-unknown-unknown]
+rustflags = ['--cfg=getrandom_backend="wasm_js"']
common/Cargo.toml (1)
39-41: Double-check getrandom feature name; likely unnecessary/incorrect here

Please verify that getrandom provides a feature literally named "wasm_js". If not, this will fail or be a no-op; the backend selection is already driven by the cfg you added via rustflags. If the cfg is sufficient (it usually is), drop the feature and possibly the whole target-specific dep block to avoid confusion/duplication with the global getrandom dep on Line 22.

Option A — keep the block but remove the feature:
 [target.'cfg(all(target_arch = "wasm32", not(target_os = "wasi")))'.dependencies]
-getrandom = { workspace = true, features = ["wasm_js"] }
+getrandom = { workspace = true }
Option B — remove the redundant block entirely (global dep already exists):
-[target.'cfg(all(target_arch = "wasm32", not(target_os = "wasi")))'.dependencies]
-getrandom = { workspace = true, features = ["wasm_js"] }
Also, if the workspace isn’t on Cargo feature resolver = "2", consider enabling it at the workspace root to prevent unintended feature unification across targets.

📜 Review details

Configuration used: Path: .coderabbit.yml

Review profile: CHILL

Plan: Pro

💡 Knowledge Base configuration:

MCP integration is disabled by default for public repositories
Jira integration is disabled by default for public repositories
Linear integration is disabled by default for public repositories

You can enable these sources in your CodeRabbit configuration.

📥 Commits

Reviewing files that changed from the base of the PR and between 7509387 and fdf5f3e.

📒 Files selected for processing (3)

.cargo/config.toml (1 hunks)
common/Cargo.toml (1 hunks)
wasm/lib/.cargo/config.toml (0 hunks)

💤 Files with no reviewable changes (1)

wasm/lib/.cargo/config.toml

⏰ Context from checks skipped due to timeout of 90000ms. You can increase the timeout in your CodeRabbit configuration to a maximum of 15 minutes (900000ms). (11)

GitHub Check: Run tests under miri
GitHub Check: Run snippets and cpython tests on wasm-wasi
GitHub Check: Check Rust code with rustfmt and clippy
GitHub Check: Check the WASM package and demo
GitHub Check: Run rust tests (windows-latest)
GitHub Check: Run rust tests (macos-latest)
GitHub Check: Run snippets and cpython tests (macos-latest)
GitHub Check: Run rust tests (ubuntu-latest)
GitHub Check: Run snippets and cpython tests (windows-latest)
GitHub Check: Ensure compilation on various targets
GitHub Check: Run snippets and cpython tests (ubuntu-latest)

coolreader18 · 2025-09-01T19:20:34Z

Ah, actually - that test failure is why the config is the way it is. Putting it in the top level means js gets selected even when we're not compiling wasm for browser.

youknowone · 2025-09-02T15:27:15Z

common/Cargo.toml

+[target.'cfg(all(target_arch = "wasm32", not(target_os = "wasi")))'.dependencies]
+getrandom = { workspace = true, features = ["wasm_js"] }
+


Suggested change

[target.'cfg(all(target_arch = "wasm32", not(target_os = "wasi")))'.dependencies]

getrandom = { workspace = true, features = ["wasm_js"] }

This is wrong.

Hmm, true. I guess that should be enabled by a js feature flag that common exposes.

coderabbitai

Actionable comments posted: 3

📜 Review details

Configuration used: Path: .coderabbit.yml

Review profile: CHILL

Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between fdf5f3e and 51acf58.

📒 Files selected for processing (4)

.cargo/config.toml (1 hunks)
common/Cargo.toml (1 hunks)
vm/Cargo.toml (1 hunks)
wasm/lib/.cargo/config.toml (0 hunks)

💤 Files with no reviewable changes (1)

wasm/lib/.cargo/config.toml

🚧 Files skipped from review as they are similar to previous changes (1)

.cargo/config.toml

🧰 Additional context used

🧠 Learnings (1)

📚 Learning: 2025-09-11T05:06:59.971Z

Learnt from: CR
PR: RustPython/RustPython#0
File: .github/copilot-instructions.md:0-0
Timestamp: 2025-09-11T05:06:59.971Z
Learning: Applies to {vm,stdlib}/**/*.rs : Use RustPython macros (`pyclass`, `pymodule`, `pyfunction`, etc.) when implementing Python functionality in Rust

Applied to files:

vm/Cargo.toml

⏰ Context from checks skipped due to timeout of 90000ms. You can increase the timeout in your CodeRabbit configuration to a maximum of 15 minutes (900000ms). (11)

GitHub Check: Run snippets and cpython tests on wasm-wasi
GitHub Check: Run rust tests (windows-2025)
GitHub Check: Check the WASM package and demo
GitHub Check: Run snippets and cpython tests (windows-2025)
GitHub Check: Run snippets and cpython tests (macos-latest)
GitHub Check: Run tests under miri
GitHub Check: Check Rust code with rustfmt and clippy
GitHub Check: Run snippets and cpython tests (ubuntu-latest)
GitHub Check: Run rust tests (macos-latest)
GitHub Check: Run rust tests (ubuntu-latest)
GitHub Check: Ensure compilation on various targets

common/Cargo.toml

coderabbitai · 2025-09-14T08:13:30Z

vm/Cargo.toml

@@ -24,7 +24,7 @@ ast = ["ruff_python_ast", "ruff_text_size"]
 codegen = ["rustpython-codegen", "ast"]
 parser = ["ast"]
 serde = ["dep:serde"]
-wasmbind = ["chrono/wasmbind", "getrandom/wasm_js", "wasm-bindgen"]
+wasmbind = ["rustpython-common/wasm_js", "chrono/wasmbind", "getrandom/wasm_js", "wasm-bindgen"]


🛠️ Refactor suggestion

Avoid double-enabling getrandom’s JS backend; rely on common’s feature only.

wasmbind currently enables both rustpython-common/wasm_js and getrandom/wasm_js. Due to feature unification this is redundant and risks confusion about the single source of truth. Drop the direct getrandom/wasm_js from vm and let common own it.

Apply:

-wasmbind = ["rustpython-common/wasm_js", "chrono/wasmbind", "getrandom/wasm_js", "wasm-bindgen"] +wasmbind = ["rustpython-common/wasm_js", "chrono/wasmbind", "wasm-bindgen"]

📝 Committable suggestion

‼️ IMPORTANT
Carefully review the code before committing. Ensure that it accurately replaces the highlighted code, contains no missing lines, and has no issues with indentation. Thoroughly test & benchmark the code to ensure it meets the requirements.

Suggested change

wasmbind = ["rustpython-common/wasm_js", "chrono/wasmbind", "getrandom/wasm_js", "wasm-bindgen"]

wasmbind = ["rustpython-common/wasm_js", "chrono/wasmbind", "wasm-bindgen"]

🤖 Prompt for AI Agents

In vm/Cargo.toml around line 27, the wasmbind feature list currently includes both "rustpython-common/wasm_js" and "getrandom/wasm_js"; remove "getrandom/wasm_js" from the vm crate's wasmbind feature so the getrandom JS backend is provided only via rustpython-common's wasm_js feature, leaving wasmbind = ["rustpython-common/wasm_js", "chrono/wasmbind", "wasm-bindgen"] (ensure no other references to getrandom/wasm_js remain in this feature).

💡 Verification agent

🧩 Analysis chain

Do not enable browser/wasm bindings by default; this likely caused the test failures.

default = ["compiler", "wasmbind", "stdio"] means native builds also activate wasmbind, which (transitively) opts into the JS randomness backend. Make wasmbind opt‑in only.

Apply:

-default = ["compiler", "wasmbind", "stdio"] +default = ["compiler", "stdio"]

Quick checks:

🏁 Script executed:

#!/bin/bash # 1) Confirm default features no longer include wasmbind rg -nP '^\s*default\s*=\s*\[.*wasmbind' -g 'vm/Cargo.toml' # 2) Ensure no other crate pulls wasmbind by default rg -nP '\bfeatures\b.*wasmbind' -C2 -g '!**/target/**' # 3) Inspect .cargo/config.* to ensure any `--cfg getrandom_backend="wasm_js"` is target-scoped to wasm32 only rg -nP --hidden -C2 'getrandom_backend\s*=\s*"wasm_js"|--cfg\s+getrandom_backend' -g '.cargo/**'

Length of output: 209

Remove wasmbind from default features in vm/Cargo.toml

vm/Cargo.toml:13 currently enables wasmbind in default features, which pulls in the JS getrandom backend for native builds — make wasmbind opt‑in.

Apply:

-default = ["compiler", "wasmbind", "stdio"] +default = ["compiler", "stdio"]

Also ensure any .cargo/config.* or --cfg getrandom_backend="wasm_js" entries are target‑scoped to wasm32 and that no other crate exposes wasmbind in its default features.

Committable suggestion skipped: line range outside the PR's diff.

🤖 Prompt for AI Agents

In vm/Cargo.toml around line 27, remove "wasmbind" from the default features list so the getrandom wasm_js backend is not pulled into native builds; instead add a separate optional feature (e.g., wasmbind) that includes the wasmbind deps and mark those dependencies as optional under that feature so wasm support is opt‑in. Also audit any .cargo/config.* files and Cargo command args and make sure any --cfg getrandom_backend="wasm_js" or equivalent settings are restricted to the wasm32 target (or moved into target."cfg(target_arch = \"wasm32\")" sections), and verify no other crate in the workspace exposes wasmbind in its default-features so the change actually prevents native pulls.

youknowone · 2025-09-14T13:06:36Z

@coolreader18 better?

coderabbitai bot reviewed Aug 31, 2025

View reviewed changes

coolreader18 approved these changes Sep 1, 2025

View reviewed changes

youknowone commented Sep 2, 2025

View reviewed changes

youknowone added 2 commits September 14, 2025 17:07

getrandom/wasm_js for rustpython-common

2e14ba8

wasm_js rustflags on top workspace

5cbb152

youknowone force-pushed the rustflag branch from fdf5f3e to 51acf58 Compare September 14, 2025 08:07

coderabbitai bot reviewed Sep 14, 2025

View reviewed changes

rustpython-common/wasm_js

2e36ff8

youknowone force-pushed the rustflag branch from 51acf58 to 2e36ff8 Compare September 14, 2025 08:22

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Uh oh!

wasm_js rustlfags on top workspace #6116

wasm_js rustlfags on top workspace #6116

Uh oh!

youknowone commented Aug 31, 2025 •

edited by coderabbitai bot

Loading

Uh oh!

coderabbitai bot commented Aug 31, 2025 •

edited

Loading

Uh oh!

coderabbitai bot left a comment

Uh oh!

coolreader18 commented Sep 1, 2025

Uh oh!

youknowone Sep 2, 2025

Uh oh!

coolreader18 Sep 4, 2025

Uh oh!

coderabbitai bot left a comment

Uh oh!

Uh oh!

coderabbitai bot Sep 14, 2025

Uh oh!

youknowone commented Sep 14, 2025

Uh oh!

Uh oh!

		[target.'cfg(all(target_arch = "wasm32", not(target_os = "wasi")))'.dependencies]
		getrandom = { workspace = true, features = ["wasm_js"] }

	wasmbind = ["rustpython-common/wasm_js", "chrono/wasmbind", "getrandom/wasm_js", "wasm-bindgen"]
	wasmbind = ["rustpython-common/wasm_js", "chrono/wasmbind", "wasm-bindgen"]

wasm_js rustlfags on top workspace #6116

Are you sure you want to change the base?

wasm_js rustlfags on top workspace #6116

Uh oh!

Conversation

youknowone commented Aug 31, 2025 • edited by coderabbitai bot Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Summary by CodeRabbit

Uh oh!

coderabbitai bot commented Aug 31, 2025 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Walkthrough

Changes

Sequence Diagram(s)

Estimated code review effort

Poem

Pre-merge checks and finishing touches

Uh oh!

coderabbitai bot left a comment

Choose a reason for hiding this comment

Uh oh!

coolreader18 commented Sep 1, 2025

Uh oh!

youknowone Sep 2, 2025

Choose a reason for hiding this comment

Uh oh!

coolreader18 Sep 4, 2025

Choose a reason for hiding this comment

Uh oh!

coderabbitai bot left a comment

Choose a reason for hiding this comment

Uh oh!

Uh oh!

coderabbitai bot Sep 14, 2025

Choose a reason for hiding this comment

Uh oh!

youknowone commented Sep 14, 2025

Uh oh!

Uh oh!

youknowone commented Aug 31, 2025 •

edited by coderabbitai bot

Loading

coderabbitai bot commented Aug 31, 2025 •

edited

Loading