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Fix Errors

  • 16.2k installs
  • 148 repo stars
  • Updated July 24, 2026
  • warpdotdev/common-skills

Structured guidance on identifying root causes of compilation, linting, formatting, and test failures; step-by-step commands to isolate and resolve specific error types.

About

This skill diagnoses and fixes compilation errors, clippy linting violations, formatting issues, test failures, and WASM-specific problems in the warp Rust codebase. Developers use it when builds fail, presubmit checks don't pass, or tests break during development. Key workflows include running individual cargo fmt, clippy, and nextest commands; gating WASM-incompatible code behind feature flags; and interpreting common error patterns like type mismatches, unused imports, struct field changes, and enum variant additions. The presubmit script orchestrates all checks at once; specific test filtering and per-package runs target narrow issues.

  • Run unified presubmit checks (fmt, clippy, all tests) via ./script/presubmit before opening PRs
  • Filter and run specific tests by package name or test substring using cargo nextest
  • Gate WASM-incompatible code (filesystem ops, dead code) behind local_fs feature flag with #[cfg] attributes
  • Fix common error types: unused imports, type mismatches, struct field changes, enum variant additions, function signatur
  • Diagnose WASM build failures via cargo clippy --target wasm32-unknown-unknown --profile release-wasm-debug_assertions

Fix Errors by the numbers

  • 16,188 all-time installs (skills.sh)
  • +1,947 installs in the week ending Jul 28, 2026 (Skillselion tracking)
  • Ranked #11 of 610 Debugging skills by installs in the Skillselion catalog
  • Security screen: LOW risk (skills.sh audit)
  • Data as of Jul 28, 2026 (Skillselion catalog sync)
At a glance

fix-errors capabilities & compatibility

Capabilities
diagnose compilation errors · run and filter tests by package or name · validate wasm compatibility · explain error types and fixes · guide presubmit check execution
Use cases
debugging · testing · code review · ci cd
From the docs

What fix-errors says it does

Before opening or updating a pull request, all presubmit checks must pass.
fix-errors overview
npx skills add https://github.com/warpdotdev/common-skills --skill fix-errors

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Listed on Skillselion
Installs16.2k
repo stars148
Security audit3 / 3 scanners passed
Last updatedJuly 24, 2026
Repositorywarpdotdev/common-skills

What it does

Resolve Rust compilation errors, linting failures, and test issues in the warp codebase before submitting pull requests.

Who is it for?

Rust developers on the warp team debugging build failures, test regressions, or linting violations before code review.

Skip if: First-time Rust learners unfamiliar with cargo ecosystem; non-warp codebases with different check scripts.

When should I use this skill?

Build fails, cargo check/clippy/fmt report errors, tests fail, presubmit script blocks PR, WASM compilation errors occur.

What you get

All compilation, linting, formatting, and test checks pass; code is WASM-compatible where required; PR is ready to submit.

  • Passing cargo fmt check
  • Passing cargo clippy check
  • All tests passing

By the numbers

  • Presubmit script covers formatting, linting, and all tests in one command
  • WASM-specific clippy target: wasm32-unknown-unknown with release-wasm-debug_assertions profile
  • Support for filtering tests by substring via cargo nextest -E 'test(<substring>)'

Files

SKILL.mdMarkdownGitHub ↗

fix-errors

Fix compilation errors, linting issues, and test failures in the warp Rust codebase.

Overview

This skill helps resolve common issues encountered during development, including:

  • Compilation errors (unused imports, type mismatches, etc.)
  • Linting failures (clippy warnings)
  • Formatting violations
  • WASM-specific errors
  • Test failures

Before opening or updating a pull request, all presubmit checks must pass.

Presubmit Checks

Run all presubmit checks at once:

./script/presubmit

This runs formatting, linting, and all tests. If it passes, you're ready to open a PR.

Individual Checks

Run checks separately when debugging specific issues:

Rust formatting:

cargo fmt -- --check

Clippy (full workspace):

cargo clippy --workspace --exclude warp_completer --all-targets --all-features --tests -- -D warnings
cargo clippy -p warp_completer --all-targets --tests -- -D warnings

WASM Clippy:

cargo clippy --target wasm32-unknown-unknown --profile release-wasm-debug_assertions --no-deps

Objective-C/C/C++ formatting:

./script/run-clang-format.py -r --extensions 'c,h,cpp,m' ./crates/warpui/src/ ./app/src/

All tests:

cargo nextest run --no-fail-fast --workspace --exclude command-signatures-v2
cargo nextest run -p warp_completer --features v2

Doc tests:

cargo test --doc

Running Specific Tests

Single package:

cargo nextest run -p <package_name>

Filter by test name:

cargo nextest run -E 'test(<substring>)'

Specific package with filter:

cargo nextest run -p <package_name> -E 'test(<substring>)'

With output (no capture):

cargo nextest run -p <package> --nocapture

Common Error Types

Unused Imports

Remove unused use statements identified by the compiler.

Unused Constants

Remove constants that are defined but never used.

Unknown Imports

Add the correct use statement for undefined types. Search the codebase to find the correct module path.

Type Mismatches

Update function calls to pass arguments of the correct type. Common fixes:

  • Use .as_str() instead of .clone() when a &str is expected
  • Use &value when a reference is needed
  • Use .to_string() when String is expected but &str is provided

Struct Field Changes

When a struct adds/removes fields, update all places where it's constructed or destructured:

  • Struct initialization
  • Pattern matching (match, if let)
  • Destructuring assignments

Function Signature Changes

When a function adds a new parameter, update all call sites to provide the new argument:

  • For bool params: pass true or false based on context
  • For Option<T> params: pass None as default or Some(value) if needed

Enum Variant Changes

When adding a new enum variant, update exhaustive match statements:

  • Add a new match arm with appropriate handling
  • Mirror the implementation pattern of similar variants

Incorrect Trait Implementation

Fix trait implementations that return the wrong type or don't satisfy trait bounds.

WASM-Specific Errors

WASM builds (wasm32-unknown-unknown target) don't support filesystem operations. Code that uses filesystem APIs must be gated behind the local_fs feature flag.

Common WASM errors:

  • Dead code warnings for code only used in non-WASM builds
  • Unused code that's only relevant when local_fs is available
  • Tests that require filesystem access

Fixes:

Gate tests behind `local_fs`:

#[test]
#[cfg(feature = "local_fs")]
fn test_find_git_repo_with_worktree() {
    // Test that uses filesystem operations
}

Conditionally allow dead code for types only used when `local_fs` is enabled:

#[cfg_attr(not(feature = "local_fs"), allow(dead_code))]
#[derive(Clone, EnumDiscriminants, Serialize)]
pub enum ExampleType {
    // Variants only used when local_fs is enabled
    Variant1,
    Variant2,
    Variant3,
}

WASM errors are discovered by running:

cargo clippy --target wasm32-unknown-unknown --profile release-wasm-debug_assertions --no-deps

Best Practices

Before fixing:

  • Read the full error message to understand the root cause
  • Check if multiple errors are related (fixing one may resolve others)
  • For trait/type errors, verify you understand the expected vs actual types
  • For WASM errors, check if code needs to be gated behind local_fs

When fixing:

  • Fix one error type at a time when there are multiple issues
  • Run cargo check frequently to verify fixes
  • For WASM errors, run WASM clippy to verify the fix
  • For complex changes, run relevant tests after fixing

After fixing:

  • Always run cargo fmt and cargo clippy before pushing
  • Run the full presubmit script before opening or updating a PR. Use the create-pr skill for more detailed instructions
  • Verify tests pass in the areas you modified

Related skills

How it compares

Pick fix-errors over generic Rust debugging skills when failures occur inside Warp's presubmit, WASM, or monorepo-specific toolchain.

FAQ

How do I run all presubmit checks at once?

Run ./script/presubmit to execute formatting, linting (clippy), and all tests together. If it passes, your code is ready for a PR.

How do I run tests for a specific package?

Use cargo nextest run -p <package_name>, optionally filtering by test name with -E 'test(<substring>'.

What causes WASM build errors and how do I fix them?

WASM (wasm32-unknown-unknown) doesn't support filesystem operations. Gate filesystem code behind #[cfg(feature = "local_fs")] or mark unused code #[cfg_attr(not(feature = "local_fs"), allow(dead_code))].

Is Fix Errors safe to install?

skills.sh reports 3 of 3 security scanners passed. Review the Security Audits panel on this page before installing in production.

Debuggingbackendtesting

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