fix-errors

SKILL.md

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