Eliminate redundant zero-capacity slice allocations

[Copilot]

Replace make([]T, 0) with zero-value slice declarations. Zero-value slices work identically with append() and are more idiomatic.

Changes

Pattern:

// Before
result := make([]string, 0)
return &FileTracker{
    CreatedFiles: make([]string, 0),
}

// After
var result []string
return &FileTracker{
    // Field defaults to nil slice
}

Locations (13 instances):

• pkg/cli/mcp_registry.go - 5 instances in runtime/package arg extraction
• pkg/cli/run_push.go - File collection result
• pkg/cli/file_tracker.go - Struct initialization (omitted nil fields)
• pkg/cli/tool_graph.go - Struct initialization (omitted nil field)
• pkg/parser/include_processor.go - Unexpected fields tracking
• pkg/parser/import_processor.go - Topological sort queue
• Test files - 2 mock tracker implementations

Net: 8 files, -9 lines

Original prompt

---

This section details on the original issue you should resolve

<issue_title>[Code Quality] Eliminate redundant zero-capacity slice allocations</issue_title>
<issue_description>## Description

Found 10 instances of explicit make([]T, 0) allocations across the codebase. This pattern is redundant and less idiomatic than zero-value slices in Go.

Current Pattern

envVarNames := make([]string, 0)  // Redundant allocation
for _, name := range vars {
    envVarNames = append(envVarNames, name)
}

Proposed Pattern

var envVarNames []string  // Cleaner, idiomatic Go
for _, name := range vars {
    envVarNames = append(envVarNames, name)
}

Locations to Fix

Production Code (8 instances)

• pkg/workflow/mcp_setup_generator.go:607
• pkg/workflow/jobs.go:48, 432
• pkg/workflow/action_cache.go:241, 242, 279
• pkg/workflow/compiler_safe_outputs_job.go:372
• pkg/workflow/step_order_validation.go:42

Test Code (2 instances)

• Test files (acceptable but can be improved)

Success Criteria

• All 10 instances of make([]T, 0) replaced with zero-value declarations
• All existing tests pass
• Verify with go vet (no warnings)
• Review nil slice behavior matches expectations
• Run golangci-lint to confirm no regressions

Impact

• Severity: Low - Minor code quality improvement
• Effort: Low - Estimated 30 minutes
• Risk: Minimal - Zero-value slices work identically with append
• Benefit: More idiomatic Go code, slightly reduced memory allocations

Why This Matters

1. Idiomatic Go: Zero-value slices are the preferred Go pattern
2. Clarity: More explicit about intentional zero initialization
3. Minor optimization: Eliminates unnecessary allocation syscall
4. Consistency: Aligns with Go best practices

Validation Steps

# Find remaining instances
grep -r "make(\[\].*,\s*0)" pkg/

# Run tests
make test-unit

# Verify with go vet
go vet ./...

# Check with linter
make lint

Source

Extracted from Sergo Report: Memory Allocation & Documentation Quality - 2026-01-27

Priority

Low-Medium - Easy improvement, good for first-time contributors

AI generated by Discussion Task Miner - Code Quality Improvement Agent

• expires on Feb 11, 2026, 9:11 AM UTC

Comments on the Issue (you are @copilot in this section)

• Fixes [Code Quality] Eliminate redundant zero-capacity slice allocations #12224

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