Test: Add edge case coverage and improve diagnostics for strings_test.go

[Copilot]

The test file pkg/workflow/strings_test.go lacked coverage for nil inputs and unicode edge cases, and had generic assertion messages that made failures harder to debug.

Changes

• Nil slice handling: Added TestSortStrings_NilSlice() and TestSortPermissionScopes_NilSlice() to verify Go's sort functions handle nil slices without panics

• Nil options coverage: Added TestSanitizeName_NilOptions() with 7 test cases covering the nil codepath (lines 155-157 in source). Key insight: when opts is nil, special characters are removed completely, not replaced with hyphens:

  SanitizeName("workflow.test.name", nil)  // Returns: "workflowtestname"
  SanitizeName("test_workflow_name", nil) // Returns: "test-workflow-name"

• Unicode truncation: Added 2 test cases to TestShortenCommand() documenting that truncation operates on bytes (20 bytes), not characters:

  ShortenCommand("echo 你好世界 αβγ test")  // Returns: "echo 你好世界 α..." (20 bytes)

• Assertion diagnostics: Updated all assertion messages across 5 test functions to include test case names:

  assert.Equal(t, tt.expected, result, "SortStrings failed for test case: %s", tt.name)

All 464 lines of test code passing. No functional changes to source code.

Original prompt

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This section details on the original issue you should resolve

<issue_title>[testify-expert] Improve Test Quality: pkg/workflow/strings_test.go</issue_title>
<issue_description>## Overview

The test file pkg/workflow/strings_test.go has been selected for quality improvement by the Testify Uber Super Expert. This file demonstrates excellent test structure with comprehensive table-driven tests, but has opportunities for improvement in test coverage and edge case testing.

Current State

• Test File: pkg/workflow/strings_test.go
• Source File: pkg/workflow/strings.go
• Test Functions: 5 test functions
• Lines of Code: 425 lines
• Last Modified: 2026-01-22
• Testify Usage: ✅ Already using testify assertions correctly

Test Quality Analysis

Strengths ✅

1. Excellent table-driven test structure - All tests use proper table-driven patterns with t.Run() and descriptive test case names
2. Good testify assertion usage - Consistently uses assert.Equal() with helpful messages
3. Comprehensive test coverage for main functions - SortStrings, SortPermissionScopes, SanitizeWorkflowName, ShortenCommand, and SanitizeName all have thorough test cases
4. Edge case coverage - Tests include empty strings, single elements, unicode characters, and boundary conditions

Areas for Improvement 🎯

1. Missing Test Coverage for Source Functions

Current State:
The source file strings.go exports 5 functions, but the test file only covers 5 of them. However, there's a critical gap: While SanitizeName is tested extensively, the tests could benefit from testing the function behavior when opts parameter is nil more explicitly.

Coverage Analysis:

• ✅ SortStrings - Well tested (6 test cases)
• ✅ SortPermissionScopes - Well tested (5 test cases)
• ✅ SanitizeWorkflowName - Indirectly tested via SanitizeName tests (15 test cases)
• ✅ ShortenCommand - Well tested (8 test cases)
• ⚠️ SanitizeName - Well tested BUT missing explicit nil options test cases

2. Enhance SanitizeName Testing with Nil Options

Current Issue:
The test file has only 2 test cases that explicitly test nil options behavior (lines 256-267). Given that SanitizeName is the core function that SanitizeWorkflowName depends on, we should ensure nil options are thoroughly tested.

Recommended Test Cases:

func TestSanitizeName_NilOptions(t *testing.T) {
    tests := []struct {
        name     string
        input    string
        expected string
    }{
        {
            name:     "nil options - empty string",
            input:    "",
            expected: "",
        },
        {
            name:     "nil options - only hyphens",
            input:    "---",
            expected: "---", // Hyphens NOT trimmed when opts is nil
        },
        {
            name:     "nil options - leading/trailing hyphens",
            input:    "-workflow-",
            expected: "-workflow-", // Preserved with nil opts
        },
        {
            name:     "nil options - underscores replaced",
            input:    "test_workflow_name",
            expected: "test-workflow-name", // Underscores replaced
        },
        {
            name:     "nil options - dots replaced",
            input:    "workflow.test.name",
            expected: "workflow-test-name", // Dots NOT preserved with nil opts
        },
    }

    for _, tt := range tests {
        t.Run(tt.name, func(t *testing.T) {
            result := SanitizeName(tt.input, nil)
            assert.Equal(t, tt.expected, result, "SanitizeName with nil options should handle edge cases correctly")
        })
    }
}

Why this matters: The function explicitly checks for nil options (line 155 in source), so we should have comprehensive tests for this code path.

3. Add Tests for Empty/Nil Slice Edge Cases

Current Issue:
While both SortStrings and SortPermissionScopes test empty slices, they don't explicitly test nil slices, which is a common edge case in Go.

Recommended Test Cases:

func TestSortStrings_NilSlice(t *testing.T) {
    var nilSlice []string
    
    // Should not panic with nil slice
    SortStrings(nilSlice)
    
    assert.Nil(t, nilSlice, "SortStrings should handle nil slice without panic")
}

func TestSortPermissionScopes_NilSlice(t *testing.T) {
    var nilSlice []PermissionScope
    
    // Should not panic with nil slice
    SortPermissionScopes(nilSlice)
    
    assert.Nil(t, nilSlice, "SortPermissionScopes should handle nil slice without panic")
}

Why this matters: Go's sort.Strings() and sort.Slice() handle nil slices gracefully, but we should explicitly test this behavior to document it and prevent regressions.

4. Test ShortenCommand with Unicode Characters

Current Issue:
The ShortenCommand tests cover most edge cases but don't test behavior with unicode characters, e...

• Fixes [testify-expert] Improve Test Quality: pkg/workflow/strings_test.go #11242

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