test(auth): Increase auth test coverage from 6% to 80% with mock provider

[Erik Osterman (Cloud Posse) (osterman)]

what

• Add comprehensive unit and integration tests for Atmos auth system using the existing mock provider
• Increase test coverage from 6% to ~80% (target: 80-90% ✅)
• Add regression tests to prevent recurrence of user-reported browser authentication issue
• Achieve 100% coverage for mock provider implementation

why

• Current auth test coverage was critically low (6%), making it difficult to catch bugs
• User complaint (Bogdan) about browser authentication triggering on every command needed verification and regression protection
• Mock provider was implemented but had zero test coverage
• Need confidence that auth system works correctly without requiring real cloud credentials

Coverage Improvements

Package	Before	After	Improvement
pkg/auth	6.2%	84.6%	+78.4pp
pkg/auth/providers/mock	0%	100.0%	+100pp
pkg/auth/utils	0%	100.0%	+100pp
pkg/auth/validation	0%	90.0%	+90pp
pkg/auth/list	0%	89.5%	+89.5pp
pkg/auth/cloud/aws	0%	79.2%	+79.2pp
pkg/auth/providers/github	0%	78.3%	+78.3pp
pkg/auth/factory	0%	77.8%	+77.8pp
pkg/auth/credentials	0%	75.8%	+75.8pp
pkg/auth/providers/aws	0%	67.8%	+67.8pp
pkg/auth/identities/aws	2.3%	62.5%	+60.2pp

Overall: ~6% → ~80% ✅

Key Additions

1. Mock Provider Unit Tests (100% coverage)

• pkg/auth/providers/mock/provider_test.go - 15 comprehensive tests
• pkg/auth/providers/mock/identity_test.go - 13 comprehensive tests
• Tests cover: authentication, expiration, concurrency, interface compliance

2. Credential Caching Regression Tests

• cmd/auth_caching_test.go - 4 test functions with multiple subtests
• Verifies credentials are cached after login and reused
• Ensures fast execution (< 2s) vs browser auth (5-30s)
• Tests multi-identity scenarios

3. Integration Test Scenarios

• tests/test-cases/auth-mock.yaml - 20+ test scenarios
• Auth login, whoami, env, exec, list, logout commands
• Multiple output formats (json, bash, dotenv)
• Error handling and edge cases

User Issue: Browser Auth on Every Command

Status: LIKELY FIXED ✅

The issue where browser authentication was triggered on every command appears to have been resolved by recent PRs (#1655, #1653, #1640). This PR adds comprehensive regression tests to:

1. Verify credentials are cached after authentication
2. Ensure subsequent commands use cached credentials
3. Confirm fast execution without browser prompts
4. Prevent regression of this issue

Testing

# Run mock provider tests
$ go test ./pkg/auth/providers/mock/... -v
=== RUN   TestNewProvider
=== RUN   TestProvider_Authenticate
=== RUN   TestProvider_Concurrency
... 28 tests PASS
coverage: 100.0% of statements

# Run auth package tests
$ go test -cover ./pkg/auth/...
pkg/auth: 84.6% coverage ✅
pkg/auth/providers/mock: 100% coverage ✅
pkg/auth/utils: 100% coverage ✅
... all passing

Benefits

• No cloud credentials needed for auth testing
• Fast test execution (milliseconds vs seconds)
• Deterministic results (fixed expiration dates)
• CI/CD ready (no secrets required)
• Regression protection for caching issue
• 80% coverage meets industry standards

references

• User complaint: Bogdan reported browser auth on every command
• Related PRs: Improve auth login with identity selection #1655, Add spinner and TTY dialog for AWS SSO auth #1653, feat: Add atmos auth shell command #1640 (auth improvements)
• Mock provider enables testing without cloud credentials

[mergify]

Warning

This PR exceeds the recommended limit of 1,000 lines.

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Please verify that this PR does not address multiple issues.
Consider refactoring it into smaller, more focused PRs to facilitate a smoother review process.

[github-actions]

Dependency Review

✅ No vulnerabilities or license issues or OpenSSF Scorecard issues found.

Scanned Files

None

[codecov]

Codecov Report

❌ Patch coverage is 80.48780% with 8 lines in your changes missing coverage. Please review.
✅ Project coverage is 67.55%. Comparing base (3ace69f) to head (ac75981).
⚠️ Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
pkg/auth/credentials/keyring_file.go	78.37%	4 Missing and 4 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1702      +/-   ##
==========================================
+ Coverage   66.87%   67.55%   +0.67%     
==========================================
  Files         368      368              
  Lines       42960    42981      +21     
==========================================
+ Hits        28731    29037     +306     
+ Misses      12135    11815     -320     
- Partials     2094     2129      +35     

Flag	Coverage Δ
unittests	67.55% <80.48%> (+0.67%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
cmd/auth_login.go	83.15% <100.00%> (+57.62%)	⬆️
pkg/auth/credentials/keyring_file.go	73.66% <78.37%> (-0.36%)	⬇️

... and 10 files with indirect coverage changes

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[github-actions]

These changes were released in v1.196.0-rc.1.