Code Coverage Improvement Plan — cli/azd (Phase 4+)

[jongio]

Code Coverage Improvement Plan — cli/azd

Background

Over the past month, we've executed a multi-phase effort to improve test coverage in the azure-dev CLI. This issue tracks the overall progress, documents what's been accomplished, and outlines the remaining work.

Coverage Journey (March–April 2026)

Phase	PR	Key Changes	Coverage Impact
Foundation	#7188	Enforce minimum coverage threshold in CI pipeline	CI gate established
Wave 1	#7297	Unit test coverage across core packages	Initial lift
Wave 2	#7369	Coverage wave 2 + test timing infrastructure	~48% → 52%
Phase 1-2	#7424	Coverage tooling, mage targets, developer workflow, Phase 1-2 tests	52% → 55%
Phase 3	#7496	cmd, project, azapi, pipeline, grpcserver coverage	55% → 58% (current CI gate)

Tooling introduced:

• mage coverage:unit / :full / :hybrid / :ci / :html / :check — developer coverage workflow
• Get-LocalCoverageReport.ps1 / Get-CICoverageReport.ps1 — coverage report scripts
• Test-TestTiming.ps1 — test timing analysis to catch slow tests

Current State (April 2026)

Overall: 876 source files, 627 test files (0.72 ratio), CI threshold at 58%.

Latest Coverage Improvements (In Progress — Not Yet in PR)

Package	Before	After	Delta
pkg/ioc	36.2%	95.0%	+58.8
internal/cmd/add	16.1%	26.7%	+10.6
pkg/extensions	75.1%	79.3%	+4.2
pkg/exec	69.5%	72.9%	+3.4
pkg/auth	80.0%	80.2%	+0.2

9 new test files covering: sanitizer_test.go, runresult_test.go, remote_credential_test.go, credential_providers_test.go, command_resolver_test.go, extension_test.go, runner_test.go, container_coverage_test.go (ioc), add_coverage_test.go

Remaining Gaps — Prioritized

🔴 Tier 1: Critical (< 20% coverage)

Package	Coverage	Priority	Notes
pkg/devcentersdk	4.3%	HIGH	SDK — needs httptest/recording tests
pkg/azdo	8.4%	HIGH	Azure DevOps pipeline integration
pkg/azureutil	10.0%	MEDIUM	Location/principal utils (small surface)
pkg/ux/internal	10.6%	HIGH	Core UX input framework
pkg/azsdk/storage	14.5%	MEDIUM	Azure Storage SDK wrapper
pkg/apphost	18.7%	HIGH	.NET Aspire app host support

🟡 Tier 2: Below Threshold (20-50%)

Package	Coverage	Priority	Notes
pkg/azdext	24.9%	MEDIUM	Extension SDK
pkg/azsdk	25.4%	MEDIUM	Azure SDK core wrappers
pkg/tools/dotnet	26.6%	MEDIUM	.NET tool integration
internal/cmd/add	26.7%	MEDIUM	azd add command (improved from 16.1%)
pkg/prompt	31.3%	MEDIUM	Prompt framework
pkg/github	35.7%	MEDIUM	GitHub integration
pkg/containerregistry	37.1%	MEDIUM	ACR wrapper
pkg/environment/azdcontext	37.2%	HIGH	Core environment context
pkg/ai	37.8%	MEDIUM	AI integration
pkg/output	41.4%	LOW	Output formatting
pkg/keyvault	41.5%	MEDIUM	Key Vault integration
pkg/tools/bicep	44.1%	MEDIUM	Bicep tool
internal/agent/copilot	45.3%	LOW	Copilot agent
internal/vsrpc	46.4%	LOW	VS RPC service
pkg/infra/provisioning/bicep	49.7%	MEDIUM	Bicep provisioning

🟢 Tier 3: Modernization and Quality

• Migrate context.Background() → t.Context() — 241 test files still use the old pattern (Go 1.26+ has t.Context())
• Reduce time.Sleep in tests — 12 files use time.Sleep, replace with polling/event-based waiting
• Remove stale t.Skip — 26 files with 58 skip calls that may hide coverage gaps
• Raise CI coverage gate — Current 58%, next target 65%

Proposed Next Phases

Phase 4: Close Critical Gaps (target: 62% overall)

• Add httptest-based tests for pkg/devcentersdk (4.3% → 40%+)
• Add tests for pkg/azdo (8.4% → 40%+)
• Improve pkg/ux/internal (10.6% → 50%+)
• Add tests for pkg/apphost (18.7% → 40%+)
• Improve pkg/environment/azdcontext (37.2% → 60%+)

Phase 5: Raise the Floor (target: 65% overall)

• Get all Tier 2 packages above 50%
• Focus on: azdext, azsdk, prompt, github, containerregistry, ai
• Raise CI coverage gate from 58% → 65%

Phase 6: Modernization

• Bulk migrate context.Background() → t.Context() across 241 test files
• Replace time.Sleep with proper async waiting patterns
• Audit and fix or remove t.Skip calls

Test Quality Strengths (preserve these)

• Table-driven tests: 287 files, 654 occurrences
• Subtests: 415 files, 2,499 t.Run calls
• Error path testing: 306 files with require.Error
• Parallel tests: 153 files, 2,318 t.Parallel() calls
• Modern Go 1.26: 98 files already using t.Context()
• Rich mock infrastructure: test/mocks/, test/recording/

How to Measure Progress

# Local unit coverage (quick)
mage coverage:unit

# Full local coverage (unit + integration)
mage coverage:full

# Hybrid (local unit + CI integration)
mage coverage:hybrid

# Check threshold
COVERAGE_MIN=65 mage coverage:check

# HTML report
mage coverage:html

[jongio]

Detailed implementation plan for the coverage % goal in epic #7660 (Test coverage and quality gates).

This issue tracks the package-level Phase 4+ coverage roadmap. Other scope items in the epic (playback PR gates, coverage diff tooling, validation coverage, PR governance) are tracked as separate sub-issues.