Add merge conflict marker detection to linux-ci workflow and refactor existing actions to use reusable get-changed-files action (#26350)

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com> Co-authored-by: TravisEz13 <10873629+TravisEz13@users.noreply.github.com> Co-authored-by: Travis Plunk <travis.plunk@microsoft.com> Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com> Co-authored-by: Travis Plunk (HE/HIM) <tplunk@ntdev.microsoft.com>
2026-06-08 12:12:50 +00:00 · 2025-10-31 18:00:55 +00:00
parent c12322323d
commit 0c40a84abb
10 changed files with 1001 additions and 62 deletions
@@ -0,0 +1,84 @@
+# Merge Conflict Checker
+
+This composite GitHub Action checks for Git merge conflict markers in files changed in pull requests.
+
+## Purpose
+
+Automatically detects leftover merge conflict markers (`<<<<<<<`, `=======`, `>>>>>>>`) in pull request files to prevent them from being merged into the codebase.
+
+## Usage
+
+### In a Workflow
+
+```yaml
+- name: Check for merge conflict markers
+  uses: "./.github/actions/infrastructure/merge-conflict-checker"
+```
+
+### Complete Example
+
+```yaml
+jobs:
+  merge_conflict_check:
+    name: Check for Merge Conflict Markers
+    runs-on: ubuntu-latest
+    if: github.event_name == 'pull_request'
+    permissions:
+      pull-requests: read
+      contents: read
+    steps:
+      - name: checkout
+        uses: actions/checkout@v5
+
+      - name: Check for merge conflict markers
+        uses: "./.github/actions/infrastructure/merge-conflict-checker"
+```
+
+## How It Works
+
+1. **File Detection**: Uses GitHub's API to get the list of files changed in the pull request
+2. **Marker Scanning**: Reads each changed file and searches for the following markers:
+   - `<<<<<<<` (conflict start marker)
+   - `=======` (conflict separator)
+   - `>>>>>>>` (conflict end marker)
+3. **Result Reporting**: 
+   - If markers are found, the action fails and lists all affected files
+   - If no markers are found, the action succeeds
+
+## Outputs
+
+- `files-checked`: Number of files that were checked
+- `conflicts-found`: Number of files containing merge conflict markers
+
+## Behavior
+
+- **Event Support**: Only works with `pull_request` events
+- **File Handling**:
+  - Checks only files that were added, modified, or renamed
+  - Skips deleted files
+  - Skips binary/unreadable files
+  - Skips directories
+
+## Example Output
+
+When conflict markers are detected:
+
+```
+❌ Merge conflict markers detected in the following files:
+  - src/example.cs
+    Markers found: <<<<<<<, =======, >>>>>>>
+  - README.md
+    Markers found: <<<<<<<, =======, >>>>>>>
+
+Please resolve these conflicts before merging.
+```
+
+When no markers are found:
+
+```
+✅ No merge conflict markers found
+```
+
+## Integration
+
+This action is integrated into the `linux-ci.yml` workflow and runs automatically on all pull requests to ensure code quality before merging.
@@ -0,0 +1,36 @@
+name: 'Check for Merge Conflict Markers'
+description: 'Checks for Git merge conflict markers in changed files for pull requests'
+author: 'PowerShell Team'
+
+outputs:
+  files-checked:
+    description: 'Number of files checked for merge conflict markers'
+    value: ${{ steps.check.outputs.files-checked }}
+  conflicts-found:
+    description: 'Number of files with merge conflict markers'
+    value: ${{ steps.check.outputs.conflicts-found }}
+
+runs:
+  using: 'composite'
+  steps:
+    - name: Get changed files
+      id: changed-files
+      uses: "./.github/actions/infrastructure/get-changed-files"
+
+    - name: Check for merge conflict markers
+      id: check
+      shell: pwsh
+      env:
+        CHANGED_FILES_JSON: ${{ steps.changed-files.outputs.files }}
+      run: |
+        # Get changed files from environment variable (secure against injection)
+        $changedFilesJson = $env:CHANGED_FILES_JSON
+        $changedFiles = $changedFilesJson | ConvertFrom-Json
+
+        # Import ci.psm1 and run the check
+        Import-Module "$env:GITHUB_WORKSPACE/tools/ci.psm1" -Force
+        Test-MergeConflictMarker -File $changedFiles -WorkspacePath $env:GITHUB_WORKSPACE
+
+branding:
+  icon: 'alert-triangle'
+  color: 'red'
@@ -31,6 +31,12 @@ runs:
      Invoke-CIFinish
    shell: pwsh

+  - name: Install Pester
+    run: |-
+      Import-Module ./tools/ci.psm1
+      Install-CIPester
+    shell: pwsh
+
  - name: Validate Package Names
    run: |-
      # Run Pester tests to validate package names
@@ -0,0 +1,159 @@
+---
+applyTo:
+  - "**/*.ps1"
+  - "**/*.psm1"
+---
+
+# PowerShell Automatic Variables - Naming Guidelines
+
+## Purpose
+
+This instruction provides guidelines for avoiding conflicts with PowerShell's automatic variables when writing PowerShell scripts and modules.
+
+## What Are Automatic Variables?
+
+PowerShell has built-in automatic variables that are created and maintained by PowerShell itself. Assigning values to these variables can cause unexpected behavior and side effects.
+
+## Common Automatic Variables to Avoid
+
+### Critical Variables (Never Use)
+
+- **`$matches`** - Contains the results of regular expression matches. Overwriting this can break regex operations.
+- **`$_`** - Represents the current object in the pipeline. Only use within pipeline blocks.
+- **`$PSItem`** - Alias for `$_`. Same rules apply.
+- **`$args`** - Contains an array of undeclared parameters. Don't use as a regular variable.
+- **`$input`** - Contains an enumerator of all input passed to a function. Don't reassign.
+- **`$LastExitCode`** - Exit code of the last native command. Don't overwrite unless intentional.
+- **`$?`** - Success status of the last command. Don't use as a variable name.
+- **`$$`** - Last token in the last line received by the session. Don't use.
+- **`$^`** - First token in the last line received by the session. Don't use.
+
+### Context Variables (Use with Caution)
+
+- **`$Error`** - Array of error objects. Don't replace, but can modify (e.g., `$Error.Clear()`).
+- **`$PSBoundParameters`** - Parameters passed to the current function. Read-only.
+- **`$MyInvocation`** - Information about the current command. Read-only.
+- **`$PSCmdlet`** - Cmdlet object for advanced functions. Read-only.
+
+### Other Common Automatic Variables
+
+- `$true`, `$false`, `$null` - Boolean and null constants
+- `$HOME`, `$PSHome`, `$PWD` - Path-related variables
+- `$PID` - Process ID of the current PowerShell session
+- `$Host` - Host application object
+- `$PSVersionTable` - PowerShell version information
+
+For a complete list, see: https://learn.microsoft.com/powershell/module/microsoft.powershell.core/about/about_automatic_variables
+
+## Best Practices
+
+### ❌ Bad - Using Automatic Variable Names
+
+```powershell
+# Bad: $matches is an automatic variable used for regex capture groups
+$matches = Select-String -Path $file -Pattern $pattern
+
+# Bad: $args is an automatic variable for undeclared parameters
+$args = Get-ChildItem
+
+# Bad: $input is an automatic variable for pipeline input
+$input = Read-Host "Enter value"
+```
+
+### ✅ Good - Using Descriptive Alternative Names
+
+```powershell
+# Good: Use descriptive names that avoid conflicts
+$matchedLines = Select-String -Path $file -Pattern $pattern
+
+# Good: Use specific names for arguments
+$arguments = Get-ChildItem
+
+# Good: Use specific names for user input
+$userInput = Read-Host "Enter value"
+```
+
+## Naming Alternatives
+
+When you encounter a situation where you might use an automatic variable name, use these alternatives:
+
+| Avoid | Use Instead |
+|-------|-------------|
+| `$matches` | `$matchedLines`, `$matchResults`, `$regexMatches` |
+| `$args` | `$arguments`, `$parameters`, `$commandArgs` |
+| `$input` | `$userInput`, `$inputValue`, `$inputData` |
+| `$_` (outside pipeline) | Use a named parameter or explicit variable |
+| `$Error` (reassignment) | Don't reassign; use `$Error.Clear()` if needed |
+
+## How to Check
+
+### PSScriptAnalyzer Rule
+
+PSScriptAnalyzer has a built-in rule that detects assignments to automatic variables:
+
+```powershell
+# This will trigger PSAvoidAssignmentToAutomaticVariable
+$matches = Get-Something
+```
+
+**Rule ID**: PSAvoidAssignmentToAutomaticVariable
+
+### Manual Review
+
+When writing PowerShell code, always:
+1. Avoid variable names that match PowerShell keywords or automatic variables
+2. Use descriptive, specific names that clearly indicate the variable's purpose
+3. Run PSScriptAnalyzer on your code before committing
+4. Review code for variable naming during PR reviews
+
+## Examples from the Codebase
+
+### Example 1: Regex Matching
+
+```powershell
+# ❌ Bad - Overwrites automatic $matches variable
+$matches = [regex]::Matches($content, $pattern)
+
+# ✅ Good - Uses descriptive name
+$regexMatches = [regex]::Matches($content, $pattern)
+```
+
+### Example 2: Select-String Results
+
+```powershell
+# ❌ Bad - Conflicts with automatic $matches
+$matches = Select-String -Path $file -Pattern $pattern
+
+# ✅ Good - Clear and specific
+$matchedLines = Select-String -Path $file -Pattern $pattern
+```
+
+### Example 3: Collecting Arguments
+
+```powershell
+# ❌ Bad - Conflicts with automatic $args
+function Process-Items {
+    $args = $MyItems
+    # ... process items
+}
+
+# ✅ Good - Descriptive parameter name
+function Process-Items {
+    [CmdletBinding()]
+    param(
+        [Parameter(ValueFromRemainingArguments)]
+        [string[]]$Items
+    )
+    # ... process items
+}
+```
+
+## References
+
+- [PowerShell Automatic Variables Documentation](https://learn.microsoft.com/powershell/module/microsoft.powershell.core/about/about_automatic_variables)
+- [PSScriptAnalyzer Rules](https://github.com/PowerShell/PSScriptAnalyzer/blob/master/docs/Rules/README.md)
+- [PowerShell Best Practices](https://learn.microsoft.com/powershell/scripting/developer/cmdlet/strongly-encouraged-development-guidelines)
+
+## Summary
+
+**Key Takeaway**: Always use descriptive, specific variable names that clearly indicate their purpose and avoid conflicts with PowerShell's automatic variables. When in doubt, choose a longer, more descriptive name over a short one that might conflict.
@@ -0,0 +1,201 @@
+---
+applyTo:
+  - "tools/ci.psm1"
+  - "build.psm1"
+  - "tools/packaging/**/*.psm1"
+  - ".github/**/*.yml"
+  - ".github/**/*.yaml"
+---
+
+# Guidelines for PowerShell Code Organization
+
+## When to Move Code from YAML to PowerShell Modules
+
+PowerShell code in GitHub Actions YAML files should be kept minimal. Move code to a module when:
+
+### Size Threshold
+- **More than ~30 lines** of PowerShell in a YAML file step
+- **Any use of .NET types** like `[regex]`, `[System.IO.Path]`, etc.
+- **Complex logic** requiring multiple nested loops or conditionals
+- **Reusable functionality** that might be needed elsewhere
+
+### Indicators to Move Code
+1. Using .NET type accelerators (`[regex]`, `[PSCustomObject]`, etc.)
+2. Complex string manipulation or parsing
+3. File system operations beyond basic reads/writes
+4. Logic that would benefit from unit testing
+5. Code that's difficult to read/maintain in YAML format
+
+## Which Module to Use
+
+### ci.psm1 (`tools/ci.psm1`)
+**Purpose**: CI/CD-specific operations and workflows
+
+**Use for**:
+- Build orchestration (invoking builds, tests, packaging)
+- CI environment setup and configuration
+- Test execution and result processing
+- Artifact handling and publishing
+- CI-specific validations and checks
+- Environment variable management for CI
+
+**Examples**:
+- `Invoke-CIBuild` - Orchestrates build process
+- `Invoke-CITest` - Runs Pester tests
+- `Test-MergeConflictMarker` - Validates files for conflicts
+- `Set-BuildVariable` - Manages CI variables
+
+**When NOT to use**:
+- Core build operations (use build.psm1)
+- Package creation logic (use packaging.psm1)
+- Platform-specific build steps
+
+### build.psm1 (`build.psm1`)
+**Purpose**: Core build operations and utilities
+
+**Use for**:
+- Compiling source code
+- Resource generation
+- Build configuration management
+- Core build utilities (New-PSOptions, Get-PSOutput, etc.)
+- Bootstrap operations
+- Cross-platform build helpers
+
+**Examples**:
+- `Start-PSBuild` - Main build function
+- `Start-PSBootstrap` - Bootstrap dependencies
+- `New-PSOptions` - Create build configuration
+- `Start-ResGen` - Generate resources
+
+**When NOT to use**:
+- CI workflow orchestration (use ci.psm1)
+- Package creation (use packaging.psm1)
+- Test execution
+
+### packaging.psm1 (`tools/packaging/packaging.psm1`)
+**Purpose**: Package creation and distribution
+
+**Use for**:
+- Creating distribution packages (MSI, RPM, DEB, etc.)
+- Package-specific metadata generation
+- Package signing operations
+- Platform-specific packaging logic
+
+**Examples**:
+- `Start-PSPackage` - Create packages
+- `New-MSIPackage` - Create Windows MSI
+- `New-DotnetSdkContainerFxdPackage` - Create container packages
+
+**When NOT to use**:
+- Building binaries (use build.psm1)
+- Running tests (use ci.psm1)
+- General utilities
+
+## Best Practices
+
+### Keep YAML Minimal
+```yaml
+# ❌ Bad - too much logic in YAML
+- name: Check files
+  shell: pwsh
+  run: |
+    $files = Get-ChildItem -Recurse
+    foreach ($file in $files) {
+      $content = Get-Content $file -Raw
+      if ($content -match $pattern) {
+        # ... complex processing ...
+      }
+    }
+
+# ✅ Good - call function from module
+- name: Check files
+  shell: pwsh
+  run: |
+    Import-Module ./tools/ci.psm1
+    Test-SomeCondition -Path ${{ github.workspace }}
+```
+
+### Document Functions
+Always include comment-based help for functions:
+```powershell
+function Test-MyFunction
+{
+    <#
+    .SYNOPSIS
+        Brief description
+    .DESCRIPTION
+        Detailed description
+    .PARAMETER ParameterName
+        Parameter description
+    .EXAMPLE
+        Test-MyFunction -ParameterName Value
+    #>
+    [CmdletBinding()]
+    param(
+        [Parameter(Mandatory)]
+        [string] $ParameterName
+    )
+    # Implementation
+}
+```
+
+### Error Handling
+Use proper error handling in modules:
+```powershell
+try {
+    # Operation
+}
+catch {
+    Write-Error "Detailed error message: $_"
+    throw
+}
+```
+
+### Verbose Output
+Use `Write-Verbose` for debugging information:
+```powershell
+Write-Verbose "Processing file: $filePath"
+```
+
+## Module Dependencies
+
+- **ci.psm1** imports both `build.psm1` and `packaging.psm1`
+- **build.psm1** is standalone (minimal dependencies)
+- **packaging.psm1** imports `build.psm1`
+
+When adding new functions, consider these import relationships to avoid circular dependencies.
+
+## Testing Modules
+
+Functions in modules should be testable:
+```powershell
+# Test locally
+Import-Module ./tools/ci.psm1 -Force
+Test-MyFunction -Parameter Value
+
+# Can be unit tested with Pester
+Describe "Test-MyFunction" {
+    It "Should return expected result" {
+        # Test implementation
+    }
+}
+```
+
+## Migration Checklist
+
+When moving code from YAML to a module:
+
+1. ✅ Determine which module is appropriate (ci, build, or packaging)
+2. ✅ Create function with proper parameter validation
+3. ✅ Add comment-based help documentation
+4. ✅ Use `[CmdletBinding()]` for advanced function features
+5. ✅ Include error handling
+6. ✅ Add verbose output for debugging
+7. ✅ Test the function independently
+8. ✅ Update YAML to call the new function
+9. ✅ Verify the workflow still works end-to-end
+
+## References
+
+- PowerShell Advanced Functions: https://learn.microsoft.com/powershell/module/microsoft.powershell.core/about/about_functions_advanced
+- Comment-Based Help: https://learn.microsoft.com/powershell/scripting/developer/help/writing-help-for-windows-powershell-scripts-and-functions
@@ -67,6 +67,20 @@ jobs:
        with:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

+  merge_conflict_check:
+    name: Check for Merge Conflict Markers
+    runs-on: ubuntu-latest
+    if: github.event_name == 'pull_request' && (startsWith(github.repository_owner, 'azure') || github.repository_owner == 'PowerShell')
+    permissions:
+      pull-requests: read
+      contents: read
+    steps:
+      - name: checkout
+        uses: actions/checkout@v5
+
+      - name: Check for merge conflict markers
+        uses: "./.github/actions/infrastructure/merge-conflict-checker"
+
  ci_build:
    name: Build PowerShell
    runs-on: ubuntu-latest
@@ -158,6 +172,48 @@ jobs:
      runner_os: ubuntu-latest
      test_results_artifact_name: testResults-xunit

+  infrastructure_tests:
+    name: Infrastructure Tests
+    runs-on: ubuntu-latest
+    steps:
+      - name: checkout
+        uses: actions/checkout@v5
+        with:
+          fetch-depth: 1
+
+      - name: Install Pester
+        shell: pwsh
+        run: |
+          Import-Module ./tools/ci.psm1
+          Install-CIPester
+
+      - name: Run Infrastructure Tests
+        shell: pwsh
+        run: |
+          $testResultsFolder = Join-Path $PWD "testResults"
+          New-Item -ItemType Directory -Path $testResultsFolder -Force | Out-Null
+
+          $config = New-PesterConfiguration
+          $config.Run.Path = './test/infrastructure/'
+          $config.Run.PassThru = $true
+          $config.TestResult.Enabled = $true
+          $config.TestResult.OutputFormat = 'NUnitXml'
+          $config.TestResult.OutputPath = "$testResultsFolder/InfrastructureTests.xml"
+          $config.Output.Verbosity = 'Detailed'
+
+          $result = Invoke-Pester -Configuration $config
+
+          if ($result.FailedCount -gt 0 -or $result.Result -eq 'Failed') {
+            throw "Infrastructure tests failed"
+          }
+
+      - name: Publish Test Results
+        uses: "./.github/actions/test/process-pester-results"
+        if: always()
+        with:
+          name: "InfrastructureTests"
+          testResultsFolder: "${{ github.workspace }}/testResults"
+
  ## Temporarily disable the CodeQL analysis on Linux as it doesn't work for .NET SDK 10-rc.2.
  # analyze:
  #   name: CodeQL Analysis
@@ -180,6 +236,8 @@ jobs:
      - linux_test_unelevated_ci
      - linux_test_unelevated_others
      - linux_packaging
+      - merge_conflict_check
+      - infrastructure_tests
      # - analyze
    if: always()
    uses: PowerShell/compliance/.github/workflows/ready-to-merge.yml@v1.0.0
@@ -187,6 +187,14 @@ jobs:
        $macOSRuntime = if ([System.Runtime.InteropServices.RuntimeInformation]::OSArchitecture -eq 'Arm64') { 'osx-arm64' } else { 'osx-x64' }
        Start-PSPackage -Type osxpkg -ReleaseTag $releaseTag -MacOSRuntime $macOSRuntime -SkipReleaseChecks
      shell: pwsh
+
+    - name: Install Pester
+      if: success()
+      run: |-
+        Import-Module ./tools/ci.psm1
+        Install-CIPester
+      shell: pwsh
+
    - name: Test package contents
      if: success()
      run: |-