windows-git-bash-compatibility

What this skill does

# Windows & Git Bash Compatibility for Azure Data Factory

## Overview

Azure Data Factory development frequently occurs on Windows machines using Git Bash (MINGW64) as the primary shell. This introduces path conversion challenges that can break CI/CD pipelines, npm commands, and deployment scripts.

## Git Bash Path Conversion Behavior

### Automatic Path Conversion

Git Bash (MINGW) automatically converts Unix-style paths to Windows paths:

**Conversions:**
- `/foo` → `C:/Program Files/Git/usr/foo`
- `/foo:/bar` → `C:\msys64\foo;C:\msys64\bar` (path lists)
- `--dir=/foo` → `--dir=C:/msys64/foo` (arguments)

**What Triggers Conversion:**
- Leading forward slash (`/`) in arguments
- Colon-separated path lists
- Arguments after `-` or `,` with path components

**What's Exempt:**
- Arguments containing `=` (variable assignments)
- Drive specifiers (`C:`)
- Arguments with `;` (already Windows format)
- Arguments starting with `//` (Windows switches)

## ADF-Specific Path Issues

### npm Build Commands

**Problem:**
```bash
# This fails in Git Bash due to path conversion
npm run build validate ./adf-resources /subscriptions/abc/resourceGroups/rg/providers/Microsoft.DataFactory/factories/myFactory

# Path gets converted incorrectly
```

**Solution:**
```bash
# Disable path conversion before running
export MSYS_NO_PATHCONV=1
npm run build validate ./adf-resources /subscriptions/abc/resourceGroups/rg/providers/Microsoft.DataFactory/factories/myFactory

# Or wrap the command
MSYS_NO_PATHCONV=1 npm run build export ./adf-resources /subscriptions/.../myFactory "ARMTemplate"
```

### PowerShell Scripts

**Problem:**
```bash
# Calling PowerShell scripts from Git Bash
pwsh ./PrePostDeploymentScript.Ver2.ps1 -armTemplate "./ARMTemplate/ARMTemplateForFactory.json"
# Path conversion may interfere
```

**Solution:**
```bash
# Disable conversion for PowerShell calls
MSYS_NO_PATHCONV=1 pwsh ./PrePostDeploymentScript.Ver2.ps1 -armTemplate "./ARMTemplate/ARMTemplateForFactory.json"
```

### ARM Template Paths

**Problem:**
```bash
# Azure CLI deployment from Git Bash
az deployment group create \
  --resource-group myRG \
  --template-file ARMTemplate/ARMTemplateForFactory.json  # Path may get converted
```

**Solution:**
```bash
# Use relative paths with ./ prefix or absolute Windows paths
export MSYS_NO_PATHCONV=1
az deployment group create \
  --resource-group myRG \
  --template-file ./ARMTemplate/ARMTemplateForFactory.json
```

## Shell Detection Patterns

### Bash Shell Detection

```bash
#!/usr/bin/env bash

# Method 1: Check $MSYSTEM (Git Bash/MSYS2 specific)
if [ -n "$MSYSTEM" ]; then
  echo "Running in Git Bash/MinGW ($MSYSTEM)"
  export MSYS_NO_PATHCONV=1
fi

# Method 2: Check uname -s (more portable)
case "$(uname -s)" in
  MINGW64*|MINGW32*|MSYS*)
    echo "Git Bash detected"
    export MSYS_NO_PATHCONV=1
    ;;
  Linux*)
    if grep -q Microsoft /proc/version 2>/dev/null; then
      echo "WSL detected"
    else
      echo "Native Linux"
    fi
    ;;
  Darwin*)
    echo "macOS"
    ;;
esac

# Method 3: Check $OSTYPE (bash-specific)
case "$OSTYPE" in
  msys*)
    echo "Git Bash/MSYS"
    export MSYS_NO_PATHCONV=1
    ;;
  linux-gnu*)
    echo "Linux"
    ;;
  darwin*)
    echo "macOS"
    ;;
esac
```

### Node.js Shell Detection

```javascript
// detect-shell.js - For use in npm scripts or Node tools
function detectShell() {
  const env = process.env;

  // Git Bash/MinGW (MOST RELIABLE)
  if (env.MSYSTEM) {
    return {
      type: 'mingw',
      subsystem: env.MSYSTEM,  // MINGW64, MINGW32, or MSYS
      needsPathFix: true
    };
  }

  // WSL
  if (env.WSL_DISTRO_NAME) {
    return {
      type: 'wsl',
      distro: env.WSL_DISTRO_NAME,
      needsPathFix: false
    };
  }

  // PowerShell (3+ paths in PSModulePath)
  if (env.PSModulePath?.split(';').length >= 3) {
    return {
      type: 'powershell',
      needsPathFix: false
    };
  }

  // CMD
  if (process.platform === 'win32' && env.PROMPT === '$P$G') {
    return {
      type: 'cmd',
      needsPathFix: false
    };
  }

  // Cygwin
  if (env.TERM === 'cygwin') {
    return {
      type: 'cygwin',
      needsPathFix: true
    };
  }

  // Unix shells
  if (env.SHELL?.includes('bash')) {
    return { type: 'bash', needsPathFix: false };
  }
  if (env.SHELL?.includes('zsh')) {
    return { type: 'zsh', needsPathFix: false };
  }

  return {
    type: 'unknown',
    platform: process.platform,
    needsPathFix: false
  };
}

// Usage
const shell = detectShell();
console.log(`Detected shell: ${shell.type}`);

if (shell.needsPathFix) {
  process.env.MSYS_NO_PATHCONV = '1';
  console.log('Path conversion disabled for Git Bash compatibility');
}

module.exports = { detectShell };
```

### PowerShell Detection

```powershell
# Detect PowerShell edition and version
function Get-ShellInfo {
  $info = @{
    Edition = $PSVersionTable.PSEdition
    Version = $PSVersionTable.PSVersion
    OS = $PSVersionTable.OS
    Platform = $PSVersionTable.Platform
  }

  if ($info.Edition -eq 'Core') {
    Write-Host "PowerShell Core (pwsh) - Cross-platform compatible" -ForegroundColor Green
    $info.CrossPlatform = $true
  } else {
    Write-Host "Windows PowerShell - Windows only" -ForegroundColor Yellow
    $info.CrossPlatform = $false
  }

  return $info
}

$shellInfo = Get-ShellInfo
```

## CI/CD Pipeline Patterns

### Local Development Scripts

**validate-adf.sh** (Git Bash compatible):
```bash
#!/usr/bin/env bash
set -e

# Detect and handle Git Bash
if [ -n "$MSYSTEM" ]; then
  export MSYS_NO_PATHCONV=1
  echo "🔧 Git Bash detected - path conversion disabled"
fi

# Configuration
ADF_ROOT="./adf-resources"
FACTORY_ID="/subscriptions/${AZURE_SUBSCRIPTION_ID}/resourceGroups/${RESOURCE_GROUP}/providers/Microsoft.DataFactory/factories/${FACTORY_NAME}"

# Validate ADF resources
echo "📋 Validating ADF resources..."
npm run build validate "$ADF_ROOT" "$FACTORY_ID"

# Generate ARM templates
echo "📦 Generating ARM templates..."
npm run build export "$ADF_ROOT" "$FACTORY_ID" "ARMTemplate"

echo "✅ Validation complete"
```

**deploy-adf.sh** (Cross-platform):
```bash
#!/usr/bin/env bash
set -e

# Detect shell
detect_shell() {
  if [ -n "$MSYSTEM" ]; then echo "git-bash"
  elif [ -n "$WSL_DISTRO_NAME" ]; then echo "wsl"
  elif [[ "$OSTYPE" == "darwin"* ]]; then echo "macos"
  else echo "linux"
  fi
}

SHELL_TYPE=$(detect_shell)
echo "🖥️  Detected shell: $SHELL_TYPE"

# Handle Git Bash
if [ "$SHELL_TYPE" = "git-bash" ]; then
  export MSYS_NO_PATHCONV=1
fi

# Download PrePostDeploymentScript
curl -sLo PrePostDeploymentScript.Ver2.ps1 \
  https://raw.githubusercontent.com/Azure/Azure-DataFactory/main/SamplesV2/ContinuousIntegrationAndDelivery/PrePostDeploymentScript.Ver2.ps1

# Stop triggers
echo "⏸️  Stopping triggers..."
MSYS_NO_PATHCONV=1 pwsh ./PrePostDeploymentScript.Ver2.ps1 \
  -armTemplate "./ARMTemplate/ARMTemplateForFactory.json" \
  -ResourceGroupName "$RESOURCE_GROUP" \
  -DataFactoryName "$FACTORY_NAME" \
  -predeployment $true \
  -deleteDeployment $false

# Deploy ARM template
echo "🚀 Deploying ARM template..."
az deployment group create \
  --resource-group "$RESOURCE_GROUP" \
  --template-file ./ARMTemplate/ARMTemplateForFactory.json \
  --parameters ./ARMTemplate/ARMTemplateParametersForFactory.json \
  --parameters factoryName="$FACTORY_NAME"

# Start triggers
echo "▶️  Starting triggers..."
MSYS_NO_PATHCONV=1 pwsh ./PrePostDeploymentScript.Ver2.ps1 \
  -armTemplate "./ARMTemplate/ARMTemplateForFactory.json" \
  -ResourceGroupName "$RESOURCE_GROUP" \
  -DataFactoryName "$FACTORY_NAME" \
  -predeployment $false \
  -deleteDeployment $true

echo "✅ Deployment complete"
```

### package.json with Shell Detection

```json
{
  "scripts": {
    "prevalidate": "node scripts/detect-shell.js",
    "validate": "node node_modules/@microsoft/azure-data-factory-utilities/lib/index validate",
    "prebuild": "node scripts/detect-shell.js",
    "build": "node node_modules/@microsoft/azure-data-factory-utilities/lib/inde