PowerShell Fortran Runner for VS Code

A powerful set of scripts to compile and run Fortran code on Windows with a single command, directly from the VS Code terminal.

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This project automates the entire Fortran compile-and-run cycle into a single, easy-to-remember command (frun). It automatically detects the active file in your VS Code editor, compiles it with gfortran, and immediately runs the resulting executable, regardless of your terminal's current location.

Features

• ✅ One-Command Execution: Compile and run your active Fortran file with the single command frun.
• 🔎 Auto-Detection: Automatically finds the .f90, .f95, etc. file you are currently editing in VS Code.
• 📂 Works From Anywhere: The script automatically changes to your file's directory to compile and run, so you don't have to.
• 🚀 Dedicated Installer: A one-time installer script (Install-FortranAlias.ps1) creates a permanent, location-aware alias. No manual profile editing required!
• ⚠️ Error Checking: Checks if compilation was successful before attempting to run the program.
• 💬 User-Friendly Feedback: Provides clear status messages and error reports directly in the terminal.

Prerequisites

Before you begin, you need to have the following software installed and configured on your Windows machine.

1. Visual Studio Code

The script is designed to integrate with VS Code. You can download it from the official website:

• ➡️ Download Visual Studio Code

2. A Fortran Compiler (gfortran)

You need the gfortran compiler to be accessible from PowerShell. For most users, Option 1 is the fastest and easiest way to get started.

Option 1: Quick Setup via Equation.com (Recommended)

This method uses a simple installer that bundles the gfortran compiler and automatically adds it to your system's PATH. No manual configuration is needed.

1. Download: Go to the Equation.com Fortran page:
   • ➡️ Download TDM-GCC MinGW Compiler
2. Install: Run the downloaded .exe installer and follow the on-screen instructions. The default settings are fine.
3. Verify: To confirm the installation was successful, open a new PowerShell terminal and type the following command:

   gfortran --version

   You should see the compiler's version information. If you get an error, try restarting your computer to ensure the environment variables are updated.

Option 2: Full Environment via MSYS2 (Advanced)

This method is for users who may want a more complete development environment with other tools. It requires manually adding the compiler to the Windows PATH.

1. Download: Go to the MSYS2 website and follow their installation instructions.
2. Install gfortran: Once MSYS2 is installed, open the MSYS2 terminal and run:

   pacman -S --needed base-devel mingw-w64-ucrt-x86_64-toolchain

3. Add to Windows PATH: Manually add the compiler's bin folder (e.g., C:\msys64\ucrt64\bin) to your Windows PATH environment variable.
4. Verify: Open a new PowerShell terminal and check the version with gfortran --version.

3. VS Code Fortran Extension (Recommended)

While not required for the script to work, a good Fortran extension provides syntax highlighting and other essential features.

• ➡️ Modern Fortran - A popular and well-maintained choice.

Installation & Setup

This setup uses two scripts: one to install the alias (Install-FortranAlias.ps1) and one to perform the compilation (Invoke-FortranRun.ps1).

Step 1: Download the Scripts

Download both Install-FortranAlias.ps1 and Invoke-FortranRun.ps1 and save them in the same folder. This folder should be a permanent location on your computer. A good place is C:\Users\YourUser\Scripts.

Step 2: Unblock the Scripts

Windows security may block scripts downloaded from the internet. To unblock them:

1. Right-click on each script file and select "Properties".
2. On the "General" tab, check the "Unblock" box at the bottom and click "OK".

Alternatively, you can run this command in PowerShell for each file:

Unblock-File -Path "C:\Path\To\Your\Scripts\Install-FortranAlias.ps1"
Unblock-File -Path "C:\Path\To\Your\Scripts\Invoke-FortranRun.ps1"

Step 3: Run the Installer Script

This is the magic step. The installer script will set up its own permanent alias (frun) for you.

1. Open PowerShell.
2. Navigate to the directory where you saved the scripts.
3. Run the installer script:

   .\Install-FortranAlias.ps1

You will see a confirmation message that the alias has been added to your PowerShell profile. This script automatically detects the correct path, so you never have to edit it manually.

Step 4: Reload Your PowerShell Profile

For the new frun alias to be available, you must reload your PowerShell profile.

• Easiest way: Close and reopen your VS Code terminal or PowerShell window.
• Alternatively: Run . $PROFILE in your current terminal session.

How to Use

Your development workflow will now be incredibly simple.

1. Open your Fortran project folder in VS Code.
2. Open any Fortran file (e.g., my_program.f95) and make sure it is your active, focused tab.
3. When you're ready to test, open the integrated terminal in VS Code (Ctrl + `).
4. Type the magic command and press Enter:

   frun

The script will find your active file, switch to its directory, compile it into an .exe, and run it for you, all in one go.

Troubleshooting

Problem: frun : The term 'frun' is not recognized...

• Cause: You haven't restarted your PowerShell terminal after running the installer script.
• Solution: Close and reopen your terminal. If it persists, run the Install-FortranAlias.ps1 script again and check for any error messages.

Problem: gfortran : The term 'gfortran' is not recognized...

• Cause: The compiler is not in your Windows PATH, or you haven't restarted your terminal since it was added.
• Solution: If you used the Equation.com installer (Option 1), try restarting your computer. If you used MSYS2 (Option 2), double-check that you added the correct directory to your Windows PATH. In either case, ensure gfortran --version works in a new terminal.

Problem: ...cannot be loaded because running scripts is disabled on this system.

• Cause: Your PowerShell Execution Policy is too restrictive.
• Solution: Open PowerShell as an Administrator and run the following command:

  Set-ExecutionPolicy -ExecutionPolicy RemoteSigned -Scope CurrentUser

  Answer Y (Yes) when prompted.

Problem: ERROR: No active Fortran file... found in VS Code.

• Cause: The script could not determine which file you are working on.
• Solution: Make sure the Fortran file you want to compile is the currently active and focused tab in your VS Code window. The script reads the window title to find the file name.

Contributing

Contributions are welcome! If you have ideas for improvements or find a bug, please open an issue or submit a pull request.

License

This project is licensed under the MIT License.