Update installation instructions and CI workflow for macOS support

Author: AndrewSazonov

.github/workflows/pypi-test.yml

@@ -48,6 +48,9 @@ jobs:
       - name: Init pixi project
         run: pixi init easydiffraction
 
+      - name: Set the minimum system requirements
+        run: pixi project system-requirements add macos 14.0
+
       - name: Add Python 3.14 from Conda
         working-directory: easydiffraction
         run: pixi add "python=3.14"
@@ -58,22 +61,25 @@ jobs:
           pixi add gsl
           pixi add --platform osx-arm64 libcxx
 
-      - name: Add easydiffraction from PyPI
-        working-directory: easydiffraction
-        run: pixi add --pypi "easydiffraction"
-
-      - name: Add dev dependencies from PyPI
+      - name: Add pycrysfml calculator from custom PyPI index
         working-directory: easydiffraction
-        run: pixi add --pypi pytest pytest-xdist
+        run: |
+          echo '' >> pixi.toml
+          echo '[pypi-dependencies]' >> pixi.toml
+          echo 'pycrysfml = { version = ">=0.2.1", index = "https://easyscience.github.io/pypi/" }' >> pixi.toml
 
-      - name: Add Pixi task as a shortcut
+      - name: Add easydiffraction (with dev dependencies) from PyPI
         working-directory: easydiffraction
-        run: pixi task add easydiffraction "python -m easydiffraction"
+        run: pixi add --pypi "easydiffraction[dev]"
 
       - name: Run unit tests to verify the installation
         working-directory: easydiffraction
         run: pixi run python -m pytest ../tests/unit/ --color=yes -v
 
+      - name: Run functional tests to verify the installation
+        working-directory: easydiffraction
+        run: pixi run python -m pytest ../tests/functional/ --color=yes -v
+
       - name: Run integration tests to verify the installation
         working-directory: easydiffraction
         run: pixi run python -m pytest ../tests/integration/ --color=yes -n auto

docs/docs/installation-and-setup/index.md

@@ -62,10 +62,22 @@ This section describes the simplest way to set up EasyDiffraction using
   pixi init easydiffraction
   cd easydiffraction
   ```
+- If you are on macOS, set the minimum system requirements:
+  ```txt
+  pixi project system-requirements add macos 14.0
+  ```
 - Set the Python version for the Pixi environment (e.g., 3.14):
   ```txt
   pixi add python=3.14
   ```
+- Add GNU Scientific Library (required for PDF calculations):
+  ```txt
+  pixi add gsl
+  ```
+- If you are on macOS, add libc++ (required for PDF calculations):
+  ```txt
+  pixi add --platform osx-arm64 libcxx
+  ```
 - Add EasyDiffraction to the Pixi environment from PyPI:
   ```txt
   pixi add --pypi easydiffraction