Update max Python to 3.14 (#2114)

Also updates `integration-test.yml` to run on the mix and max supported
Python versions

---------

Co-authored-by: Luis Barroso-Luque <lbluque@users.noreply.github.com>

Author: frostedoyster

.github/workflows/integration-test.yml

@@ -12,7 +12,7 @@ jobs:
     strategy:
       max-parallel: 10
       matrix:
-        python_version: ['3.10', '3.12']
+        python_version: ['3.11', '3.14']
 
     steps:
       - uses: actions/checkout@v7

.github/workflows/test.yml

@@ -32,7 +32,7 @@ jobs:
     # Without it, GitHub auto-expands EVERY field of the object-typed
     # `shard` matrix entry — including `shard.paths` — into a
     # >100-character truncated string like
-    # `test (3.13, core, tests/core/models tests/core/graph ...`.
+    # `test (3.14, core, tests/core/models tests/core/graph ...`.
     # That diverges from the short custom status emitted by
     # multi-trigger-setup, forcing branch protection to pick one event
     # type's names and break the others.
@@ -54,7 +54,7 @@ jobs:
       max-parallel: 10
       fail-fast: false
       matrix:
-        python_version: ['3.11', '3.13']
+        python_version: ['3.11', '3.14']
         # tests/perf is run by perf-test.yml on a separate cadence.
         # tests/applications and tests/lammps are run by integration-test.yml
         # and test_lammps_gpu respectively. Both shards below intentionally
@@ -112,7 +112,7 @@ jobs:
             -r tests/requirements.txt # pin test packages
 
       - name: Install torchsim (Python 3.12+)
-        if: ${{ matrix.python_version == '3.12' || matrix.python_version == '3.13' }}
+        if: ${{ matrix.python_version == '3.12' || matrix.python_version == '3.13' || matrix.python_version == '3.14' }}
         run: |
           pip install packages/fairchem-core[torchsim]
 
@@ -145,7 +145,7 @@ jobs:
         run: |
           pytest -m "serial and not gpu" ${{ matrix.shard.paths }} -vv --ignore=tests/demo/ocpapi/tests/integration/ --exclude-models=uma-s-1p1,uma-s-1p2 --cov-report=xml --cov=fairchem --cov-append --junitxml=junit-serial-${{ matrix.shard.name }}.xml -o junit_family=legacy -c ./packages/fairchem-core/pyproject.toml --suppress-no-test-exit-code
 
-      - if: ${{ matrix.python_version == '3.13' }}
+      - if: ${{ matrix.python_version == '3.14' }}
         name: codecov-coverage
         uses: codecov/codecov-action@v7
         with:
@@ -154,7 +154,7 @@ jobs:
           token: ${{ secrets.CODECOV_TOKEN }}
           verbose: true
 
-      - if: ${{ matrix.python_version == '3.13' }}
+      - if: ${{ matrix.python_version == '3.14' }}
         name: codecov-test-results
         uses: codecov/test-results-action@v1
         with:
@@ -180,7 +180,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python_version: ['3.13']
+        python_version: ['3.14']
         sweep_model: [uma-s-1p1, uma-s-1p2]
         shard: *cpu_shards
 
@@ -225,7 +225,7 @@ jobs:
             -r tests/requirements.txt # pin test packages
 
       - name: Install torchsim (Python 3.12+)
-        if: ${{ matrix.python_version == '3.12' || matrix.python_version == '3.13' }}
+        if: ${{ matrix.python_version == '3.12' || matrix.python_version == '3.13' || matrix.python_version == '3.14' }}
         run: |
           pip install packages/fairchem-core[torchsim]
 
@@ -285,7 +285,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python_version: ['3.13']
+        python_version: ['3.14']
         # YAML anchor: shard list is reused by test_gpu_sweep below.
         # Do not reorder jobs (the alias must follow the anchor textually).
         shard: &gpu_shards
@@ -327,7 +327,7 @@ jobs:
           -r tests/requirements.txt # pin test packages
 
       - name: Install torchsim (Python 3.12+)
-        if: ${{ matrix.python_version == '3.12' || matrix.python_version == '3.13' }}
+        if: ${{ matrix.python_version == '3.12' || matrix.python_version == '3.13' || matrix.python_version == '3.14' }}
         run: |
           pip install packages/fairchem-core[torchsim]
 
@@ -375,7 +375,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python_version: ['3.13']
+        python_version: ['3.14']
         sweep_model: [uma-s-1p1, uma-s-1p2]
         shard: *gpu_shards
 
@@ -408,7 +408,7 @@ jobs:
           -r tests/requirements.txt # pin test packages
 
       - name: Install torchsim (Python 3.12+)
-        if: ${{ matrix.python_version == '3.12' || matrix.python_version == '3.13' }}
+        if: ${{ matrix.python_version == '3.12' || matrix.python_version == '3.13' || matrix.python_version == '3.14' }}
         run: |
           pip install packages/fairchem-core[torchsim]
 
@@ -450,15 +450,15 @@ jobs:
     strategy:
       max-parallel: 1
       matrix:
-        python_version: ['3.13']
+        python_version: ['3.14']
 
     steps:
       - uses: actions/checkout@v7
       - uses: mamba-org/setup-micromamba@v3
         with:
           generate-run-shell: true # This is the default behavior
           environment-name: test_env # Specifies a new environment to be created
-          create-args: python=3.13 # Specifies packages to install into the new environment
+          create-args: python=3.14 # Specifies packages to install into the new environment
 
       - name: Checkout code
         uses: actions/checkout@v7

packages/fairchem-core/pyproject.toml

@@ -7,7 +7,7 @@ name = "fairchem-core"
 description = "Machine learning models for chemistry and materials science by the FAIR Chemistry team"
 license = {text = "MIT License"}
 dynamic = ["version", "readme"]
-requires-python = ">=3.11, <3.14"
+requires-python = ">=3.11, <3.15"
 dependencies = [
     "torch~=2.13.0",
     "ray[serve]>=2.53.0",

packages/fairchem-lammps/pyproject.toml

@@ -7,7 +7,7 @@ name = "fairchem-lammps"
 description = "Fairchem extension package to use LAMMPs with fairchem models"
 license = {text = "GnuV2 License"}
 dynamic = ["version", "readme"]
-requires-python = ">=3.10,<3.14"
+requires-python = ">=3.10,<3.15"
 dependencies = [
   "fairchem.core>=2.4.0",
 ]

src/fairchem/core/scripts/create_finetune_dataset.py

@@ -35,7 +35,10 @@ def compute_normalizer_and_linear_reference(train_path, num_workers):
     dataset = AseDBDataset({"src": str(train_path)})
 
     sample_indices = random.sample(range(len(dataset)), min(100000, len(dataset)))
-    with mp.Pool(num_workers) as pool:
+    # Python 3.14 changed the POSIX default start method from ``fork`` to
+    # ``forkserver``. These workers rely on inheriting the dataset initialized
+    # above, so keep using ``fork`` explicitly.
+    with mp.get_context("fork").Pool(num_workers) as pool:
         outputs = list(
             tqdm(
                 pool.imap(extract_energy_and_forces, sample_indices),