Sunset Python 3.8 & get rid of explicit typing exports where possible

.github/workflows/pr_dependency_test.yml

@@ -22,7 +22,7 @@ jobs:
       - name: Set up Python
         uses: actions/setup-python@v4
         with:
-          python-version: "3.8"
+          python-version: "3.10"
       - name: Install dependencies
         run: |
           pip install -e .

.github/workflows/pr_tests.yml

@@ -35,7 +35,7 @@ jobs:
       - name: Set up Python
         uses: actions/setup-python@v4
         with:
-          python-version: "3.8"
+          python-version: "3.10"
       - name: Install dependencies
         run: |
           pip install --upgrade pip
@@ -55,7 +55,7 @@ jobs:
       - name: Set up Python
         uses: actions/setup-python@v4
         with:
-          python-version: "3.8"
+          python-version: "3.10"
       - name: Install dependencies
         run: |
           pip install --upgrade pip

.github/workflows/pr_tests_gpu.yml

@@ -36,7 +36,7 @@ jobs:
       - name: Set up Python
         uses: actions/setup-python@v4
         with:
-          python-version: "3.8"
+          python-version: "3.10"
       - name: Install dependencies
         run: |
           pip install --upgrade pip
@@ -56,7 +56,7 @@ jobs:
       - name: Set up Python
         uses: actions/setup-python@v4
         with:
-          python-version: "3.8"
+          python-version: "3.10"
       - name: Install dependencies
         run: |
           pip install --upgrade pip

.github/workflows/pr_torch_dependency_test.yml

@@ -22,7 +22,7 @@ jobs:
       - name: Set up Python
         uses: actions/setup-python@v4
         with:
-          python-version: "3.8"
+          python-version: "3.10"
       - name: Install dependencies
         run: |
           pip install -e .

.github/workflows/pypi_publish.yaml

@@ -47,7 +47,7 @@ jobs:
       - name: Setup Python
         uses: actions/setup-python@v4
         with:
-          python-version: "3.8"
+          python-version: "3.10"
 
       - name: Install dependencies
         run: |

scripts/remove_typing_builtin_imports.py

@@ -0,0 +1,146 @@
+#!/usr/bin/env python3
+"""
+Remove lower-case built-in generics imported from `typing`.
+"""
+
+from __future__ import annotations
+
+import argparse
+import sys
+from pathlib import Path
+from typing import Iterable, Iterator, Sequence
+
+
+try:
+    import libcst as cst
+except ImportError as exc:  # pragma: no cover - dependency guard
+    raise SystemExit("This script requires `libcst`. Install it via `pip install libcst` and retry.") from exc
+
+
+BUILTIN_TYPING_NAMES = frozenset({"callable", "dict", "frozenset", "list", "set", "tuple", "type"})
+
+
+class TypingBuiltinImportRemover(cst.CSTTransformer):
+    def __init__(self) -> None:
+        self.changed = False
+        self.removed: list[str] = []
+        self.warnings: list[str] = []
+
+    def leave_ImportFrom(self, original_node: cst.ImportFrom, updated_node: cst.ImportFrom) -> cst.BaseStatement:
+        module_name = self._module_name(updated_node.module)
+        if module_name != "typing":
+            return updated_node
+
+        names = updated_node.names
+        if isinstance(names, cst.ImportStar):
+            self.warnings.append("encountered `from typing import *` (skipped)")
+            return updated_node
+
+        new_aliases = []
+        removed_here: list[str] = []
+        for alias in names:
+            if isinstance(alias, cst.ImportStar):
+                self.warnings.append("encountered `from typing import *` (skipped)")
+                return updated_node
+            if not isinstance(alias.name, cst.Name):
+                new_aliases.append(alias)
+                continue
+            imported_name = alias.name.value
+            if imported_name in BUILTIN_TYPING_NAMES:
+                removed_here.append(imported_name)
+                continue
+            new_aliases.append(alias)
+
+        if not removed_here:
+            return updated_node
+
+        self.changed = True
+        self.removed.extend(removed_here)
+
+        if not new_aliases:
+            return cst.RemoveFromParent()
+        # Ensure trailing commas are removed.
+        formatted_aliases = []
+        for alias in new_aliases:
+            if alias.comma is not None and alias is new_aliases[-1]:
+                formatted_aliases.append(alias.with_changes(comma=None))
+            else:
+                formatted_aliases.append(alias)
+
+        return updated_node.with_changes(names=tuple(formatted_aliases))
+
+    def _module_name(self, node: cst.BaseExpression | None) -> str | None:
+        if node is None:
+            return None
+        if isinstance(node, cst.Name):
+            return node.value
+        if isinstance(node, cst.Attribute):
+            prefix = self._module_name(node.value)
+            if prefix is None:
+                return node.attr.value
+            return f"{prefix}.{node.attr.value}"
+        return None
+
+
+def iter_python_files(paths: Iterable[Path]) -> Iterator[Path]:
+    for path in paths:
+        if path.is_dir():
+            yield from (p for p in path.rglob("*.py") if not p.name.startswith("."))
+            yield from (p for p in path.rglob("*.pyi") if not p.name.startswith("."))
+        elif path.suffix in {".py", ".pyi"}:
+            yield path
+
+
+def process_file(path: Path, dry_run: bool) -> tuple[bool, TypingBuiltinImportRemover]:
+    source = path.read_text(encoding="utf-8")
+    module = cst.parse_module(source)
+    transformer = TypingBuiltinImportRemover()
+    updated = module.visit(transformer)
+
+    if not transformer.changed or source == updated.code:
+        return False, transformer
+
+    if not dry_run:
+        path.write_text(updated.code, encoding="utf-8")
+    return True, transformer
+
+
+def main(argv: Sequence[str] | None = None) -> int:
+    parser = argparse.ArgumentParser(description="Remove lower-case built-in generics imported from typing.")
+    parser.add_argument(
+        "paths",
+        nargs="*",
+        type=Path,
+        default=[Path("src")],
+        help="Files or directories to rewrite (default: src).",
+    )
+    parser.add_argument(
+        "--dry-run",
+        action="store_true",
+        help="Only report files that would change without writing them.",
+    )
+    args = parser.parse_args(argv)
+
+    files = sorted(set(iter_python_files(args.paths)))
+    if not files:
+        print("No Python files matched the provided paths.", file=sys.stderr)
+        return 1
+
+    changed_any = False
+    for path in files:
+        changed, transformer = process_file(path, dry_run=args.dry_run)
+        if changed:
+            changed_any = True
+            action = "Would update" if args.dry_run else "Updated"
+            removed = ", ".join(sorted(set(transformer.removed)))
+            print(f"{action}: {path} (removed typing imports: {removed})")
+        for warning in transformer.warnings:
+            print(f"Warning: {path}: {warning}", file=sys.stderr)
+
+    if not changed_any:
+        print("No changes needed.")
+    return 0
+
+
+if __name__ == "__main__":
+    raise SystemExit(main())

setup.py

@@ -122,7 +122,7 @@
     "pytest",
     "pytest-timeout",
     "pytest-xdist",
-    "python>=3.8.0",
+    "python>=3.9.0",
     "ruff==0.9.10",
     "safetensors>=0.3.1",
     "sentencepiece>=0.1.91,!=0.1.92",
@@ -287,7 +287,7 @@ def run(self):
     packages=find_packages("src"),
     package_data={"diffusers": ["py.typed"]},
     include_package_data=True,
-    python_requires=">=3.8.0",
+    python_requires=">=3.9.0",
     install_requires=list(install_requires),
     extras_require=extras,
     entry_points={"console_scripts": ["diffusers-cli=diffusers.commands.diffusers_cli:main"]},

src/diffusers/callbacks.py

@@ -1,4 +1,4 @@
-from typing import Any, Dict, List
+from typing import Any
 
 from .configuration_utils import ConfigMixin, register_to_config
 from .utils import CONFIG_NAME
@@ -33,13 +33,13 @@ def __init__(self, cutoff_step_ratio=1.0, cutoff_step_index=None):
             raise ValueError("cutoff_step_ratio must be a float between 0.0 and 1.0.")
 
     @property
-    def tensor_inputs(self) -> List[str]:
+    def tensor_inputs(self) -> list[str]:
         raise NotImplementedError(f"You need to set the attribute `tensor_inputs` for {self.__class__}")
 
-    def callback_fn(self, pipeline, step_index, timesteps, callback_kwargs) -> Dict[str, Any]:
+    def callback_fn(self, pipeline, step_index, timesteps, callback_kwargs) -> dict[str, Any]:
         raise NotImplementedError(f"You need to implement the method `callback_fn` for {self.__class__}")
 
-    def __call__(self, pipeline, step_index, timestep, callback_kwargs) -> Dict[str, Any]:
+    def __call__(self, pipeline, step_index, timestep, callback_kwargs) -> dict[str, Any]:
         return self.callback_fn(pipeline, step_index, timestep, callback_kwargs)
 
 
@@ -49,14 +49,14 @@ class MultiPipelineCallbacks:
     provides a unified interface for calling all of them.
     """
 
-    def __init__(self, callbacks: List[PipelineCallback]):
+    def __init__(self, callbacks: list[PipelineCallback]):
         self.callbacks = callbacks
 
     @property
-    def tensor_inputs(self) -> List[str]:
+    def tensor_inputs(self) -> list[str]:
         return [input for callback in self.callbacks for input in callback.tensor_inputs]
 
-    def __call__(self, pipeline, step_index, timestep, callback_kwargs) -> Dict[str, Any]:
+    def __call__(self, pipeline, step_index, timestep, callback_kwargs) -> dict[str, Any]:
         """
         Calls all the callbacks in order with the given arguments and returns the final callback_kwargs.
         """
@@ -76,7 +76,7 @@ class SDCFGCutoffCallback(PipelineCallback):
 
     tensor_inputs = ["prompt_embeds"]
 
-    def callback_fn(self, pipeline, step_index, timestep, callback_kwargs) -> Dict[str, Any]:
+    def callback_fn(self, pipeline, step_index, timestep, callback_kwargs) -> dict[str, Any]:
         cutoff_step_ratio = self.config.cutoff_step_ratio
         cutoff_step_index = self.config.cutoff_step_index
 
@@ -109,7 +109,7 @@ class SDXLCFGCutoffCallback(PipelineCallback):
         "add_time_ids",
     ]
 
-    def callback_fn(self, pipeline, step_index, timestep, callback_kwargs) -> Dict[str, Any]:
+    def callback_fn(self, pipeline, step_index, timestep, callback_kwargs) -> dict[str, Any]:
         cutoff_step_ratio = self.config.cutoff_step_ratio
         cutoff_step_index = self.config.cutoff_step_index
 
@@ -152,7 +152,7 @@ class SDXLControlnetCFGCutoffCallback(PipelineCallback):
         "image",
     ]
 
-    def callback_fn(self, pipeline, step_index, timestep, callback_kwargs) -> Dict[str, Any]:
+    def callback_fn(self, pipeline, step_index, timestep, callback_kwargs) -> dict[str, Any]:
         cutoff_step_ratio = self.config.cutoff_step_ratio
         cutoff_step_index = self.config.cutoff_step_index
 
@@ -195,7 +195,7 @@ class IPAdapterScaleCutoffCallback(PipelineCallback):
 
     tensor_inputs = []
 
-    def callback_fn(self, pipeline, step_index, timestep, callback_kwargs) -> Dict[str, Any]:
+    def callback_fn(self, pipeline, step_index, timestep, callback_kwargs) -> dict[str, Any]:
         cutoff_step_ratio = self.config.cutoff_step_ratio
         cutoff_step_index = self.config.cutoff_step_index
 
@@ -219,7 +219,7 @@ class SD3CFGCutoffCallback(PipelineCallback):
 
     tensor_inputs = ["prompt_embeds", "pooled_prompt_embeds"]
 
-    def callback_fn(self, pipeline, step_index, timestep, callback_kwargs) -> Dict[str, Any]:
+    def callback_fn(self, pipeline, step_index, timestep, callback_kwargs) -> dict[str, Any]:
         cutoff_step_ratio = self.config.cutoff_step_ratio
         cutoff_step_index = self.config.cutoff_step_index