From 59a561deda8f3b0eb01bc6f9d6f4a2344ba541b8 Mon Sep 17 00:00:00 2001
From: Aarni Koskela <akx@iki.fi>
Date: Tue, 26 Sep 2023 20:15:12 +0300
Subject: [PATCH 1/8] Drop support for Pythons older than 3.8

---
 .github/workflows/run_tests.yml | 2 +-
 README.md                       | 2 +-
 setup.py                        | 8 +++-----
 3 files changed, 5 insertions(+), 7 deletions(-)

diff --git a/.github/workflows/run_tests.yml b/.github/workflows/run_tests.yml
index e63c1e7..5c57e4f 100644
--- a/.github/workflows/run_tests.yml
+++ b/.github/workflows/run_tests.yml
@@ -54,7 +54,7 @@ jobs:
     needs: [ check_version ]
     strategy:
       matrix:
-        python-version: [ 3.6, 3.8 ]
+        python-version: [ 3.8 ]
         os: [ ubuntu-latest, macOS-latest, windows-latest ]
       fail-fast: false
     runs-on: ${{ matrix.os }}
diff --git a/README.md b/README.md
index 767a95f..84f9827 100644
--- a/README.md
+++ b/README.md
@@ -11,7 +11,7 @@ This library provides [stochastic differential equation (SDE)](https://en.wikipe
 pip install torchsde
 ```
 
-**Requirements:** Python >=3.6 and PyTorch >=1.6.0.
+**Requirements:** Python >=3.8 and PyTorch >=1.6.0.
 
 ## Documentation
 Available [here](./DOCUMENTATION.md).
diff --git a/setup.py b/setup.py
index 23e873a..5bd16bc 100644
--- a/setup.py
+++ b/setup.py
@@ -41,14 +41,12 @@
     packages=setuptools.find_packages(exclude=['benchmarks', 'diagnostics', 'examples', 'tests']),
     install_requires=[
         "boltons>=20.2.1",
-        "numpy==1.19;python_version<'3.7'",
-        "numpy>=1.19;python_version>='3.7'",
-        "scipy==1.5;python_version<'3.7'",
-        "scipy>=1.5;python_version>='3.7'",
+        "numpy>=1.19",
+        "scipy>=1.5",
         "torch>=1.6.0",
         "trampoline>=0.1.2",
     ],
-    python_requires='~=3.6',
+    python_requires='>=3.8',
     classifiers=[
         "Programming Language :: Python :: 3",
         "License :: OSI Approved :: Apache Software License",

From 7f2ef817184838aad43cc188a7aee075fb2c22c1 Mon Sep 17 00:00:00 2001
From: Aarni Koskela <akx@iki.fi>
Date: Tue, 26 Sep 2023 20:16:26 +0300
Subject: [PATCH 2/8] Remove 2020-era Windows patch from CI

---
 .github/workflows/run_tests.yml | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/.github/workflows/run_tests.yml b/.github/workflows/run_tests.yml
index 5c57e4f..ee0711c 100644
--- a/.github/workflows/run_tests.yml
+++ b/.github/workflows/run_tests.yml
@@ -72,10 +72,6 @@ jobs:
           python -m pip install --upgrade pip
           python -m pip install flake8 pytest
 
-      - name: Windows patch  # Specifically for windows, since pip fails to fetch torch 1.6.0 as of Oct 2020.
-        if: runner.os == 'Windows'
-        run: python -m pip install torch==1.6.0+cpu torchvision==0.7.0+cpu -f https://download.pytorch.org/whl/torch_stable.html
-
       - name: Lint with flake8
         run: |
           python -m flake8 .

From 4746fc848c5bdc8b730a38419ab75ab395c20909 Mon Sep 17 00:00:00 2001
From: Aarni Koskela <akx@iki.fi>
Date: Tue, 26 Sep 2023 20:17:31 +0300
Subject: [PATCH 3/8] Remove baroque check_version step from CI

---
 .github/workflows/run_tests.yml | 42 ---------------------------------
 1 file changed, 42 deletions(-)

diff --git a/.github/workflows/run_tests.yml b/.github/workflows/run_tests.yml
index ee0711c..4bc1ecf 100644
--- a/.github/workflows/run_tests.yml
+++ b/.github/workflows/run_tests.yml
@@ -9,49 +9,7 @@ on:
     - cron: "0 2 * * 6"
 
 jobs:
-  check_version:
-    strategy:
-      matrix:
-        python-version: [ 3.8 ]
-        os: [ ubuntu-latest ]
-    runs-on: ${{ matrix.os }}
-    steps:
-      - name: Checkout code
-        uses: actions/checkout@v2
-
-      - name: Set up Python ${{ matrix.python-version }}
-        uses: actions/setup-python@v2
-        with:
-          python-version: ${{ matrix.python-version }}
-
-      - name: Check version
-        if: (github.event_name == 'pull_request' && github.base_ref == 'master')
-        run: |
-          python -m pip install --upgrade pip
-
-          python -m pip install git+https://github.com/google-research/torchsde.git
-          master_info=$(pip list | grep torchsde)
-          master_version=$(echo ${master_info} | cut -d " " -f2)
-          python -m pip uninstall -y torchsde
-
-          python setup.py install
-          pr_info=$(pip list | grep torchsde)
-          pr_version=$(echo ${pr_info} | cut -d " " -f2)
-
-          python -c "import itertools as it
-          import sys
-
-          _, master_version, pr_version = sys.argv
-
-          master_version_ = [int(i) for i in master_version.split('.')]
-          pr_version_ = [int(i) for i in pr_version.split('.')]
-
-          master_version__ = tuple(m for p, m in it.zip_longest(pr_version_, master_version_, fillvalue=0))
-          pr_version__ = tuple(p for p, m in it.zip_longest(pr_version_, master_version_, fillvalue=0))
-          sys.exit(pr_version__ < master_version__)" ${master_version} ${pr_version}
-
   build:
-    needs: [ check_version ]
     strategy:
       matrix:
         python-version: [ 3.8 ]

From 529de6cc1b7fdea2feb4091cf80c1ae92a4592a5 Mon Sep 17 00:00:00 2001
From: Aarni Koskela <akx@iki.fi>
Date: Tue, 26 Sep 2023 20:19:39 +0300
Subject: [PATCH 4/8] CI: renovate, add pip cache

---
 .github/workflows/run_tests.yml | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/.github/workflows/run_tests.yml b/.github/workflows/run_tests.yml
index 4bc1ecf..14a3539 100644
--- a/.github/workflows/run_tests.yml
+++ b/.github/workflows/run_tests.yml
@@ -18,12 +18,14 @@ jobs:
     runs-on: ${{ matrix.os }}
     steps:
       - name: Checkout code
-        uses: actions/checkout@v2
+        uses: actions/checkout@v4
 
       - name: Set up Python ${{ matrix.python-version }}
-        uses: actions/setup-python@v2
+        uses: actions/setup-python@v4
         with:
           python-version: ${{ matrix.python-version }}
+          cache: pip
+          cache-dependency-path: setup.py
 
       - name: Install dependencies
         run: |

From ad784129a3ec31d865eadb5245e2966873d6862f Mon Sep 17 00:00:00 2001
From: Aarni Koskela <akx@iki.fi>
Date: Tue, 26 Sep 2023 20:32:11 +0300
Subject: [PATCH 5/8] CI: split linting to separate step

---
 .github/workflows/run_tests.yml | 27 ++++++++++++++++++---------
 1 file changed, 18 insertions(+), 9 deletions(-)

diff --git a/.github/workflows/run_tests.yml b/.github/workflows/run_tests.yml
index 14a3539..71bbea2 100644
--- a/.github/workflows/run_tests.yml
+++ b/.github/workflows/run_tests.yml
@@ -27,16 +27,25 @@ jobs:
           cache: pip
           cache-dependency-path: setup.py
 
-      - name: Install dependencies
-        run: |
-          python -m pip install --upgrade pip
-          python -m pip install flake8 pytest
+      - name: Install
+        run: pip install pytest -e .
+
+      - name: Test with pytest
+        run: python -m pytest
+
+  lint:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+
+      - uses: actions/setup-python@v4
+        with:
+          python-version: "3.11"
+          cache: pip
+          cache-dependency-path: setup.py
 
       - name: Lint with flake8
         run: |
+          python -m pip install flake8
           python -m flake8 .
-
-      - name: Test with pytest
-        run: |
-          python setup.py install
-          python -m pytest

From 6af010fed81625a7420e2abb4d95c7ea71664bda Mon Sep 17 00:00:00 2001
From: Aarni Koskela <akx@iki.fi>
Date: Tue, 26 Sep 2023 20:32:42 +0300
Subject: [PATCH 6/8] CI: don't allow compiling libraries from scratch, use
 correct Torch repo

---
 .github/workflows/run_tests.yml | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/.github/workflows/run_tests.yml b/.github/workflows/run_tests.yml
index 71bbea2..cce7b27 100644
--- a/.github/workflows/run_tests.yml
+++ b/.github/workflows/run_tests.yml
@@ -28,7 +28,9 @@ jobs:
           cache-dependency-path: setup.py
 
       - name: Install
-        run: pip install pytest -e .
+        run: pip install pytest -e . --only-binary=numpy,scipy,matplotlib,torch
+        env:
+          PIP_EXTRA_INDEX_URL: https://download.pytorch.org/whl/cpu
 
       - name: Test with pytest
         run: python -m pytest

From 9996af12c60989628d874b75d5efd154d16a3a0c Mon Sep 17 00:00:00 2001
From: Aarni Koskela <akx@iki.fi>
Date: Tue, 26 Sep 2023 20:33:12 +0300
Subject: [PATCH 7/8] CI: print pytest progress

---
 .github/workflows/run_tests.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.github/workflows/run_tests.yml b/.github/workflows/run_tests.yml
index cce7b27..9e979ea 100644
--- a/.github/workflows/run_tests.yml
+++ b/.github/workflows/run_tests.yml
@@ -33,7 +33,7 @@ jobs:
           PIP_EXTRA_INDEX_URL: https://download.pytorch.org/whl/cpu
 
       - name: Test with pytest
-        run: python -m pytest
+        run: python -m pytest -v
 
   lint:
     runs-on: ubuntu-latest

From 9985de795e2438c0ad30b70ee97e720fb5f77f1d Mon Sep 17 00:00:00 2001
From: Aarni Koskela <akx@iki.fi>
Date: Tue, 26 Sep 2023 20:30:25 +0300
Subject: [PATCH 8/8] Drop Boltons dependency for small custom LRU dict

---
 setup.py                                |  1 -
 torchsde/_brownian/brownian_interval.py | 18 ++++++++++++++++--
 2 files changed, 16 insertions(+), 3 deletions(-)

diff --git a/setup.py b/setup.py
index 5bd16bc..66f3d1f 100644
--- a/setup.py
+++ b/setup.py
@@ -40,7 +40,6 @@
     url="https://github.com/google-research/torchsde",
     packages=setuptools.find_packages(exclude=['benchmarks', 'diagnostics', 'examples', 'tests']),
     install_requires=[
-        "boltons>=20.2.1",
         "numpy>=1.19",
         "scipy>=1.5",
         "torch>=1.6.0",
diff --git a/torchsde/_brownian/brownian_interval.py b/torchsde/_brownian/brownian_interval.py
index afde9cb..79391d2 100644
--- a/torchsde/_brownian/brownian_interval.py
+++ b/torchsde/_brownian/brownian_interval.py
@@ -16,7 +16,6 @@
 import trampoline
 import warnings
 
-import boltons.cacheutils
 import numpy as np
 import torch
 
@@ -112,6 +111,21 @@ def __getitem__(self, item):
         raise KeyError
 
 
+class _LRUDict(dict):
+    def __init__(self, max_size):
+        super().__init__()
+        self._max_size = max_size
+        self._keys = []
+
+    def __setitem__(self, key, value):
+        if key in self:
+            self._keys.remove(key)
+        elif len(self) >= self._max_size:
+            del self[self._keys.pop(0)]
+        super().__setitem__(key, value)
+        self._keys.append(key)
+
+
 class _Interval:
     # Intervals correspond to some subinterval of the overall interval [t0, t1].
     # They are arranged as a binary tree: each node corresponds to an interval. If a node has children, they are left
@@ -505,7 +519,7 @@ def __init__(self,
         elif cache_size == 0:
             self._increment_and_space_time_levy_area_cache = _EmptyDict()
         else:
-            self._increment_and_space_time_levy_area_cache = boltons.cacheutils.LRU(max_size=cache_size)
+            self._increment_and_space_time_levy_area_cache = _LRUDict(max_size=cache_size)
 
         # We keep track of the most recently queried interval, and start searching for the next interval from that
         # element of the binary tree. This is because subsequent queries are likely to be near the most recent query.