add environment files

.ci/conda-envs/ci-core-py37.txt

@@ -0,0 +1,56 @@
+# [description]
+#
+#   Similar to ci-core.txt, but specific to Python 3.7.
+#
+#   Unlike ci-core.txt, this includes a Python version and uses
+#   `=` and `<=` pins to make solves faster and prevent against
+#   issues like https://github.com/microsoft/LightGBM/pull/6370.
+#
+# [usage]
+#
+#   conda create \
+#     --name test-env \
+#     --file ./.ci/conda-envs/ci-core-py37.txt
+#
+
+# python
+python=3.7.12
+
+# direct imports
+cffi=1.15.*
+# older versions of Dask are incompatible with pandas>=2.0, but not all conda packages' metadata accurately reflects that
+#
+# ref: https://github.com/microsoft/LightGBM/issues/6030
+dask=2022.2.*
+distributed=2022.2.*
+joblib=1.3.*
+matplotlib-base=3.5.*
+numpy=1.21.*
+pandas=1.3.*
+pyarrow=9.0.*
+# python-graphviz 0.20.2 is not compatible with Python 3.7
+# ref: https://github.com/microsoft/LightGBM/pull/6370
+python-graphviz=0.20.1
+scikit-learn=1.0.*
+scipy=1.7.*
+
+# testing-only dependencies
+cloudpickle=2.2.*
+pluggy=1.0.*
+psutil=5.9.3
+pytest=7.4.*
+
+# other recursive dependencies, just
+# pinned here to help speed up solves
+bokeh=2.4.*
+fsspec=2023.1.*
+msgpack-python=1.0.*
+pluggy=1.0.*
+pytz=2024.1
+setuptools=59.8.*
+snappy=1.1.*
+tomli=2.0.*
+tornado=6.1.*
+wheel=0.43.*
+zict=2.2.*
+zipp=3.15.*

.ci/conda-envs/ci-core.txt

@@ -0,0 +1,40 @@
+# [description]
+#
+#   Core dependencies used across most LightGBM continuous integration (CI) jobs.
+#
+#   'python' constraint is intentionally omitted, so this file can be reused across
+#   Python versions.
+#
+#   These floors are not the oldest versions LightGBM supports... they're here just to make conda
+#   solves faster, and should generally be the latest versions that work for all CI jobs using this.
+#
+# [usage]
+#
+#   conda create \
+#     --name test-env \
+#     --file ./.ci/conda-envs/ci-core.txt \
+#     python=3.10
+#
+
+# direct imports
+conda-forge::cffi>=1.16
+dask>=2023.5.0
+joblib>=1.3.2
+matplotlib-base>=3.7.3
+numpy>=1.24.4
+pandas>2.0
+pyarrow>=6.0
+python-graphviz>=0.20.3
+scikit-learn>=1.3.2
+scipy>=1.1
+
+# testing-only dependencies
+cloudpickle>=3.0.0
+psutil>=5.9.8
+pytest>=8.1.1
+
+# other recursive dependencies, just
+# pinned here to help speed up solves
+pluggy>=1.4.0
+setuptools>=69.2
+wheel>=0.43

.ci/test.sh

@@ -36,6 +36,7 @@ if [[ "$TASK" == "cpp-tests" ]]; then
     exit 0
 fi
 
+# including python=version[build=*cpython] to ensure that conda doesn't fall back to pypy
 CONDA_PYTHON_REQUIREMENT="python=$PYTHON_VERSION[build=*cpython]"
 
 if [[ $TASK == "if-else" ]]; then
@@ -121,32 +122,18 @@ if [[ $TASK == "check-docs" ]] || [[ $TASK == "check-links" ]]; then
     exit 0
 fi
 
-# older versions of Dask are incompatible with pandas>=2.0, but not all conda packages' metadata accurately reflects that
-#
-# ref: https://github.com/microsoft/LightGBM/issues/6030
-CONSTRAINED_DEPENDENCIES="'dask>=2023.5.0' 'distributed>=2023.5.0' 'pandas>=2.0' 'python-graphviz>=0.20'"
 if [[ $PYTHON_VERSION == "3.7" ]]; then
-    CONSTRAINED_DEPENDENCIES="'dask' 'distributed' 'python-graphviz<0.20.2' 'pandas<2.0'"
+    CONDA_REQUIREMENT_FILES="--file ${BUILD_DIRECTORY}/.ci/conda-envs/ci-core-py37.txt"
+else
+    CONDA_REQUIREMENT_FILES="--file ${BUILD_DIRECTORY}/.ci/conda-envs/ci-core.txt"
 fi
 
-# notes:
-#   * including python=version[build=*cpython] to ensure that conda doesn't fall back to pypy
-#   * these floors are not the oldest versions LightGBM supports... they're here just to make conda
-#     solves faster, and should generally be the latest versions that work for all CI jobs using
-#     this script
-mamba create -y -n $CONDA_ENV \
-    ${CONSTRAINED_DEPENDENCIES} \
-    'cffi>=1.16' \
-    'cloudpickle>=3.0.0' \
-    'joblib>=1.3.2' \
-    'matplotlib-base>=3.7.3' \
-    'numpy>=1.24.4' \
-    'psutil>=5.9.8' \
-    'pyarrow>=6.0' \
-    'pytest>=8.1.1' \
+mamba create \
+    -y \
+    -n $CONDA_ENV \
+    ${CONDA_REQUIREMENT_FILES} \
     ${CONDA_PYTHON_REQUIREMENT} \
-    'scikit-learn>=1.3.2' \
-    'scipy>=1.10' || exit 1
+|| exit 1
 
 source activate $CONDA_ENV
 

.ci/test_windows.ps1

@@ -49,20 +49,19 @@ conda config --set always_yes yes --set changeps1 no
 conda install "brotlipy>=0.7"
 
 conda update -q -y conda
-conda create -y -n $env:CONDA_ENV `
-  "cffi>=1.16" `
-  "cloudpickle>=3.0" `
-  "joblib>=1.3.2" `
-  "matplotlib-base>=3.7.3" `
-  "numpy>=1.24.4" `
-  "pandas>=1.5" `
-  "psutil>=5.9.8" `
-  "pyarrow>=12.0" `
-  "pytest>=8.1.1" `
+
+if ($env:PYTHON_VERSION -eq "3.7") {
+  $env:CONDA_REQUIREMENT_FILES = "--file $env:BUILD_SOURCESDIRECTORY/.ci/ci-core-py37.txt"
+} else {
+  $env:CONDA_REQUIREMENT_FILES = "--file $env:BUILD_SOURCESDIRECTORY/.ci/ci-core.txt"
+}
+
+conda create `
+  -y  
+  -n $env:CONDA_ENV `
+  $env:CONDA_REQUIREMENT_FILES `
   "python=$env:PYTHON_VERSION[build=*cpython]" `
-  "python-graphviz>=0.20" `
-  "scikit-learn>=1.3.2" `
-  "scipy>=1.10" ; Check-Output $?
+; Check-Output $?
 
 if ($env:TASK -ne "bdist") {
   conda activate $env:CONDA_ENV