Use mamba to install Continuous Integration dependencies (#841)

Specifically using `mambaforge` which is a `miniconda`
replacement that defaults to using the `conda-forge`
channel and `mamba` instead of `conda` by default.

* Set strict channel priority to conda-forge only with no
defaults to see if it speeds up resolver. See also
https://docs.conda.io/projects/conda/en/latest/user-guide/tasks/manage-channels.html#strict-channel-priority

* Use mamba on GMT Dev Tests CI build
* Use mamba in CI docs and Cache Data workflows
* Pin gmt dev version to 6.3 on Windows CI

Co-authored-by: Dongdong Tian <seisman.info@gmail.com>

.github/workflows/cache_data.yaml

@@ -24,17 +24,21 @@ jobs:
           # fecth all history so that setuptools-scm works
           fetch-depth: 0
 
-      # Setup Miniconda
-      - name: Setup Miniconda
+      # Install Mambaforge with conda-forge dependencies
+      - name: Setup Mambaforge
         uses: conda-incubator/setup-miniconda@v2.1.1
         with:
-          channels: conda-forge
-          miniconda-version: "latest"
+          channels: conda-forge,nodefaults
+          channel-priority: strict
+          miniforge-version: latest
+          miniforge-variant: Mambaforge
+          mamba-version: "*"
+          use-mamba: true
 
       # Install GMT and other required dependencies from conda-forge
       - name: Install dependencies
         run: |
-          conda install gmt=6.2.0 \
+          mamba install gmt=6.2.0 \
                         numpy pandas xarray netCDF4 packaging matplotlib
 
       # Install the package that we want to test

.github/workflows/ci_docs.yml

@@ -54,25 +54,29 @@ jobs:
           # fecth all history so that setuptools-scm works
           fetch-depth: 0
 
-      # Setup Miniconda
-      - name: Setup Miniconda
+      # Install Mambaforge with conda-forge dependencies
+      - name: Setup Mambaforge
         uses: conda-incubator/setup-miniconda@v2.1.1
         with:
           activate-environment: pygmt
           python-version: ${{ matrix.python-version }}
-          channels: conda-forge
-          miniconda-version: "latest"
+          channels: conda-forge,nodefaults
+          channel-priority: strict
+          miniforge-version: latest
+          miniforge-variant: Mambaforge
+          mamba-version: "*"
+          use-mamba: true
 
       # Install GMT and other required dependencies from conda-forge
       - name: Install dependencies
         run: |
-          conda install gmt=6.2.0 numpy pandas xarray netCDF4 packaging \
+          mamba install gmt=6.2.0 numpy pandas xarray netCDF4 packaging \
                         ipython make myst-parser geopandas \
                         sphinx sphinx-copybutton sphinx-gallery sphinx_rtd_theme
 
       # Show installed pkg information for postmortem diagnostic
       - name: List installed packages
-        run: conda list
+        run: mamba list
 
       # Download cached remote files (artifacts) from GitHub
       - name: Download remote data from GitHub

.github/workflows/ci_tests.yaml

@@ -77,19 +77,23 @@ jobs:
           # fecth all history so that setuptools-scm works
           fetch-depth: 0
 
-      # Setup Miniconda
-      - name: Setup Miniconda
+      # Install Mambaforge with conda-forge dependencies
+      - name: Setup Mambaforge
         uses: conda-incubator/setup-miniconda@v2.1.1
         with:
           activate-environment: pygmt
           python-version: ${{ matrix.python-version }}
-          channels: conda-forge
-          miniconda-version: "latest"
+          channels: conda-forge,nodefaults
+          channel-priority: strict
+          miniforge-version: latest
+          miniforge-variant: Mambaforge
+          mamba-version: "*"
+          use-mamba: true
 
       # Install GMT and other required dependencies from conda-forge
       - name: Install dependencies
         run: |
-          conda install gmt=6.2.0 numpy=${{ matrix.numpy-version }} \
+          mamba install gmt=6.2.0 numpy=${{ matrix.numpy-version }} \
                         pandas xarray netCDF4 packaging \
                         ${{ matrix.optional-packages }} \
                         coverage[toml] dvc ipython make \
@@ -98,7 +102,7 @@ jobs:
 
       # Show installed pkg information for postmortem diagnostic
       - name: List installed packages
-        run: conda list
+        run: mamba list
 
       # Download cached remote files (artifacts) from GitHub
       - name: Download remote data from GitHub

.github/workflows/ci_tests_dev.yaml

@@ -71,19 +71,23 @@ jobs:
           # fecth all history so that setuptools-scm works
           fetch-depth: 0
 
-      # Setup Miniconda
-      - name: Setup Miniconda
+      # Install Mambaforge with conda-forge dependencies
+      - name: Setup Mambaforge
         uses: conda-incubator/setup-miniconda@v2.1.1
         with:
           activate-environment: pygmt
           python-version: ${{ matrix.python-version }}
-          channels: conda-forge
-          miniconda-version: "latest"
+          channels: conda-forge,nodefaults
+          channel-priority: strict
+          miniforge-version: latest
+          miniforge-variant: Mambaforge
+          mamba-version: "*"
+          use-mamba: true
 
       # Install dependencies from conda-forge
       - name: Install dependencies
         run: |
-          conda install ninja cmake libblas libcblas liblapack fftw gdal geopandas \
+          mamba install ninja cmake libblas libcblas liblapack fftw gdal geopandas \
                         ghostscript libnetcdf hdf5 zlib curl pcre make dvc
           pip install --pre numpy pandas xarray netCDF4 packaging \
                             ipython pytest-cov pytest-mpl pytest>=6.0 sphinx-gallery \
@@ -98,7 +102,7 @@ jobs:
         if: runner.os != 'Windows'
 
       - name: Install GMT dev version from conda-forge (Windows)
-        run: conda install -c conda-forge/label/dev gmt
+        run: mamba install -c conda-forge/label/dev gmt=6.3
         if: runner.os == 'Windows'
 
       # Download cached remote files (artifacts) from GitHub