Set miniconda env variable in matrix

Author: juliasilge

.github/workflows/R-CMD-check.yaml

@@ -18,8 +18,8 @@ jobs:
       fail-fast: false
       matrix:
         config:
-          - {os: macOS-latest,   r: 'devel'}
-          - {os: macOS-latest,   r: 'release'}
+          - {os: macOS-latest,   r: 'devel',   miniconda: 'miniconda/'}
+          - {os: macOS-latest,   r: 'release', miniconda: 'miniconda/'}
           - {os: windows-latest, r: 'release'}
           - {os: windows-latest, r: '3.6'}
           - {os: ubuntu-16.04,   r: 'release', rspm: "https://packagemanager.rstudio.com/cran/__linux__/xenial/latest"}
@@ -30,6 +30,7 @@ jobs:
       R_REMOTES_NO_ERRORS_FROM_WARNINGS: true
       RSPM: ${{ matrix.config.rspm }}
       GITHUB_PAT: ${{ secrets.GITHUB_TOKEN }}
+      RETICULATE_MINICONDA_PATH: ${{ matrix.config.miniconda }}
 
     steps:
       - uses: actions/checkout@v2
@@ -70,21 +71,21 @@ jobs:
           remotes::install_cran("rcmdcheck")
         shell: Rscript {0}
 
-      - name: Install TensorFlow on macOS and Ubuntu
-        if: runner.os != 'Windows'
-        env:
-          RETICULATE_MINICONDA_PATH: 'miniconda/'
+      - name: Install TensorFlow on macOS
+        if: runner.os == 'macOS'
         run: |
-          Rscript -e "reticulate::install_miniconda()"
-          Rscript -e "reticulate::conda_create('r-reticulate', packages = 'python==3.6.9', conda = 'miniconda/bin/conda')"
-          Rscript -e "tensorflow::install_tensorflow(version='1.14.0', conda = 'miniconda/bin/conda')"
+          reticulate::install_miniconda()
+          reticulate::conda_create('r-reticulate', packages = 'python==3.6.9', conda = 'miniconda/bin/conda')
+          tensorflow::install_tensorflow(version='1.14.0', conda = 'miniconda/bin/conda')
+        shell: Rscript {0}
 
-      - name: Install TensorFlow on Windows
-        if: runner.os == 'Windows'
+      - name: Install TensorFlow on Ubuntu and Windows
+        if: runner.os != 'macOS'
         run: |
-          Rscript -e "reticulate::install_miniconda()"
-          Rscript -e "reticulate::conda_create('r-reticulate', packages = 'python==3.6.9')"
-          Rscript -e "tensorflow::install_tensorflow(version='1.14.0')"
+          reticulate::install_miniconda()
+          reticulate::conda_create('r-reticulate', packages = 'python==3.6.9')
+          tensorflow::install_tensorflow(version='1.14.0')
+        shell: Rscript {0}
 
       - name: Session info
         run: |