Test setting symlink type via CYGWIN env var

.github/workflows/test.yml

@@ -114,7 +114,7 @@ jobs:
       with:
         install-dir: "${{ matrix.install-dir }}"
 
-    - name: Check working directory
+    - name: Check install directory
       run: |
         if [[ "$(cygpath -aw /)" == '${{ matrix.install-dir }}' ]]; then
           echo "Installed in $(cygpath -aw /)"
@@ -133,6 +133,31 @@ jobs:
       env:
         SHELLOPTS: igncr
 
+  symlink-test:
+    runs-on: windows-latest
+    name: 'Check symlink type control'
+
+    strategy:
+      matrix:
+        include:
+          - symlink-type: native
+          - symlink-type: sys
+          - symlink-type: wsl
+
+    env:
+      CYGWIN: winsymlinks:${{ matrix.symlink-type }}
+
+    steps:
+    - run: git config --global core.autocrlf input
+
+    - uses: actions/checkout@v2
+
+    - name: Install Cygwin
+      uses: ./
+
+    - name: Check symlink
+      run: bash tests/symlink.sh
+
   time-machine:
     runs-on: windows-latest
     strategy:

README.md

@@ -72,13 +72,16 @@ or,
 Symlinks
 --------
 
-Unfortunately, Cygwin's `setup` doesn't (currently) honour
-`CYGWIN=winsymlinks:native` or offer an option to control the kind of symlinks
-created, so some executables (e.g. `python`) are created as Cygwin-style
-symlinks. Since CMD and PowerShell don't understand those symlinks, you cannot
-run those executables directly in a `run:` in your workflow. Execute them via
+Cygwin's `setup` creates Cygwin-style symlinks by default, and some
+executables (e.g. `python`) are symlinks.
+
+Since CMD and PowerShell don't understand those symlinks, you cannot run
+those executables directly in a `run:` in your workflow. Execute them via
 `bash` or `env` instead.
 
+Alternatively, putting e.g. `CYGWIN=winsymlinks:native` into the workflow's
+environment works, since setup now honours that.
+
 Mirrors and signatures
 ----------------------
 

tests/symlink.sh

@@ -0,0 +1,27 @@
+#!/usr/bin/bash
+
+TEST_FILE="/usr/bin/apropos"
+echo "cygpath -w ${TEST_FILE} returns $(cygpath -w ${TEST_FILE})"
+# don't convert using cygpath -w, as that canonicalizes symlinks ?!?
+TEST_FILE_W="C:\cygwin\bin\apropos"
+
+# check the symlink we're going to do checks on exists
+if [ ! -L ${TEST_FILE} ]; then
+  echo "This test assumes ${TEST_FILE} exists and is a symlink"
+  exit 1
+fi
+
+# check the symlink was created in the way expected
+case ${CYGWIN} in
+  *sys*)
+    cmd /c "dir /AS ${TEST_FILE_W}" | grep "21"
+    ;;
+
+  *native*)
+    cmd /c "dir /AL ${TEST_FILE_W}" | grep "<SYMLINK>"
+    ;;
+
+  *wsl*)
+    fsutil reparsepoint query ${TEST_FILE_W} | grep "0xa000001d"
+    ;;
+esac