Add support for overriding shell to execute CUSTOM_INIT_SCRIPT with

Author: hlovdal

CHANGELOG.md

@@ -15,6 +15,8 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 - Added a CI workflow to lint the code base
 - Added a CI workflow to check for spelling errors
 - Added support for `ARDUINO_CI_UNIT_TEST_EXTRA_COMPILER_FLAGS` environment variable.
+- Added support for overriding the shell used to execute `CUSTOM_INIT_SCRIPT`
+  by setting `CUSTOM_INIT_SCRIPT_SHELL` (defaults to `/bin/sh`).
 
 ### Changed
 - We now compile a shared library to be used for each test.

REFERENCE.md

@@ -46,9 +46,11 @@ This allows a file (or glob) pattern to be executed in your tests directory, cre
 
 ### `CUSTOM_INIT_SCRIPT` environment variable
 
-If set, testing will execute (using `/bin/sh`) the script referred to by this
-variable -- relative to the current working directory (i.e. the root directory
-of the library).  The script will _run_ in the Arduino Libraries directory
+If set, testing will execute the script referred to by this variable -- relative
+to the current working directory (i.e. the root directory of the library). By
+default the script will be executed using `/bin/sh` but you can override by
+setting `CUSTOM_INIT_SCRIPT_SHELL` (e.g to `powershell`, `/usr/bin/perl` etc).
+The script will _run_ in the Arduino Libraries directory
 (changing to the Libraries directory, running the script, and returning to the
 individual library root afterward).  This enables use cases like the GitHub
 action to install custom library versions (i.e. a version of a library that

exe/arduino_ci.rb

@@ -60,6 +60,8 @@ def self.parse(options)
         puts "Additionally, the following environment variables control the script:"
         puts " - #{VAR_CUSTOM_INIT_SCRIPT} - if set, this script will be run from the Arduino/libraries directory"
         puts "       prior to any automated library installation or testing (e.g. to install unofficial libraries)"
+        puts " - #{VAR_CUSTOM_INIT_SCRIPT_SHELL} - if set, this will override the"
+        puts "       default shell (/bin/sh) used to execute #{VAR_CUSTOM_INIT_SCRIPT} with."
         puts " - #{VAR_USE_SUBDIR} - if set, the script will install the library from this subdirectory of the cwd"
         puts " - #{VAR_EXPECT_EXAMPLES} - if set, testing will fail if no example sketches are present"
         puts " - #{VAR_EXPECT_UNITTESTS} - if set, testing will fail if no unit tests are present"
@@ -322,16 +324,17 @@ def get_annotated_compilers(config, cpp_library)
 # In this case, the user provided script would fetch a git repo or some other method.
 def perform_custom_initialization()
   script_path = ENV[VAR_CUSTOM_INIT_SCRIPT]
+  script_shell = ENV[VAR_CUSTOM_INIT_SCRIPT + "_SHELL"] || "/bin/sh"
   inform("Environment variable #{VAR_CUSTOM_INIT_SCRIPT}") { "'#{script_path}'" }
   return if script_path.nil?
   return if script_path.empty?
 
   script_pathname = Pathname.getwd + script_path
   assure("Script at #{VAR_CUSTOM_INIT_SCRIPT} exists") { script_pathname.exist? }
 
-  assure_multiline("Running #{script_pathname} with sh in libraries working dir") do
+  assure_multiline("Running #{script_pathname} with #{script_shell} in libraries working dir") do
     Dir.chdir(@backend.lib_dir) do
-      IO.popen(["/bin/sh", script_pathname.to_s], err: [:child, :out]) do |io|
+      IO.popen([script_shell, script_pathname.to_s], err: [:child, :out]) do |io|
         io.each_line { |line| puts "    #{line}" }
       end
     end