Allow testing from a subdirectory during CI testing

Author: ianfixes

CHANGELOG.md

@@ -8,6 +8,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 ## [Unreleased]
 ### Added
 - Environment variable to run a custom initialization script during CI testing: `CUSTOM_INIT_SCRIPT`
+- Environment variable to run from a subdirectory during CI testing: `USE_SUBDIR`
 
 ### Changed
 

REFERENCE.md

@@ -44,6 +44,11 @@ This allows a file (or glob) pattern to be executed in your tests directory, cre
 If set, testing will execute (using `/bin/sh`) the script referred to by this variable -- relative to the current working directory.  This enables use cases like the GitHub action to install custom library versions (i.e. a version of a library that is different than what the library manager would automatically install by name) prior to CI test runs.
 
 
+### `USE_SUBDIR` environment variable
+
+If set, testing will be conducted in this subdirectory (relative to the working directory).  This is for monorepos or other layouts where the library directory and project root directory are different.
+
+
 ### `EXPECT_UNITTESTS` environment variable
 
 If set, testing will fail if no unit test files are detected (or if the directory does not exist).  This is to avoid communicating a passing status in cases where a commit may have accidentally moved or deleted the test files.

exe/arduino_ci.rb

@@ -6,6 +6,7 @@
 
 WIDTH = 80
 VAR_CUSTOM_INIT_SCRIPT = "CUSTOM_INIT_SCRIPT".freeze
+VAR_USE_SUBDIR         = "USE_SUBDIR".freeze
 VAR_EXPECT_EXAMPLES    = "EXPECT_EXAMPLES".freeze
 VAR_EXPECT_UNITTESTS   = "EXPECT_UNITTESTS".freeze
 
@@ -54,6 +55,7 @@ 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 unoffical libraries)"
+        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"
         exit
@@ -424,8 +426,10 @@ def perform_example_compilation_tests(cpp_library, config)
 # run any library init scripts from the library itself.
 perform_custom_initialization(config)
 
+
 # initialize library under test
-cpp_library_path = Pathname.new(".")
+inform("Environment variable #{VAR_USE_SUBDIR}") { "'#{ENV[VAR_USE_SUBDIR]}'" }
+cpp_library_path = Pathname.new(ENV[VAR_USE_SUBDIR].nil? ? "." : ENV[VAR_USE_SUBDIR])
 cpp_library = assure("Installing library under test") do
   @backend.install_local_library(cpp_library_path)
 end