Allow running Java+Ruby tests on Windows separately (#15861)

This commit allows separate running of Java and Ruby tests on Windows i.e. the same way as we currently do on unix (unit_tests.sh) via a cli argument.
If no argument has been supplied, both tests are run (as it does now).

The wrapper script is also rewritten from old batch style script to Powershell.

This work allows us to split the existing Windows CI job in a subsequent PR to separate steps, as we currently do on Linux.

Relates: #15566

.buildkite/scripts/exhaustive-tests/generate-steps.py

@@ -38,7 +38,7 @@ def compat_linux_step(imagesuffix: str) -> dict[str, typing.Any]:
 
 
 def compat_windows_step(imagesuffix: str) -> dict[str, typing.Any]:
-    windows_command = LiteralScalarString(r'''$$env:WORKSPACE=$$PWD.Path ; .\\ci\\unit_tests.bat''')
+    windows_command = LiteralScalarString(r'''.\\ci\\unit_tests.ps1''')
 
     return compat_step(imagesuffix, command=windows_command)
 

.buildkite/scripts/jdk-matrix-tests/generate-steps.py

@@ -141,7 +141,7 @@ def all_jobs(self) -> list[typing.Callable[[], JobRetValues]]:
     def unit_tests(self) -> JobRetValues:
         step_name_human = "Unit Test (Java/Ruby)"
         step_key = f"{self.group_key}-unit-test"
-        test_command = rf'''.\\.buildkite\\scripts\\jdk-matrix-tests\\launch-command.ps1 -JDK "{self.jdk}" -StepNameHuman "{step_name_human}" -AnnotateContext "{self.group_key}" -CIScript ".\\ci\\unit_tests.bat" -Annotate
+        test_command = rf'''.\\.buildkite\\scripts\\jdk-matrix-tests\\launch-command.ps1 -JDK "{self.jdk}" -StepNameHuman "{step_name_human}" -AnnotateContext "{self.group_key}" -CIScript ".\\ci\\unit_tests.ps1" -Annotate
         '''
 
         return JobRetValues(

.buildkite/scripts/jdk-matrix-tests/launch-command.ps1

@@ -14,9 +14,6 @@ param (
 # expand previous buildkite folded section (command invocation)
 Write-Host "^^^ +++"
 
-# the unit test script expects the WORKSPACE env var
-$env:WORKSPACE = $PWD.Path
-
 # unset generic JAVA_HOME
 if (Test-Path env:JAVA_HOME) {
     Remove-Item -Path env:JAVA_HOME

ci/unit_tests.ps1

@@ -0,0 +1,106 @@
+<#
+.SYNOPSIS
+    This is a gradle wrapper script to help run the Logstash unit tests on Windows.
+
+.PARAMETER UnnamedArgument1
+    Optionally allows to specify a subset of tests.
+    Allows values are "ruby" or "java".
+    If unset, all tests are executed.
+
+.EXAMPLE
+    .\ci\unit_tests.ps1
+    Runs all unit tests.
+
+    .\ci\unit_tests.ps1 java
+    Runs only Java unit tests.
+#>
+
+$selectedTestSuite="all"
+
+if ($args.Count -eq 1) {
+    $selectedTestSuite=$args[0]
+}
+
+$startingPath = Get-Location
+
+## Map a drive letter to the current path to avoid path length issues
+
+# First, check if there is already a mapping
+$currentDir = $PWD.Path
+$substOutput = subst
+
+# Filter the subst output based on the path
+$matchedLines = $substOutput | Where-Object { $_ -like "*$currentDir*" }
+
+if ($matchedLines) {
+    # $currentDir seems to be already mapped to another drive letter; switch to this drive
+    # Extract the drive letter from the matched lines
+    $driveLetter = $matchedLines | ForEach-Object {
+        # Split the line by colon and extract the drive letter
+        ($_ -split ':')[0]
+    }
+    $drivePath = "$driveLetter`:"
+
+    Write-Output "$currentDir is already mapped to $drivePath."
+    Set-Location -Path $drivePath
+    Write-Output "Changing drive to $drivePath."
+}
+else {
+    # $currentDir isn't mapped to a drive letter, let's find a free drive letter and change to it
+
+    # Loop through drive letters A to Z; we don't use the 'A'..'Z' for BWC with Windows 2016 / Powershell < 7
+    for ($driveLetterAscii = 65; $driveLetterAscii -le 90; $driveLetterAscii++) {
+        $drivePath = [char]$driveLetterAscii + ":"
+
+        # check if the drive letter is available
+        if (-not (Test-Path $drivePath)) {
+            # found a free drive letter, create the virtual drive mapping and switch to it
+            subst $drivePath $currentDir
+
+            Write-Output "Mapped $currentDir to $drivePath"
+            Set-Location -Path $drivePath
+            Write-Output "Changing drive to $drivePath."
+            # exit the loop since we found a free drive letter
+            break
+        }
+    }
+}
+
+if (Test-Path Env:BUILD_JAVA_HOME) {    
+    if (Test-Path Env:GRADLE_OPTS) {    
+        $env:GRADLE_OPTS=$env:GRADLE_OPTS + " " + "-Dorg.gradle.java.home=" + $env:BUILD_JAVA_HOME
+    } else {
+        $env:GRADLE_OPTS="-Dorg.gradle.java.home=" + $env:BUILD_JAVA_HOME
+    }
+}
+
+$testOpts = "GRADLE_OPTS: $env:GRADLE_OPTS, BUILD_JAVA_HOME: $env:BUILD_JAVA_HOME"
+
+try {
+    if ($selectedTestSuite -eq "java") {
+        Write-Host "~~~ :java: Running Java tests via Gradle using $testOpts"
+        $CIScript = ".\gradlew.bat javaTests --console=plain --no-daemon --info"
+        Invoke-Expression $CIScript
+    }
+    elseif ($selectedTestSuite -eq "ruby") {
+        Write-Host "~~~ :ruby: Running Ruby tests via Gradle using $testOpts"
+        $CIScript = ".\gradlew.bat rubyTests --console=plain --no-daemon --info"
+        Invoke-Expression $CIScript
+    }
+    else {
+        Write-Host "~~~ Running all tests via Gradle using $testOpts"
+        $CIScript = ".\gradlew.bat test --console=plain --no-daemon --info"
+        Invoke-Expression $CIScript
+    }
+
+    if ($LASTEXITCODE -ne 0) {
+        throw "Test script $CIScript failed with a non-zero code: $LASTEXITCODE"
+    }
+} catch {
+    # tests failed
+    Write-Host "^^^ +++"
+    exit 1
+}
+
+# switch back to the path when the script started
+Set-Location -Path $startingPath