Support pyenv on Windows

Jenkinsfile

@@ -38,14 +38,11 @@ eventRecorder.timedStage('Integration Test') {
         String venvVersion = venv.run(returnStdout: true, script: 'python --version')
         assert venvVersion.startsWith('Python 3')
 
-        if (isUnix()) {
-          echo 'Test VirtualEnv.createWithPyenv'
-          Object pyvenv = pyenv.createVirtualEnv('3.10.3')
-          String pyvenvVersion =
-            pyvenv.run(returnStdout: true, script: 'python --version')
-          echo pyvenvVersion
-          assert pyvenvVersion.trim() == 'Python 3.10.3'
-        }
+        echo 'Test VirtualEnv.createWithPyenv'
+        Object pyvenv = pyenv.createVirtualEnv('3.10.3')
+        String pyvenvVersion = pyvenv.run(returnStdout: true, script: 'python --version')
+        echo pyvenvVersion
+        assert pyvenvVersion.trim() == 'Python 3.10.3'
       }
     }
   }

VERSION

@@ -1 +1 @@
-0.14.4
+0.15.0

src/com/ableton/Pyenv.groovy

@@ -23,7 +23,8 @@ class Pyenv implements Serializable {
 
   Pyenv(Object script, String pyenvRoot) {
     this.script = script
-    this.pyenvRoot = pyenvRoot
+    this.pyenvRoot = script.env.OS == 'Windows_NT' ?
+      pyenvRoot.replace('\\', '/') : pyenvRoot
   }
 
   /**
@@ -44,10 +45,6 @@ class Pyenv implements Serializable {
 
     String trimmedPythonVersion = pythonVersion.trim()
 
-    if (script.env.OS == 'Windows_NT') {
-      script.error 'This method is not supported on Windows'
-    }
-
     if (!versionSupported(trimmedPythonVersion)) {
       script.withEnv(["PYENV_ROOT=${pyenvRoot}"]) {
         String pyenvVersion = script.sh(
@@ -62,20 +59,31 @@ class Pyenv implements Serializable {
 
     VirtualEnv venv = new VirtualEnv(script, randomSeed)
     script.retry(INSTALLATION_RETRIES) {
-      List installCommands = [
-        "export PYENV_ROOT=${pyenvRoot}",
-        "export PATH=\$PYENV_ROOT/bin:\$PATH",
-        'eval "\$(pyenv init --path)"',
-        'eval "\$(pyenv init -)"',
-        "pyenv install --skip-existing ${trimmedPythonVersion}",
-        "pyenv shell ${trimmedPythonVersion}",
-        'pip install virtualenv',
-        "virtualenv ${venv.venvRootDir}",
-      ]
-      venv.script.sh(
-        label: "Install Python version ${trimmedPythonVersion} with pyenv",
-        script: installCommands.join('\n') + '\n',
-      )
+      script.withEnv(["PYENV_VERSION=${trimmedPythonVersion}"]) {
+        List installCommands = ["export PYENV_ROOT=${pyenvRoot}"]
+        if (script.env.OS != 'Windows_NT') {
+          installCommands += [
+            "export PATH=\$PYENV_ROOT/bin:\$PATH",
+            'eval "\$(pyenv init --path)"',
+            'eval "\$(pyenv init -)"',
+          ]
+        } else {
+          String posixPyenvRoot = pyenvRoot[1] == ':' ?
+            "/${pyenvRoot[0].toLowerCase()}/${pyenvRoot.substring(3)}" : pyenvRoot
+          installCommands.add(
+            "export PATH=${posixPyenvRoot}/shims:${posixPyenvRoot}/bin:\$PATH"
+          )
+        }
+        installCommands += [
+          "pyenv install --skip-existing ${trimmedPythonVersion}",
+          'pyenv exec pip install virtualenv',
+          "pyenv exec virtualenv ${venv.venvRootDir}",
+        ]
+        venv.script.sh(
+          label: "Install Python version ${trimmedPythonVersion} with pyenv",
+          script: installCommands.join('\n') + '\n',
+        )
+      }
     }
 
     return venv
@@ -93,10 +101,6 @@ class Pyenv implements Serializable {
     assertPyenvRoot()
     boolean result = false
 
-    if (script.env.OS == 'Windows_NT') {
-      script.error 'This method is not supported on Windows'
-    }
-
     script.withEnv(["PYENV_ROOT=${pyenvRoot}"]) {
       String allVersions = script.sh(
         label: 'Get Python versions supported by Pyenv',

test/com/ableton/PyenvTest.groovy

@@ -101,9 +101,26 @@ class PyenvTest extends BasePipelineTest {
 
   @Test
   void createVirtualEnvWindows() {
+    String pythonVersion = '1.2.3'
+    String pyenvRoot = 'C:\\mock\\pyenv\\root'
+    String posixPyenvRoot = '/c/mock/pyenv/root'
+    String shPyenvRoot = 'C:/mock/pyenv/root'
+    List shMocks = [
+      new Tuple(installCommands(
+        shPyenvRoot, pythonVersion, false, posixPyenvRoot), '', 0
+      ),
+      new Tuple("${shPyenvRoot}/bin/pyenv install --list", '''Available versions:
+  1.2.3
+''', 0),
+    ]
+    shMocks.each { mock -> helper.addShMock(mock[0], mock[1], mock[2]) }
+    helper.registerAllowedMethod('fileExists', [String]) { return true }
     script.env['OS'] = 'Windows_NT'
 
-    assertThrows(Exception) { new Pyenv(script, 'C:\\pyenv').createVirtualEnv('1.2.3') }
+    Object venv = new Pyenv(script, pyenvRoot).createVirtualEnv(pythonVersion, 1)
+
+    assertEquals("/workspace/.venv/${TEST_RANDOM_NAME}" as String, venv.venvRootDir)
+    shMocks.each { mock -> assertCallStackContains(mock[0]) }
   }
 
   @Test
@@ -135,25 +152,51 @@ class PyenvTest extends BasePipelineTest {
 
     assertTrue(new Pyenv(script, pyenvRoot).versionSupported('2.1.3'))
     assertFalse(new Pyenv(script, pyenvRoot).versionSupported('2.1.3333'))
+    assertCallStackContains("${pyenvRoot}/bin/pyenv install --list")
   }
 
   @Test
   void versionSupportedWindows() {
+    // Resembles pyenv's output, at least as of version 2.3.x
+    String mockPyenvVersions = '''Available versions:
+  2.1.3
+  2.2.3
+  2.3.7
+'''
+    String shPyenvRoot = 'C:/pyenv'
+    helper.addShMock("${shPyenvRoot}/bin/pyenv install --list", mockPyenvVersions, 0)
+    helper.registerAllowedMethod('fileExists', [String]) { return true }
     script.env['OS'] = 'Windows_NT'
 
-    assertThrows(Exception) { new Pyenv(script, 'C:\\pyenv').versionSupported('1.2.3') }
+    assertTrue(new Pyenv(script, shPyenvRoot).versionSupported('2.1.3'))
+    assertFalse(new Pyenv(script, shPyenvRoot).versionSupported('2.1.3333'))
+    assertCallStackContains("${shPyenvRoot}/bin/pyenv install --list")
   }
 
-  private String installCommands(String pyenvRoot, String pythonVersion) {
+  private String installCommands(
+    String pyenvRoot,
+    String pythonVersion,
+    boolean isUnix = true,
+    String posixPyenvRoot = null
+  ) {
     List installCommands = [
       "export PYENV_ROOT=${pyenvRoot}",
-      "export PATH=\$PYENV_ROOT/bin:\$PATH",
-      'eval "\$(pyenv init --path)"',
-      'eval "\$(pyenv init -)"',
+    ]
+    if (isUnix) {
+      installCommands += [
+        "export PATH=\$PYENV_ROOT/bin:\$PATH",
+        'eval "\$(pyenv init --path)"',
+        'eval "\$(pyenv init -)"',
+      ]
+    } else {
+      installCommands += [
+        "export PATH=${posixPyenvRoot}/shims:${posixPyenvRoot}/bin:\$PATH",
+      ]
+    }
+    installCommands += [
       "pyenv install --skip-existing ${pythonVersion}",
-      "pyenv shell ${pythonVersion}",
-      'pip install virtualenv',
-      "virtualenv /workspace/.venv/${TEST_RANDOM_NAME}",
+      'pyenv exec pip install virtualenv',
+      "pyenv exec virtualenv /workspace/.venv/${TEST_RANDOM_NAME}",
     ]
 
     return installCommands.join('\n') + '\n'