PY-78033/Sort-Base-interpreter-list

After this refactoring we how have `comparators.kt` with sorting logic that is used both by `SystemPython` and `PythonSelectableInterpreter` (ViewModel thing for V2).

Tests are also added.

GitOrigin-RevId: 9d04405829f31874d15cb893d9261c7997cb2dd5

python/ide/impl/BUILD.bazel

@@ -97,6 +97,7 @@ jvm_library(
     "//python/services/system-python:system-python_test_lib",
     "//platform/eel",
     "//python/services/shared",
+    "//python/services/shared:shared_test_lib",
     "//python/poetry",
     "//python/python-venv:community-impl-venv",
     "//python/python-venv:community-impl-venv_test_lib",

python/services/internal-impl/BUILD.bazel

@@ -35,6 +35,7 @@ jvm_library(
     "@lib//:kotlin-stdlib",
     "//python/python-parser:parser",
     "//python/services/shared",
+    "//python/services/shared:shared_test_lib",
     "//platform/eel-provider",
     "@lib//:jetbrains-annotations",
     "//python/openapi:community",

python/services/internal-impl/src/com/intellij/python/community/services/internal/impl/VanillaPythonWithLanguageLevelImpl.kt

@@ -7,6 +7,8 @@ import com.intellij.platform.eel.provider.getEelDescriptor
 import com.intellij.python.community.execService.python.validatePythonAndGetVersion
 import com.intellij.python.community.services.internal.impl.VanillaPythonWithLanguageLevelImpl.Companion.concurrentLimit
 import com.intellij.python.community.services.internal.impl.VanillaPythonWithLanguageLevelImpl.Companion.createByPythonBinary
+import com.intellij.python.community.services.shared.LanguageLevelComparator
+import com.intellij.python.community.services.shared.PythonWithLanguageLevel
 import com.intellij.python.community.services.shared.VanillaPythonWithLanguageLevel
 import com.jetbrains.python.PythonBinary
 import com.jetbrains.python.Result
@@ -26,7 +28,7 @@ import kotlin.io.path.relativeTo
 class VanillaPythonWithLanguageLevelImpl internal constructor(
   override val pythonBinary: PythonBinary,
   override val languageLevel: LanguageLevel,
-) : VanillaPythonWithLanguageLevel {
+) : VanillaPythonWithLanguageLevel, Comparable<PythonWithLanguageLevel> {
 
   companion object {
 
@@ -82,4 +84,5 @@ class VanillaPythonWithLanguageLevelImpl internal constructor(
     return "$pythonString ($languageLevel)"
   }
 
+  override fun compareTo(other: PythonWithLanguageLevel): Int = LanguageLevelComparator.compare(this, other)
 }

python/services/shared/BUILD.bazel

@@ -1,5 +1,5 @@
 ### auto-generated section `build intellij.python.community.services.shared` start
-load("@rules_jvm//:jvm.bzl", "jvm_library", "jvm_resources")
+load("@rules_jvm//:jvm.bzl", "jvm_library", "jvm_resources", "jvm_test")
 
 jvm_resources(
   name = "shared_resources",
@@ -21,4 +21,31 @@ jvm_library(
   ],
   runtime_deps = [":shared_resources"]
 )
+
+jvm_library(
+  name = "shared_test_lib",
+  visibility = ["//visibility:public"],
+  srcs = glob(["tests/**/*.kt", "tests/**/*.java"], allow_empty = True),
+  associates = [":shared"],
+  deps = [
+    "@lib//:kotlin-stdlib",
+    "//python/openapi:community",
+    "//python/openapi:community_test_lib",
+    "@lib//:jetbrains-annotations",
+    "//platform/eel-provider",
+    "@lib//:junit5",
+    "@lib//:kotlinx-coroutines-core",
+    "//platform/testFramework/junit5",
+    "//platform/testFramework/junit5:junit5_test_lib",
+    "@lib//:hamcrest",
+    "//python/python-exec-service/execService.python",
+    "//python/python-exec-service/execService.python:execService.python_test_lib",
+  ],
+  runtime_deps = [":shared_resources"]
+)
+
+jvm_test(
+  name = "shared_test",
+  runtime_deps = [":shared_test_lib"]
+)
 ### auto-generated section `build intellij.python.community.services.shared` end

python/services/shared/intellij.python.community.services.shared.iml

@@ -5,6 +5,7 @@
     <content url="file://$MODULE_DIR$">
       <sourceFolder url="file://$MODULE_DIR$/resources" type="java-resource" />
       <sourceFolder url="file://$MODULE_DIR$/src" isTestSource="false" />
+      <sourceFolder url="file://$MODULE_DIR$/tests" isTestSource="true" />
     </content>
     <orderEntry type="inheritedJdk" />
     <orderEntry type="sourceFolder" forTests="false" />

python/services/shared/src/com/intellij/python/community/services/shared/LanguageLevelHolder.kt

@@ -0,0 +1,11 @@
+// Copyright 2000-2025 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
+package com.intellij.python.community.services.shared
+
+import com.jetbrains.python.psi.LanguageLevel
+
+/**
+ * Something with language level
+ */
+interface LanguageLevelHolder {
+  val languageLevel: LanguageLevel
+}

python/services/shared/src/com/intellij/python/community/services/shared/PythonWithLanguageLevel.kt

@@ -2,21 +2,15 @@
 package com.intellij.python.community.services.shared
 
 import com.intellij.python.community.execService.python.advancedApi.ExecutablePython
-import com.jetbrains.python.psi.LanguageLevel
 
 /**
  * Python (vanilla, conda, whatever) with known language level.
  */
-interface PythonWithLanguageLevel : Comparable<PythonWithLanguageLevel>, PythonWithName {
-  val languageLevel: LanguageLevel
+interface PythonWithLanguageLevel : PythonWithName, LanguageLevelHolder {
 
   /**
    * Convert python to something that can be executed on [java.util.concurrent.ExecutorService]
    */
   val asExecutablePython: ExecutablePython
 
-
-  // Backward: first python is the highest
-  override fun compareTo(other: PythonWithLanguageLevel): Int = languageLevel.compareTo(other.languageLevel) * -1
-
 }

python/services/shared/src/com/intellij/python/community/services/shared/PythonWithUi.kt

@@ -1,6 +1,7 @@
 // Copyright 2000-2025 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
 package com.intellij.python.community.services.shared
 
-interface PythonWithUi : PythonWithLanguageLevel {
-  val ui: UICustomization?
-}
+/**
+ * Python that has both [languageLevel] and [ui]
+ */
+interface PythonWithUi : PythonWithLanguageLevel, UiHolder

python/services/shared/src/com/intellij/python/community/services/shared/UiCustomization.kt

@@ -10,4 +10,6 @@ data class UICustomization(
    */
   val title: @Nls String,
   val icon: Icon? = null,
-)
+) : Comparable<UICustomization> {
+  override fun compareTo(other: UICustomization): Int = title.compareTo(other.title)
+}

python/services/shared/src/com/intellij/python/community/services/shared/UiHolder.kt

@@ -0,0 +1,9 @@
+// Copyright 2000-2025 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
+package com.intellij.python.community.services.shared
+
+interface UiHolder {
+  /**
+   * UI hints on how to display this python to the end user: icon, title, etc
+   */
+  val ui: UICustomization?
+}

python/services/shared/src/com/intellij/python/community/services/shared/comparators.kt

@@ -0,0 +1,21 @@
+// Copyright 2000-2025 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
+package com.intellij.python.community.services.shared
+
+import java.util.*
+
+
+object LanguageLevelComparator : Comparator<LanguageLevelHolder> {
+  override fun compare(o1: LanguageLevelHolder, o2: LanguageLevelHolder): Int =
+    // Backward: first python is the highest
+    o1.languageLevel.compareTo(o2.languageLevel) * -1
+}
+
+object UiComparator : Comparator<UiHolder> {
+  override fun compare(o1: UiHolder, o2: UiHolder): Int =
+    Objects.compare(o1.ui, o2.ui, Comparator.nullsFirst(UICustomization::compareTo))
+}
+
+class LanguageLevelWithUiComparator<T> : Comparator<T> where T : LanguageLevelHolder, T : UiHolder {
+  override fun compare(o1: T, o2: T): Int =
+    LanguageLevelComparator.compare(o1, o2) * 10 + UiComparator.compare(o1, o2)
+}

python/services/shared/src/com/intellij/python/community/services/shared/package-info.java

@@ -0,0 +1,8 @@
+// Copyright 2000-2025 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
+/**
+ * Various details for pythons, not intended to be used directly (except for comparators).
+ */
+@ApiStatus.Internal
+package com.intellij.python.community.services.shared;
+
+import org.jetbrains.annotations.ApiStatus;

python/services/shared/tests/com/intellij/python/junit5Tests/unit/comparators/ComparatorsTest.kt

@@ -0,0 +1,44 @@
+// Copyright 2000-2025 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
+package com.intellij.python.junit5Tests.unit.comparators
+
+import com.intellij.python.community.services.shared.LanguageLevelHolder
+import com.intellij.python.community.services.shared.LanguageLevelWithUiComparator
+import com.intellij.python.community.services.shared.UICustomization
+import com.intellij.python.community.services.shared.UiHolder
+import com.jetbrains.python.psi.LanguageLevel
+import org.hamcrest.MatcherAssert
+import org.hamcrest.Matchers
+import org.junit.jupiter.api.Test
+import java.util.*
+
+class ComparatorsTest {
+
+  @Test
+  fun testComparators() {
+    val mocks = arrayOf(
+      MockLevel(LanguageLevel.PYTHON314),
+      MockLevel(LanguageLevel.PYTHON310),
+      MockLevel(LanguageLevel.PYTHON310, ui = UICustomization("A")),
+      MockLevel(LanguageLevel.PYTHON310, ui = UICustomization("Z")),
+      MockLevel(LanguageLevel.PYTHON310, ui = UICustomization("B")),
+      MockLevel(LanguageLevel.PYTHON27),
+      MockLevel(LanguageLevel.PYTHON313),
+    )
+    val set = TreeSet(LanguageLevelWithUiComparator<MockLevel>())
+    set.addAll(mocks)
+    MatcherAssert.assertThat("", set, Matchers.contains(
+      MockLevel(LanguageLevel.PYTHON314),
+      MockLevel(LanguageLevel.PYTHON313),
+      MockLevel(LanguageLevel.PYTHON310),
+      MockLevel(LanguageLevel.PYTHON310, ui = UICustomization("A")),
+      MockLevel(LanguageLevel.PYTHON310, ui = UICustomization("B")),
+      MockLevel(LanguageLevel.PYTHON310, ui = UICustomization("Z")),
+      MockLevel(LanguageLevel.PYTHON27)
+    ))
+  }
+}
+
+private data class MockLevel(
+  override val languageLevel: LanguageLevel,
+  override val ui: UICustomization? = null,
+) : LanguageLevelHolder, UiHolder

python/services/system-python/BUILD.bazel

@@ -61,6 +61,7 @@ jvm_library(
     "//python/testFramework",
     "@lib//:hamcrest",
     "//python/services/shared",
+    "//python/services/shared:shared_test_lib",
     "//python/services/internal-impl:python-community-services-internal-impl",
     "//python/services/internal-impl:python-community-services-internal-impl_test_lib",
     "//platform/util",

python/services/system-python/src/com/intellij/python/community/services/systemPython/api.kt

@@ -6,6 +6,7 @@ import com.intellij.openapi.components.service
 import com.intellij.platform.eel.EelApi
 import com.intellij.platform.eel.provider.localEel
 import com.intellij.python.community.impl.venv.createVenv
+import com.intellij.python.community.services.shared.LanguageLevelWithUiComparator
 import com.intellij.python.community.services.shared.PythonWithUi
 import com.intellij.python.community.services.shared.UICustomization
 import com.intellij.python.community.services.shared.VanillaPythonWithLanguageLevel
@@ -55,7 +56,11 @@ fun SystemPythonService(): SystemPythonService = ApplicationManager.getApplicati
  *
  * Instances could be obtained with [SystemPythonService]
  */
-class SystemPython internal constructor(private val impl: VanillaPythonWithLanguageLevel, override val ui: UICustomization?) : VanillaPythonWithLanguageLevel by impl, PythonWithUi {
+class SystemPython internal constructor(private val delegate: VanillaPythonWithLanguageLevel, override val ui: UICustomization?) : VanillaPythonWithLanguageLevel by delegate, PythonWithUi, Comparable<SystemPython> {
+
+  private companion object {
+    val comparator = LanguageLevelWithUiComparator<SystemPython>()
+  }
 
   override fun equals(other: Any?): Boolean {
     if (this === other) return true
@@ -63,21 +68,23 @@ class SystemPython internal constructor(private val impl: VanillaPythonWithLangu
 
     other as SystemPython
 
-    if (impl != other.impl) return false
+    if (delegate != other.delegate) return false
     if (ui != other.ui) return false
 
     return true
   }
 
   override fun hashCode(): Int {
-    var result = impl.hashCode()
+    var result = delegate.hashCode()
     result = 31 * result + (ui?.hashCode() ?: 0)
     return result
   }
 
   override fun toString(): String {
-    return "SystemPython(impl=$impl, ui=$ui)"
+    return "SystemPython(delegate=$delegate, ui=$ui)"
   }
+
+  override fun compareTo(other: SystemPython): Int = comparator.compare(this, other)
 }
 
 /**

python/services/system-python/src/com/intellij/python/community/services/systemPython/systemPythonServiceImpl.kt

@@ -84,7 +84,7 @@ internal class SystemPythonServiceImpl(scope: CoroutineScope) : SystemPythonServ
       else {
         cache.get(eelApi.descriptor)
       }.sorted()
-    } ?: searchPythonsPhysicallyNoCache(eelApi)
+    } ?: searchPythonsPhysicallyNoCache(eelApi).sorted()
 
 
   class MyServiceState : BaseState() {

python/src/com/jetbrains/python/sdk/add/v2/models.kt

@@ -15,8 +15,7 @@ import com.intellij.openapi.projectRoots.Sdk
 import com.intellij.openapi.util.io.NioFiles
 import com.intellij.openapi.vfs.toNioPathOrNull
 import com.intellij.python.community.services.internal.impl.VanillaPythonWithLanguageLevelImpl
-import com.intellij.python.community.services.shared.UICustomization
-import com.intellij.python.community.services.shared.VanillaPythonWithLanguageLevel
+import com.intellij.python.community.services.shared.*
 import com.intellij.python.community.services.systemPython.SystemPython
 import com.intellij.python.community.services.systemPython.SystemPythonService
 import com.intellij.python.hatch.HatchConfiguration
@@ -48,7 +47,8 @@ import com.jetbrains.python.sdk.uv.impl.getUvExecutable
 import com.jetbrains.python.venvReader.tryResolvePath
 import kotlinx.coroutines.*
 import kotlinx.coroutines.flow.*
-import org.apache.commons.lang3.builder.CompareToBuilder
+import org.jetbrains.annotations.ApiStatus
+import org.jetbrains.annotations.TestOnly
 import java.nio.file.InvalidPathException
 import java.nio.file.Path
 import kotlin.io.path.Path
@@ -83,6 +83,12 @@ abstract class PythonAddInterpreterModel(
   val interpreterLoading: MutableStateFlow<Boolean> = MutableStateFlow(true)
   val condaEnvironmentsLoading: MutableStateFlow<Boolean> = MutableStateFlow(true)
 
+  @TestOnly
+  @ApiStatus.Internal
+  fun addDetected(detected: DetectedSelectableInterpreter) {
+    _detectedInterpreters.value += detected
+  }
+
   // If the project is provided, sdks associated with it will be kept in the list of interpreters. If not, then they will be filtered out.
   open fun initialize(scope: CoroutineScope) {
     merge(
@@ -111,7 +117,7 @@ abstract class PythonAddInterpreterModel(
       manuallyAddedInterpreters,
     ) { known, detected, added ->
       added + known + detected
-    }.stateIn(scope, started = SharingStarted.Eagerly, initialValue = emptyList())
+    }.map { it.sorted() }.stateIn(scope, started = SharingStarted.Eagerly, initialValue = emptyList())
 
     this.baseInterpreters = allInterpreters.map { all ->
       all.filter { it.isBasePython() }
@@ -365,7 +371,11 @@ class PythonLocalAddInterpreterModel(projectPathFlows: ProjectPathFlows) : Pytho
 }
 
 
-sealed class PythonSelectableInterpreter : Comparable<PythonSelectableInterpreter> {
+sealed class PythonSelectableInterpreter : Comparable<PythonSelectableInterpreter>, UiHolder, LanguageLevelHolder {
+  companion object {
+    private val comparator = LanguageLevelWithUiComparator<PythonSelectableInterpreter>()
+  }
+
   /**
    * Base python is some system python (not venv) which can be used as a base for venv.
    * In terms of flavors we call it __not__ [PythonSdkFlavor.isPlatformIndependent]
@@ -375,15 +385,12 @@ sealed class PythonSelectableInterpreter : Comparable<PythonSelectableInterprete
   }
 
   abstract val homePath: String
-  abstract val languageLevel: LanguageLevel
-  open val uiCustomization: UICustomization? = null
+  abstract override val languageLevel: LanguageLevel
+  override val ui: UICustomization? = null
   override fun toString(): String = "PythonSelectableInterpreter(homePath='$homePath')"
 
   override fun compareTo(other: PythonSelectableInterpreter): Int =
-    CompareToBuilder()
-      .append(uiCustomization?.hashCode(), other.uiCustomization?.hashCode())
-      .append(other.languageLevel, languageLevel)
-      .toComparison()
+    comparator.compare(this, other)
 }
 
 class ExistingSelectableInterpreter(
@@ -411,11 +418,11 @@ class DetectedSelectableInterpreter(
   override val homePath: String,
   override val languageLevel: LanguageLevel,
   private val isBase: Boolean,
-  override val uiCustomization: UICustomization? = null,
+  override val ui: UICustomization? = null,
 ) : PythonSelectableInterpreter() {
   override suspend fun isBasePython(): Boolean = isBase
   override fun toString(): String {
-    return "DetectedSelectableInterpreter(homePath='$homePath', languageLevel=$languageLevel, isBase=$isBase, uiCustomization=$uiCustomization)"
+    return "DetectedSelectableInterpreter(homePath='$homePath', languageLevel=$languageLevel, isBase=$isBase, uiCustomization=$ui)"
   }
 
 }
@@ -436,7 +443,7 @@ class ManuallyAddedSelectableInterpreter(
 class InstallableSelectableInterpreter(val sdk: PySdkToInstall) : PythonSelectableInterpreter() {
   override suspend fun isBasePython(): Boolean = true
   override val homePath: String = ""
-  override val languageLevel = PySdkUtil.getLanguageLevelForSdk(sdk)
+  override val languageLevel: LanguageLevel = PySdkUtil.getLanguageLevelForSdk(sdk)
 }
 
 

python/src/com/jetbrains/python/sdk/add/v2/uiUtils.kt

@@ -159,8 +159,8 @@ internal fun SimpleColoredComponent.customizeForPythonInterpreter(isLoading: Boo
 
   when (interpreter) {
     is DetectedSelectableInterpreter, is ManuallyAddedSelectableInterpreter -> {
-      icon = IconLoader.getTransparentIcon(interpreter.uiCustomization?.icon ?: PythonPsiApiIcons.Python)
-      val title = interpreter.uiCustomization?.title ?: message("sdk.rendering.detected.grey.text")
+      icon = IconLoader.getTransparentIcon(interpreter.ui?.icon ?: PythonPsiApiIcons.Python)
+      val title = interpreter.ui?.title ?: message("sdk.rendering.detected.grey.text")
       append(String.format("Python %-4s", interpreter.languageLevel))
       append(" (" + replaceHomePathToTilde(interpreter.homePath) + ") $title", SimpleTextAttributes.GRAYED_SMALL_ATTRIBUTES)
     }