PY-82426 conda: environment.yaml: Fix add dependencies in edge cases

Signed-off-by: Nikita.Ashihmin <nikita.ashihmin@jetbrains.com>

GitOrigin-RevId: d2cfa776a63ab9bd629e31fd8a87a65fe7506ecd

python/src/com/jetbrains/python/inspections/requirement/PyRequirementVisitor.kt

@@ -56,6 +56,8 @@ class PyRequirementVisitor(
     val sdk = module.pythonSdk ?: return
     val manager = PythonPackageManager.forSdk(module.project, sdk)
     val requirementsManager = manager.getDependencyManager() ?: return
+    if (requirementsManager.getDependenciesFile() == null)
+      return
     val installedNotDeclaredChecker = InstalledButNotDeclaredChecker(ignoredPackages, manager)
     val packageName = installedNotDeclaredChecker.getUndeclaredPackageName(importedPyModule = importedPyModule) ?: return
 

python/src/com/jetbrains/python/packaging/conda/environmentYml/format/EnvironmentYmlModifier.kt

@@ -45,6 +45,10 @@ object EnvironmentYmlModifier {
     val dependenciesText = "dependencies:"
     val dependenciesIndex = text.indexOf(dependenciesText)
 
+    if (dependenciesIndex < 0) {
+      modifiedContent.append("\ndependencies:\n  - $packageName")
+    }
+
     if (dependenciesIndex >= 0) {
       // Find the indentation level by looking at existing entries
       val indentPattern = INDENT_PATTERN

python/testData/requirement/environmentYmlEmpty/environment.yml

@@ -0,0 +1,21 @@
+# environment.yml - Comprehensive test file for dependency parsing
+name: test-environment
+
+channels:
+  - defaults
+  - conda-forge
+  - bioconda
+  - pytorch
+  - nvidia
+  - anaconda
+  - https://conda.anaconda.org/pyviz
+
+# Environment variables
+variables:
+  CUDA_HOME: /usr/local/cuda
+  PYTHONPATH: /custom/python/path
+  API_KEY: your-api-key-here
+  DEBUG: "1"
+
+# Prefix for installation (optional)
+prefix: /path/to/conda/envs/test-environment

python/testData/requirement/environmentYmlEmpty/requirements.txt

@@ -0,0 +1 @@
+tqdm==1.2.3

python/testSrc/com/jetbrains/python/packaging/conda/EnvironmentYmlHelperTest.kt

@@ -4,6 +4,7 @@ package com.jetbrains.python.packaging.conda
 import com.intellij.openapi.util.io.FileUtil
 import com.intellij.openapi.vfs.VirtualFileManager
 import com.jetbrains.python.fixtures.PyTestCase
+import com.jetbrains.python.packaging.PyRequirement
 import com.jetbrains.python.packaging.PyRequirementParser
 import com.jetbrains.python.packaging.conda.environmentYml.format.CondaEnvironmentYmlParser
 import com.jetbrains.python.packaging.conda.environmentYml.format.EnvironmentYmlModifier
@@ -11,6 +12,33 @@ import org.junit.jupiter.api.Assertions
 import java.io.File
 
 class EnvironmentYmlHelperTest : PyTestCase() {
+  fun testAddRequirementEmpty() {
+    val virtualFile = getVirtualFileByName("$testDataPath/requirement/environmentYmlEmpty/environment.yml")!!
+
+    // Create a temporary copy of the file
+    val tempDir = FileUtil.createTempDirectory(getTestName(false), null)
+    val tempFile = File(tempDir.path, "environment.yml")
+    virtualFile.inputStream.use { input ->
+      tempFile.outputStream().use { output ->
+        input.copyTo(output)
+      }
+    }
+    val tempVirtualFile = VirtualFileManager.getInstance().refreshAndFindFileByUrl("file://${tempFile.absolutePath}")!!
+
+    // Parse the updated file and check if the package was added
+    val requirements = CondaEnvironmentYmlParser.fromFile(tempVirtualFile)!!
+    Assertions.assertEquals(emptyList<PyRequirement>(), requirements)
+
+    // Add a new package that doesn't exist in the file
+    val newPackageName = "new-test-package"
+    EnvironmentYmlModifier.addRequirement(myFixture.project, tempVirtualFile, newPackageName)
+    val newPackageRequirement = PyRequirementParser.fromLine(newPackageName)!!
+
+    // Parse the file again and check that the package appears only once
+    val updatedRequirements = CondaEnvironmentYmlParser.fromFile(tempVirtualFile)!!
+    Assertions.assertEquals(listOf(newPackageRequirement), updatedRequirements)
+  }
+
   fun testAddRequirement() {
     val virtualFile = getVirtualFileByName("$testDataPath/requirement/environmentYml/environment.yml")!!