[python] PY-79930 don't fold __future__ imports

Merge-request: IJ-MR-171486
Merged-by: Morgan Bartholomew <morgan.bartholomew@jetbrains.com>

GitOrigin-RevId: 968e8d7c03dd7e46ff55316cffd07e7e2a9c7b54

python/python-syntax/src/com/jetbrains/python/PythonFoldingBuilder.kt

@@ -110,9 +110,10 @@ open class PythonFoldingBuilder : CustomFoldingBuilder(), DumbAware {
     val elementType = node.elementType
     if (node.psi is PyAstFile) {
       val imports = (node.psi as PyAstFile).importBlock
-      if (imports.size > 1) {
-        val firstImport: PyAstImportStatementBase = imports[0]
-        val lastImport: PyAstImportStatementBase = imports[imports.size - 1]
+      val firstIndex = imports.takeWhile { (it as? PyAstFromImportStatement)?.isFromFuture == true }.size
+      if (imports.size - firstIndex > 1) {
+        val firstImport: PyAstImportStatementBase = imports[firstIndex]
+        val lastImport: PyAstImportStatementBase = imports.last()
         descriptors.add(FoldingDescriptor(firstImport, TextRange(firstImport.textRange.startOffset,
                                                                  lastImport.textRange.endOffset)))
       }

python/testData/folding/futureImport.py

@@ -0,0 +1,9 @@
+"""This is a module-level docstring."""
+
+from __future__ import annotations
+from __future__ import another_one
+
+<fold text='import ...'>import os
+import sys</fold>
+
+print(os, sys)

python/testData/folding/futureImportWithOneImport.py

@@ -0,0 +1,7 @@
+"""This is a module-level docstring."""
+
+from __future__ import annotations
+
+import os
+
+print(os.path)

python/testSrc/com/jetbrains/python/PyFoldingTest.java

@@ -245,4 +245,14 @@ public class PyFoldingTest extends PyTestCase {
   public void testMatchFolding() {
     doTest();
   }
+  
+  // PY-79930
+  public void testFutureImport() {
+    doTest();
+  }
+
+  // PY-79930
+  public void testFutureImportWithOneImport() {
+    doTest();
+  }
 }