PY-61856 PEP 695 Type Parameter Syntax: Code compatibility inspection and unsupported features annotator

GitOrigin-RevId: 164a07daff1059ac1a421e1a883168924f82559e

python/python-psi-impl/resources/messages/PyPsiBundle.properties

@@ -791,6 +791,7 @@ INSP.compatibility.check.for.compatibility.with.python.versions=Check for compat
 INSP.compatibility.inspection.unsupported.feature.prefix=Python {0,choice,1#version|2#versions} {1} {0,choice,1#does|2#do} not {2}
 INSP.compatibility.feature.support.variable.annotations=support variable annotations
 INSP.compatibility.feature.support.this.syntax=support this syntax
+INSP.compatibility.feature.support.type.alias.statements=support type alias statements
 INSP.compatibility.feature.have.module.builtins=have module builtins
 INSP.compatibility.feature.have.module.builtin=have module __builtin__
 INSP.compatibility.feature.support.starred.expressions.as.assignment.targets=support starred expressions as assignment targets

python/python-psi-impl/src/com/jetbrains/python/validation/CompatibilityVisitor.java

@@ -747,6 +747,23 @@ public abstract class CompatibilityVisitor extends PyAnnotator {
                                    matchStatement.getFirstChild());
   }
 
+  @Override
+  public void visitPyTypeAliasStatement(@NotNull PyTypeAliasStatement node) {
+    registerForAllMatchingVersions(level -> level.isOlderThan(LanguageLevel.PYTHON312),
+                                   PyPsiBundle.message("INSP.compatibility.feature.support.type.alias.statements"),
+                                   node);
+  }
+
+  @Override
+  public void visitPyTypeParameterList(@NotNull PyTypeParameterList node) {
+    // No need to report an error inside the statement which is already reported as unsupported
+    if (!(node.getParent() instanceof PyTypeAliasStatement)) {
+      registerForAllMatchingVersions(level -> level.isOlderThan(LanguageLevel.PYTHON312),
+                                     PyPsiBundle.message("INSP.compatibility.feature.support.this.syntax"),
+                                     node);
+    }
+  }
+
   private void checkBitwiseOrUnionSyntax(@NotNull PyBinaryExpression node) {
     if (node.getOperator() != PyTokenTypes.OR) return;
 

python/testData/highlighting/typeAliasStatementBefore312.py

@@ -0,0 +1 @@
+<error descr="Python version 3.11 does not support type alias statements"><info descr="null">type</info> myType[T] = list[T]</error>

python/testData/highlighting/typeParameterListBefore312.py

@@ -0,0 +1,3 @@
+class <info descr="PY.CLASS_DEFINITION">Class</info><error descr="Python version 3.11 does not support this syntax">[T]</error>:
+    def <info descr="PY.FUNC_DEFINITION">foo</info><error descr="Python version 3.11 does not support this syntax">[U]</error>(<info descr="PY.SELF_PARAMETER">x</info>: <info descr="PY.ANNOTATION">U</info>):
+        pass

python/testData/inspections/PyCompatibilityInspection/typeAliasStatements.py

@@ -0,0 +1 @@
+<error descr="Python version 3.11 does not support type alias statements" textAttributesKey="ERRORS_ATTRIBUTES"><warning descr="Python versions 2.7, 3.5, 3.6, 3.7, 3.8, 3.9, 3.10, 3.11 do not support type alias statements" textAttributesKey="WARNING_ATTRIBUTES">type MyType = str</warning></error>

python/testData/inspections/PyCompatibilityInspection/typeParameterLists.py

@@ -0,0 +1,3 @@
+class Clazz<error descr="Python version 3.11 does not support this syntax" textAttributesKey="ERRORS_ATTRIBUTES"><warning descr="Python versions 2.7, 3.5, 3.6, 3.7, 3.8, 3.9, 3.10, 3.11 do not support this syntax" textAttributesKey="WARNING_ATTRIBUTES">[T]</warning></error>:
+    def foo<error descr="Python version 3.11 does not support this syntax" textAttributesKey="ERRORS_ATTRIBUTES"><warning descr="Python versions 2.7, 3.5, 3.6, 3.7, 3.8, 3.9, 3.10, 3.11 do not support this syntax" textAttributesKey="WARNING_ATTRIBUTES">[U]</warning></error>(self):
+        pass

python/testSrc/com/jetbrains/python/PythonHighlightingTest.java

@@ -580,16 +580,26 @@ public class PythonHighlightingTest extends PyTestCase {
     doTest(LanguageLevel.getLatest(), false, true);
   }
 
-  // PY-60767
+  // PY-61856
   public void testTypeAliasStatement() {
     doTest(LanguageLevel.PYTHON312, false, true);
   }
 
-  // PY-60767
+  // PY-61856
   public void testTypeParameter() {
     doTest(LanguageLevel.PYTHON312, false, true);
   }
 
+  // PY-61856
+  public void testTypeAliasStatementBefore312() {
+    doTest(LanguageLevel.PYTHON311, false, true);
+  }
+
+  // PY-61856
+  public void testTypeParameterListBefore312() {
+    doTest(LanguageLevel.PYTHON311, false, true);
+  }
+
   @NotNull
   private static EditorColorsScheme createTemporaryColorScheme() {
     EditorColorsManager manager = EditorColorsManager.getInstance();

python/testSrc/com/jetbrains/python/inspections/PyCompatibilityInspectionTest.java

@@ -270,6 +270,17 @@ public class PyCompatibilityInspectionTest extends PyInspectionTestCase {
     doTest(LanguageLevel.PYTHON311);
   }
 
+  // PY-60767
+  public void testTypeAliasStatements() {
+    doTest(LanguageLevel.PYTHON311);
+  }
+
+  // PY-60767
+  public void testTypeParameterLists() {
+    doTest(LanguageLevel.PYTHON311);
+  }
+
+
   private void doTest(@NotNull LanguageLevel level) {
     runWithLanguageLevel(level, this::doTest);
   }