PY-56268/PY-84930 go to type declaration: support callables

GitOrigin-RevId: d5e05b87ff1fc5670dfdeca7b13c6aee4661a519

python/src/com/jetbrains/python/codeInsight/PyTypeDeclarationProvider.kt

@@ -4,6 +4,8 @@ package com.jetbrains.python.codeInsight
 import com.intellij.codeInsight.navigation.actions.TypeDeclarationProvider
 import com.intellij.psi.PsiElement
 import com.jetbrains.python.psi.PyTypedElement
+import com.jetbrains.python.psi.types.PyCallableType
+import com.jetbrains.python.psi.types.PyClassType
 import com.jetbrains.python.psi.types.PyTypeUtil.componentSequence
 import com.jetbrains.python.psi.types.TypeEvalContext
 
@@ -12,7 +14,15 @@ class PyTypeDeclarationProvider : TypeDeclarationProvider {
   override fun getSymbolTypeDeclarations(symbol: PsiElement): Array<out PsiElement>? {
     if (symbol is PyTypedElement) {
       val context = TypeEvalContext.userInitiated(symbol.project, symbol.containingFile)
-      return context.getType(symbol).componentSequence
+
+      // When the symbol is a function,
+      // navigate to the return type declaration instead of the function type itself.
+      val type = when (val type = context.getType(symbol)) {
+        is PyCallableType if type !is PyClassType -> type.getReturnType(context)
+        else -> type
+      }
+
+      return type.componentSequence
         .filterNotNull()
         .mapNotNull { it.declarationElement }
         .distinct()

python/testSrc/com/jetbrains/python/testing/PyTestFixtureResolvingTest.kt

@@ -1,12 +1,15 @@
 // Copyright 2000-2023 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
 package com.jetbrains.python.testing
 
+import com.intellij.codeInsight.navigation.actions.GotoTypeDeclarationAction
+import com.intellij.idea.TestFor
 import com.intellij.psi.PsiElement
 import com.intellij.psi.PsiPolyVariantReference
 import com.intellij.psi.PsiReference
 import com.intellij.psi.ResolveResult
 import com.jetbrains.python.fixture.PythonCommonTestCase
 import com.jetbrains.python.fixtures.PyTestCase
+import com.jetbrains.python.psi.PyFile
 import com.jetbrains.python.psi.PyNamedParameter
 import com.jetbrains.python.psi.resolve.ImportedResolveResult
 import com.jetbrains.python.psi.types.TypeEvalContext
@@ -360,4 +363,27 @@ class PyTestFixtureResolvingTest : PyTestCase() {
   fun testNamedParameterTypes() {
     assertCorrectType(PARAMETRIZED_DIR, TEST_PARAMETER_TYPES, INT_STR_UNION)
   }
+
+  @TestFor(issues = ["PY-56268"])
+  fun `test goto type declaration for fixture parameter`() {
+    myFixture.configureByText("test.py", """
+      import pytest
+
+
+      class A: pass
+      
+      
+      @pytest.fixture
+      def instance():
+          return A()
+      
+      
+      def test(inst<caret>ance):
+          assert instance
+      """)
+    val types = GotoTypeDeclarationAction.findSymbolTypes(myFixture.editor, myFixture.caretOffset)
+    assertNotNull("Go to Type Declaration should resolve the fixture parameter type", types)
+    assertEquals(1, types!!.size)
+    assertEquals((myFixture.file as PyFile).findTopLevelClass("A"), types.single())
+  }
 }