Fixed resolving '/' to __truediv__ when available (PY-5499, PY-4460)

python/src/com/jetbrains/python/PyNames.java

@@ -82,6 +82,8 @@ public class PyNames {
   public static final String DELITEM = "__delitem__";
   public static final String POS = "__pos__";
   public static final String NEG = "__neg__";
+  public static final String DIV = "__div__";
+  public static final String TRUEDIV = "__truediv__";
 
   public static final String NAME = "__name__";
   public static final String ENTER = "__enter__";
@@ -91,7 +93,7 @@ public class PyNames {
   public static final String COLLECTIONS_PY = "collections.py";
 
   public static final String SET = "set";
-  
+
   public static final String KEYS = "keys";
 
   public static final String PASS = "pass";
@@ -267,7 +269,7 @@ public class PyNames {
   // canonical names, not forced by interpreter
   public static final String CANONICAL_SELF = "self";
   public static final String BASESTRING = "basestring";
-  
+
   /**
    * Contains keywords as of CPython 2.5.
    */
@@ -324,7 +326,7 @@ public class PyNames {
    * @return true iff name is not reserved and is a well-formed identifier.
    */
   public static boolean isIdentifier(@NotNull @NonNls String name) {
-    return ! isReserved(name) && IDENTIFIER_PATTERN.matcher(name).matches(); 
+    return ! isReserved(name) && IDENTIFIER_PATTERN.matcher(name).matches();
   }
 
   public static boolean isRightOperatorName(@Nullable String name) {

python/src/com/jetbrains/python/psi/impl/references/PyOperatorReference.java

@@ -2,6 +2,7 @@ package com.jetbrains.python.psi.impl.references;
 
 import com.intellij.openapi.vfs.VirtualFile;
 import com.intellij.psi.PsiElement;
+import com.intellij.psi.PsiFile;
 import com.jetbrains.python.PyNames;
 import com.jetbrains.python.psi.*;
 import com.jetbrains.python.psi.resolve.PyResolveContext;
@@ -35,23 +36,10 @@ public class PyOperatorReference extends PyReferenceImpl {
         res = resolveMember(expr.getRightExpression(), name);
       }
       else {
-        final TypeEvalContext typeEvalContext = myContext.getTypeEvalContext();
-        typeEvalContext.trace("Trying to resolve left operator");
-        typeEvalContext.traceIndent();
-        try {
-          res.addAll(resolveMember(expr.getLeftExpression(), name));
-        }
-        finally {
-          typeEvalContext.traceUnindent();
-        }
-        typeEvalContext.trace("Trying to resolve right operator");
-        typeEvalContext.traceIndent();
-        try {
-          res.addAll(resolveMember(expr.getRightExpression(), leftToRightOperatorName(name)));
-        }
-        finally {
-           typeEvalContext.traceUnindent();
+        if (PyNames.DIV.equals(name) && isTrueDivEnabled(myElement)) {
+          resolveLeftAndRightOperators(res, expr, PyNames.TRUEDIV);
         }
+        resolveLeftAndRightOperators(res, expr, name);
       }
     }
     else if (myElement instanceof PySubscriptionExpression) {
@@ -92,6 +80,35 @@ public class PyOperatorReference extends PyReferenceImpl {
     return name.replaceFirst("__([a-z]+)__", "__r$1__");
   }
 
+  private static boolean isTrueDivEnabled(@NotNull PyElement anchor) {
+    final PsiFile file = anchor.getContainingFile();
+    if (file instanceof PyFile) {
+      final PyFile pyFile = (PyFile)file;
+      return FutureFeature.DIVISION.requiredAt(pyFile.getLanguageLevel()) || pyFile.hasImportFromFuture(FutureFeature.DIVISION);
+    }
+    return false;
+  }
+
+  private void resolveLeftAndRightOperators(List<RatedResolveResult> res, PyBinaryExpression expr, String name) {
+    final TypeEvalContext typeEvalContext = myContext.getTypeEvalContext();
+    typeEvalContext.trace("Trying to resolve left operator");
+    typeEvalContext.traceIndent();
+    try {
+      res.addAll(resolveMember(expr.getLeftExpression(), name));
+    }
+    finally {
+      typeEvalContext.traceUnindent();
+    }
+    typeEvalContext.trace("Trying to resolve right operator");
+    typeEvalContext.traceIndent();
+    try {
+      res.addAll(resolveMember(expr.getRightExpression(), leftToRightOperatorName(name)));
+    }
+    finally {
+      typeEvalContext.traceUnindent();
+    }
+  }
+
   @NotNull
   private List<RatedResolveResult> resolveMember(@Nullable PyExpression object, @Nullable String name) {
     final ArrayList<RatedResolveResult> results = new ArrayList<RatedResolveResult>();

python/testData/resolve/TrueDiv.py

@@ -0,0 +1,3 @@
+def test(x):
+    return 1 / x
+#            <ref>

python/testSrc/com/jetbrains/python/Py3ResolveTest.java

@@ -40,4 +40,9 @@ public class Py3ResolveTest extends PyResolveTestCase {
   public void testObjectMethods() {  // PY-1494
     assertResolvesTo(PyFunction.class, "__repr__");
   }
+
+  // PY-5499
+  public void testTrueDiv() {
+    assertResolvesTo(PyFunction.class, "__truediv__");
+  }
 }