diff --git a/python/src/com/jetbrains/python/parsing/ExpressionParsing.java b/python/src/com/jetbrains/python/parsing/ExpressionParsing.java
index 9a7e343307cd..3f5f17e3e3b3 100644
--- a/python/src/com/jetbrains/python/parsing/ExpressionParsing.java
+++ b/python/src/com/jetbrains/python/parsing/ExpressionParsing.java
@@ -99,7 +99,7 @@ public class ExpressionParsing extends Parsing {
       builder.error(message("PARSE.expected.expression"));
     }
     if (builder.getTokenType() == PyTokenTypes.FOR_KEYWORD) {
-      parseComprehension(expr, PyTokenTypes.RBRACKET, PyElementTypes.LIST_COMP_EXPRESSION);
+      parseComprehension(expr, PyTokenTypes.RBRACKET, PyElementTypes.LIST_COMP_EXPRESSION, false);
     }
     else {
       while (builder.getTokenType() != PyTokenTypes.RBRACKET) {
@@ -120,8 +120,9 @@ public class ExpressionParsing extends Parsing {
   }
 
   private void parseComprehension(PsiBuilder.Marker expr,
-                                       final IElementType endToken,
-                                       final IElementType exprType) {
+                                  final IElementType endToken,
+                                  final IElementType exprType,
+                                  final boolean leaveEndTokenOutside) {
     assertCurrentToken(PyTokenTypes.FOR_KEYWORD);
     while (true) {
       myBuilder.advanceLexer();
@@ -134,8 +135,13 @@ public class ExpressionParsing extends Parsing {
         myBuilder.advanceLexer();
         parseOldExpression();
       }
-      if (myBuilder.getTokenType() == endToken) {
-        myBuilder.advanceLexer();
+      if (atToken(endToken)) {
+        if (leaveEndTokenOutside) {
+          expr.done(exprType);
+          nextToken();
+          return;
+        }
+        nextToken();
         break;
       }
       if (myBuilder.getTokenType() == PyTokenTypes.FOR_KEYWORD) {
@@ -176,7 +182,7 @@ public class ExpressionParsing extends Parsing {
     }
     else if (atToken(PyTokenTypes.FOR_KEYWORD)) {
       firstExprMarker.drop();
-      parseComprehension(expr, PyTokenTypes.RBRACE, PyElementTypes.SET_COMP_EXPRESSION);
+      parseComprehension(expr, PyTokenTypes.RBRACE, PyElementTypes.SET_COMP_EXPRESSION, false);
     }
     else {
       myBuilder.error("expression expected");
@@ -197,7 +203,7 @@ public class ExpressionParsing extends Parsing {
     }
     firstKeyValueMarker.done(PyElementTypes.KEY_VALUE_EXPRESSION);
     if (myBuilder.getTokenType() == PyTokenTypes.FOR_KEYWORD) {
-      parseComprehension(startMarker, PyTokenTypes.RBRACE, PyElementTypes.DICT_COMP_EXPRESSION);
+      parseComprehension(startMarker, PyTokenTypes.RBRACE, PyElementTypes.DICT_COMP_EXPRESSION, false);
     }
     else {
       while (myBuilder.getTokenType() != PyTokenTypes.RBRACE) {
@@ -249,7 +255,7 @@ public class ExpressionParsing extends Parsing {
     else {
       parseYieldOrTupleExpression(isTargetExpression);
       if (myBuilder.getTokenType() == PyTokenTypes.FOR_KEYWORD) {
-        parseComprehension(expr, PyTokenTypes.RPAR, PyElementTypes.GENERATOR_EXPRESSION);
+        parseComprehension(expr, PyTokenTypes.RPAR, PyElementTypes.GENERATOR_EXPRESSION, false);
       }
       else {
         checkMatches(PyTokenTypes.RPAR, message("PARSE.expected.rpar"));
@@ -409,15 +415,15 @@ public class ExpressionParsing extends Parsing {
   public void parseArgumentList() {
     LOG.assertTrue(myBuilder.getTokenType() == PyTokenTypes.LPAR);
     final PsiBuilder.Marker arglist = myBuilder.mark();
-    final PsiBuilder.Marker genexpr = myBuilder.mark();
     myBuilder.advanceLexer();
+    final PsiBuilder.Marker genexpr = myBuilder.mark();
     int argNumber = 0;
     boolean needBracket = true;
     while (myBuilder.getTokenType() != PyTokenTypes.RPAR) {
       argNumber++;
       if (argNumber > 1) {
         if (argNumber == 2 && myBuilder.getTokenType() == PyTokenTypes.FOR_KEYWORD && genexpr != null) {
-          parseComprehension(genexpr, PyTokenTypes.RPAR, PyElementTypes.GENERATOR_EXPRESSION);
+          parseComprehension(genexpr, PyTokenTypes.RPAR, PyElementTypes.GENERATOR_EXPRESSION, true);
           needBracket = false;
           break;
         }
diff --git a/python/testData/formatter/noWrapBeforeParen.py b/python/testData/formatter/noWrapBeforeParen.py
new file mode 100644
index 000000000000..9f7839338079
--- /dev/null
+++ b/python/testData/formatter/noWrapBeforeParen.py
@@ -0,0 +1,6 @@
+def foo():
+    def bar():
+        def baz():
+            if comments:
+                for comment in comments:
+                    record += '    <comment ' + "".join(ca + '=' + quoteattr(comment[ca]) + ' ' for ca in comment) + '/>\n'
\ No newline at end of file
diff --git a/python/testData/formatter/noWrapBeforeParen_after.py b/python/testData/formatter/noWrapBeforeParen_after.py
new file mode 100644
index 000000000000..61f5d746a00e
--- /dev/null
+++ b/python/testData/formatter/noWrapBeforeParen_after.py
@@ -0,0 +1,7 @@
+def foo():
+    def bar():
+        def baz():
+            if comments:
+                for comment in comments:
+                    record += '    <comment ' + "".join(
+                        ca + '=' + quoteattr(comment[ca]) + ' ' for ca in comment) + '/>\n'
\ No newline at end of file
diff --git a/python/testData/psi/GeneratorInArgumentList.py b/python/testData/psi/GeneratorInArgumentList.py
new file mode 100644
index 000000000000..c0e4b32d9ebe
--- /dev/null
+++ b/python/testData/psi/GeneratorInArgumentList.py
@@ -0,0 +1 @@
+"".join(' ' for ca in comment)
\ No newline at end of file
diff --git a/python/testData/psi/GeneratorInArgumentList.txt b/python/testData/psi/GeneratorInArgumentList.txt
new file mode 100644
index 000000000000..0a15e9a61b27
--- /dev/null
+++ b/python/testData/psi/GeneratorInArgumentList.txt
@@ -0,0 +1,24 @@
+PyFile:GeneratorInArgumentList.py
+  PyExpressionStatement
+    PyCallExpression: "".join
+      PyReferenceExpression: join
+        PyStringLiteralExpression: 
+          PsiElement(Py:STRING_LITERAL)('""')
+        PsiElement(Py:DOT)('.')
+        PsiElement(Py:IDENTIFIER)('join')
+      PyArgumentList
+        PsiElement(Py:LPAR)('(')
+        PyGeneratorExpression
+          PyStringLiteralExpression:  
+            PsiElement(Py:STRING_LITERAL)('' '')
+          PsiWhiteSpace(' ')
+          PsiElement(Py:FOR_KEYWORD)('for')
+          PsiWhiteSpace(' ')
+          PyTargetExpression: ca
+            PsiElement(Py:IDENTIFIER)('ca')
+          PsiWhiteSpace(' ')
+          PsiElement(Py:IN_KEYWORD)('in')
+          PsiWhiteSpace(' ')
+          PyReferenceExpression: comment
+            PsiElement(Py:IDENTIFIER)('comment')
+        PsiElement(Py:RPAR)(')')
\ No newline at end of file
diff --git a/python/testSrc/com/jetbrains/python/PyFormatterTest.java b/python/testSrc/com/jetbrains/python/PyFormatterTest.java
index ecb58ad554ae..c11e9395ba30 100644
--- a/python/testSrc/com/jetbrains/python/PyFormatterTest.java
+++ b/python/testSrc/com/jetbrains/python/PyFormatterTest.java
@@ -104,6 +104,10 @@ public class PyFormatterTest extends PyLightFixtureTestCase {
     doTest();
   }
 
+  public void testNoWrapBeforeParen() {  // PY-3172
+    doTest();
+  }
+
   private void doTest() {
     myFixture.configureByFile("formatter/" + getTestName(true) + ".py");
     ApplicationManager.getApplication().runWriteAction(new Runnable() {
diff --git a/python/testSrc/com/jetbrains/python/PythonParsingTest.java b/python/testSrc/com/jetbrains/python/PythonParsingTest.java
index 9656fcd6290c..bfcd853a8add 100644
--- a/python/testSrc/com/jetbrains/python/PythonParsingTest.java
+++ b/python/testSrc/com/jetbrains/python/PythonParsingTest.java
@@ -255,6 +255,10 @@ public class PythonParsingTest extends ParsingTestCase {
     doTest();
   }
 
+  public void testGeneratorInArgumentList() {  // PY-3172
+    doTest();
+  }
+
   public void doTest() {
     doTest(LanguageLevel.PYTHON25);
   }