report colon with no following statement list as error (PY-2790)

python/src/com/jetbrains/python/parsing/StatementParsing.java

@@ -714,8 +714,13 @@ public class StatementParsing extends Parsing implements ITokenTypeRemapper {
       }
       else {
         myBuilder.advanceLexer();
-        while (!myBuilder.eof() && myBuilder.getTokenType() != PyTokenTypes.DEDENT) {
-          parseStatement();
+        if (myBuilder.eof()) {
+          myBuilder.error("indented block expected");
+        }
+        else {
+          while (!myBuilder.eof() && myBuilder.getTokenType() != PyTokenTypes.DEDENT) {
+            parseStatement();
+          }
         }
       }
 
@@ -734,11 +739,16 @@ public class StatementParsing extends Parsing implements ITokenTypeRemapper {
     }
     else {
       final PsiBuilder.Marker marker = myBuilder.mark();
-      parseSimpleStatement(true);
-      while (matchToken(PyTokenTypes.SEMICOLON)) {
-        if (matchToken(PyTokenTypes.STATEMENT_BREAK))
-          break;
+      if (myBuilder.eof()) {
+        myBuilder.error("statement expected");
+      }
+      else {
         parseSimpleStatement(true);
+        while (matchToken(PyTokenTypes.SEMICOLON)) {
+          if (matchToken(PyTokenTypes.STATEMENT_BREAK))
+            break;
+          parseSimpleStatement(true);
+        }
       }
       marker.done(PyElementTypes.STATEMENT_LIST);
       if (endMarker != null) {

python/testData/psi/ColonBeforeEof.py

@@ -0,0 +1 @@
+for a in b:

python/testData/psi/ColonBeforeEof.txt

@@ -0,0 +1,16 @@
+PyFile:ColonBeforeEof.py
+  PyForStatement
+    PyForPart
+      PsiElement(Py:FOR_KEYWORD)('for')
+      PsiWhiteSpace(' ')
+      PyTargetExpression: a
+        PsiElement(Py:IDENTIFIER)('a')
+      PsiWhiteSpace(' ')
+      PsiElement(Py:IN_KEYWORD)('in')
+      PsiWhiteSpace(' ')
+      PyReferenceExpression: b
+        PsiElement(Py:IDENTIFIER)('b')
+      PsiElement(Py:COLON)(':')
+      PyStatementList
+        PsiErrorElement:statement expected
+          <empty list>

python/testSrc/com/jetbrains/python/PythonParsingTest.java

@@ -251,6 +251,10 @@ public class PythonParsingTest extends ParsingTestCase {
     doTest();
   }
 
+  public void testColonBeforeEof() {  // PY-2790
+    doTest();
+  }
+
   public void doTest() {
     doTest(LanguageLevel.PYTHON25);
   }