Final Local Variable Check, fixed false-positive, issue #258

alexkravin · alexkravin · commit f565eb287842 · 2015-01-26T14:16:49.000+04:00
diff --git a/src/main/java/com/puppycrawl/tools/checkstyle/checks/coding/FinalLocalVariableCheck.java b/src/main/java/com/puppycrawl/tools/checkstyle/checks/coding/FinalLocalVariableCheck.java
@@ -109,7 +109,8 @@ public void visitToken(DetailAST ast)
                 }
             case TokenTypes.VARIABLE_DEF:
                 if ((ast.getParent().getType() != TokenTypes.OBJBLOCK)
-                    && (ast.getParent().getType() != TokenTypes.FOR_EACH_CLAUSE))
+                    && (ast.getParent().getType() != TokenTypes.FOR_EACH_CLAUSE)
+                    && isFirstVariableInForInit(ast))
                 {
                     insertVariable(ast);
                 }
@@ -146,6 +147,25 @@ public void visitToken(DetailAST ast)
         }
     }
 
+    /**
+     * Checks if current variable is defined first in
+     *  {@link TokenTypes#FOR_INIT for-loop init}, e.g.:
+     * <p>
+     * <code>
+     * for (int i = 0, j = 0; i < j; i++) { . . . }
+     * </code>
+     * </p>
+     * <code>i</code> is first variable in {@link TokenTypes#FOR_INIT for-loop init}
+     * @param variableDef variable definition node.
+     * @return true if variableDef is first variable in {@link TokenTypes#FOR_INIT for-loop init}
+     */
+    private static boolean isFirstVariableInForInit(DetailAST variableDef)
+    {
+        return variableDef.getParent().getType() != TokenTypes.FOR_INIT
+                 || variableDef.getPreviousSibling() == null
+                 || variableDef.getPreviousSibling().getType() != TokenTypes.COMMA;
+    }
+
     /**
      * Determines whether an AST is a descendant of an abstract or native method.
      * @param ast the AST to check.
diff --git a/src/test/java/com/puppycrawl/tools/checkstyle/checks/coding/FinalLocalVariableCheckTest.java b/src/test/java/com/puppycrawl/tools/checkstyle/checks/coding/FinalLocalVariableCheckTest.java
@@ -82,4 +82,17 @@ public void testNativeMethods() throws Exception
         };
         verify(checkConfig, getPath("coding/InputFinalLocalVariableNativeMethods.java"), expected);
     }
+
+    @Test
+    public void testFalsePositive() throws Exception
+    {
+        final DefaultConfiguration checkConfig =
+            createCheckConfig(FinalLocalVariableCheck.class);
+        checkConfig.addAttribute("tokens", "VARIABLE_DEF, PARAMETER_DEF");
+
+        final String[] expected = {
+
+        };
+        verify(checkConfig, getPath("coding/InputFinalLocalVariableCheckFalsePositive.java"), expected);
+    }
 }
diff --git a/src/test/resources/com/puppycrawl/tools/checkstyle/coding/InputFinalLocalVariableCheckFalsePositive.java b/src/test/resources/com/puppycrawl/tools/checkstyle/coding/InputFinalLocalVariableCheckFalsePositive.java
@@ -0,0 +1,13 @@
+package com.puppycrawl.tools.checkstyle.coding;
+
+public class InputFinalLocalVariableCheckFalsePositive
+{
+    public void method()
+    {
+        final java.util.List<Object> list = new java.util.ArrayList<>();
+
+        for ( int i = 0, s0 = list.size(); i < s0; i++ )
+        {
+        }
+    }
+}
