From c2a45c64caad35aed004ea8c8fd95979c8ae2460 Mon Sep 17 00:00:00 2001
From: Andreas Dangel <andreas.dangel@pmd-code.org>
Date: Sat, 29 Jun 2019 15:01:24 +0200
Subject: [PATCH] [java] CloseResource: verify first argument for chained
 streams

---
 .../rule/errorprone/CloseResourceRule.java    | 19 +++++++++++++-
 .../rule/errorprone/xml/CloseResource.xml     | 25 +++++++++++++++++++
 2 files changed, 43 insertions(+), 1 deletion(-)

diff --git a/pmd-java/src/main/java/net/sourceforge/pmd/lang/java/rule/errorprone/CloseResourceRule.java b/pmd-java/src/main/java/net/sourceforge/pmd/lang/java/rule/errorprone/CloseResourceRule.java
index 589825fe01..d51bda2cc0 100644
--- a/pmd-java/src/main/java/net/sourceforge/pmd/lang/java/rule/errorprone/CloseResourceRule.java
+++ b/pmd-java/src/main/java/net/sourceforge/pmd/lang/java/rule/errorprone/CloseResourceRule.java
@@ -42,7 +42,9 @@ import net.sourceforge.pmd.lang.java.ast.ASTVariableDeclaratorId;
 import net.sourceforge.pmd.lang.java.ast.ASTVariableInitializer;
 import net.sourceforge.pmd.lang.java.ast.TypeNode;
 import net.sourceforge.pmd.lang.java.rule.AbstractJavaRule;
+import net.sourceforge.pmd.lang.java.symboltable.VariableNameDeclaration;
 import net.sourceforge.pmd.lang.java.typeresolution.TypeHelper;
+import net.sourceforge.pmd.lang.symboltable.NameOccurrence;
 import net.sourceforge.pmd.properties.PropertyDescriptor;
 
 /**
@@ -187,10 +189,25 @@ public class CloseResourceRule extends AbstractJavaRule {
 
     private ASTExpression getAllocationFirstArgument(ASTExpression expression) {
         List<ASTAllocationExpression> allocations = expression.findDescendantsOfType(ASTAllocationExpression.class);
+        ASTExpression firstArgument = null;
+
         if (!allocations.isEmpty()) {
             ASTArgumentList argumentList = allocations.get(allocations.size() - 1).getFirstDescendantOfType(ASTArgumentList.class);
             if (argumentList != null) {
-                return argumentList.getFirstChildOfType(ASTExpression.class);
+                firstArgument = argumentList.getFirstChildOfType(ASTExpression.class);
+            }
+        }
+
+        // the argument must not be a literal, it needs to be a Name referring to a variable
+        if (firstArgument != null && firstArgument.getFirstDescendantOfType(ASTName.class) != null) {
+            ASTName name = firstArgument.getFirstDescendantOfType(ASTName.class);
+
+            Map<VariableNameDeclaration, List<NameOccurrence>> vars = firstArgument.getScope()
+                    .getDeclarations(VariableNameDeclaration.class);
+            for (VariableNameDeclaration nameDecl : vars.keySet()) {
+                if (nameDecl.getName().equals(name.getImage())) {
+                    return firstArgument;
+                }
             }
         }
         return null;
diff --git a/pmd-java/src/test/resources/net/sourceforge/pmd/lang/java/rule/errorprone/xml/CloseResource.xml b/pmd-java/src/test/resources/net/sourceforge/pmd/lang/java/rule/errorprone/xml/CloseResource.xml
index 95c8409c30..98df84b9f8 100644
--- a/pmd-java/src/test/resources/net/sourceforge/pmd/lang/java/rule/errorprone/xml/CloseResource.xml
+++ b/pmd-java/src/test/resources/net/sourceforge/pmd/lang/java/rule/errorprone/xml/CloseResource.xml
@@ -1038,6 +1038,31 @@ public class CloseResourcePrintWriter {
         pw.println("Foo");
         return sw.toString();
     }
+}
+        ]]></code>
+    </test-code>
+
+    <test-code>
+        <description>Correctly determine the type for the message</description>
+        <expected-problems>2</expected-problems>
+        <expected-linenumbers>7,8</expected-linenumbers>
+        <expected-messages>
+            <message>Ensure that resources like this FileInputStream object are closed after use</message>
+            <message>Ensure that resources like this Scanner object are closed after use</message>
+        </expected-messages>
+        <code><![CDATA[
+import java.io.*;
+import java.util.Scanner;
+
+public class CloseResourceCase {
+    public void run() {
+        try {
+            FileInputStream in = new FileInputStream("MyFile.txt");
+            Scanner input = new Scanner(System.in, "utf-8");
+        } catch (Exception e) {
+            e.printStackTrace();
+        }
+    }
 }
         ]]></code>
     </test-code>