Merge pull request github#6485 from Marcono1234/marcono1234/field-initializer-fix

Java: Fix Field.getInitializer() matching non-initializer assignments

Author: smowton

java/ql/lib/semmle/code/java/Member.qll

@@ -600,12 +600,13 @@ class Field extends Member, ExprParent, @field, Variable {
 
   /** Gets the initializer expression of this field, if any. */
   override Expr getInitializer() {
-    exists(AssignExpr e, InitializerMethod im |
+    exists(AssignExpr e, InitializerMethod im, ExprStmt exprStmt |
       e.getDest() = this.getAnAccess() and
       e.getSource() = result and
-      pragma[only_bind_out](result).getEnclosingCallable() = im and
-      // This rules out updates in explicit initializer blocks as they are nested inside the compiler generated initializer blocks.
-      pragma[only_bind_out](e.getEnclosingStmt().getParent()) = pragma[only_bind_out](im.getBody())
+      exprStmt.getExpr() = e and
+      // This check also rules out assignments in explicit initializer blocks
+      // (CodeQL models explicit initializer blocks as BlockStmt in initializer methods)
+      exprStmt.getParent() = im.getBody()
     )
   }
 

java/ql/test/library-tests/fields/FieldDecl.expected

@@ -5,3 +5,7 @@
 | fields/FieldTest.java:5:9:5:39 | Object obj, ...; | 1/2 | fields/FieldTest.java:5:35:5:38 | obj2 |
 | fields/FieldTest.java:6:9:6:58 | List<> l, ...; | 0/2 | fields/FieldTest.java:6:54:6:54 | l |
 | fields/FieldTest.java:6:9:6:58 | List<> l, ...; | 1/2 | fields/FieldTest.java:6:57:6:57 | m |
+| fields/FieldTest.java:7:9:7:18 | int x, ...; | 0/1 | fields/FieldTest.java:7:13:7:13 | x |
+| fields/FieldTest.java:8:9:8:22 | int y, ...; | 0/1 | fields/FieldTest.java:8:13:8:13 | y |
+| fields/FieldTest.java:12:9:12:25 | int z, ...; | 0/1 | fields/FieldTest.java:12:20:12:20 | z |
+| fields/FieldTest.java:13:9:13:29 | int w, ...; | 0/1 | fields/FieldTest.java:13:20:13:20 | w |

java/ql/test/library-tests/fields/FieldDeclLocation.expected

@@ -1,3 +1,7 @@
 | List<> l, ...; | 6 | 9 | 6 | 58 |
 | Object obj, ...; | 5 | 9 | 5 | 39 |
 | float ff, ...; | 4 | 9 | 4 | 32 |
+| int w, ...; | 13 | 9 | 13 | 29 |
+| int x, ...; | 7 | 9 | 7 | 18 |
+| int y, ...; | 8 | 9 | 8 | 22 |
+| int z, ...; | 12 | 9 | 12 | 25 |

java/ql/test/library-tests/fields/FieldInitializers.expected

@@ -0,0 +1,6 @@
+| fields/FieldTest.java:4:19:4:19 | g | fields/FieldTest.java:4:23:4:26 | 2.3f |
+| fields/FieldTest.java:5:23:5:25 | obj | fields/FieldTest.java:5:29:5:32 | null |
+| fields/FieldTest.java:7:13:7:13 | x | fields/FieldTest.java:7:17:7:17 | 0 |
+| fields/FieldTest.java:8:13:8:13 | y | fields/FieldTest.java:8:17:8:21 | ...=... |
+| fields/FieldTest.java:12:20:12:20 | z | fields/FieldTest.java:12:24:12:24 | 0 |
+| fields/FieldTest.java:13:20:13:20 | w | fields/FieldTest.java:13:24:13:28 | ...=... |

java/ql/test/library-tests/fields/FieldInitializers.ql

@@ -0,0 +1,4 @@
+import java
+
+from Field f
+select f, f.getInitializer()

java/ql/test/library-tests/fields/FieldLocation.expected

@@ -5,3 +5,7 @@
 | fields/FieldTest.java:5:35:5:38 | obj2 | 5 | 35 | 5 | 38 |
 | fields/FieldTest.java:6:54:6:54 | l | 6 | 54 | 6 | 54 |
 | fields/FieldTest.java:6:57:6:57 | m | 6 | 57 | 6 | 57 |
+| fields/FieldTest.java:7:13:7:13 | x | 7 | 13 | 7 | 13 |
+| fields/FieldTest.java:8:13:8:13 | y | 8 | 13 | 8 | 13 |
+| fields/FieldTest.java:12:20:12:20 | z | 12 | 20 | 12 | 20 |
+| fields/FieldTest.java:13:20:13:20 | w | 13 | 20 | 13 | 20 |

java/ql/test/library-tests/fields/PrintAst.expected

@@ -12,3 +12,29 @@ fields/FieldTest.java:
 #    6|         1: [Annotation] SuppressWarnings
 #    6|           1: [StringLiteral] "rawtypes"
 #    6|       -1: [TypeAccess] List<>
+#    7|     7: [FieldDeclaration] int x, ...;
+#    7|       -1: [TypeAccess] int
+#    7|       0: [IntegerLiteral] 0
+#    8|     8: [FieldDeclaration] int y, ...;
+#    8|       -1: [TypeAccess] int
+#    8|       0: [AssignExpr] ...=...
+#    8|         0: [VarAccess] x
+#    8|         1: [IntegerLiteral] 1
+#    9|     9: [BlockStmt] { ... }
+#   10|       0: [ExprStmt] <Expr>;
+#   10|         0: [AssignExpr] ...=...
+#   10|           0: [VarAccess] x
+#   10|           1: [IntegerLiteral] 2
+#   12|     10: [FieldDeclaration] int z, ...;
+#   12|       -1: [TypeAccess] int
+#   12|       0: [IntegerLiteral] 0
+#   13|     11: [FieldDeclaration] int w, ...;
+#   13|       -1: [TypeAccess] int
+#   13|       0: [AssignExpr] ...=...
+#   13|         0: [VarAccess] z
+#   13|         1: [IntegerLiteral] 1
+#   14|     12: [BlockStmt] { ... }
+#   15|       0: [ExprStmt] <Expr>;
+#   15|         0: [AssignExpr] ...=...
+#   15|           0: [VarAccess] z
+#   15|           1: [IntegerLiteral] 2

java/ql/test/library-tests/fields/fields/FieldTest.java

@@ -4,4 +4,14 @@ public class FieldTest {
         float ff, g = 2.3f, hhh;
         static Object obj = null, obj2;
         @SuppressWarnings("rawtypes") java.util.List l, m;
+        int x = 0;
+        int y = x = 1;
+        {
+                x = 2; // Shouldn't show up as an initializer
+        }
+        static int z = 0;
+        static int w = z = 1;
+        static {
+                z = 2; // Shouldn't show up as an initializer
+        }
 }