Hardened type resolution checks in QueryParameterizer (#289)

Also updated the README to mention docker for running tests.

Author: andrecsilva

README.md

@@ -50,6 +50,8 @@ python -m site
 ./gradlew check
 ```
 
+You need to be able to run [Docker](https://www.docker.com/) for some tests. Make sure you have it installed and have the necessary permissions to run with your user.
+
 ### Run the Core Codemods
 You can download and run the latest release from this repository in order to run the core codemods as a CLI:
 

core-codemods/src/main/java/io/codemodder/codemods/QueryParameterizer.java

@@ -5,12 +5,14 @@
 import com.github.javaparser.ast.expr.Expression;
 import com.github.javaparser.ast.expr.NameExpr;
 import com.github.javaparser.ast.expr.StringLiteralExpr;
+import com.github.javaparser.resolution.types.ResolvedType;
 import io.codemodder.ast.ASTs;
 import io.codemodder.ast.LocalVariableDeclaration;
 import java.util.ArrayDeque;
 import java.util.ArrayList;
 import java.util.Deque;
 import java.util.List;
+import java.util.Optional;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
 
@@ -51,6 +53,14 @@ List<Deque<Expression>> getInjections() {
     return injections;
   }
 
+  private Optional<ResolvedType> calculateResolvedType(final Expression e) {
+    try {
+      return Optional.of(e.calculateResolvedType());
+    } catch (final RuntimeException exception) {
+      return Optional.empty();
+    }
+  }
+
   /**
    * Finds the leaves of an expression tree whose internal nodes are BinaryExpr, EnclosedExpr and
    * NameExpr. Anything else is considered a leaf. Returns a Stream containing the leaves in
@@ -59,9 +69,11 @@ List<Deque<Expression>> getInjections() {
   private Stream<Expression> findLeaves(final Expression e) {
     // EnclosedExpr and BinaryExpr are considered as internal nodes, so we recurse
     if (e instanceof EnclosedExpr) {
-      if (e.calculateResolvedType().describe().equals("java.lang.String"))
+      if (calculateResolvedType(e)
+          .filter(rt -> rt.describe().equals("java.lang.String"))
+          .isPresent()) {
         return findLeaves(e.asEnclosedExpr().getInner());
-      else {
+      } else {
         return Stream.of(e);
       }
     }
@@ -74,7 +86,9 @@ else if (e instanceof BinaryExpr
     }
     // NameExpr of String types should be recursively searched for more expressions.
     else if (e instanceof NameExpr
-        && e.calculateResolvedType().describe().equals("java.lang.String")) {
+        && calculateResolvedType(e)
+            .filter(rt -> rt.describe().equals("java.lang.String"))
+            .isPresent()) {
       // TODO consider fields and extract inits if any
       final var maybeSourceLVD =
           ASTs.findEarliestLocalVariableDeclarationOf(e, e.asNameExpr().getNameAsString())
@@ -152,7 +166,11 @@ private boolean convertibleToString(final Expression exp) {
     // See
     // https://download.oracle.com/otn-pub/jcp/jdbc-4_2-mrel2-spec/jdbc4.2-fr-spec.pdf
     // for type conversions by setObject
-    final var type = exp.calculateResolvedType();
+    final var typeRef = calculateResolvedType(exp);
+    if (typeRef.isEmpty()) {
+      return false;
+    }
+    final var type = typeRef.get();
 
     // primitive type?
     if (type.isPrimitive()) return false;