TS: fix extraction of binding pattern with default

Author: asger-semmle

javascript/extractor/src/com/semmle/js/parser/TypeScriptASTConverter.java

@@ -1612,7 +1612,7 @@ private Node convertObjectBindingPattern(JsonObject node,
 			if (hasChild(element, "dotDotDotToken")) {
 				propVal = new RestElement(eltLoc, propKey);
 			} else if (hasChild(element, "initializer")) {
-				propVal = new AssignmentPattern(eltLoc, "=", propKey, convertChild(element, "initializer"));
+				propVal = new AssignmentPattern(eltLoc, "=", convertChild(element, "name"), convertChild(element, "initializer"));
 			} else {
 				propVal = convertChild(element, "name");
 			}

javascript/ql/test/library-tests/TypeScript/BindingPattern/VarDecl.expected

@@ -0,0 +1,3 @@
+| tst.tsx:1:10:1:10 | f |
+| tst.tsx:1:12:1:12 | o |
+| tst.tsx:2:14:2:14 | v |

javascript/ql/test/library-tests/TypeScript/BindingPattern/VarDecl.ql

@@ -0,0 +1,4 @@
+import javascript
+
+from VarDecl decl
+select decl

javascript/ql/test/library-tests/TypeScript/BindingPattern/tst.tsx

@@ -0,0 +1,4 @@
+function f(o) {
+  const { p: v = [] } = o;
+  return v;
+}