Merge pull request github#3304 from asger-semmle/js/typescript-unary-type-expr

Approved by erik-krogh

Author: semmle-qlci

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

@@ -1588,7 +1588,16 @@ private Node convertLabeledStatement(JsonObject node, SourceLocation loc) throws
   }
 
   private Node convertLiteralType(JsonObject node, SourceLocation loc) throws ParseError {
-    return convertChild(node, "literal");
+    Node literal = convertChild(node, "literal");
+    // Convert a negated literal to a negative number
+    if (literal instanceof UnaryExpression) {
+      UnaryExpression unary = (UnaryExpression) literal;
+      if (unary.getOperator().equals("-") && unary.getArgument() instanceof Literal) {
+        Literal arg = (Literal) unary.getArgument();
+        literal = new Literal(loc, arg.getTokenType(), "-" + arg.getValue());
+      }
+    }
+    return literal;
   }
 
   private Node convertMappedType(JsonObject node, SourceLocation loc) throws ParseError {

javascript/ql/test/library-tests/TypeScript/RegressionTests/NegativeNumberType/test.expected

@@ -0,0 +1 @@
+| tst.ts:1:25:1:26 | -1 | -1 | -1 |

javascript/ql/test/library-tests/TypeScript/RegressionTests/NegativeNumberType/test.ql

@@ -0,0 +1,4 @@
+import javascript
+
+from NumberLiteralTypeExpr t
+select t, t.getValue(), t.getIntValue()

javascript/ql/test/library-tests/TypeScript/RegressionTests/NegativeNumberType/tsconfig.json

@@ -0,0 +1,3 @@
+{
+    "include": ["."]
+}

javascript/ql/test/library-tests/TypeScript/RegressionTests/NegativeNumberType/tst.ts

@@ -0,0 +1 @@
+type Foo<T> = T extends -1 ? true : false;