improve mocha tests (#3195)

test/mocha/tokens.js

@@ -0,0 +1,26 @@
+var assert = require("assert");
+var UglifyJS = require("../..");
+
+describe("tokens", function() {
+    it("Should give correct positions for accessors", function() {
+        // location               0         1         2         3         4
+        //                        01234567890123456789012345678901234567890123456789
+        var ast = UglifyJS.parse("var obj = { get latest() { return undefined; } }");
+        // test all AST_ObjectProperty tokens are set as expected
+        var found = false;
+        ast.walk(new UglifyJS.TreeWalker(function(node) {
+            if (node instanceof UglifyJS.AST_ObjectProperty) {
+                found = true;
+                assert.equal(node.start.pos, 12);
+                assert.equal(node.end.endpos, 46);
+                assert(node.key instanceof UglifyJS.AST_SymbolAccessor);
+                assert.equal(node.key.start.pos, 16);
+                assert.equal(node.key.end.endpos, 22);
+                assert(node.value instanceof UglifyJS.AST_Accessor);
+                assert.equal(node.value.start.pos, 22);
+                assert.equal(node.value.end.endpos, 46);
+            }
+        }));
+        assert(found, "AST_ObjectProperty not found");
+    });
+});