fix(babel-plugin): apply the right context for string static methods (#615)

* fix(babel-plugin): apply the right context for string static methods

* chore: format code

Author: nonzzz

packages/babel-plugin/__tests__/evaluation/stylex-evaluation-test.js

@@ -229,5 +229,17 @@ describe('custom path evaluation works as expected', () => {
         c: 4,
       });
     });
+
+    test('Methods called by string should be bind', () => {
+      expect(
+        evaluateFirstStatement(
+          'const x = "".concat("10px"," ").concat("10px");',
+          {},
+        ),
+      ).toBe('10px 10px');
+      expect(evaluateFirstStatement('const x = "abc".charCodeAt(0);', {})).toBe(
+        97,
+      );
+    });
   });
 });

packages/babel-plugin/src/utils/evaluate-path.js

@@ -692,6 +692,9 @@ function _evaluate(path: NodePath<>, state: State): any {
       ) {
         const val: number | string = object.node.value;
         func = (val as $FlowFixMe)[property.node.name];
+        if (typeof val === 'string') {
+          context = object.node.value;
+        }
       }
 
       if (func == null) {