@Test
	public void testLeftRecursionWithMultiplePrimaryAndRecursiveOps() throws Exception {
		LexerGrammar lg = new LexerGrammar(lexerText);
		Grammar g = new Grammar(
			"parser grammar T;\n" +
			"s : e EOF ;\n" +
			"e : e MULT e\n" +
			"  | e PLUS e\n" +
			"  | INT\n" +
			"  | ID\n" +
			"  ;\n",
			lg);

		testInterp(lg, g, "s", "a",		"(s:1 (e:4 a) <EOF>)");
		testInterp(lg, g, "e", "a",		"(e:4 a)");
		testInterp(lg, g, "e", "34",	"(e:3 34)");
		testInterp(lg, g, "e", "a+1",	"(e:2 (e:4 a) + (e:3 1))");
		testInterp(lg, g, "e", "1+2*a",	"(e:2 (e:3 1) + (e:1 (e:3 2) * (e:4 a)))");
	}
Tests to ensure GrammarParserInterpreter subclass of ParserInterpreter
 hasn't messed anything up.
tool-testsuite/test/org/antlr/v4/test/tool/TestGrammarParserInterpreter.java