// Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

library parser_test;

import 'package:polymer_expressions/parser.dart';
import 'package:polymer_expressions/expression.dart';
import 'package:unittest/unittest.dart';

expectParse(String s, Expression e) =>
    expect(new Parser(s).parse(), e, reason: s);

main() {

  group('parser', () {

    test('should parse an empty expression', () {
      expectParse('', empty());
    });

    test('should parse an identifier', () {
      expectParse('abc', ident('abc'));
    });

    test('should parse a string literal', () {
      expectParse('"abc"', literal('abc'));
    });

    test('should parse an integer literal', () {
      expectParse('123', literal(123));
    });

    test('should parse a double literal', () {
      expectParse('1.23', literal(1.23));
    });

    test('should parse a positive double literal', () {
      expectParse('+1.23', literal(1.23));
    });

    test('should parse a negative double literal', () {
      expectParse('-1.23', literal(-1.23));
    });

    test('should parse a plus operator with literals', () {
      expectParse('1 + 2', binary(literal(1), '+', literal(2)));
    });

    test('should parse binary operators', () {
      expectParse('a && b', binary(ident('a'), '&&', ident('b')));
      expectParse('1 && 2', binary(literal(1), '&&', literal(2)));
      expectParse('false && true', binary(literal(false), '&&', literal(true)));
      expectParse('false || true', binary(literal(false), '||', literal(true)));
    });

    test('should give multiply higher associativity than plus', () {
      expectParse('a + b * c',
          binary(
              ident('a'),
              '+',
              binary(ident('b'), '*', ident('c'))));
    });

    test('should give multiply higher associativity than plus 2', () {
      expectParse('a * b + c',
          binary(
              binary(ident('a'), '*', ident('b')),
              '+',
              ident('c')));
    });

    test('should parse a dot operator', () {
      expectParse('a.b', invoke(ident('a'), 'b'));
    });

    test('should parse chained dot operators', () {
      expectParse('a.b.c', invoke(invoke(ident('a'), 'b'), 'c'));
    });

    test('should give dot high associativity', () {
      expectParse('a * b.c', binary(ident('a'), '*', invoke(ident('b'), 'c')));
    });

    test('should parse a function with no arguments', () {
      expectParse('a()', invoke(ident('a'), null, []));
    });

    test('should parse a single function argument', () {
      expectParse('a(b)', invoke(ident('a'), null, [ident('b')]));
    });

    test('should parse a function call as a subexpression', () {
      expectParse('a() + 1',
          binary(
              invoke(ident('a'), null, []),
              '+',
              literal(1)));
    });

    test('should parse multiple function arguments', () {
      expectParse('a(b, c)',
          invoke(ident('a'), null, [ident('b'), ident('c')]));
    });

    test('should parse nested function calls', () {
      expectParse('a(b(c))', invoke(ident('a'), null, [
          invoke(ident('b'), null, [ident('c')])]));
    });

    test('should parse an empty method call', () {
      expectParse('a.b()', invoke(ident('a'), 'b', []));
    });

    test('should parse a method call with a single argument', () {
      expectParse('a.b(c)', invoke(ident('a'), 'b', [ident('c')]));
    });

    test('should parse a method call with multiple arguments', () {
      expectParse('a.b(c, d)',
          invoke(ident('a'), 'b', [ident('c'), ident('d')]));
    });

    test('should parse chained method calls', () {
      expectParse('a.b().c()', invoke(invoke(ident('a'), 'b', []), 'c', []));
    });

    test('should parse chained function calls', () {
      expectParse('a()()', invoke(invoke(ident('a'), null, []), null, []));
    });

    test('should parse parenthesized expression', () {
      expectParse('(a)', paren(ident('a')));
      expectParse('(( 3 * ((1 + 2)) ))', paren(paren(
          binary(literal(3), '*', paren(paren(
              binary(literal(1), '+', literal(2))))))));
    });

    test('should parse an index operator', () {
      expectParse('a[b]', invoke(ident('a'), '[]', [ident('b')]));
      expectParse('a.b[c]', invoke(invoke(ident('a'), 'b', null),
          '[]', [ident('c')]));
    });

    test('should parse chained index operators', () {
      expectParse('a[][]', invoke(invoke(ident('a'), '[]', []), '[]', []));
    });

    test('should parse multiple index operators', () {
      expectParse('a[b] + c[d]', binary(
          invoke(ident('a'), '[]', [ident('b')]),
          '+',
          invoke(ident('c'), '[]', [ident('d')])));
    });

    test('should parse a filter chain', () {
      expectParse('a | b | c', binary(binary(ident('a'), '|', ident('b')),
          '|', ident('c')));
    });

    test('should parse comprehension', () {
      expectParse('a in b', inExpr(ident('a'), ident('b')));
      expectParse('a in b.c',
          inExpr(ident('a'), invoke(ident('b'), 'c', null)));
      expectParse('a in b + c',
          inExpr(ident('a'), binary(ident('b'), '+', ident('c'))));
    });

    test('should reject comprehension with non-assignable left expression', () {
      expect(() => parse('a + 1 in b'), throwsException);
    });

    test('should reject keywords as identifiers', () {
      expect(() => parse('a.in'), throwsException);
    });

    test('should parse map literals', () {
      expectParse("{'a': 1}",
          mapLiteral([mapLiteralEntry(literal('a'), literal(1))]));
      expectParse("{'a': 1, 'b': 2 + 3}",
          mapLiteral([
              mapLiteralEntry(literal('a'), literal(1)),
              mapLiteralEntry(literal('b'),
                  binary(literal(2), '+', literal(3)))]));
      expectParse("{'a': foo()}",
          mapLiteral([mapLiteralEntry(
              literal('a'), invoke(ident('foo'), null, []))]));
      expectParse("{'a': foo('a')}",
          mapLiteral([mapLiteralEntry(
              literal('a'), invoke(ident('foo'), null, [literal('a')]))]));
    });

    test('should parse map literals with method calls', () {
      expectParse("{'a': 1}.length",
          invoke(mapLiteral([mapLiteralEntry(literal('a'), literal(1))]),
              'length'));
    });
  });
}