aboutsummaryrefslogtreecommitdiff
path: root/lexer/lexer_test.go
blob: 0a7f248ee1a2103a650bf6ae23ffd51d663bbfed (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
package lexer

import (
	"testing"

	"monkey/token"
)

func TestNextToken(t *testing.T) {
	input := `let five = 5;
let ten = 10;

let add = fn(x, y) {
  x + y;
};

let result = add(five, ten);
!-/*5;
5 < 10 > 5;

if (5 < 10) {
	return true;
} else {
	return false;
}

10 == 10;
10 != 9;
`

	tests := []struct {
		expectedType    token.TokenType
		expectedLiteral string
	}{
		{token.LET, "let"},
		{token.IDENT, "five"},
		{token.ASSIGN, "="},
		{token.INT, "5"},
		{token.SEMICOLON, ";"},
		{token.LET, "let"},
		{token.IDENT, "ten"},
		{token.ASSIGN, "="},
		{token.INT, "10"},
		{token.SEMICOLON, ";"},
		{token.LET, "let"},
		{token.IDENT, "add"},
		{token.ASSIGN, "="},
		{token.FUNCTION, "fn"},
		{token.LPAREN, "("},
		{token.IDENT, "x"},
		{token.COMMA, ","},
		{token.IDENT, "y"},
		{token.RPAREN, ")"},
		{token.LBRACE, "{"},
		{token.IDENT, "x"},
		{token.PLUS, "+"},
		{token.IDENT, "y"},
		{token.SEMICOLON, ";"},
		{token.RBRACE, "}"},
		{token.SEMICOLON, ";"},
		{token.LET, "let"},
		{token.IDENT, "result"},
		{token.ASSIGN, "="},
		{token.IDENT, "add"},
		{token.LPAREN, "("},
		{token.IDENT, "five"},
		{token.COMMA, ","},
		{token.IDENT, "ten"},
		{token.RPAREN, ")"},
		{token.SEMICOLON, ";"},
		{token.BANG, "!"},
		{token.MINUS, "-"},
		{token.SLASH, "/"},
		{token.ASTERISK, "*"},
		{token.INT, "5"},
		{token.SEMICOLON, ";"},
		{token.INT, "5"},
		{token.LT, "<"},
		{token.INT, "10"},
		{token.GT, ">"},
		{token.INT, "5"},
		{token.SEMICOLON, ";"},
		{token.IF, "if"},
		{token.LPAREN, "("},
		{token.INT, "5"},
		{token.LT, "<"},
		{token.INT, "10"},
		{token.RPAREN, ")"},
		{token.LBRACE, "{"},
		{token.RETURN, "return"},
		{token.TRUE, "true"},
		{token.SEMICOLON, ";"},
		{token.RBRACE, "}"},
		{token.ELSE, "else"},
		{token.LBRACE, "{"},
		{token.RETURN, "return"},
		{token.FALSE, "false"},
		{token.SEMICOLON, ";"},
		{token.RBRACE, "}"},
		{token.INT, "10"},
		{token.EQ, "=="},
		{token.INT, "10"},
		{token.SEMICOLON, ";"},
		{token.INT, "10"},
		{token.NOT_EQ, "!="},
		{token.INT, "9"},
		{token.SEMICOLON, ";"},
		{token.EOF, ""},
	}

	l := New(input)

	for i, tt := range tests {
		tok := l.NextToken()

		if tok.Type != tt.expectedType {
			t.Fatalf("tests[%d] - tokentype wrong. expected=%q, got=%q",
				i, tt.expectedType, tok.Type)
		}

		if tok.Literal != tt.expectedLiteral {
			t.Fatalf("tests[%d] - literal wrong. expected=%q, got=%q",
				i, tt.expectedLiteral, tok.Literal)
		}
	}
}