758 lines
15 KiB
Go
758 lines
15 KiB
Go
package evaluator
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import (
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"errors"
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"monkey/lexer"
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"monkey/object"
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"monkey/parser"
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"os"
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"path/filepath"
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"testing"
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)
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func TestEvalIntegerExpression(t *testing.T) {
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tests := []struct {
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input string
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expected int64
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}{
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{"5", 5},
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{"10", 10},
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{"-5", -5},
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{"-10", -10},
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{"5 + 5 + 5 + 5 - 10", 10},
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{"2 * 2 * 2 * 2 * 2", 32},
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{"-50 + 100 + -50", 0},
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{"5 * 2 + 10", 20},
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{"5 + 2 * 10", 25},
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{"20 + 2 * -10", 0},
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{"50 / 2 * 2 + 10", 60},
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{"2 * (5 + 10)", 30},
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{"3 * 3 * 3 + 10", 37},
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{"3 * (3 * 3) + 10", 37},
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{"(5 + 10 * 2 + 15 / 3) * 2 + -10", 50},
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}
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for _, tt := range tests {
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evaluated := testEval(tt.input)
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testIntegerObject(t, evaluated, tt.expected)
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}
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}
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func TestEvalBooleanExpression(t *testing.T) {
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tests := []struct {
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input string
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expected bool
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}{
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{"true", true},
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{"false", false},
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{"1 < 2", true},
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{"1 > 2", false},
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{"1 < 1", false},
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{"1 > 1", false},
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{"1 == 1", true},
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{"1 != 1", false},
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{"1 == 2", false},
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{"1 != 2", true},
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{"true == true", true},
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{"false == false", true},
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{"true == false", false},
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{"true != false", true},
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{"false != true", true},
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{"(1 < 2) == true", true},
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{"(1 < 2) == false", false},
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{"(1 > 2) == true", false},
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{"(1 > 2) == false", true},
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{"(1 <= 2) == true", true},
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{"(1 <= 2) == false", false},
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{"(1 >= 2) == true", false},
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{"(1 >= 2) == false", true},
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{`"a" == "a"`, true},
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{`"a" < "b"`, true},
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{`"abc" == "abc"`, true},
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}
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for _, tt := range tests {
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evaluated := testEval(tt.input)
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testBooleanObject(t, evaluated, tt.expected)
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}
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}
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func TestBangOperator(t *testing.T) {
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tests := []struct {
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input string
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expected bool
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}{
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{"!true", false},
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{"!false", true},
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{"!5", false},
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{"!!true", true},
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{"!!false", false},
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{"!!5", true},
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}
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for _, tt := range tests {
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evaluated := testEval(tt.input)
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testBooleanObject(t, evaluated, tt.expected)
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}
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}
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func TestIfElseExpression(t *testing.T) {
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tests := []struct {
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input string
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expected interface{}
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}{
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{"if (true) { 10 }", 10},
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{"if (false) { 10 }", nil},
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{"if (1) { 10 }", 10},
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{"if (1 < 2) { 10 }", 10},
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{"if (1 > 2) { 10 }", nil},
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{"if (1 > 2) { 10 } else { 20 }", 20},
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{"if (1 < 2) { 10 } else { 20 }", 10},
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{"if (1 < 2) { 10 } else if (1 == 2) { 20 }", 10},
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{"if (1 > 2) { 10 } else if (1 == 2) { 20 } else { 30 }", 30},
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}
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for _, tt := range tests {
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evaluated := testEval(tt.input)
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integer, ok := tt.expected.(int)
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if ok {
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testIntegerObject(t, evaluated, int64(integer))
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} else {
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testNullObject(t, evaluated)
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}
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}
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}
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func TestReturnStatements(t *testing.T) {
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tests := []struct {
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input string
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expected int64
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}{
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{"return 10;", 10},
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{"return 10; 9;", 10},
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{"return 2 * 5; 9;", 10},
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{"9; return 2 * 5; 9;", 10},
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{"if (10 > 1) { return 10; }", 10},
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{
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`
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if (10 > 1) {
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if (10 > 1) {
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return 10;
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}
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return 1;
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}
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`,
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10,
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},
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{
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`
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let f = fn(x) {
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return x;
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x + 10;
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};
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f(10);`,
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10,
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},
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{
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`
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let f = fn(x) {
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let result = x + 10;
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return result;
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return 10;
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};
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f(10);`,
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20,
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},
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}
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for _, tt := range tests {
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evaluated := testEval(tt.input)
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testIntegerObject(t, evaluated, tt.expected)
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}
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}
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func TestErrorHandling(t *testing.T) {
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tests := []struct {
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input string
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expectedMessage string
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}{
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{
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"5 + true;",
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"type mismatch: INTEGER + BOOLEAN",
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},
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{
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"5 + true; 5;",
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"type mismatch: INTEGER + BOOLEAN",
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},
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{
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"-true",
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"unknown operator: -BOOLEAN",
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},
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{
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"true + false;",
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"unknown operator: BOOLEAN + BOOLEAN",
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},
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{
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"5; true + false; 5",
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"unknown operator: BOOLEAN + BOOLEAN",
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},
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{
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"if (10 > 1) { true + false; }",
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"unknown operator: BOOLEAN + BOOLEAN",
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},
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{
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`
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if (10 > 1) {
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if (10 > 1) {
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return true + false;
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}
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return 1;
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}
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`,
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"unknown operator: BOOLEAN + BOOLEAN",
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},
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{
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"foobar",
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"identifier not found: foobar",
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},
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{
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`"Hello" - "World"`,
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"unknown operator: STRING - STRING",
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},
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{
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`{"name": "Monkey"}[fn(x) { x }];`,
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"unusable as hash key: FUNCTION",
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},
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}
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for _, tt := range tests {
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evaluated := testEval(tt.input)
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errObj, ok := evaluated.(*object.Error)
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if !ok {
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t.Errorf("no error object returned. got=%T(%+v)",
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evaluated, evaluated)
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continue
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}
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if errObj.Message != tt.expectedMessage {
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t.Errorf("wrong error message. expected=%q, got=%q",
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tt.expectedMessage, errObj.Message)
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}
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}
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}
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func TestIndexAssignmentStatements(t *testing.T) {
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tests := []struct {
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input string
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expected int64
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}{
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{"let xs = [1, 2, 3]; xs[1] = 4; xs[1];", 4},
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}
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for _, tt := range tests {
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evaluated := testEval(tt.input)
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testIntegerObject(t, evaluated, tt.expected)
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}
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}
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func TestAssignmentStatements(t *testing.T) {
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tests := []struct {
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input string
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expected interface{}
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}{
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{"let a = 0; a = 5;", nil},
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{"let a = 0; a = 5; a;", 5},
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{"let a = 0; a = 5 * 5;", nil},
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{"let a = 0; a = 5 * 5; a;", 25},
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{"let a = 0; a = 5; let b = 0; b = a;", nil},
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{"let a = 0; a = 5; let b = 0; b = a; b;", 5},
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{"let a = 0; a = 5; let b = 0; b = a; let c = 0; c = a + b + 5;", nil},
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{"let a = 0; a = 5; let b = 0; b = a; let c = 0; c = a + b + 5; c;", 15},
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{"let a = 5; let b = a; a = 0;", nil},
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{"let a = 5; let b = a; a = 0; b;", 5},
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}
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for _, tt := range tests {
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evaluated := testEval(tt.input)
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integer, ok := tt.expected.(int)
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if ok {
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testIntegerObject(t, evaluated, int64(integer))
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} else {
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testNullObject(t, evaluated)
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}
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}
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}
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func TestLetStatements(t *testing.T) {
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tests := []struct {
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input string
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expected int64
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}{
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{"let a = 5; a;", 5},
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{"let a = 5 * 5; a;", 25},
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{"let a = 5; let b = a; b;", 5},
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{"let a = 5; let b = a; let c = a + b + 5; c;", 15},
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}
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for _, tt := range tests {
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testIntegerObject(t, testEval(tt.input), tt.expected)
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}
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}
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func TestFunctionObject(t *testing.T) {
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input := "fn(x) { x + 2; };"
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evaluated := testEval(input)
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fn, ok := evaluated.(*object.Function)
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if !ok {
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t.Fatalf("object is not Function. got=%T (%+v)", evaluated, evaluated)
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}
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if len(fn.Parameters) != 1 {
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t.Fatalf("function has wrong parameters. Parameters=%+v", fn.Parameters)
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}
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if fn.Parameters[0].String() != "x" {
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t.Fatalf("parameter is not 'x'. got=%q", fn.Parameters[0])
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}
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expectedBody := "(x + 2)"
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if fn.Body.String() != expectedBody {
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t.Fatalf("body is not %q. got=%q", expectedBody, fn.Body.String())
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}
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}
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func TestFunctionApplication(t *testing.T) {
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tests := []struct {
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input string
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expected int64
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}{
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{"let identity = fn(x) { x; }; identity(5);", 5},
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{"let identity = fn(x) { return x; }; identity(5);", 5},
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{"let double = fn(x) { x * 2; }; double(5);", 10},
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{"let add = fn(x, y) { x + y; }; add(5, 5);", 10},
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{"let add = fn(x, y) { x + y; }; add(5 + 5, add(5, 5));", 20},
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{"fn(x) { x; }(5)", 5},
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}
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for _, tt := range tests {
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testIntegerObject(t, testEval(tt.input), tt.expected)
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}
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}
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func TestClosures(t *testing.T) {
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input := `
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let newAdder = fn(x) {
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fn(y) { x + y };
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};
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let addTwo = newAdder(2);
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addTwo(2);`
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testIntegerObject(t, testEval(input), 4)
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}
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func TestStringLiteral(t *testing.T) {
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input := `"Hello World!"`
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evaluated := testEval(input)
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str, ok := evaluated.(*object.String)
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if !ok {
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t.Fatalf("object is not String. got=%T (+%v)", evaluated, evaluated)
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}
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if str.Value != "Hello World!" {
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t.Errorf("String has wrong value. got=%q", str.Value)
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}
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}
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func TestStringConcatenation(t *testing.T) {
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input := `"Hello" + " " + "World!"`
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evaluated := testEval(input)
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str, ok := evaluated.(*object.String)
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if !ok {
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t.Fatalf("object is not String. got=%T (+%v)", evaluated, evaluated)
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}
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if str.Value != "Hello World!" {
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t.Errorf("String has wrong value. got=%q", str.Value)
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}
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}
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func TestBuiltinFunctions(t *testing.T) {
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tests := []struct {
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input string
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expected interface{}
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}{
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{`len("")`, 0},
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{`len("four")`, 4},
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{`len("hello world")`, 11},
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{`len(1)`, errors.New("argument to `len` not supported, got INTEGER")},
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{`len("one", "two")`, errors.New("wrong number of arguments. got=2, want=1")},
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{`len("∑")`, 1},
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{`len([1, 2, 3])`, 3},
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{`len([])`, 0},
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{`first([1, 2, 3])`, 1},
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{`first([])`, nil},
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{`first(1)`, errors.New("argument to `first` must be ARRAY, got INTEGER")},
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{`last([1, 2, 3])`, 3},
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{`last([])`, nil},
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{`last(1)`, errors.New("argument to `last` must be ARRAY, got INTEGER")},
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{`rest([1, 2, 3])`, []int{2, 3}},
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{`rest([])`, nil},
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{`push([], 1)`, []int{1}},
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{`push(1, 1)`, errors.New("argument to `push` must be ARRAY, got INTEGER")},
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{`print("Hello World")`, nil},
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{`input()`, ""},
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{`pop([])`, errors.New("cannot pop from an empty array")},
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{`pop([1])`, 1},
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}
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for _, tt := range tests {
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evaluated := testEval(tt.input)
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switch expected := tt.expected.(type) {
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case int:
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testIntegerObject(t, evaluated, int64(expected))
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case string:
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testStringObject(t, evaluated, expected)
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case error:
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errObj, ok := evaluated.(*object.Error)
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if !ok {
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t.Errorf("object is not Error. got=%T (%+v)",
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evaluated, evaluated)
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continue
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}
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if errObj.Message != expected.Error() {
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t.Errorf("wrong error message. expected=%q, got=%q",
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expected, errObj.Message)
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}
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}
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}
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}
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func TestArrayLiterals(t *testing.T) {
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input := "[1, 2 * 2, 3 + 3]"
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evaluated := testEval(input)
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result, ok := evaluated.(*object.Array)
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if !ok {
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t.Fatalf("object is not Array. got=%T (+%v)", evaluated, evaluated)
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}
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if len(result.Elements) != 3 {
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t.Fatalf("array has wrong num of elements. got=%d", evaluated)
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}
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testIntegerObject(t, result.Elements[0], 1)
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testIntegerObject(t, result.Elements[1], 4)
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testIntegerObject(t, result.Elements[2], 6)
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}
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func TestArrayIndexExpressions(t *testing.T) {
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tests := []struct {
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input string
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expected interface{}
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}{
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{
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"[1, 2, 3][0]",
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1,
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},
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{
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"[1, 2, 3][1]",
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2,
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},
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{
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"[1, 2, 3][2]",
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3,
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},
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{
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"let i = 0; [1][i];",
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1,
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},
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{
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"[1, 2, 3][1 + 1];",
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3,
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},
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{
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"let myArray = [1, 2, 3]; myArray[2];",
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3,
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},
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{
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"let myArray = [1, 2, 3]; myArray[0] + myArray[1] + myArray[2];",
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6,
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},
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{
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"let myArray = [1, 2, 3]; let i = myArray[0]; myArray[i]",
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2,
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},
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{
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"[1, 2, 3][3]",
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nil,
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},
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{
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"[1, 2, 3][-1]",
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nil,
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},
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}
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for _, tt := range tests {
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evaluated := testEval(tt.input)
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integer, ok := tt.expected.(int)
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if ok {
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testIntegerObject(t, evaluated, int64(integer))
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} else {
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testNullObject(t, evaluated)
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}
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}
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}
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func TestHashLiterals(t *testing.T) {
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input := `let two = "two";
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{
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"one": 10 - 9,
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two: 1 + 1,
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"thr" + "ee": 6 / 2,
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4: 4,
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true: 5,
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false: 6
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}`
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evaluated := testEval(input)
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result, ok := evaluated.(*object.Hash)
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if !ok {
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t.Fatalf("Eval didn't return Hash. got=%T (%+v)", evaluated, evaluated)
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}
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expected := map[object.HashKey]int64{
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(&object.String{Value: "one"}).HashKey(): 1,
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(&object.String{Value: "two"}).HashKey(): 2,
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(&object.String{Value: "three"}).HashKey(): 3,
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(&object.Integer{Value: 4}).HashKey(): 4,
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TRUE.HashKey(): 5,
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FALSE.HashKey(): 6,
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}
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if len(result.Pairs) != len(expected) {
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t.Fatalf("Hash has wrong num of pair. got=%d", len(result.Pairs))
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}
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for expectedKey, expectedValue := range expected {
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pair, ok := result.Pairs[expectedKey]
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if !ok {
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t.Errorf("no pair for given key in Pairs")
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}
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testIntegerObject(t, pair.Value, expectedValue)
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}
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}
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func TestHashIndexExpressions(t *testing.T) {
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tests := []struct {
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input string
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expected interface{}
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}{
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{
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`{"foo": 5}["foo"]`,
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5,
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},
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{
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`{"foo": 5}["bar"]`,
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nil,
|
|
},
|
|
{
|
|
`let key = "foo"; {"foo": 5}[key]`,
|
|
5,
|
|
},
|
|
{
|
|
`{}["foo"]`,
|
|
nil,
|
|
},
|
|
{
|
|
`{5: 5}[5]`,
|
|
5,
|
|
},
|
|
{
|
|
`{true: 5}[true]`,
|
|
5,
|
|
},
|
|
{
|
|
`{false: 5}[false]`,
|
|
5,
|
|
},
|
|
}
|
|
|
|
for _, tt := range tests {
|
|
evaluated := testEval(tt.input)
|
|
|
|
integer, ok := tt.expected.(int)
|
|
if ok {
|
|
testIntegerObject(t, evaluated, int64(integer))
|
|
} else {
|
|
testNullObject(t, evaluated)
|
|
}
|
|
}
|
|
}
|
|
|
|
func TestWhileExpressions(t *testing.T) {
|
|
tests := []struct {
|
|
input string
|
|
expected interface{}
|
|
}{
|
|
{"while (false) { }", nil},
|
|
{"let n = 0; while (n < 10) { let n = n + 1 }; n", 10},
|
|
{"let n = 10; while (n > 0) { let n = n - 1 }; n", 0},
|
|
{"let n = 0; while (n < 10) { let n = n + 1 }", nil},
|
|
{"let n = 10; while (n > 0) { let n = n - 1 }", nil},
|
|
{"let n = 0; while (n < 10) { n = n + 1 }; n", 10},
|
|
{"let n = 10; while (n > 0) { n = n - 1 }; n", 0},
|
|
{"let n = 0; while (n < 10) { n = n + 1 }", nil},
|
|
{"let n = 10; while (n > 0) { n = n - 1 }", nil},
|
|
}
|
|
|
|
for _, tt := range tests {
|
|
evaluated := testEval(tt.input)
|
|
integer, ok := tt.expected.(int)
|
|
if ok {
|
|
testIntegerObject(t, evaluated, int64(integer))
|
|
} else {
|
|
testNullObject(t, evaluated)
|
|
}
|
|
}
|
|
}
|
|
|
|
func testEval(input string) object.Object {
|
|
l := lexer.New(input)
|
|
p := parser.New(l)
|
|
program := p.ParseProgram()
|
|
env := object.NewEnvironment()
|
|
|
|
return Eval(program, env)
|
|
}
|
|
|
|
func testIntegerObject(t *testing.T, obj object.Object, expected int64) bool {
|
|
result, ok := obj.(*object.Integer)
|
|
if !ok {
|
|
t.Errorf("object is not Integer. got=%T (%+v)", obj, obj)
|
|
return false
|
|
}
|
|
if result.Value != expected {
|
|
t.Errorf("object has wrong value. got=%d, want=%d", result.Value, expected)
|
|
return false
|
|
}
|
|
|
|
return true
|
|
}
|
|
|
|
func TestNullExpression(t *testing.T) {
|
|
evaluated := testEval("null")
|
|
testNullObject(t, evaluated)
|
|
}
|
|
|
|
func testBooleanObject(t *testing.T, obj object.Object, expected bool) bool {
|
|
result, ok := obj.(*object.Boolean)
|
|
if !ok {
|
|
t.Errorf("object is not Boolean. got=%T (%+v)", obj, obj)
|
|
return false
|
|
}
|
|
if result.Value != expected {
|
|
t.Errorf("object has wrong value. got=%t, want=%t", result.Value, expected)
|
|
return false
|
|
}
|
|
|
|
return true
|
|
}
|
|
|
|
func testNullObject(t *testing.T, obj object.Object) bool {
|
|
if obj != NULL {
|
|
t.Errorf("object is not NULL. got=%T (%+v)", obj, obj)
|
|
return false
|
|
}
|
|
return true
|
|
}
|
|
|
|
func testStringObject(t *testing.T, obj object.Object, expected string) bool {
|
|
result, ok := obj.(*object.String)
|
|
if !ok {
|
|
t.Errorf("object is not String. got=%T (%+v)", obj, obj)
|
|
return false
|
|
}
|
|
if result.Value != expected {
|
|
t.Errorf("object has wrong value. got=%s, want=%s",
|
|
result.Value, expected)
|
|
return false
|
|
}
|
|
return true
|
|
}
|
|
|
|
func TestExamples(t *testing.T) {
|
|
matches, err := filepath.Glob("../examples/*.monkey")
|
|
if err != nil {
|
|
t.Error(err)
|
|
}
|
|
|
|
for _, match := range matches {
|
|
b, err := os.ReadFile(match)
|
|
if err != nil {
|
|
t.Error(err)
|
|
}
|
|
testEval(string(b))
|
|
}
|
|
}
|
|
|
|
func TestStringIndexExpressions(t *testing.T) {
|
|
tests := []struct {
|
|
input string
|
|
expected interface{}
|
|
}{
|
|
{
|
|
`"abc"[0]`,
|
|
"a",
|
|
},
|
|
{
|
|
`"abc"[1]`,
|
|
"b",
|
|
},
|
|
{
|
|
`"abc"[2]`,
|
|
"c",
|
|
},
|
|
{
|
|
`let i = 0; "abc"[i];`,
|
|
"a",
|
|
},
|
|
{
|
|
`"abc"[1 + 1];`,
|
|
"c",
|
|
},
|
|
{
|
|
`let myString = "abc"; myString[0] + myString[1] + myString[2];`,
|
|
"abc",
|
|
},
|
|
{
|
|
`"abc"[3]`,
|
|
"",
|
|
},
|
|
{
|
|
`"foo"[-1]`,
|
|
"",
|
|
},
|
|
}
|
|
|
|
for _, tt := range tests {
|
|
evaluated := testEval(tt.input)
|
|
str, ok := tt.expected.(string)
|
|
if ok {
|
|
testStringObject(t, evaluated, string(str))
|
|
} else {
|
|
testNullObject(t, evaluated)
|
|
}
|
|
}
|
|
}
|