Compiler update (#21)

* added seperate folders for cmd packages.

* Fix netmodes in test + reverse bigint bytes

* glide get deps

* add, sub, mul, div

* booleans

* strings

* binary expressions

* if statements

* function calls

* composite literals (slice, array)

* Added lots of test cases and update readme.

pkg/vm/compiler/tests/compiler_test.go

@@ -0,0 +1,65 @@
+package compiler_test
+
+import (
+	"bytes"
+	"encoding/hex"
+	"fmt"
+	"os"
+	"strings"
+	"testing"
+	"text/tabwriter"
+
+	"github.com/CityOfZion/neo-go/pkg/vm"
+	"github.com/CityOfZion/neo-go/pkg/vm/compiler"
+)
+
+type testCase struct {
+	name   string
+	src    string
+	result string
+}
+
+func TestAllCases(t *testing.T) {
+	testCases := []testCase{}
+	testCases = append(testCases, stringTestCases...)
+	testCases = append(testCases, binaryExprTestCases...)
+	testCases = append(testCases, ifStatementTestCases...)
+	testCases = append(testCases, functionCallTestCases...)
+
+	for _, tc := range testCases {
+		c := compiler.New()
+		if err := c.Compile(strings.NewReader(tc.src)); err != nil {
+			t.Fatal(err)
+		}
+
+		expectedResult, err := hex.DecodeString(tc.result)
+		if err != nil {
+			t.Fatal(err)
+		}
+
+		if bytes.Compare(c.Buffer().Bytes(), expectedResult) != 0 {
+			t.Log(hex.EncodeToString(c.Buffer().Bytes()))
+			want, _ := hex.DecodeString(tc.result)
+			dumpOpCodeSideBySide(c.Buffer().Bytes(), want)
+			t.Fatalf("compiling %s failed", tc.name)
+		}
+	}
+}
+
+func dumpOpCodeSideBySide(have, want []byte) {
+	w := tabwriter.NewWriter(os.Stdout, 0, 0, 4, ' ', 0)
+	fmt.Fprintln(w, "INDEX\tHAVE OPCODE\tDESC\tWANT OPCODE\tDESC\tDIFF")
+
+	for i := 0; i < len(have); i++ {
+		if len(want) <= i {
+			break
+		}
+		diff := ""
+		if have[i] != want[i] {
+			diff = "<<"
+		}
+		fmt.Fprintf(w, "%d\t0x%2x\t%s\t0x%2x\t%s\t%s\n",
+			i, have[i], vm.OpCode(have[i]), want[i], vm.OpCode(want[i]), diff)
+	}
+	w.Flush()
+}