Initial support for interactive mode #14

For now, there is a possible bug with goline, we will talk about it
before merge it to develop.

cmd.go

@@ -8,7 +8,6 @@ import (
 )
 
 var path *string
-var query string
 
 func init() {
     parseCommandLine()
@@ -42,13 +41,14 @@ func printTables() {
 func parseCommandLine() {
     path = flag.String("p", ".", "The (optional) path to run gitql")
     version := flag.Bool("v", false, "The version of gitql")
+    interactive = flag.Bool("i", false, "Enter to interactive mode")
     showTables := flag.Bool("show-tables", false, "Show all tables")
     flag.Usage = usage
     flag.Parse()
 
     if *version {
         // @todo refactor to dynamic value
-        fmt.Println("Gitql 1.0.0")
+        fmt.Println("Gitql 1.0.1")
         os.Exit(0)
     }
 
@@ -59,7 +59,7 @@ func parseCommandLine() {
     }
 
     query = flag.Arg(0)
-    if flag.NArg() != 1 {
+    if !*interactive && flag.NArg() != 1 {
         flag.Usage()
         os.Exit(1)
     }

gitql.go

@@ -4,17 +4,44 @@ import (
 	"github.com/cloudson/gitql/parser"
 	"github.com/cloudson/gitql/runtime"
 	"github.com/cloudson/gitql/semantical"
+	"github.com/nemith/goline"
 	"log"
 	"path/filepath"
 )
 
+// global vars set in init() function 
+var query string
+var interactive *bool
+
 func main() {
 	folder, errFile := filepath.Abs(*path)
 
 	if errFile != nil {
 		log.Fatalln(errFile)
 	}
 
+	if !*interactive {
+		runQuery(query, folder)
+		return 
+	}
+
+	gl := goline.NewGoLine(goline.StringPrompt("gitql> "))
+	for {
+		data, err := gl.Line()
+		if err != nil {
+        	if err != goline.UserTerminatedError {
+        		log.Fatalln(err)
+        	}
+        }
+
+		if err == goline.UserTerminatedError || data == "exit" || data == "quit" {
+            return
+        }
+        runQuery(data, folder)
+	}
+}
+
+func runQuery(query, folder string) {
 	parser.New(query)
 	ast, errGit := parser.AST()
 	if errGit != nil {

runtime/runtime.go

@@ -228,6 +228,7 @@ func printTable(rows []tableRow, fields []string) {
 	for _, r := range rows {
 		table.AddRow(r)
 	}
+	fmt.Println()
 	table.Print()
 }
 
@@ -322,8 +323,9 @@ func metadataReference(identifier string, object *git.Reference) string {
 		if object.IsTag() {
 			return REFERENCE_TYPE_TAG
 		}
+		log.Fatalf("Unexcpeted object %s\n", object.Name())
 	}
-	log.Fatalf("Field %s not implemented yet\n", identifier)
+	log.Fatalf("Field '%s' not implemented yet\n", identifier)
 
 	return ""
 }