refactor: remove duplicated code

cmd/call.go

 package cmd
 
 import (
+	"encoding/json"
+	"github.com/phodal/coca/cmd/cmd_util"
 	"github.com/phodal/coca/config"
 	. "github.com/phodal/coca/core/domain/call_graph"
 	"github.com/phodal/coca/core/models"
 	. "github.com/phodal/coca/core/support"
-	"encoding/json"
 	"github.com/spf13/cobra"
 	"log"
-	"os/exec"
 	"strings"
 )
 
@@ -46,12 +46,7 @@ var callGraphCmd = &cobra.Command{
 			}
 
 			WriteToCocaFile("call.dot", content)
-
-			cmd := exec.Command("dot", []string{"-Tsvg", config.CocaConfig.ReporterPath + "/call.dot", "-o", config.CocaConfig.ReporterPath + "/call.svg"}...)
-			_, err := cmd.CombinedOutput()
-			if err != nil {
-				log.Fatalf("cmd.Run() failed with %s\n", err)
-			}
+			cmd_util.ConvertToSvg("call")
 		}
 	},
 }

cmd/rcall.go

 package cmd
 
 import (
+	"encoding/json"
+	"fmt"
+	"github.com/phodal/coca/cmd/cmd_util"
 	"github.com/phodal/coca/config"
 	"github.com/phodal/coca/core/domain/call_graph/rcall"
 	. "github.com/phodal/coca/core/support"
-	"encoding/json"
-	"fmt"
 	"github.com/spf13/cobra"
 	"log"
-	"os/exec"
 	"strings"
 )
 
@@ -51,12 +51,7 @@ var reverseCmd = &cobra.Command{
 		}
 
 		WriteToCocaFile("rcall.dot", content)
-
-		acmd := exec.Command("dot", []string{"-Tsvg", config.CocaConfig.ReporterPath + "/rcall.dot", "-o", config.CocaConfig.ReporterPath + "/rcall.svg"}...)
-		output, err := acmd.CombinedOutput()
-		if err != nil {
-			log.Fatalf("cmd.Run() failed with %s%s\n", err, string(output))
-		}
+		cmd_util.ConvertToSvg("call")
 	},
 }