ledgerutil exits with a proper code

This patch makes ledgerutil exit with a proper code when it fails.

Signed-off-by: Taku Shimosawa <taku.shimosawa.uf@hitachi.com>

cmd/ledgerutil/main.go

@@ -53,21 +53,22 @@ func main() {
 			*outputDir, err = os.Getwd()
 			if err != nil {
 				fmt.Printf("%s%s\n", compareErrorMessage, err)
-				return
+				os.Exit(1)
 			}
 		}
 
 		count, outputDirPath, err := ledgerutil.Compare(*snapshotPath1, *snapshotPath2, *outputDir, *firstDiffs)
 		if err != nil {
 			fmt.Printf("%s%s\n", compareErrorMessage, err)
-			return
+			os.Exit(1)
 		}
 
 		fmt.Print("\nSuccessfully compared snapshots. ")
 		if count == -1 {
 			fmt.Println("Both snapshot public state and private state hashes were the same. No results were generated.")
 		} else {
 			fmt.Printf("Results saved to %s. Total differences found: %d\n", outputDirPath, count)
+			os.Exit(2)
 		}
 	}
 }

cmd/ledgerutil/main_test.go

@@ -38,7 +38,11 @@ func TestArguments(t *testing.T) {
 		},
 		"one-snapshot": {
 			exitCode: 1,
-			args:     []string{"compare, snapshotDir1"},
+			args:     []string{"compare", "snapshotDir1"},
+		},
+		"invalid-snapshot-dirs": {
+			exitCode: 1,
+			args:     []string{"compare", "/non-existent/snapshot1", "/non-existent/snapshot2"},
 		},
 	}
 

docs/source/commands/ledgerutil.md

@@ -47,6 +47,14 @@ Args:
   <snapshotPath2>  Second ledger snapshot directory.
 ```
 
+## Exit Status
+
+### ledgerutil compare
+
+- `0` if the snapshots are identical
+- `2` if the snapshots are not identical
+- `1` if an error occurs
+
 ## Example Usage
 
 ### ledgerutil compare example

docs/wrappers/ledgerutil_postscript.md

@@ -1,3 +1,11 @@
+## Exit Status
+
+### ledgerutil compare
+
+- `0` if the snapshots are identical
+- `2` if the snapshots are not identical
+- `1` if an error occurs
+
 ## Example Usage
 
 ### ledgerutil compare example