Speed up hasCommits check

hjwp · hjwp · commit c013c5857ad7 · 2025-06-27T12:46:20.000+01:00
`git rev-list --all` is very slow for large repositories
(order of 5s on a repo with 500k commits).

This alternative version works by checking whether HEAD points at a valid commit.
diff --git a/mob.go b/mob.go
@@ -297,8 +297,8 @@ func run(osArgs []string) {
 }
 
 func hasCommits() bool {
-	commitCount := silentgit("rev-list", "--all", "--count")
-	return commitCount != "0"
+	_, err := silentgitignorefailure("rev-parse", "--verify", "HEAD")
+	return (err == nil)
 }
 
 func currentCliName(argZero string) string {

Original file line number	Diff line number	Diff line change
`@@ -297,8 +297,8 @@ func run(osArgs []string) {`
`297`	`297`	`}`
`298`	`298`
`299`	`299`	`func hasCommits() bool {`
`300`		`- commitCount := silentgit("rev-list", "--all", "--count")`
`301`		`- return commitCount != "0"`
	`300`	`+ _, err := silentgitignorefailure("rev-parse", "--verify", "HEAD")`
	`301`	`+ return (err == nil)`
`302`	`302`	`}`
`303`	`303`
`304`	`304`	`func currentCliName(argZero string) string {`