diff --git a/src/cmd/go/internal/vcs/vcs.go b/src/cmd/go/internal/vcs/vcs.go
index 2e7b5b0bea4a6..1d10c7f6e95e4 100644
--- a/src/cmd/go/internal/vcs/vcs.go
+++ b/src/cmd/go/internal/vcs/vcs.go
@@ -37,6 +37,7 @@ import (
 type Cmd struct {
 	Name      string
 	Cmd       string     // name of binary to invoke command
+	Env       []string   // any environment values to set/override
 	RootNames []rootName // filename and mode indicating the root of a checkout directory
 
 	CreateCmd   []string // commands to download a fresh copy of a repository
@@ -154,6 +155,10 @@ func vcsByCmd(cmd string) *Cmd {
 var vcsHg = &Cmd{
 	Name: "Mercurial",
 	Cmd:  "hg",
+
+	// HGPLAIN=1 turns off additional output that a user may have enabled via
+	// config options or certain extensions.
+	Env: []string{"HGPLAIN=1"},
 	RootNames: []rootName{
 		{filename: ".hg", isDir: true},
 	},
@@ -189,12 +194,11 @@ func hgRemoteRepo(vcsHg *Cmd, rootDir string) (remoteRepo string, err error) {
 
 func hgStatus(vcsHg *Cmd, rootDir string) (Status, error) {
 	// Output changeset ID and seconds since epoch.
-	out, err := vcsHg.runOutputVerboseOnly(rootDir, `log -l1 -T {node}:{date|hgdate}`)
+	out, err := vcsHg.runOutputVerboseOnly(rootDir, `log -r. -T {node}:{date|hgdate}`)
 	if err != nil {
 		return Status{}, err
 	}
 
-	// Successful execution without output indicates an empty repo (no commits).
 	var rev string
 	var commitTime time.Time
 	if len(out) > 0 {
@@ -209,7 +213,7 @@ func hgStatus(vcsHg *Cmd, rootDir string) (Status, error) {
 	}
 
 	// Also look for untracked files.
-	out, err = vcsHg.runOutputVerboseOnly(rootDir, "status")
+	out, err = vcsHg.runOutputVerboseOnly(rootDir, "status -S")
 	if err != nil {
 		return Status{}, err
 	}
@@ -689,6 +693,9 @@ func (v *Cmd) run1(dir string, cmdline string, keyval []string, verbose bool) ([
 
 	cmd := exec.Command(v.Cmd, args...)
 	cmd.Dir = dir
+	if v.Env != nil {
+		cmd.Env = append(cmd.Environ(), v.Env...)
+	}
 	if cfg.BuildX {
 		fmt.Fprintf(os.Stderr, "cd %s\n", dir)
 		fmt.Fprintf(os.Stderr, "%s %s\n", v.Cmd, strings.Join(args, " "))
diff --git a/src/cmd/go/testdata/script/version_buildvcs_hg.txt b/src/cmd/go/testdata/script/version_buildvcs_hg.txt
index fbbd886102e1b..13904fae12db3 100644
--- a/src/cmd/go/testdata/script/version_buildvcs_hg.txt
+++ b/src/cmd/go/testdata/script/version_buildvcs_hg.txt
@@ -6,6 +6,8 @@
 [short] skip
 env GOBIN=$WORK/gopath/bin
 env oldpath=$PATH
+env TZ=GMT
+env HGRCPATH=$WORK/hgrc
 cd repo/a
 
 # If there's no local repository, there's no VCS info.
@@ -29,24 +31,43 @@ cd ..
 env PATH=$oldpath
 rm .hg
 
-# If there is an empty repository in a parent directory, only "uncommitted" is tagged.
+# An empty repository or one explicitly updated to null uses the null cset ID,
+# and the time is hard set to 1/1/70, regardless of the current time.
 exec hg init
 cd a
 go install
 go version -m $GOBIN/a$GOEXE
-! stdout vcs.revision
-! stdout vcs.time
+stdout '^\tbuild\tvcs.revision=0000000000000000000000000000000000000000$'
+stdout '^\tbuild\tvcs.time=1970-01-01T00:00:00Z$'
 stdout '^\tbuild\tvcs.modified=true$'
 cd ..
 
 # Revision and commit time are tagged for repositories with commits.
 exec hg add a README
-exec hg commit -m 'initial commit'
+exec hg commit -m 'initial commit' --user test-user --date '2024-07-31T01:21:27+00:00'
 cd a
 go install
 go version -m $GOBIN/a$GOEXE
-stdout '^\tbuild\tvcs.revision='
-stdout '^\tbuild\tvcs.time='
+stdout '^\tbuild\tvcs.revision=71eaed52daeaafea83cb604f75b0a0336ef2c345$'
+stdout '^\tbuild\tvcs.time=2024-07-31T01:21:27Z$'
+stdout '^\tbuild\tvcs.modified=false$'
+rm $GOBIN/a$GOEXE
+
+# Add an extra commit and then back off of it to show that the hash is
+# from the checked out revision, not the tip revision.
+cp ../../outside/empty.txt .
+exec hg ci -Am 'another commit' --user test-user --date '2024-08-01T19:24:38+00:00'
+exec hg update --clean -r '.^'
+
+# Modified state is not thrown off by extra status output
+exec hg bisect -v -g .
+exec hg bisect -v -b '.^^'
+exec hg status
+stdout '^.+'
+go install
+go version -m $GOBIN/a$GOEXE
+stdout '^\tbuild\tvcs.revision=71eaed52daeaafea83cb604f75b0a0336ef2c345$'
+stdout '^\tbuild\tvcs.time=2024-07-31T01:21:27Z$'
 stdout '^\tbuild\tvcs.modified=false$'
 rm $GOBIN/a$GOEXE
 
@@ -88,4 +109,10 @@ go 1.18
 package main
 
 func main() {}
+-- $WORK/hgrc --
+[ui]
+# tweakdefaults is an opt-in that may print extra output in commands like
+# status.  That can be disabled by setting HGPLAIN=1.
+tweakdefaults = 1
+
 -- outside/empty.txt --