fix: local builds are dev-<commit> again, not a Go pseudo-version (#68)

Go now stamps local builds with a module pseudo-version (v0.1.3-0.20261014174204-1c31a75d0507+dirty), so the version showed that instead of dev-<commit> as the docs say. The update check also took it for a pre-release of 0.1.3, a version that doesn't exist, rather than a development build. A pseudo-version is now dev-<its commit>, -dirty with uncommitted changes; real versions are unchanged.

Reviewed-on: #68
Co-authored-by: Karl-Einar Bergstrøm <karl-einarb@outlook.com>

cmd/lazysecrets/version.go

@@ -1,6 +1,10 @@
 package main
 
-import "runtime/debug"
+import (
+	"regexp"
+	"runtime/debug"
+	"strings"
+)
 
 // version is set by release builds:
 //
@@ -8,7 +12,12 @@ import "runtime/debug"
 var version string
 
 // versionString is the release version, or for other builds what Go
-// recorded: the module version (go install …@v1.2.3), else the commit.
+// recorded: the module version (go install …@v1.2.3), else the commit
+// (dev-c1a4f90, -dirty with changes not committed).
+// pseudo matches a Go pseudo-version (v0.1.3-0.20261014174204-1c31a75d0507,
+// maybe +dirty): its commit.
+var pseudo = regexp.MustCompile(`[-.]\d{14}-([0-9a-f]{12})(\+.*)?$`)
+
 func versionString() string {
 	if version != "" {
 		return version
@@ -18,6 +27,15 @@ func versionString() string {
 		return "dev"
 	}
 	if v := bi.Main.Version; v != "" && v != "(devel)" {
+		// A commit, not a release: a local build (Go stamps those too) or
+		// go install …@<commit>.
+		if m := pseudo.FindStringSubmatch(v); m != nil {
+			dirty := ""
+			if strings.HasSuffix(v, "+dirty") {
+				dirty = "-dirty"
+			}
+			return "dev-" + m[1][:7] + dirty
+		}
 		return v
 	}
 	var rev, dirty string

cmd/lazysecrets/version_test.go

@@ -0,0 +1,22 @@
+package main
+
+import "testing"
+
+func TestPseudoVersions(t *testing.T) {
+	for v, want := range map[string]string{
+		"v0.1.3-0.20261014174204-1c31a75d0507":       "1c31a75d0507",
+		"v0.1.3-0.20261014174204-1c31a75d0507+dirty": "1c31a75d0507",
+		"v0.0.0-20261014174204-1c31a75d0507":         "1c31a75d0507",
+		"v0.2.0-rc.1.0.20261014174204-1c31a75d0507":  "1c31a75d0507",
+		"v0.1.2":      "",
+		"v0.2.0-rc.1": "",
+	} {
+		got := ""
+		if m := pseudo.FindStringSubmatch(v); m != nil {
+			got = m[1]
+		}
+		if got != want {
+			t.Errorf("%s: %q, want %q", v, got, want)
+		}
+	}
+}