chore: embed version in test too (#1926)

This change is a simple resolution to a build configuration error in google3.

Also, fix two docstring lints.

proxy/util/cloudsqlutil.go

@@ -56,7 +56,7 @@ var versionString string
 // metadataString indicates additional build or distribution metadata.
 var metadataString = ""
 
-// semanticVersion returns the version of the proxy in a semver format.
+// SemanticVersion returns the version of the proxy in a semver format.
 func SemanticVersion() string {
 	v := strings.TrimSpace(versionString)
 	if metadataString != "" {
@@ -65,7 +65,7 @@ func SemanticVersion() string {
 	return v
 }
 
-// userAgentFromVersionString returns an appropriate user agent string
+// UserAgentFromVersionString returns an appropriate user agent string
 // for identifying this proxy process.
 func UserAgentFromVersionString() string {
 	return "cloud_sql_proxy/" + SemanticVersion()

proxy/util/cloudsqlutil_test.go

@@ -15,29 +15,24 @@
 package util
 
 import (
-	"os"
+	_ "embed"
 	"strings"
 	"testing"
 )
 
+//go:embed version.txt
+var actualVersion string
+
 func TestSemanticVersion(t *testing.T) {
-	v, err := os.ReadFile("version.txt")
-	if err != nil {
-		t.Fatalf("failed to read version.txt: %v", err)
-	}
-	want := strings.TrimSpace(string(v))
+	want := strings.TrimSpace(actualVersion)
 
 	if got := SemanticVersion(); got != want {
 		t.Fatalf("want = %q, got = %q", want, got)
 	}
 }
 
 func TestUserAgentFromVersionString(t *testing.T) {
-	v, err := os.ReadFile("version.txt")
-	if err != nil {
-		t.Fatalf("failed to read version.txt: %v", err)
-	}
-	want := "cloud_sql_proxy/" + strings.TrimSpace(string(v))
+	want := "cloud_sql_proxy/" + strings.TrimSpace(actualVersion)
 
 	if got := UserAgentFromVersionString(); got != want {
 		t.Fatalf("want = %q, got = %q", want, got)