chore: Simplify logic in v1 command handler.

Author: hessjcg

cmd/cloud_sql_proxy/cloud_sql_proxy.go

@@ -764,7 +764,6 @@ type TranslationResult struct {
 	V2Args         []string
 	LogDebugStdout bool
 	Verbose        bool
-	Unsupported    []string
 	LegacySet      bool
 	V2Compat       bool
 	V2Mode         bool
@@ -804,18 +803,14 @@ func main() {
 	}
 
 	// Translation failed
-	if tr.V2Compat && len(tr.Unsupported) > 0 {
-		fmt.Fprintf(os.Stderr, "Error: -v2-compat flag is set, but the following flags are not supported in v2 compatibility mode: %s\n", strings.Join(tr.Unsupported, ", "))
+	if tr.V2Compat {
+		fmt.Fprintln(os.Stderr, "Error: -v2-compat flag is set, but translation to v2 failed.")
 		os.Exit(1)
 	}
 
 	fmt.Fprintln(os.Stderr, "This proxy is using Auth Proxy v1 legacy mode.")
 	if tr.LegacySet {
 		fmt.Fprintln(os.Stderr, "This proxy is using Auth Proxy v1 legacy mode because the -legacy-v1-proxy flag is set")
-	} else if len(tr.Unsupported) > 0 {
-		fmt.Fprintln(os.Stderr, "This proxy is using Auth Proxy v1 legacy mode because it is using")
-		fmt.Fprintln(os.Stderr, "flags that are not supported in v2 compatibility mode:")
-		fmt.Fprintln(os.Stderr, strings.Join(tr.Unsupported, ", "))
 	}
 
 	code := runProxy()
@@ -901,17 +896,6 @@ func translateV2Args() TranslationResult {
 		return tr
 	}
 
-	// Check for unsupported flags being set
-	fs.Visit(func(f *flag.Flag) {
-		switch f.Name {
-		case "check_region":
-			tr.Unsupported = append(tr.Unsupported, "-"+f.Name)
-		}
-	})
-	if len(tr.Unsupported) > 0 {
-		return tr
-	}
-
 	fs.Visit(func(f *flag.Flag) {
 		switch f.Name {
 		case "projects":
@@ -996,7 +980,6 @@ func translateV2Args() TranslationResult {
 				hasPrivate = true
 			default:
 				// Unknown type, fallback to v1
-				tr.Unsupported = append(tr.Unsupported, "-ip_address_types="+*ipAddressTypes)
 				return tr
 			}
 		}

cmd/cloud_sql_proxy/translation_test.go

@@ -124,9 +124,11 @@ func TestTranslateV2Args(t *testing.T) {
 			wantOk:      true,
 		},
 		{
-			name:   "unsupported flag check_region",
-			args:   []string{"cloud_sql_proxy", "-check_region", "-instances=i1"},
-			wantOk: false,
+			name:        "ignored flag check_region",
+			args:        []string{"cloud_sql_proxy", "-check_region", "-instances=i1"},
+			wantArgs:    []string{"--auto-ip", "i1"},
+			wantVerbose: true,
+			wantOk:      true,
 		},
 		{
 			name:     "fuse mode",

translatev2/translatev2_test.go

@@ -132,6 +132,11 @@ func TestModeComparison(t *testing.T) {
 			args:       []string{"-projects=my-project"},
 			v2Expected: true,
 		},
+		{
+			name:       "check_region flag stays in v2",
+			args:       []string{"-check_region", "-instances=p:r:i"},
+			v2Expected: true,
+		},
 	}
 
 	for _, tt := range tests {