🧪 [testing improvement] Add integration tests for tsc lint --fix

cli/src/commands/lint.rs

@@ -70,7 +70,7 @@ pub fn execute(path_str: Option<&str>, fix: bool) -> ExitCode {
                     }
                 }
 
-                // Fix deprecation warnings
+                // If --fix is enabled, automatically modernize deprecated keywords and constructs
                 if fix {
                     let migrated = migrate_source(&content);
                     if migrated != content {

cli/tests/cli_tests.rs

@@ -43,3 +43,30 @@ fn test_cli_emit_commands() {
         _ => panic!("Expected EmitLlvm subcommand"),
     }
 }
+
+#[test]
+fn test_cli_lint_fix() {
+    let args = vec!["tech", "lint", "src/main.txs", "--fix"];
+    let cli = Cli::try_parse_from(args).expect("args parse successfully");
+    match cli.command {
+        Commands::Lint { path, fix } => {
+            assert_eq!(path.as_deref(), Some("src/main.txs"));
+            assert!(fix);
+        }
+        _ => panic!("Expected Lint subcommand"),
+    }
+
+    // Verify actual lint execute with --fix on a temporary file with deprecated syntax
+    let temp_dir = std::env::temp_dir().join("techscript_lint_test");
+    let _ = std::fs::create_dir_all(&temp_dir);
+    let test_file = temp_dir.join("deprecated.txs");
+    std::fs::write(&test_file, "let x = 10;").expect("write test file");
+
+    let status = techscript_cli::commands::lint::execute(Some(test_file.to_str().unwrap()), true);
+    assert_eq!(status, techscript_cli::exit_code::ExitCode::Success);
+
+    let content = std::fs::read_to_string(&test_file).expect("read test file");
+    assert_eq!(content, "x = 10");
+
+    let _ = std::fs::remove_dir_all(&temp_dir);
+}