only print themes hint in interactive mode

CHANGELOG.md

@@ -5,6 +5,8 @@
 
 ## Bugfixes
 
+- only print themes hint in interactive mode (`bat --list-themes`), see #1439 (@rsteube)
+
 ## Other
 
 ## Syntaxes

src/bin/bat/main.rs

@@ -200,11 +200,6 @@ pub fn list_themes(cfg: &Config) -> Result<()> {
                 .ok();
             writeln!(stdout)?;
         }
-    } else {
-        for theme in assets.themes() {
-            writeln!(stdout, "{}", theme)?;
-        }
-    }
         writeln!(
             stdout,
             "Further themes can be installed to '{}', \
@@ -213,6 +208,11 @@ pub fn list_themes(cfg: &Config) -> Result<()> {
             https://github.com/sharkdp/bat#adding-new-themes",
             config_file().join("themes").to_string_lossy()
         )?;
+    } else {
+        for theme in assets.themes() {
+            writeln!(stdout, "{}", theme)?;
+        }
+    }
 
     Ok(())
 }