Restrict config.show_banner to valid options (#15985)

crates/nu-protocol/src/config/mod.rs

@@ -17,7 +17,7 @@ pub use helper::extract_value;
 pub use history::{HistoryConfig, HistoryFileFormat};
 pub use hooks::Hooks;
 pub use ls::LsConfig;
-pub use output::ErrorStyle;
+pub use output::{BannerKind, ErrorStyle};
 pub use plugin_gc::{PluginGcConfig, PluginGcConfigs};
 pub use reedline::{CursorShapeConfig, EditBindings, NuCursorShape, ParsedKeybinding, ParsedMenu};
 pub use rm::RmConfig;
@@ -61,7 +61,7 @@ pub struct Config {
     pub rm: RmConfig,
     pub shell_integration: ShellIntegrationConfig,
     pub buffer_editor: Value,
-    pub show_banner: Value,
+    pub show_banner: BannerKind,
     pub bracketed_paste: bool,
     pub render_right_prompt_on_last_line: bool,
     pub explore: HashMap<String, Value>,
@@ -84,7 +84,7 @@ pub struct Config {
 impl Default for Config {
     fn default() -> Config {
         Config {
-            show_banner: Value::bool(true, Span::unknown()),
+            show_banner: BannerKind::default(),
 
             table: TableConfig::default(),
             rm: RmConfig::default(),

crates/nu-protocol/src/config/output.rs

@@ -25,3 +25,71 @@ impl UpdateFromValue for ErrorStyle {
         config_update_string_enum(self, value, path, errors)
     }
 }
+
+/// Option: show_banner
+#[derive(Clone, Copy, Debug, Default, PartialEq, Eq, Serialize, Deserialize)]
+pub enum BannerKind {
+    /// No banner on startup
+    None,
+    /// Abbreviated banner just containing the startup-time
+    Short,
+    /// The full banner including Ellie
+    #[default]
+    Full,
+}
+
+impl IntoValue for BannerKind {
+    fn into_value(self, span: Span) -> Value {
+        match self {
+            // This uses a custom implementation to reflect common config
+            // bool: true, false was used for a long time
+            // string: short was added later
+            BannerKind::None => Value::bool(false, span),
+            BannerKind::Short => Value::string("short", span),
+            BannerKind::Full => Value::bool(true, span),
+        }
+    }
+}
+
+impl UpdateFromValue for BannerKind {
+    fn update<'a>(
+        &mut self,
+        value: &'a Value,
+        path: &mut ConfigPath<'a>,
+        errors: &mut ConfigErrors,
+    ) {
+        match value {
+            Value::Bool { val, .. } => match val {
+                true => {
+                    *self = BannerKind::Full;
+                }
+                false => {
+                    *self = BannerKind::None;
+                }
+            },
+            Value::String { val, .. } => match val.as_str() {
+                "true" => {
+                    *self = BannerKind::Full;
+                }
+                "full" => {
+                    *self = BannerKind::Full;
+                }
+                "short" => {
+                    *self = BannerKind::Short;
+                }
+                "false" => {
+                    *self = BannerKind::None;
+                }
+                "none" => {
+                    *self = BannerKind::None;
+                }
+                _ => {
+                    errors.invalid_value(path, "true/'full', 'short', false/'none'", value);
+                }
+            },
+            _ => {
+                errors.invalid_value(path, "true/'full', 'short', false/'none'", value);
+            }
+        }
+    }
+}