feat(arg): add into_info conversion and flag formatting helpers

- Move PickerArg-to-PickerArgInfo conversion into an `into_info` method
- Add `short_flag()` and `long_flag()` methods to PickerArgInfo

2 files changed, 82 insertions, 24 deletions

diff --git a/arg_picker/src/arg.rs b/arg_picker/src/arg.rs
index a352418..4fa21b5 100644
--- a/arg_picker/src/arg.rs
+++ b/arg_picker/src/arg.rs
@@ -1,4 +1,4 @@
-use crate::Pickable;
+use crate::{Pickable, PickerArgInfo};
 use std::marker::PhantomData;
 
 /// Represents a constraint definition for a parameter selection.
@@ -133,6 +133,35 @@ where
         self.positional = positional;
         self
     }
+
+    /// Converts this `PickerArg` into a `PickerArgInfo` value.
+    ///
+    /// This is a convenience method equivalent to calling `PickerArgInfo::from(self)`.
+    pub fn into_info(self) -> PickerArgInfo<'a> {
+        let value = self;
+        let (long, alias) = match value.full.len() {
+            0 => (None, None),
+            _ => {
+                let long = Some(value.full[0]);
+                let alias = if value.full.len() > 1 {
+                    Some(value.full[1..].to_vec())
+                } else {
+                    None
+                };
+                (long, alias)
+            }
+        };
+
+        PickerArgInfo {
+            short: value.short,
+            long,
+            alias,
+            positional: value.positional,
+            optional: false,
+            multi: false,
+            is_flag: false,
+        }
+    }
 }
 
 /// Describes the attribute (behavior) of a command-line parameter.
diff --git a/arg_picker/src/infos.rs b/arg_picker/src/infos.rs
index 074539a..c17b6a2 100644
--- a/arg_picker/src/infos.rs
+++ b/arg_picker/src/infos.rs
@@ -1,4 +1,4 @@
-use crate::{Pickable, PickerArg};
+use crate::{Pickable, PickerArg, parselib::ParserStyle};
 
 /// Represents the result of parsing or looking up a value.
 ///
@@ -288,28 +288,7 @@ where
     T: Pickable<'a>,
 {
     fn from(value: PickerArg<'a, T>) -> Self {
-        let (long, alias) = match value.full.len() {
-            0 => (None, None),
-            _ => {
-                let long = Some(value.full[0]);
-                let alias = if value.full.len() > 1 {
-                    Some(value.full[1..].to_vec())
-                } else {
-                    None
-                };
-                (long, alias)
-            }
-        };
-
-        Self {
-            short: value.short,
-            long,
-            alias,
-            positional: value.positional,
-            optional: false,
-            multi: false,
-            is_flag: false,
-        }
+        value.into_info()
     }
 }
 
@@ -437,6 +416,56 @@ impl<'a> PickerArgInfo<'a> {
         self.is_flag = is_flag;
         self
     }
+
+    /// Returns the short flag string, e.g. `-n` for short `n`.
+    ///
+    /// Uses [`ParserStyle::global_style()`] to format the flag.
+    ///
+    /// # Returns
+    ///
+    /// - `Some(String)` if `self.short` is set.
+    /// - `None` if `self.short` is `None`.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use arg_picker::PickerArgInfo;
+    ///
+    /// let info = PickerArgInfo::new().with_short('n');
+    /// assert_eq!(info.short_flag(), Some("-n".to_string()));
+    ///
+    /// let info = PickerArgInfo::new();
+    /// assert_eq!(info.short_flag(), None);
+    /// ```
+    pub fn short_flag(&self) -> Option<String> {
+        let short = self.short?;
+        Some(ParserStyle::global_style().flag_string(short))
+    }
+
+    /// Returns the long flag string, e.g. `--name` for long `"name"`.
+    ///
+    /// Uses [`ParserStyle::global_style()`] to format the flag.
+    ///
+    /// # Returns
+    ///
+    /// - `Some(String)` if `self.long` is set.
+    /// - `None` if `self.long` is `None`.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use arg_picker::PickerArgInfo;
+    ///
+    /// let info = PickerArgInfo::new().with_long("name");
+    /// assert_eq!(info.long_flag(), Some("--name".to_string()));
+    ///
+    /// let info = PickerArgInfo::new();
+    /// assert_eq!(info.long_flag(), None);
+    /// ```
+    pub fn long_flag(&self) -> Option<String> {
+        let long = self.long?;
+        Some(ParserStyle::global_style().flag_string(long))
+    }
 }
 
 impl<'a> Default for PickerArgInfo<'a> {