Move Value to helpers, separate span call (#10121)

# Description

As part of the refactor to split spans off of Value, this moves to using
helper functions to create values, and using `.span()` instead of
matching span out of Value directly.

Hoping to get a few more helping hands to finish this, as there are a
lot of commands to update :)

# User-Facing Changes
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---------

Co-authored-by: Darren Schroeder <343840+fdncred@users.noreply.github.com>
Co-authored-by: WindSoilder <windsoilder@outlook.com>

crates/nu_plugin_custom_values/src/cool_custom_value.rs

@@ -14,22 +14,20 @@ impl CoolCustomValue {
     }
 
     pub fn into_value(self, span: Span) -> Value {
-        Value::CustomValue {
-            val: Box::new(self),
-            span,
-        }
+        Value::custom_value(Box::new(self), span)
     }
 
     pub fn try_from_value(value: &Value) -> Result<Self, ShellError> {
+        let span = value.span();
         match value {
-            Value::CustomValue { val, span } => {
+            Value::CustomValue { val, .. } => {
                 if let Some(cool) = val.as_any().downcast_ref::<Self>() {
                     Ok(cool.clone())
                 } else {
                     Err(ShellError::CantConvert {
                         to_type: "cool".into(),
                         from_type: "non-cool".into(),
-                        span: *span,
+                        span,
                         help: None,
                     })
                 }
@@ -37,7 +35,7 @@ impl CoolCustomValue {
             x => Err(ShellError::CantConvert {
                 to_type: "cool".into(),
                 from_type: x.get_type().to_string(),
-                span: x.span(),
+                span,
                 help: None,
             }),
         }
@@ -47,10 +45,7 @@ impl CoolCustomValue {
 #[typetag::serde]
 impl CustomValue for CoolCustomValue {
     fn clone_value(&self, span: nu_protocol::Span) -> Value {
-        Value::CustomValue {
-            val: Box::new(self.clone()),
-            span,
-        }
+        Value::custom_value(Box::new(self.clone()), span)
     }
 
     fn value_string(&self) -> String {
@@ -58,10 +53,10 @@ impl CustomValue for CoolCustomValue {
     }
 
     fn to_base_value(&self, span: nu_protocol::Span) -> Result<Value, ShellError> {
-        Ok(Value::String {
-            val: format!("I used to be a custom value! My data was ({})", self.cool),
+        Ok(Value::string(
+            format!("I used to be a custom value! My data was ({})", self.cool),
             span,
-        })
+        ))
     }
 
     fn as_any(&self) -> &dyn std::any::Any {

crates/nu_plugin_custom_values/src/second_custom_value.rs

@@ -14,27 +14,25 @@ impl SecondCustomValue {
     }
 
     pub fn into_value(self, span: Span) -> Value {
-        Value::CustomValue {
-            val: Box::new(self),
-            span,
-        }
+        Value::custom_value(Box::new(self), span)
     }
 
     pub fn try_from_value(value: &Value) -> Result<Self, ShellError> {
+        let span = value.span();
         match value {
-            Value::CustomValue { val, span } => match val.as_any().downcast_ref::<Self>() {
+            Value::CustomValue { val, .. } => match val.as_any().downcast_ref::<Self>() {
                 Some(value) => Ok(value.clone()),
                 None => Err(ShellError::CantConvert {
                     to_type: "cool".into(),
                     from_type: "non-cool".into(),
-                    span: *span,
+                    span,
                     help: None,
                 }),
             },
             x => Err(ShellError::CantConvert {
                 to_type: "cool".into(),
                 from_type: x.get_type().to_string(),
-                span: x.span(),
+                span,
                 help: None,
             }),
         }
@@ -44,10 +42,7 @@ impl SecondCustomValue {
 #[typetag::serde]
 impl CustomValue for SecondCustomValue {
     fn clone_value(&self, span: nu_protocol::Span) -> Value {
-        Value::CustomValue {
-            val: Box::new(self.clone()),
-            span,
-        }
+        Value::custom_value(Box::new(self.clone()), span)
     }
 
     fn value_string(&self) -> String {
@@ -55,13 +50,13 @@ impl CustomValue for SecondCustomValue {
     }
 
     fn to_base_value(&self, span: nu_protocol::Span) -> Result<Value, ShellError> {
-        Ok(Value::String {
-            val: format!(
+        Ok(Value::string(
+            format!(
                 "I used to be a DIFFERENT custom value! ({})",
                 self.something
             ),
             span,
-        })
+        ))
     }
 
     fn as_any(&self) -> &dyn std::any::Any {