Mark top-level items as pub(crate)

this way we'll get better compiler diagnostics (for example it'll warn
against unused fields and such).

src/attr.rs

@@ -3,7 +3,7 @@ use syn::{
     LitStr, Token,
 };
 
-pub enum BotCommandAttribute {
+pub(crate) enum BotCommandAttribute {
     Prefix,
     Description,
     RenameRule,
@@ -25,7 +25,7 @@ impl Parse for BotCommandAttribute {
     }
 }
 
-pub struct Attr {
+pub(crate) struct Attr {
     name: BotCommandAttribute,
     value: String,
 }
@@ -50,7 +50,7 @@ impl Attr {
     }
 }
 
-pub struct VecAttrs {
+pub(crate) struct VecAttrs {
     pub data: Vec<Attr>,
 }
 

src/command.rs

@@ -66,11 +66,11 @@ impl Command {
 }
 
 pub(crate) struct CommandAttrs {
-    pub(crate) prefix: Option<String>,
-    pub(crate) description: Option<String>,
-    pub(crate) rename: Option<String>,
-    pub(crate) parser: Option<ParserType>,
-    pub(crate) separator: Option<String>,
+    pub prefix: Option<String>,
+    pub description: Option<String>,
+    pub rename: Option<String>,
+    pub parser: Option<ParserType>,
+    pub separator: Option<String>,
 }
 
 pub(crate) fn parse_attrs(attrs: &[Attr]) -> Result<CommandAttrs> {

src/fields_parse.rs

@@ -4,7 +4,7 @@ use quote::{quote, ToTokens};
 use syn::{FieldsNamed, FieldsUnnamed, Type};
 
 #[derive(Debug)]
-pub enum ParserType {
+pub(crate) enum ParserType {
     Default,
     Split { separator: Option<String> },
     Custom(String),
@@ -20,7 +20,7 @@ impl ParserType {
     }
 }
 
-pub fn impl_parse_args_unnamed(
+pub(crate) fn impl_parse_args_unnamed(
     data: &FieldsUnnamed,
     variant: impl ToTokens,
     parser_type: &ParserType,
@@ -44,7 +44,7 @@ pub fn impl_parse_args_unnamed(
     res
 }
 
-pub fn impl_parse_args_named(
+pub(crate) fn impl_parse_args_named(
     data: &FieldsNamed,
     variant: impl ToTokens,
     parser_type: &ParserType,

src/rename_rules.rs

@@ -11,7 +11,7 @@ use heck::{
 /// The possible `rule` can be: `lowercase`, `UPPERCASE`, `PascalCase`,
 /// `camelCase`, `snake_case`, `SCREAMING_SNAKE_CASE`, `kebab-case`,
 /// `SCREAMING-KEBAB-CASE`. See tests for the details how it will work.
-pub fn rename_by_rule(input: &str, rule: &str) -> String {
+pub(crate) fn rename_by_rule(input: &str, rule: &str) -> String {
     match rule {
         "lowercase" => input.to_lowercase(),
         "UPPERCASE" => input.to_uppercase(),