refactor(derive): Remove proc-macro-error dependency

Made things simpler that we were always aborting before.
clap-rs · Mar 18, 2023 · e030426 · e030426
1 parent cc1474f
commit e030426
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Showing 15 changed files with 666 additions and 597 deletions.
diff --git a/Cargo.lock b/Cargo.lock
diff --git a/clap_derive/Cargo.toml b/clap_derive/Cargo.toml
@@ -33,7 +33,6 @@ syn = { version = "1.0.74", features = ["full"] }
 quote = "1.0.9"
 proc-macro2 = "1.0.42"
 heck = "0.4.0"
-proc-macro-error = "1.0.4"
 
 [features]
 default = []

diff --git a/clap_derive/src/attr.rs b/clap_derive/src/attr.rs
@@ -1,8 +1,6 @@
 use std::iter::FromIterator;
 
 use proc_macro2::TokenStream;
-use proc_macro_error::abort;
-use proc_macro_error::ResultExt;
 use quote::quote;
 use quote::ToTokens;
 use syn::spanned::Spanned;
@@ -24,49 +22,44 @@ pub struct ClapAttr {
 }
 
 impl ClapAttr {
-    pub fn parse_all(all_attrs: &[Attribute]) -> Vec<Self> {
-        all_attrs
-            .iter()
-            .filter_map(|attr| {
-                let kind = if attr.path.is_ident("clap") {
-                    Some(Sp::new(AttrKind::Clap, attr.path.span()))
-                } else if attr.path.is_ident("structopt") {
-                    Some(Sp::new(AttrKind::StructOpt, attr.path.span()))
-                } else if attr.path.is_ident("command") {
-                    Some(Sp::new(AttrKind::Command, attr.path.span()))
-                } else if attr.path.is_ident("group") {
-                    Some(Sp::new(AttrKind::Group, attr.path.span()))
-                } else if attr.path.is_ident("arg") {
-                    Some(Sp::new(AttrKind::Arg, attr.path.span()))
-                } else if attr.path.is_ident("value") {
-                    Some(Sp::new(AttrKind::Value, attr.path.span()))
-                } else {
-                    None
-                };
-                kind.map(|k| (k, attr))
-            })
-            .flat_map(|(k, attr)| {
-                attr.parse_args_with(Punctuated::<ClapAttr, Token![,]>::parse_terminated)
-                    .unwrap_or_abort()
-                    .into_iter()
-                    .map(move |mut a| {
-                        a.kind = k;
-                        a
-                    })
-            })
-            .collect()
+    pub fn parse_all(all_attrs: &[Attribute]) -> Result<Vec<Self>, syn::Error> {
+        let mut parsed = Vec::new();
+        for attr in all_attrs {
+            let kind = if attr.path.is_ident("clap") {
+                Sp::new(AttrKind::Clap, attr.path.span())
+            } else if attr.path.is_ident("structopt") {
+                Sp::new(AttrKind::StructOpt, attr.path.span())
+            } else if attr.path.is_ident("command") {
+                Sp::new(AttrKind::Command, attr.path.span())
+            } else if attr.path.is_ident("group") {
+                Sp::new(AttrKind::Group, attr.path.span())
+            } else if attr.path.is_ident("arg") {
+                Sp::new(AttrKind::Arg, attr.path.span())
+            } else if attr.path.is_ident("value") {
+                Sp::new(AttrKind::Value, attr.path.span())
+            } else {
+                continue;
+            };
+            for mut attr in
+                attr.parse_args_with(Punctuated::<ClapAttr, Token![,]>::parse_terminated)?
+            {
+                attr.kind = kind;
+                parsed.push(attr);
+            }
+        }
+        Ok(parsed)
     }
 
-    pub fn value_or_abort(&self) -> &AttrValue {
+    pub fn value_or_abort(&self) -> Result<&AttrValue, syn::Error> {
         self.value
             .as_ref()
-            .unwrap_or_else(|| abort!(self.name, "attribute `{}` requires a value", self.name))
+            .ok_or_else(|| format_err!(self.name, "attribute `{}` requires a value", self.name))
     }
 
-    pub fn lit_str_or_abort(&self) -> &LitStr {
-        let value = self.value_or_abort();
+    pub fn lit_str_or_abort(&self) -> Result<&LitStr, syn::Error> {
+        let value = self.value_or_abort()?;
         match value {
-            AttrValue::LitStr(tokens) => tokens,
+            AttrValue::LitStr(tokens) => Ok(tokens),
             AttrValue::Expr(_) | AttrValue::Call(_) => {
                 abort!(
                     self.name,