last round of cleanups. coffee is neat

pgcentralfoundation · Oct 27, 2024 · 6f0cebc · 6f0cebc
1 parent 32e949d
commit 6f0cebc
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Showing 2 changed files with 25 additions and 11 deletions.
diff --git a/pgrx-macros/src/lib.rs b/pgrx-macros/src/lib.rs
@@ -186,21 +186,18 @@ pub fn pg_cast(attr: TokenStream, item: TokenStream) -> TokenStream {
             Ok(paths) => {
                 let mut new_paths = Punctuated::<syn::Path, syn::Token![,]>::new();
                 for path in paths {
-                    if path.is_ident("implicit") {
-                        if let Some(cast) = &cast {
-                            panic!("The cast type has already been set to `{cast:?}`");
+                    match (PgCast::try_from(path), &cast) {
+                        (Ok(style), None) => cast = Some(style),
+                        (Ok(_), Some(cast)) => {
+                            panic!("The cast type has already been set to `{cast:?}`")
                         }
-                        cast = Some(PgCast::Implicit);
-                    } else if path.is_ident("assignment") {
-                        if let Some(cast) = &cast {
-                            panic!("The cast type has already been set to `{cast:?}`");
-                        }
-                        cast = Some(PgCast::Assignment);
-                    } else {
+
                         // ... and anything it doesn't understand is blindly passed through to the
                         // underlying `#[pg_extern]` function that gets created, which will ultimately
                         // decide what's naughty and what's nice
-                        new_paths.push(path);
+                        (Err(unknown), _) => {
+                            new_paths.push(unknown);
+                        }
                     }
                 }
 

diff --git a/pgrx-sql-entity-graph/src/pg_extern/cast.rs b/pgrx-sql-entity-graph/src/pg_extern/cast.rs
@@ -17,6 +17,7 @@
 */
 use proc_macro2::TokenStream as TokenStream2;
 use quote::{quote, ToTokens, TokenStreamExt};
+use syn::Path;
 
 /// A parsed `#[pg_cast]` operator.
 ///
@@ -29,6 +30,22 @@ pub enum PgCast {
     Implicit,
 }
 
+pub type InvalidCastStyle = Path;
+
+impl TryFrom<Path> for PgCast {
+    type Error = InvalidCastStyle;
+
+    fn try_from(path: Path) -> Result<Self, Self::Error> {
+        if path.is_ident("implicit") {
+            Ok(Self::Implicit)
+        } else if path.is_ident("assignment") {
+            Ok(Self::Assignment)
+        } else {
+            Err(path)
+        }
+    }
+}
+
 impl ToTokens for PgCast {
     fn to_tokens(&self, tokens: &mut TokenStream2) {
         let quoted = match self {