strip out proc-macro-hack

abonander · abonander · commit da5c538d22be · 2020-01-15T00:05:09.000-08:00
diff --git a/Cargo.lock b/Cargo.lock
diff --git a/Cargo.toml b/Cargo.toml
@@ -29,7 +29,7 @@ all-features = true
 
 [features]
 default = [ "macros" ]
-macros = [ "sqlx-macros", "proc-macro-hack" ]
+macros = [ "sqlx-macros" ]
 tls = ["sqlx-core/tls"]
 
 # database
@@ -43,7 +43,6 @@ uuid = [ "sqlx-core/uuid", "sqlx-macros/uuid" ]
 [dependencies]
 sqlx-core = { version = "=0.1.4", path = "sqlx-core" }
 sqlx-macros = { version = "0.1.1", path = "sqlx-macros", optional = true }
-proc-macro-hack = { version = "0.5.11", optional = true }
 
 [dev-dependencies]
 anyhow = "1.0.26"
diff --git a/sqlx-macros/Cargo.toml b/sqlx-macros/Cargo.toml
@@ -33,7 +33,6 @@ uuid = [ "sqlx/uuid" ]
 async-std = { version = "1.4.0", default-features = false }
 dotenv = { version = "0.15.0", default-features = false }
 futures = { version = "0.3.1", default-features = false }
-proc-macro-hack = { version = "0.5.11", default-features = false }
 proc-macro2 = { version = "1.0.6", default-features = false }
 sqlx = { version = "0.1.1", default-features = false, path = "../sqlx-core", package = "sqlx-core" }
 syn = { version = "1.0.11", default-features = false, features = [ "full" ] }
diff --git a/sqlx-macros/src/lib.rs b/sqlx-macros/src/lib.rs
@@ -6,8 +6,6 @@ extern crate proc_macro;
 
 use proc_macro::TokenStream;
 
-use proc_macro_hack::proc_macro_hack;
-
 use quote::quote;
 
 use syn::parse_macro_input;
@@ -26,8 +24,22 @@ mod query_macros;
 
 use query_macros::*;
 
+fn macro_result(tokens: proc_macro2::TokenStream) -> TokenStream {
+    quote!(
+        macro_rules! macro_result {
+            ($($args:tt)*) => (#tokens)
+        }
+    )
+    .into()
+}
+
 macro_rules! async_macro (
-    ($db:ident => $expr:expr) => {{
+    ($db:ident, $input:ident: $ty:ty => $expr:expr) => {{
+        let $input = match syn::parse::<$ty>($input) {
+            Ok(input) => input,
+            Err(e) => return macro_result(e.to_compile_error()),
+        };
+
         let res: Result<proc_macro2::TokenStream> = task::block_on(async {
             use sqlx::Connection;
 
@@ -70,40 +82,36 @@ macro_rules! async_macro (
             Ok(ts) => ts.into(),
             Err(e) => {
                 if let Some(parse_err) = e.downcast_ref::<syn::Error>() {
-                    return dbg!(parse_err).to_compile_error().into();
+                    macro_result(parse_err.to_compile_error())
+                } else {
+                    let msg = format!("{:?}", e);
+                    macro_result(quote!(compile_error(#msg)))
                 }
-
-                let msg = format!("{:?}", e);
-                quote!(compile_error!(#msg);).into()
             }
         }
     }}
 );
 
-#[proc_macro_hack]
+#[proc_macro]
 pub fn query(input: TokenStream) -> TokenStream {
     #[allow(unused_variables)]
-    let input = parse_macro_input!(input as QueryMacroInput);
-    async_macro!(db => expand_query(input, db))
+    async_macro!(db, input: QueryMacroInput => expand_query(input, db))
 }
 
-#[proc_macro_hack]
+#[proc_macro]
 pub fn query_file(input: TokenStream) -> TokenStream {
     #[allow(unused_variables)]
-    let input = parse_macro_input!(input as QueryMacroInput);
-    async_macro!(db => expand_query_file(input, db))
+    async_macro!(db, input: QueryMacroInput => expand_query_file(input, db))
 }
 
-#[proc_macro_hack]
+#[proc_macro]
 pub fn query_as(input: TokenStream) -> TokenStream {
     #[allow(unused_variables)]
-    let input = parse_macro_input!(input as QueryAsMacroInput);
-    async_macro!(db => expand_query_as(input, db))
+    async_macro!(db, input: QueryAsMacroInput => expand_query_as(input, db))
 }
 
-#[proc_macro_hack]
+#[proc_macro]
 pub fn query_file_as(input: TokenStream) -> TokenStream {
     #[allow(unused_variables)]
-    let input = parse_macro_input!(input as QueryAsMacroInput);
-    async_macro!(db => expand_query_file_as(input, db))
+    async_macro!(db, input: QueryAsMacroInput => expand_query_file_as(input, db))
 }
diff --git a/sqlx-macros/src/query_macros/args.rs b/sqlx-macros/src/query_macros/args.rs
@@ -12,7 +12,7 @@ pub fn quote_args<DB: DatabaseExt>(
     input: &QueryMacroInput,
     describe: &Describe<DB>,
 ) -> crate::Result<TokenStream> {
-    if input.args.is_empty() {
+    if input.arg_names.is_empty() {
         return Ok(quote! {
             let args = ();
         });
@@ -22,7 +22,7 @@ pub fn quote_args<DB: DatabaseExt>(
         let param_types = describe
             .param_types
             .iter()
-            .zip(&*input.args)
+            .zip(&*input.arg_exprs)
             .map(|(type_, expr)| {
                 get_type_override(expr)
                     .or_else(|| {
@@ -36,7 +36,7 @@ pub fn quote_args<DB: DatabaseExt>(
             })
             .collect::<crate::Result<Vec<_>>>()?;
 
-        let args_ty_cons = input.args.iter().enumerate().map(|(i, expr)| {
+        let args_ty_cons = input.arg_names.iter().enumerate().map(|(i, expr)| {
             // required or `quote!()` emits it as `Nusize`
             let i = syn::Index::from(i);
             quote_spanned!( expr.span() => {
@@ -56,10 +56,10 @@ pub fn quote_args<DB: DatabaseExt>(
         TokenStream::new()
     };
 
-    let args = input.args.iter();
+    let args = input.arg_names.iter();
 
     Ok(quote! {
-        let args = (#(&#args),*,);
+        let args = (#(&$#args),*,);
         #args_check
     })
 }
diff --git a/sqlx-macros/src/query_macros/input.rs b/sqlx-macros/src/query_macros/input.rs
@@ -1,11 +1,15 @@
 use std::env;
 
 use async_std::fs;
-use proc_macro2::Span;
+use proc_macro2::{Ident, Span, TokenStream};
 use syn::parse::{Parse, ParseStream};
 use syn::punctuated::Punctuated;
-use syn::Token;
+use syn::spanned::Spanned;
+use syn::token::Group;
 use syn::{Expr, ExprLit, ExprPath, Lit};
+use syn::{ExprGroup, Token};
+
+use quote::{format_ident, quote, ToTokens};
 
 use sqlx::describe::Describe;
 use sqlx::Connection;
@@ -14,28 +18,55 @@ use sqlx::Connection;
 pub struct QueryMacroInput {
     pub(super) source: String,
     pub(super) source_span: Span,
-    pub(super) args: Vec<Expr>,
+    // `arg0 .. argN` for N arguments
+    pub(super) arg_names: Vec<Ident>,
+    pub(super) arg_exprs: Vec<Expr>,
 }
 
 impl QueryMacroInput {
     fn from_exprs(input: ParseStream, mut args: impl Iterator<Item = Expr>) -> syn::Result<Self> {
-        let sql = match args.next() {
+        fn lit_err<T>(span: Span, unexpected: Expr) -> syn::Result<T> {
+            Err(syn::Error::new(
+                span,
+                format!(
+                    "expected string literal, got {}",
+                    unexpected.to_token_stream()
+                ),
+            ))
+        }
+
+        let (source, source_span) = match args.next() {
             Some(Expr::Lit(ExprLit {
                 lit: Lit::Str(sql), ..
-            })) => sql,
-            Some(other_expr) => {
-                return Err(syn::Error::new_spanned(
-                    other_expr,
-                    "expected string literal",
-                ));
+            })) => (sql.value(), sql.span()),
+            Some(Expr::Group(ExprGroup {
+                expr,
+                group_token: Group { span },
+                ..
+            })) => {
+                // this duplication with the above is necessary because `expr` is `Box<Expr>` here
+                // which we can't directly pattern-match without `box_patterns`
+                match *expr {
+                    Expr::Lit(ExprLit {
+                        lit: Lit::Str(sql), ..
+                    }) => (sql.value(), span),
+                    other_expr => return lit_err(span, other_expr),
+                }
             }
+            Some(other_expr) => return lit_err(other_expr.span(), other_expr),
             None => return Err(input.error("expected SQL string literal")),
         };
 
+        let arg_exprs: Vec<_> = args.collect();
+        let arg_names = (0..arg_exprs.len())
+            .map(|i| format_ident!("arg{}", i))
+            .collect();
+
         Ok(Self {
-            source: sql.value(),
-            source_span: sql.span(),
-            args: args.collect(),
+            source,
+            source_span,
+            arg_exprs,
+            arg_names,
         })
     }
 
@@ -56,13 +87,13 @@ impl QueryMacroInput {
             .await
             .map_err(|e| syn::Error::new(self.source_span, e))?;
 
-        if self.args.len() != describe.param_types.len() {
+        if self.arg_names.len() != describe.param_types.len() {
             return Err(syn::Error::new(
                 Span::call_site(),
                 format!(
                     "expected {} parameters, got {}",
                     describe.param_types.len(),
-                    self.args.len()
+                    self.arg_names.len()
                 ),
             )
             .into());
@@ -97,16 +128,33 @@ impl QueryAsMacroInput {
 
 impl Parse for QueryAsMacroInput {
     fn parse(input: ParseStream) -> syn::Result<Self> {
+        fn path_err<T>(span: Span, unexpected: Expr) -> syn::Result<T> {
+            Err(syn::Error::new(
+                span,
+                format!(
+                    "expected path to a type, got {}",
+                    unexpected.to_token_stream()
+                ),
+            ))
+        }
+
         let mut args = Punctuated::<Expr, Token![,]>::parse_terminated(input)?.into_iter();
 
         let as_ty = match args.next() {
             Some(Expr::Path(path)) => path,
-            Some(other_expr) => {
-                return Err(syn::Error::new_spanned(
-                    other_expr,
-                    "expected path to a type",
-                ));
+            Some(Expr::Group(ExprGroup {
+                expr,
+                group_token: Group { span },
+                ..
+            })) => {
+                // this duplication with the above is necessary because `expr` is `Box<Expr>` here
+                // which we can't directly pattern-match without `box_patterns`
+                match *expr {
+                    Expr::Path(path) => path,
+                    other_expr => return path_err(span, other_expr),
+                }
             }
+            Some(other_expr) => return path_err(other_expr.span(), other_expr),
             None => return Err(input.error("expected path to SQL file")),
         };
 
diff --git a/sqlx-macros/src/query_macros/mod.rs b/sqlx-macros/src/query_macros/mod.rs
@@ -46,6 +46,7 @@ where
     }
 
     let args_tokens = args::quote_args(&input.query_input, &describe)?;
+    let arg_names = &input.query_input.arg_names;
 
     let columns = output::columns_to_rust(&describe)?;
     let output = output::quote_query_as::<C::Database>(
@@ -54,10 +55,14 @@ where
         &columns,
     );
 
-    Ok(quote! {{
-        #args_tokens
-        #output.bind_all(args)
-    }})
+    Ok(quote! {
+        macro_rules! macro_result {
+            (#($#arg_names:expr),*) => {{
+                #args_tokens
+                #output.bind_all(args)
+            }}
+        }
+    })
 }
 
 pub async fn expand_query_file_as<C: Connection>(
diff --git a/sqlx-macros/src/query_macros/query.rs b/sqlx-macros/src/query_macros/query.rs
@@ -50,15 +50,20 @@ where
         .collect::<TokenStream>();
 
     let output = output::quote_query_as::<C::Database>(sql, &record_type, &columns);
+    let arg_names = &input.arg_names;
 
-    Ok(quote! {{
-        #[derive(Debug)]
-        struct #record_type {
-            #record_fields
-        }
+    Ok(quote! {
+        macro_rules! macro_result {
+            (#($#arg_names:expr),*) => {{
+                #[derive(Debug)]
+                struct #record_type {
+                    #record_fields
+                }
 
-        #args
+                #args
 
-        #output.bind_all(args)
-    }})
+                #output.bind_all(args)
+            }
+        }}
+    })
 }
diff --git a/src/lib.rs b/src/lib.rs
@@ -20,33 +20,13 @@ pub use sqlx_core::mysql::{self, MySql, MySqlConnection, MySqlPool};
 #[cfg(feature = "postgres")]
 pub use sqlx_core::postgres::{self, PgConnection, PgPool, Postgres};
 
-#[allow(unused_attributes)]
-#[macro_export]
-mod macros;
-
-#[cfg(feature = "macros")]
-#[doc(hidden)]
-#[proc_macro_hack::proc_macro_hack(fake_call_site)]
-#[allow(dead_code)]
-pub use sqlx_macros::query as query_;
-
 #[cfg(feature = "macros")]
 #[doc(hidden)]
-#[proc_macro_hack::proc_macro_hack(fake_call_site)]
-#[allow(dead_code)]
-pub use sqlx_macros::query_as as query_as_;
+pub extern crate sqlx_macros;
 
 #[cfg(feature = "macros")]
-#[doc(hidden)]
-#[proc_macro_hack::proc_macro_hack(fake_call_site)]
-#[allow(dead_code)]
-pub use sqlx_macros::query_file as query_file_;
-
-#[cfg(feature = "macros")]
-#[doc(hidden)]
-#[proc_macro_hack::proc_macro_hack(fake_call_site)]
-#[allow(dead_code)]
-pub use sqlx_macros::query_file_as as query_file_as_;
+#[macro_export]
+mod macros;
 
 // macro support
 #[cfg(feature = "macros")]
diff --git a/src/macros.rs b/src/macros.rs
diff --git a/tests/mysql.rs b/tests/mysql.rs
