Auto merge of #52121 - jebrosen:macros2_feature, r=petrochenkov

Merge `proc_macro_` expansion feature gates as `proc_macro_hygiene`

Merges `proc_macro_mod`, `proc_macro_expr`, `proc_macro_non_items`, and `proc_macro_gen` into a single feature: `proc_macro_hygiene`. These features are not all blocked on implementing macro hygiene *per se*, but rather on interactions with hygiene that have not been entirely resolved.

src/libsyntax/ext/expand.rs

@@ -645,8 +645,8 @@ impl<'a, 'b> MacroExpander<'a, 'b> {
         let (kind, gate) = match *item {
             Annotatable::Item(ref item) => {
                 match item.node {
-                    ItemKind::Mod(_) if self.cx.ecfg.proc_macro_mod() => return,
-                    ItemKind::Mod(_) => ("modules", "proc_macro_mod"),
+                    ItemKind::Mod(_) if self.cx.ecfg.proc_macro_hygiene() => return,
+                    ItemKind::Mod(_) => ("modules", "proc_macro_hygiene"),
                     _ => return,
                 }
             }
@@ -654,9 +654,9 @@ impl<'a, 'b> MacroExpander<'a, 'b> {
             Annotatable::ImplItem(_) => return,
             Annotatable::ForeignItem(_) => return,
             Annotatable::Stmt(_) |
-            Annotatable::Expr(_) if self.cx.ecfg.proc_macro_expr() => return,
-            Annotatable::Stmt(_) => ("statements", "proc_macro_expr"),
-            Annotatable::Expr(_) => ("expressions", "proc_macro_expr"),
+            Annotatable::Expr(_) if self.cx.ecfg.proc_macro_hygiene() => return,
+            Annotatable::Stmt(_) => ("statements", "proc_macro_hygiene"),
+            Annotatable::Expr(_) => ("expressions", "proc_macro_hygiene"),
         };
         emit_feature_err(
             self.cx.parse_sess,
@@ -668,7 +668,7 @@ impl<'a, 'b> MacroExpander<'a, 'b> {
     }
 
     fn gate_proc_macro_expansion(&self, span: Span, fragment: &Option<AstFragment>) {
-        if self.cx.ecfg.proc_macro_gen() {
+        if self.cx.ecfg.proc_macro_hygiene() {
             return
         }
         let fragment = match fragment {
@@ -691,7 +691,7 @@ impl<'a, 'b> MacroExpander<'a, 'b> {
                 if let ast::ItemKind::MacroDef(_) = i.node {
                     emit_feature_err(
                         self.parse_sess,
-                        "proc_macro_gen",
+                        "proc_macro_hygiene",
                         self.span,
                         GateIssue::Language,
                         &format!("procedural macros cannot expand to macro definitions"),
@@ -885,12 +885,12 @@ impl<'a, 'b> MacroExpander<'a, 'b> {
             AstFragmentKind::ImplItems => return,
             AstFragmentKind::ForeignItems => return,
         };
-        if self.cx.ecfg.proc_macro_non_items() {
+        if self.cx.ecfg.proc_macro_hygiene() {
             return
         }
         emit_feature_err(
             self.cx.parse_sess,
-            "proc_macro_non_items",
+            "proc_macro_hygiene",
             span,
             GateIssue::Language,
             &format!("procedural macros cannot be expanded to {}", kind),
@@ -1612,10 +1612,7 @@ impl<'feat> ExpansionConfig<'feat> {
         fn enable_custom_derive = custom_derive,
         fn enable_format_args_nl = format_args_nl,
         fn macros_in_extern_enabled = macros_in_extern,
-        fn proc_macro_mod = proc_macro_mod,
-        fn proc_macro_gen = proc_macro_gen,
-        fn proc_macro_expr = proc_macro_expr,
-        fn proc_macro_non_items = proc_macro_non_items,
+        fn proc_macro_hygiene = proc_macro_hygiene,
     }
 
     fn enable_custom_inner_attributes(&self) -> bool {

src/libsyntax/feature_gate.rs

@@ -441,10 +441,7 @@ declare_features! (
 
     // Allows macro invocations on modules expressions and statements and
     // procedural macros to expand to non-items.
-    (active, proc_macro_mod, "1.27.0", Some(54727), None),
-    (active, proc_macro_expr, "1.27.0", Some(54727), None),
-    (active, proc_macro_non_items, "1.27.0", Some(54727), None),
-    (active, proc_macro_gen, "1.27.0", Some(54727), None),
+    (active, proc_macro_hygiene, "1.30.0", Some(54727), None),
 
     // #[doc(alias = "...")]
     (active, doc_alias, "1.27.0", Some(50146), None),
@@ -541,6 +538,14 @@ declare_features! (
      Some("merged into `#![feature(slice_patterns)]`")),
     (removed, macro_reexport, "1.0.0", Some(29638), None,
      Some("subsumed by `pub use`")),
+    (removed, proc_macro_mod, "1.27.0", Some(54727), None,
+     Some("subsumed by `#![feature(proc_macro_hygiene)]`")),
+    (removed, proc_macro_expr, "1.27.0", Some(54727), None,
+     Some("subsumed by `#![feature(proc_macro_hygiene)]`")),
+    (removed, proc_macro_non_items, "1.27.0", Some(54727), None,
+     Some("subsumed by `#![feature(proc_macro_hygiene)]`")),
+    (removed, proc_macro_gen, "1.27.0", Some(54727), None,
+     Some("subsumed by `#![feature(proc_macro_hygiene)]`")),
 );
 
 declare_features! (

src/test/compile-fail-fulldeps/proc-macro/attr-invalid-exprs.rs

@@ -13,7 +13,7 @@
 
 //! Attributes producing expressions in invalid locations
 
-#![feature(stmt_expr_attributes, proc_macro_expr)]
+#![feature(stmt_expr_attributes, proc_macro_hygiene)]
 
 extern crate attr_stmt_expr;
 use attr_stmt_expr::{duplicate, no_output};

src/test/compile-fail-fulldeps/proc-macro/attr-stmt-expr.rs

@@ -11,7 +11,7 @@
 // aux-build:attr-stmt-expr.rs
 // ignore-stage1
 
-#![feature(proc_macro_expr)]
+#![feature(proc_macro_hygiene)]
 
 extern crate attr_stmt_expr;
 use attr_stmt_expr::{expect_let, expect_print_stmt, expect_expr, expect_print_expr};

src/test/compile-fail-fulldeps/proc-macro/lints_in_proc_macros.rs

@@ -11,7 +11,7 @@
 // aux-build:bang_proc_macro2.rs
 // ignore-stage1
 
-#![feature(proc_macro_non_items)]
+#![feature(proc_macro_hygiene)]
 #![allow(unused_macros)]
 
 extern crate bang_proc_macro2;

src/test/compile-fail-fulldeps/proc-macro/proc-macro-gates.rs

@@ -9,11 +9,7 @@
 // except according to those terms.
 
 // aux-build:proc-macro-gates.rs
-// gate-test-proc_macro_non_items
-// gate-test-proc_macro_mod line
-// gate-test-proc_macro_expr
-// gate-test-proc_macro_mod
-// gate-test-proc_macro_gen
+// gate-test-proc_macro_hygiene
 
 #![feature(stmt_expr_attributes)]
 

src/test/run-pass-fulldeps/auxiliary/cond_plugin.rs

@@ -11,7 +11,7 @@
 // no-prefer-dynamic
 
 #![crate_type = "proc-macro"]
-#![feature(proc_macro_non_items)]
+#![feature(proc_macro_hygiene)]
 
 extern crate proc_macro;
 

src/test/run-pass-fulldeps/auxiliary/hello_macro.rs

@@ -11,7 +11,7 @@
 // no-prefer-dynamic
 
 #![crate_type = "proc-macro"]
-#![feature(proc_macro_non_items, proc_macro_quote)]
+#![feature(proc_macro_hygiene, proc_macro_quote)]
 
 extern crate proc_macro;
 

src/test/run-pass-fulldeps/auxiliary/proc_macro_def.rs

@@ -11,7 +11,7 @@
 // no-prefer-dynamic
 
 #![crate_type = "proc-macro"]
-#![feature(proc_macro_non_items)]
+#![feature(proc_macro_hygiene)]
 
 extern crate proc_macro;
 

src/test/run-pass-fulldeps/macro-quote-cond.rs

@@ -12,7 +12,7 @@
 // aux-build:cond_plugin.rs
 // ignore-stage1
 
-#![feature(proc_macro_non_items)]
+#![feature(proc_macro_hygiene)]
 
 extern crate cond_plugin;
 

src/test/run-pass-fulldeps/macro-quote-test.rs

@@ -13,7 +13,7 @@
 // aux-build:hello_macro.rs
 // ignore-stage1
 
-#![feature(proc_macro_non_items, proc_macro_gen)]
+#![feature(proc_macro_hygiene)]
 
 extern crate hello_macro;
 

src/test/run-pass-fulldeps/proc-macro/attr-stmt-expr.rs

@@ -11,7 +11,7 @@
 // aux-build:attr-stmt-expr.rs
 // ignore-stage1
 
-#![feature(stmt_expr_attributes, proc_macro_expr)]
+#![feature(stmt_expr_attributes, proc_macro_hygiene)]
 
 extern crate attr_stmt_expr;
 use attr_stmt_expr::{expect_let, expect_print_stmt, expect_expr, expect_print_expr,

src/test/run-pass-fulldeps/proc-macro/auxiliary/count_compound_ops.rs

@@ -10,7 +10,7 @@
 
 // no-prefer-dynamic
 
-#![feature(proc_macro_non_items, proc_macro_quote)]
+#![feature(proc_macro_hygiene, proc_macro_quote)]
 #![crate_type = "proc-macro"]
 
 extern crate proc_macro;

src/test/run-pass-fulldeps/proc-macro/auxiliary/hygiene_example_codegen.rs

@@ -10,7 +10,7 @@
 
 // no-prefer-dynamic
 
-#![feature(proc_macro_quote, proc_macro_non_items)]
+#![feature(proc_macro_quote, proc_macro_hygiene)]
 #![crate_type = "proc-macro"]
 
 extern crate proc_macro as proc_macro_renamed; // This does not break `quote!`

src/test/run-pass-fulldeps/proc-macro/bang-macro.rs

@@ -11,7 +11,7 @@
 // aux-build:bang-macro.rs
 // ignore-stage1
 
-#![feature(proc_macro_non_items)]
+#![feature(proc_macro_hygiene)]
 
 extern crate bang_macro;
 use bang_macro::rewrite;

src/test/run-pass-fulldeps/proc-macro/call-site.rs

@@ -13,7 +13,7 @@
 // aux-build:call-site.rs
 // ignore-stage1
 
-#![feature(proc_macro_non_items)]
+#![feature(proc_macro_hygiene)]
 
 extern crate call_site;
 use call_site::*;

src/test/run-pass-fulldeps/proc-macro/count_compound_ops.rs

@@ -11,7 +11,7 @@
 // aux-build:count_compound_ops.rs
 // ignore-stage1
 
-#![feature(proc_macro_non_items)]
+#![feature(proc_macro_hygiene)]
 
 extern crate count_compound_ops;
 use count_compound_ops::count_compound_ops;

src/test/run-pass-fulldeps/proc-macro/hygiene_example.rs

@@ -13,7 +13,7 @@
 // aux-build:hygiene_example.rs
 // ignore-stage1
 
-#![feature(proc_macro_non_items)]
+#![feature(proc_macro_hygiene)]
 
 extern crate hygiene_example;
 use hygiene_example::hello;

src/test/run-pass-fulldeps/proc-macro/negative-token.rs

@@ -11,7 +11,7 @@
 // aux-build:negative-token.rs
 // ignore-stage1
 
-#![feature(proc_macro_non_items)]
+#![feature(proc_macro_hygiene)]
 
 extern crate negative_token;
 

src/test/run-pass-fulldeps/proc_macro.rs

@@ -12,7 +12,7 @@
 // ignore-stage1
 // ignore-cross-compile
 
-#![feature(proc_macro_non_items)]
+#![feature(proc_macro_hygiene)]
 
 extern crate proc_macro_def;
 

src/test/ui-fulldeps/lifetimes.rs

@@ -10,7 +10,7 @@
 
 // aux-build:lifetimes.rs
 
-#![feature(proc_macro_non_items)]
+#![feature(proc_macro_hygiene)]
 
 extern crate lifetimes;
 

src/test/ui-fulldeps/proc-macro/macro-use-bang.rs

@@ -11,7 +11,7 @@
 // compile-pass
 // aux-build:bang_proc_macro.rs
 
-#![feature(proc_macro_non_items)]
+#![feature(proc_macro_hygiene)]
 
 #[macro_use]
 extern crate bang_proc_macro;

src/test/ui-fulldeps/proc-macro/multispan.rs

@@ -11,7 +11,7 @@
 // aux-build:multispan.rs
 // ignore-stage1
 
-#![feature(proc_macro_non_items)]
+#![feature(proc_macro_hygiene)]
 
 extern crate multispan;
 

src/test/ui-fulldeps/proc-macro/parent-source-spans.rs

@@ -11,7 +11,7 @@
 // aux-build:parent-source-spans.rs
 // ignore-stage1
 
-#![feature(decl_macro, proc_macro_non_items)]
+#![feature(decl_macro, proc_macro_hygiene)]
 
 extern crate parent_source_spans;
 

src/test/ui-fulldeps/proc-macro/three-equals.rs

@@ -11,7 +11,7 @@
 // aux-build:three-equals.rs
 // ignore-stage1
 
-#![feature(proc_macro_non_items)]
+#![feature(proc_macro_hygiene)]
 
 extern crate three_equals;