syntax: Make def-site span mandatory in ExpnInfo/MacroBacktrace/DiagnosticSpanMacroExpansion

We have to deal with dummy spans anyway

Remove def-site span from expander interfaces.
It's not used by the expansion infra, only by specific expanders, which can keep it themselves if they want it.

4 files changed, 12 insertions, 17 deletions

diff --git a/src/libsyntax/ext/base.rs b/src/libsyntax/ext/base.rs
index 267046655ff..2f8d6f00ba7 100644
--- a/src/libsyntax/ext/base.rs
+++ b/src/libsyntax/ext/base.rs
@@ -219,7 +219,6 @@ pub trait TTMacroExpander {
         ecx: &'cx mut ExtCtxt<'_>,
         span: Span,
         input: TokenStream,
-        def_span: Option<Span>,
     ) -> Box<dyn MacResult+'cx>;
 }
 
@@ -236,7 +235,6 @@ impl<F> TTMacroExpander for F
         ecx: &'cx mut ExtCtxt<'_>,
         span: Span,
         input: TokenStream,
-        _def_span: Option<Span>,
     ) -> Box<dyn MacResult+'cx> {
         struct AvoidInterpolatedIdents;
 
@@ -654,7 +652,7 @@ impl SyntaxExtension {
         ExpnInfo {
             call_site,
             kind: self.expn_kind(Symbol::intern(descr)),
-            def_site: Some(self.span),
+            def_site: self.span,
             default_transparency: self.default_transparency,
             allow_internal_unstable: self.allow_internal_unstable.clone(),
             allow_internal_unsafe: self.allow_internal_unsafe,
diff --git a/src/libsyntax/ext/expand.rs b/src/libsyntax/ext/expand.rs
index bb7d7352e05..06ff2bc655c 100644
--- a/src/libsyntax/ext/expand.rs
+++ b/src/libsyntax/ext/expand.rs
@@ -673,7 +673,7 @@ impl<'a, 'b> MacroExpander<'a, 'b> {
                 result
             }
             SyntaxExtensionKind::LegacyBang(expander) => {
-                let tok_result = expander.expand(self.cx, span, mac.node.stream(), Some(ext.span));
+                let tok_result = expander.expand(self.cx, span, mac.node.stream());
                 kind.make_from(tok_result)
             }
 
diff --git a/src/libsyntax/ext/tt/macro_rules.rs b/src/libsyntax/ext/tt/macro_rules.rs
index 665c794422d..5c6438a7ef5 100644
--- a/src/libsyntax/ext/tt/macro_rules.rs
+++ b/src/libsyntax/ext/tt/macro_rules.rs
@@ -88,6 +88,7 @@ impl<'a> ParserAnyMacro<'a> {
 
 struct MacroRulesMacroExpander {
     name: ast::Ident,
+    span: Span,
     lhses: Vec<quoted::TokenTree>,
     rhses: Vec<quoted::TokenTree>,
     valid: bool,
@@ -99,12 +100,11 @@ impl TTMacroExpander for MacroRulesMacroExpander {
         cx: &'cx mut ExtCtxt<'_>,
         sp: Span,
         input: TokenStream,
-        def_span: Option<Span>,
     ) -> Box<dyn MacResult + 'cx> {
         if !self.valid {
             return DummyResult::any(sp);
         }
-        generic_extension(cx, sp, def_span, self.name, input, &self.lhses, &self.rhses)
+        generic_extension(cx, sp, self.span, self.name, input, &self.lhses, &self.rhses)
     }
 }
 
@@ -117,7 +117,7 @@ fn trace_macros_note(cx: &mut ExtCtxt<'_>, sp: Span, message: String) {
 fn generic_extension<'cx>(
     cx: &'cx mut ExtCtxt<'_>,
     sp: Span,
-    def_span: Option<Span>,
+    def_span: Span,
     name: ast::Ident,
     arg: TokenStream,
     lhses: &[quoted::TokenTree],
@@ -199,10 +199,8 @@ fn generic_extension<'cx>(
     let span = token.span.substitute_dummy(sp);
     let mut err = cx.struct_span_err(span, &parse_failure_msg(&token));
     err.span_label(span, label);
-    if let Some(sp) = def_span {
-        if cx.source_map().span_to_filename(sp).is_real() && !sp.is_dummy() {
-            err.span_label(cx.source_map().def_span(sp), "when calling this macro");
-        }
+    if !def_span.is_dummy() && cx.source_map().span_to_filename(def_span).is_real() {
+        err.span_label(cx.source_map().def_span(def_span), "when calling this macro");
     }
 
     // Check whether there's a missing comma in this macro call, like `println!("{}" a);`
@@ -377,7 +375,7 @@ pub fn compile(
     }
 
     let expander: Box<_> =
-        Box::new(MacroRulesMacroExpander { name: def.ident, lhses, rhses, valid });
+        Box::new(MacroRulesMacroExpander { name: def.ident, span: def.span, lhses, rhses, valid });
 
     let (default_transparency, transparency_error) =
         attr::find_transparency(&def.attrs, body.legacy);
diff --git a/src/libsyntax/json.rs b/src/libsyntax/json.rs
index 767ab74355e..ec0222d90eb 100644
--- a/src/libsyntax/json.rs
+++ b/src/libsyntax/json.rs
@@ -170,7 +170,7 @@ struct DiagnosticSpanMacroExpansion {
     macro_decl_name: String,
 
     /// span where macro was defined (if known)
-    def_site_span: Option<DiagnosticSpan>,
+    def_site_span: DiagnosticSpan,
 }
 
 #[derive(RustcEncodable)]
@@ -300,14 +300,13 @@ impl DiagnosticSpan {
                                      None,
                                      backtrace,
                                      je);
-            let def_site_span = bt.def_site_span.map(|sp| {
-                Self::from_span_full(sp,
+            let def_site_span =
+                Self::from_span_full(bt.def_site_span,
                                      false,
                                      None,
                                      None,
                                      vec![].into_iter(),
-                                     je)
-            });
+                                     je);
             Box::new(DiagnosticSpanMacroExpansion {
                 span: call_site,
                 macro_decl_name: bt.macro_decl_name,