hygiene: Remove `Option`s from functions returning `ExpnInfo`

The expansion info is not optional and should always exist

4 files changed, 28 insertions, 50 deletions

diff --git a/src/librustc/lint/internal.rs b/src/librustc/lint/internal.rs
index d9ad34a5297..29106fe000b 100644
--- a/src/librustc/lint/internal.rs
+++ b/src/librustc/lint/internal.rs
@@ -9,7 +9,6 @@ use errors::Applicability;
 use rustc_data_structures::fx::FxHashMap;
 use syntax::ast::{Ident, Item, ItemKind};
 use syntax::symbol::{sym, Symbol};
-use syntax_pos::ExpnInfo;
 
 declare_tool_lint! {
     pub rustc::DEFAULT_HASH_TYPES,
@@ -228,30 +227,20 @@ impl EarlyLintPass for LintPassImpl {
         if let ItemKind::Impl(_, _, _, _, Some(lint_pass), _, _) = &item.node {
             if let Some(last) = lint_pass.path.segments.last() {
                 if last.ident.name == sym::LintPass {
-                    match &lint_pass.path.span.ctxt().outer_expn_info() {
-                        Some(info) if is_lint_pass_expansion(info) => {}
-                        _ => {
-                            cx.struct_span_lint(
-                                LINT_PASS_IMPL_WITHOUT_MACRO,
-                                lint_pass.path.span,
-                                "implementing `LintPass` by hand",
-                            )
-                            .help("try using `declare_lint_pass!` or `impl_lint_pass!` instead")
-                            .emit();
-                        }
+                    let expn_info = lint_pass.path.span.ctxt().outer_expn_info();
+                    let call_site = expn_info.call_site;
+                    if expn_info.kind.descr() != sym::impl_lint_pass &&
+                       call_site.ctxt().outer_expn_info().kind.descr() != sym::declare_lint_pass {
+                        cx.struct_span_lint(
+                            LINT_PASS_IMPL_WITHOUT_MACRO,
+                            lint_pass.path.span,
+                            "implementing `LintPass` by hand",
+                        )
+                        .help("try using `declare_lint_pass!` or `impl_lint_pass!` instead")
+                        .emit();
                     }
                 }
             }
         }
     }
 }
-
-fn is_lint_pass_expansion(expn_info: &ExpnInfo) -> bool {
-    if expn_info.kind.descr() == sym::impl_lint_pass {
-        true
-    } else if let Some(info) = expn_info.call_site.ctxt().outer_expn_info() {
-        info.kind.descr() == sym::declare_lint_pass
-    } else {
-        false
-    }
-}
diff --git a/src/librustc/lint/mod.rs b/src/librustc/lint/mod.rs
index 8cb5b1e26d9..3729ee81f5c 100644
--- a/src/librustc/lint/mod.rs
+++ b/src/librustc/lint/mod.rs
@@ -885,21 +885,16 @@ pub fn provide(providers: &mut Providers<'_>) {
 /// This is used to test whether a lint should not even begin to figure out whether it should
 /// be reported on the current node.
 pub fn in_external_macro(sess: &Session, span: Span) -> bool {
-    let info = match span.ctxt().outer_expn_info() {
-        Some(info) => info,
-        // no ExpnInfo means this span doesn't come from a macro
-        None => return false,
-    };
-
-    match info.kind {
+    let expn_info = span.ctxt().outer_expn_info();
+    match expn_info.kind {
         ExpnKind::Root | ExpnKind::Desugaring(DesugaringKind::ForLoop) => false,
         ExpnKind::Desugaring(_) => true, // well, it's "external"
         ExpnKind::Macro(MacroKind::Bang, _) => {
-            if info.def_site.is_dummy() {
+            if expn_info.def_site.is_dummy() {
                 // dummy span for the def_site means it's an external macro
                 return true;
             }
-            match sess.source_map().span_to_snippet(info.def_site) {
+            match sess.source_map().span_to_snippet(expn_info.def_site) {
                 Ok(code) => !code.starts_with("macro_rules"),
                 // no snippet = external macro or compiler-builtin expansion
                 Err(_) => true,
@@ -911,10 +906,8 @@ pub fn in_external_macro(sess: &Session, span: Span) -> bool {
 
 /// Returns whether `span` originates in a derive macro's expansion
 pub fn in_derive_expansion(span: Span) -> bool {
-    if let Some(info) = span.ctxt().outer_expn_info() {
-        if let ExpnKind::Macro(MacroKind::Derive, _) = info.kind {
-            return true;
-        }
+    if let ExpnKind::Macro(MacroKind::Derive, _) = span.ctxt().outer_expn_info().kind {
+        return true;
     }
     false
 }
diff --git a/src/librustc/traits/error_reporting.rs b/src/librustc/traits/error_reporting.rs
index 83bd5c56040..20568d4709b 100644
--- a/src/librustc/traits/error_reporting.rs
+++ b/src/librustc/traits/error_reporting.rs
@@ -36,7 +36,7 @@ use errors::{Applicability, DiagnosticBuilder};
 use std::fmt;
 use syntax::ast;
 use syntax::symbol::sym;
-use syntax_pos::{DUMMY_SP, Span, ExpnInfo, ExpnKind};
+use syntax_pos::{DUMMY_SP, Span, ExpnKind};
 
 impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
     pub fn report_fulfillment_errors(&self,
@@ -61,9 +61,9 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
             // We want to ignore desugarings here: spans are equivalent even
             // if one is the result of a desugaring and the other is not.
             let mut span = error.obligation.cause.span;
-            if let Some(ExpnInfo { kind: ExpnKind::Desugaring(_), def_site, .. })
-                    = span.ctxt().outer_expn_info() {
-                span = def_site;
+            let expn_info = span.ctxt().outer_expn_info();
+            if let ExpnKind::Desugaring(_) = expn_info.kind {
+                span = expn_info.call_site;
             }
 
             error_map.entry(span).or_default().push(
diff --git a/src/librustc/ty/query/on_disk_cache.rs b/src/librustc/ty/query/on_disk_cache.rs
index 1c5baa638c2..2286271b9eb 100644
--- a/src/librustc/ty/query/on_disk_cache.rs
+++ b/src/librustc/ty/query/on_disk_cache.rs
@@ -820,18 +820,14 @@ where
             TAG_NO_EXPANSION_INFO.encode(self)
         } else {
             let (expn_id, expn_info) = span_data.ctxt.outer_expn_with_info();
-            if let Some(expn_info) = expn_info {
-                if let Some(pos) = self.expn_info_shorthands.get(&expn_id).cloned() {
-                    TAG_EXPANSION_INFO_SHORTHAND.encode(self)?;
-                    pos.encode(self)
-                } else {
-                    TAG_EXPANSION_INFO_INLINE.encode(self)?;
-                    let pos = AbsoluteBytePos::new(self.position());
-                    self.expn_info_shorthands.insert(expn_id, pos);
-                    expn_info.encode(self)
-                }
+            if let Some(pos) = self.expn_info_shorthands.get(&expn_id).cloned() {
+                TAG_EXPANSION_INFO_SHORTHAND.encode(self)?;
+                pos.encode(self)
             } else {
-                TAG_NO_EXPANSION_INFO.encode(self)
+                TAG_EXPANSION_INFO_INLINE.encode(self)?;
+                let pos = AbsoluteBytePos::new(self.position());
+                self.expn_info_shorthands.insert(expn_id, pos);
+                expn_info.encode(self)
             }
         }
     }