Rollup merge of #60579 - varkor:typaram-index, r=eddyb

Rename `ParamTy::idx` to `ParamTy::index`

This makes it consistent with `ParamConst` and `EarlyBoundRegion`.

Author: Centril

src/librustc/traits/error_reporting.rs

@@ -1453,7 +1453,7 @@ impl<'a, 'gcx, 'tcx> InferCtxt<'a, 'gcx, 'tcx> {
             fn tcx<'b>(&'b self) -> TyCtxt<'b, 'gcx, 'tcx> { self.infcx.tcx }
 
             fn fold_ty(&mut self, ty: Ty<'tcx>) -> Ty<'tcx> {
-                if let ty::Param(ty::ParamTy {name, ..}) = ty.sty {
+                if let ty::Param(ty::ParamTy {name, .. }) = ty.sty {
                     let infcx = self.infcx;
                     self.var_map.entry(ty).or_insert_with(||
                         infcx.next_ty_var(

src/librustc/traits/select.rs

@@ -3424,7 +3424,7 @@ impl<'cx, 'gcx, 'tcx> SelectionContext<'cx, 'gcx, 'tcx> {
                 let mut found = false;
                 for ty in field.walk() {
                     if let ty::Param(p) = ty.sty {
-                        ty_params.insert(p.idx as usize);
+                        ty_params.insert(p.index as usize);
                         found = true;
                     }
                 }

src/librustc/traits/util.rs

@@ -204,7 +204,7 @@ impl<'cx, 'gcx, 'tcx> Elaborator<'cx, 'gcx, 'tcx> {
                            },
 
                            Component::Param(p) => {
-                               let ty = tcx.mk_ty_param(p.idx, p.name);
+                               let ty = tcx.mk_ty_param(p.index, p.name);
                                Some(ty::Predicate::TypeOutlives(
                                    ty::Binder::dummy(ty::OutlivesPredicate(ty, r_min))))
                            },

src/librustc/ty/context.rs

@@ -2715,10 +2715,8 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
     }
 
     #[inline]
-    pub fn mk_ty_param(self,
-                       index: u32,
-                       name: InternedString) -> Ty<'tcx> {
-        self.mk_ty(Param(ParamTy { idx: index, name: name }))
+    pub fn mk_ty_param(self, index: u32, name: InternedString) -> Ty<'tcx> {
+        self.mk_ty(Param(ParamTy { index, name: name }))
     }
 
     #[inline]

src/librustc/ty/mod.rs

@@ -979,7 +979,7 @@ impl<'a, 'gcx, 'tcx> Generics {
                       param: &ParamTy,
                       tcx: TyCtxt<'a, 'gcx, 'tcx>)
                       -> &'tcx GenericParamDef {
-        if let Some(index) = param.idx.checked_sub(self.parent_count as u32) {
+        if let Some(index) = param.index.checked_sub(self.parent_count as u32) {
             let param = &self.params[index as usize];
             match param.kind {
                 GenericParamDefKind::Type { .. } => param,

src/librustc/ty/relate.rs

@@ -390,7 +390,7 @@ pub fn super_relate_tys<'a, 'gcx, 'tcx, R>(relation: &mut R,
         }
 
         (&ty::Param(ref a_p), &ty::Param(ref b_p))
-            if a_p.idx == b_p.idx =>
+            if a_p.index == b_p.index =>
         {
             Ok(a)
         }

src/librustc/ty/structural_impls.rs

@@ -240,7 +240,7 @@ impl fmt::Debug for Ty<'tcx> {
 
 impl fmt::Debug for ty::ParamTy {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        write!(f, "{}/#{}", self.name, self.idx)
+        write!(f, "{}/#{}", self.name, self.index)
     }
 }
 

src/librustc/ty/sty.rs

@@ -1111,13 +1111,13 @@ pub type CanonicalPolyFnSig<'tcx> = Canonical<'tcx, Binder<FnSig<'tcx>>>;
 #[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord,
          Hash, RustcEncodable, RustcDecodable, HashStable)]
 pub struct ParamTy {
-    pub idx: u32,
+    pub index: u32,
     pub name: InternedString,
 }
 
 impl<'a, 'gcx, 'tcx> ParamTy {
     pub fn new(index: u32, name: InternedString) -> ParamTy {
-        ParamTy { idx: index, name: name }
+        ParamTy { index, name: name }
     }
 
     pub fn for_self() -> ParamTy {
@@ -1129,14 +1129,14 @@ impl<'a, 'gcx, 'tcx> ParamTy {
     }
 
     pub fn to_ty(self, tcx: TyCtxt<'a, 'gcx, 'tcx>) -> Ty<'tcx> {
-        tcx.mk_ty_param(self.idx, self.name)
+        tcx.mk_ty_param(self.index, self.name)
     }
 
     pub fn is_self(&self) -> bool {
-        // FIXME(#50125): Ignoring `Self` with `idx != 0` might lead to weird behavior elsewhere,
+        // FIXME(#50125): Ignoring `Self` with `index != 0` might lead to weird behavior elsewhere,
         // but this should only be possible when using `-Z continue-parse-after-error` like
         // `compile-fail/issue-36638.rs`.
-        self.name == keywords::SelfUpper.name().as_str() && self.idx == 0
+        self.name == keywords::SelfUpper.name().as_str() && self.index == 0
     }
 }
 
@@ -1763,7 +1763,7 @@ impl<'a, 'gcx, 'tcx> TyS<'tcx> {
 
     pub fn is_param(&self, index: u32) -> bool {
         match self.sty {
-            ty::Param(ref data) => data.idx == index,
+            ty::Param(ref data) => data.index == index,
             _ => false,
         }
     }

src/librustc/ty/subst.rs

@@ -547,7 +547,7 @@ impl<'a, 'gcx, 'tcx> TypeFolder<'gcx, 'tcx> for SubstFolder<'a, 'gcx, 'tcx> {
 impl<'a, 'gcx, 'tcx> SubstFolder<'a, 'gcx, 'tcx> {
     fn ty_for_param(&self, p: ty::ParamTy, source_ty: Ty<'tcx>) -> Ty<'tcx> {
         // Look up the type in the substitutions. It really should be in there.
-        let opt_ty = self.substs.get(p.idx as usize).map(|k| k.unpack());
+        let opt_ty = self.substs.get(p.index as usize).map(|k| k.unpack());
         let ty = match opt_ty {
             Some(UnpackedKind::Type(ty)) => ty,
             Some(kind) => {
@@ -558,7 +558,7 @@ impl<'a, 'gcx, 'tcx> SubstFolder<'a, 'gcx, 'tcx> {
                      when substituting (root type={:?}) substs={:?}",
                     p,
                     source_ty,
-                    p.idx,
+                    p.index,
                     kind,
                     self.root_ty,
                     self.substs,
@@ -572,7 +572,7 @@ impl<'a, 'gcx, 'tcx> SubstFolder<'a, 'gcx, 'tcx> {
                      when substituting (root type={:?}) substs={:?}",
                     p,
                     source_ty,
-                    p.idx,
+                    p.index,
                     self.root_ty,
                     self.substs,
                 );

src/librustc_typeck/check/method/probe.rs

@@ -757,8 +757,7 @@ impl<'a, 'gcx, 'tcx> ProbeContext<'a, 'gcx, 'tcx> {
         });
     }
 
-    fn assemble_inherent_candidates_from_param(&mut self,
-                                               param_ty: ty::ParamTy) {
+    fn assemble_inherent_candidates_from_param(&mut self, param_ty: ty::ParamTy) {
         // FIXME -- Do we want to commit to this behavior for param bounds?
 
         let bounds = self.param_env