From 1c19629e373e781523ffc41caa66315b1c705b47 Mon Sep 17 00:00:00 2001
From: Nicolas Stucki <nicolas.stucki@gmail.com>
Date: Mon, 27 Jul 2020 17:06:52 +0200
Subject: [PATCH 1/8] Move Staging phase after typer

---
 compiler/src/dotty/tools/dotc/Compiler.scala | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/compiler/src/dotty/tools/dotc/Compiler.scala b/compiler/src/dotty/tools/dotc/Compiler.scala
index 84e81801a495..ecbda7e157ca 100644
--- a/compiler/src/dotty/tools/dotc/Compiler.scala
+++ b/compiler/src/dotty/tools/dotc/Compiler.scala
@@ -38,10 +38,10 @@ class Compiler {
   protected def frontendPhases: List[List[Phase]] =
     List(new FrontEnd) ::           // Compiler frontend: scanner, parser, namer, typer
     List(new YCheckPositions) ::    // YCheck positions
-    List(new Staging) ::            // Check PCP, heal quoted types and expand macros
     List(new sbt.ExtractDependencies) :: // Sends information on classes' dependencies to sbt via callbacks
     List(new semanticdb.ExtractSemanticDB) :: // Extract info into .semanticdb files
     List(new PostTyper) ::          // Additional checks and cleanups after type checking
+    List(new Staging) ::            // Check PCP, heal quoted types and expand macros
     List(new sbt.ExtractAPI) ::     // Sends a representation of the API of classes to sbt via callbacks
     List(new SetRootTree) ::        // Set the `rootTreeOrProvider` on class symbols
     Nil

From 7d2c1cc9ef23bd9d1fab14706b263c8fdd4f8e49 Mon Sep 17 00:00:00 2001
From: Nicolas Stucki <nicolas.stucki@gmail.com>
Date: Mon, 27 Jul 2020 17:20:58 +0200
Subject: [PATCH 2/8] Detect all quotes in postyper

* Explicit
* Synthesized implicits
* Inlined
---
 compiler/src/dotty/tools/dotc/transform/PostTyper.scala  | 2 ++
 compiler/src/dotty/tools/dotc/typer/Inliner.scala        | 9 ++-------
 .../src/dotty/tools/dotc/typer/QuotesAndSplices.scala    | 3 ---
 compiler/src/dotty/tools/dotc/typer/Synthesizer.scala    | 2 --
 4 files changed, 4 insertions(+), 12 deletions(-)

diff --git a/compiler/src/dotty/tools/dotc/transform/PostTyper.scala b/compiler/src/dotty/tools/dotc/transform/PostTyper.scala
index ad14b9e7b1d7..84c98c74a815 100644
--- a/compiler/src/dotty/tools/dotc/transform/PostTyper.scala
+++ b/compiler/src/dotty/tools/dotc/transform/PostTyper.scala
@@ -269,6 +269,8 @@ class PostTyper extends MacroTransform with IdentityDenotTransformer { thisPhase
           val patterns1 = transform(patterns)
           cpy.UnApply(tree)(transform(fun), transform(implicits), patterns1)
         case tree: TypeApply =>
+          if tree.symbol.isQuote then
+            ctx.compilationUnit.needsStaging = true
           val tree1 @ TypeApply(fn, args) = normalizeTypeArgs(tree)
           args.foreach(checkInferredWellFormed)
           if (fn.symbol != defn.ChildAnnot.primaryConstructor)
diff --git a/compiler/src/dotty/tools/dotc/typer/Inliner.scala b/compiler/src/dotty/tools/dotc/typer/Inliner.scala
index 93d975d14ec5..304545fe7ac4 100644
--- a/compiler/src/dotty/tools/dotc/typer/Inliner.scala
+++ b/compiler/src/dotty/tools/dotc/typer/Inliner.scala
@@ -1192,7 +1192,7 @@ class Inliner(call: tpd.Tree, rhsToInline: tpd.Tree)(using Context) {
     }
 
     override def typedIdent(tree: untpd.Ident, pt: Type)(using Context): Tree =
-      checkStaging(tryInline(tree.asInstanceOf[tpd.Tree]) `orElse` super.typedIdent(tree, pt))
+      tryInline(tree.asInstanceOf[tpd.Tree]) `orElse` super.typedIdent(tree, pt)
 
     override def typedSelect(tree: untpd.Select, pt: Type)(using Context): Tree = {
       assert(tree.hasType, tree)
@@ -1204,14 +1204,9 @@ class Inliner(call: tpd.Tree, rhsToInline: tpd.Tree)(using Context) {
       else
         val res = resMaybeReduced
         ensureAccessible(res.tpe, tree.qualifier.isInstanceOf[untpd.Super], tree.sourcePos)
-        checkStaging(res)
+        res
     }
 
-    private def checkStaging(tree: Tree): tree.type =
-      if tree.symbol.isQuote then
-        ctx.compilationUnit.needsStaging = true
-      tree
-
     override def typedIf(tree: untpd.If, pt: Type)(using Context): Tree =
       typed(tree.cond, defn.BooleanType) match {
         case cond1 @ ConstantValue(b: Boolean) =>
diff --git a/compiler/src/dotty/tools/dotc/typer/QuotesAndSplices.scala b/compiler/src/dotty/tools/dotc/typer/QuotesAndSplices.scala
index 4f4d3f71b3aa..14a65f507aa6 100644
--- a/compiler/src/dotty/tools/dotc/typer/QuotesAndSplices.scala
+++ b/compiler/src/dotty/tools/dotc/typer/QuotesAndSplices.scala
@@ -40,7 +40,6 @@ trait QuotesAndSplices {
    */
   def typedQuote(tree: untpd.Quote, pt: Type)(using Context): Tree = {
     record("typedQuote")
-    ctx.compilationUnit.needsStaging = true
     tree.quoted match {
       case untpd.Splice(innerExpr) if tree.isTerm =>
         report.warning("Canceled splice directly inside a quote. '{ ${ XYZ } } is equivalent to XYZ.", tree.sourcePos)
@@ -68,7 +67,6 @@ trait QuotesAndSplices {
   /** Translate `${ t: Expr[T] }` into expression `t.splice` while tracking the quotation level in the context */
   def typedSplice(tree: untpd.Splice, pt: Type)(using Context): Tree = {
     record("typedSplice")
-    ctx.compilationUnit.needsStaging = true
     checkSpliceOutsideQuote(tree)
     tree.expr match {
       case untpd.Quote(innerExpr) if innerExpr.isTerm =>
@@ -147,7 +145,6 @@ trait QuotesAndSplices {
   /** Translate ${ t: Type[T] }` into type `t.splice` while tracking the quotation level in the context */
   def typedTypSplice(tree: untpd.TypSplice, pt: Type)(using Context): Tree = {
     record("typedTypSplice")
-    ctx.compilationUnit.needsStaging = true
     checkSpliceOutsideQuote(tree)
     tree.expr match {
       case untpd.Quote(innerType) if innerType.isType =>
diff --git a/compiler/src/dotty/tools/dotc/typer/Synthesizer.scala b/compiler/src/dotty/tools/dotc/typer/Synthesizer.scala
index cf434da334e2..80af11f2e72b 100644
--- a/compiler/src/dotty/tools/dotc/typer/Synthesizer.scala
+++ b/compiler/src/dotty/tools/dotc/typer/Synthesizer.scala
@@ -53,8 +53,6 @@ class Synthesizer(typer: Typer)(using @constructorOnly c: Context):
    */
   val synthesizedTypeTag: SpecialHandler = (formal, span) =>
     def quotedType(t: Type) =
-      if StagingContext.level == 0 then
-        ctx.compilationUnit.needsStaging = true // We will need to run ReifyQuotes
       val qctx = ctx.typer.inferImplicitArg(defn.QuoteContextClass.typeRef, span)
       qctx.tpe match
         case tpe: Implicits.SearchFailureType => report.error(tpe.msg, ctx.source.atSpan(span))

From 6c1edfad08fa93afb9941b95271916ac351a4ef9 Mon Sep 17 00:00:00 2001
From: Nicolas Stucki <nicolas.stucki@gmail.com>
Date: Mon, 27 Jul 2020 17:31:38 +0200
Subject: [PATCH 3/8] Add quoted.Type.apply constructor

Just as `$t` is equivalent to `t.T`, `'[T]` is equivalent to `Type[T]`
---
 compiler/src/dotty/tools/dotc/ast/TreeInfo.scala             | 2 +-
 compiler/src/dotty/tools/dotc/core/Definitions.scala         | 2 +-
 .../src/dotty/tools/dotc/printing/DecompilerPrinter.scala    | 2 +-
 compiler/src/dotty/tools/dotc/printing/RefinedPrinter.scala  | 2 +-
 compiler/src/dotty/tools/dotc/transform/ReifyQuotes.scala    | 4 ++--
 compiler/src/dotty/tools/dotc/transform/Splicer.scala        | 4 ++--
 compiler/src/dotty/tools/dotc/transform/SymUtils.scala       | 2 +-
 compiler/src/dotty/tools/dotc/typer/Inliner.scala            | 2 +-
 compiler/src/dotty/tools/dotc/typer/QuotesAndSplices.scala   | 4 ++--
 compiler/src/dotty/tools/dotc/typer/Synthesizer.scala        | 2 +-
 .../src-bootstrapped/scala/internal/quoted/CompileTime.scala | 4 ----
 library/src-bootstrapped/scala/quoted/Type.scala             | 5 +++++
 12 files changed, 18 insertions(+), 17 deletions(-)

diff --git a/compiler/src/dotty/tools/dotc/ast/TreeInfo.scala b/compiler/src/dotty/tools/dotc/ast/TreeInfo.scala
index 67ba61d4a444..4a97e8273e17 100644
--- a/compiler/src/dotty/tools/dotc/ast/TreeInfo.scala
+++ b/compiler/src/dotty/tools/dotc/ast/TreeInfo.scala
@@ -397,7 +397,7 @@ trait TypedTreeInfo extends TreeInfo[Type] { self: Trees.Instance[Type] =>
     case New(_) | Closure(_, _, _) =>
       Pure
     case TypeApply(fn, _) =>
-      if (fn.symbol.is(Erased) || fn.symbol == defn.InternalQuoted_typeQuote || fn.symbol == defn.Predef_classOf) Pure else exprPurity(fn)
+      if (fn.symbol.is(Erased) || fn.symbol == defn.QuotedTypeModule_apply || fn.symbol == defn.Predef_classOf) Pure else exprPurity(fn)
     case Apply(fn, args) =>
       def isKnownPureOp(sym: Symbol) =
         sym.owner.isPrimitiveValueClass
diff --git a/compiler/src/dotty/tools/dotc/core/Definitions.scala b/compiler/src/dotty/tools/dotc/core/Definitions.scala
index 1f7b51bf78e7..1f8a5786aeb1 100644
--- a/compiler/src/dotty/tools/dotc/core/Definitions.scala
+++ b/compiler/src/dotty/tools/dotc/core/Definitions.scala
@@ -693,7 +693,6 @@ class Definitions {
     @tu lazy val InternalQuoted_exprQuote  : Symbol = InternalQuotedModule.requiredMethod("exprQuote")
     @tu lazy val InternalQuoted_exprSplice : Symbol = InternalQuotedModule.requiredMethod("exprSplice")
     @tu lazy val InternalQuoted_exprNestedSplice : Symbol = InternalQuotedModule.requiredMethod("exprNestedSplice")
-    @tu lazy val InternalQuoted_typeQuote  : Symbol = InternalQuotedModule.requiredMethod("typeQuote")
     @tu lazy val InternalQuoted_QuoteTypeTagAnnot: ClassSymbol = InternalQuotedModule.requiredClass("quoteTypeTag")
 
   @tu lazy val InternalQuotedMatcher: Symbol = requiredModule("scala.internal.quoted.Matcher")
@@ -713,6 +712,7 @@ class Definitions {
     @tu lazy val QuotedType_splice: Symbol = QuotedTypeClass.requiredType(tpnme.spliceType)
 
   @tu lazy val QuotedTypeModule: Symbol = QuotedTypeClass.companionModule
+    @tu lazy val QuotedTypeModule_apply: Symbol = QuotedTypeModule.requiredMethod("apply")
 
   @tu lazy val TastyReflectionClass: ClassSymbol = requiredClass("scala.tasty.Reflection")
 
diff --git a/compiler/src/dotty/tools/dotc/printing/DecompilerPrinter.scala b/compiler/src/dotty/tools/dotc/printing/DecompilerPrinter.scala
index d2ac15493864..d5c75502ceee 100644
--- a/compiler/src/dotty/tools/dotc/printing/DecompilerPrinter.scala
+++ b/compiler/src/dotty/tools/dotc/printing/DecompilerPrinter.scala
@@ -75,6 +75,6 @@ class DecompilerPrinter(_ctx: Context) extends RefinedPrinter(_ctx) {
 
   override protected def typeApplyText[T >: Untyped](tree: TypeApply[T]): Text =
     if (tree.symbol eq defn.InternalQuoted_exprQuote) "'"
-    else if (tree.symbol eq defn.InternalQuoted_typeQuote) "'[" ~ toTextGlobal(tree.args, ", ") ~ "]"
+    else if (tree.symbol eq defn.QuotedTypeModule_apply) "'[" ~ toTextGlobal(tree.args, ", ") ~ "]"
     else super.typeApplyText(tree)
 }
diff --git a/compiler/src/dotty/tools/dotc/printing/RefinedPrinter.scala b/compiler/src/dotty/tools/dotc/printing/RefinedPrinter.scala
index 147a959dbedf..e36504b54cbc 100644
--- a/compiler/src/dotty/tools/dotc/printing/RefinedPrinter.scala
+++ b/compiler/src/dotty/tools/dotc/printing/RefinedPrinter.scala
@@ -266,7 +266,7 @@ class RefinedPrinter(_ctx: Context) extends PlainPrinter(_ctx) {
     ("{" ~ toText(trees, "\n") ~ "}").close
 
   protected def typeApplyText[T >: Untyped](tree: TypeApply[T]): Text = {
-    val isQuote = !printDebug && tree.fun.hasType && tree.fun.symbol == defn.InternalQuoted_typeQuote
+    val isQuote = !printDebug && tree.fun.hasType && tree.fun.symbol == defn.QuotedTypeModule_apply
     val (open, close) = if (isQuote) (keywordStr("'["), keywordStr("]")) else ("[", "]")
     val funText = toTextLocal(tree.fun).provided(!isQuote)
     tree.fun match {
diff --git a/compiler/src/dotty/tools/dotc/transform/ReifyQuotes.scala b/compiler/src/dotty/tools/dotc/transform/ReifyQuotes.scala
index 0b2d1cf03520..9bc1e4bcb5ea 100644
--- a/compiler/src/dotty/tools/dotc/transform/ReifyQuotes.scala
+++ b/compiler/src/dotty/tools/dotc/transform/ReifyQuotes.scala
@@ -127,7 +127,7 @@ class ReifyQuotes extends MacroTransform {
      *  core and splices as arguments.
      */
     override protected def transformQuotation(body: Tree, quote: Tree)(using Context): Tree = {
-      val isType = quote.symbol eq defn.InternalQuoted_typeQuote
+      val isType = quote.symbol eq defn.QuotedTypeModule_apply
       if (level > 0) {
         val body1 = nested(isQuote = true).transform(body)(using quoteContext)
         super.transformQuotation(body1, quote)
@@ -364,7 +364,7 @@ class ReifyQuotes extends MacroTransform {
         transform(tree)(using ctx.withSource(tree.source))
       else reporting.trace(i"Reifier.transform $tree at $level", show = true) {
         tree match {
-          case Apply(Select(TypeApply(fn, (body: RefTree) :: Nil), _), _) if fn.symbol == defn.InternalQuoted_typeQuote && isCaptured(body.symbol, level + 1) =>
+          case Apply(Select(TypeApply(fn, (body: RefTree) :: Nil), _), _) if fn.symbol == defn.QuotedTypeModule_apply && isCaptured(body.symbol, level + 1) =>
             // Optimization: avoid the full conversion when capturing `x`
             // in '{ x } to '{ ${x$1} } and go directly to `x$1`
             capturers(body.symbol)(body)
diff --git a/compiler/src/dotty/tools/dotc/transform/Splicer.scala b/compiler/src/dotty/tools/dotc/transform/Splicer.scala
index 76b1f6141707..c9d72de172bf 100644
--- a/compiler/src/dotty/tools/dotc/transform/Splicer.scala
+++ b/compiler/src/dotty/tools/dotc/transform/Splicer.scala
@@ -141,7 +141,7 @@ object Splicer {
         case Apply(Select(Apply(fn, quoted :: Nil), nme.apply), _) if fn.symbol == defn.InternalQuoted_exprQuote =>
           // OK
 
-        case TypeApply(fn, quoted :: Nil) if fn.symbol == defn.InternalQuoted_typeQuote =>
+        case TypeApply(fn, quoted :: Nil) if fn.symbol == defn.QuotedTypeModule_apply =>
           // OK
 
         case Literal(Constant(value)) =>
@@ -231,7 +231,7 @@ object Splicer {
         }
         interpretQuote(quoted1)
 
-      case Apply(Select(TypeApply(fn, quoted :: Nil), _), _) if fn.symbol == defn.InternalQuoted_typeQuote =>
+      case Apply(Select(TypeApply(fn, quoted :: Nil), _), _) if fn.symbol == defn.QuotedTypeModule_apply =>
         interpretTypeQuote(quoted)
 
       case Literal(Constant(value)) =>
diff --git a/compiler/src/dotty/tools/dotc/transform/SymUtils.scala b/compiler/src/dotty/tools/dotc/transform/SymUtils.scala
index 28395538d825..c9373622bf91 100644
--- a/compiler/src/dotty/tools/dotc/transform/SymUtils.scala
+++ b/compiler/src/dotty/tools/dotc/transform/SymUtils.scala
@@ -203,7 +203,7 @@ object SymUtils {
 
   /** Is symbol a quote operation? */
   def isQuote(using Context): Boolean =
-    self == defn.InternalQuoted_exprQuote || self == defn.InternalQuoted_typeQuote
+    self == defn.InternalQuoted_exprQuote || self == defn.QuotedTypeModule_apply
 
   /** Is symbol a term splice operation? */
   def isExprSplice(using Context): Boolean =
diff --git a/compiler/src/dotty/tools/dotc/typer/Inliner.scala b/compiler/src/dotty/tools/dotc/typer/Inliner.scala
index 304545fe7ac4..0bb431a1479a 100644
--- a/compiler/src/dotty/tools/dotc/typer/Inliner.scala
+++ b/compiler/src/dotty/tools/dotc/typer/Inliner.scala
@@ -528,7 +528,7 @@ class Inliner(call: tpd.Tree, rhsToInline: tpd.Tree)(using Context) {
       case New(_) | Closure(_, _, _) =>
         true
       case TypeApply(fn, _) =>
-        if (fn.symbol.is(Erased) || fn.symbol == defn.InternalQuoted_typeQuote) true else apply(fn)
+        if (fn.symbol.is(Erased) || fn.symbol == defn.QuotedTypeModule_apply) true else apply(fn)
       case Apply(fn, args) =>
         def isKnownPureOp(sym: Symbol) =
           sym.owner.isPrimitiveValueClass
diff --git a/compiler/src/dotty/tools/dotc/typer/QuotesAndSplices.scala b/compiler/src/dotty/tools/dotc/typer/QuotesAndSplices.scala
index 14a65f507aa6..122d77056ece 100644
--- a/compiler/src/dotty/tools/dotc/typer/QuotesAndSplices.scala
+++ b/compiler/src/dotty/tools/dotc/typer/QuotesAndSplices.scala
@@ -58,7 +58,7 @@ trait QuotesAndSplices {
       if ctx.mode.is(Mode.Pattern) then
         typedQuotePattern(tree, pt, qctx)
       else if (tree.quoted.isType)
-        typedTypeApply(untpd.TypeApply(untpd.ref(defn.InternalQuoted_typeQuote.termRef), tree.quoted :: Nil), pt)(using quoteContext).select(nme.apply).appliedTo(qctx)
+        typedTypeApply(untpd.TypeApply(untpd.ref(defn.QuotedTypeModule_apply.termRef), tree.quoted :: Nil), pt)(using quoteContext).select(nme.apply).appliedTo(qctx)
       else
         typedApply(untpd.Apply(untpd.ref(defn.InternalQuoted_exprQuote.termRef), tree.quoted), pt)(using pushQuoteContext(qctx)).select(nme.apply).appliedTo(qctx)
     tree1.withSpan(tree.span)
@@ -439,7 +439,7 @@ trait QuotesAndSplices {
     val quoteClass = if (tree.quoted.isTerm) defn.QuotedExprClass else defn.QuotedTypeClass
     val quotedPattern =
       if (tree.quoted.isTerm) ref(defn.InternalQuoted_exprQuote.termRef).appliedToType(defn.AnyType).appliedTo(shape).select(nme.apply).appliedTo(qctx)
-      else ref(defn.InternalQuoted_typeQuote.termRef).appliedToTypeTree(shape).select(nme.apply).appliedTo(qctx)
+      else ref(defn.QuotedTypeModule_apply.termRef).appliedToTypeTree(shape).select(nme.apply).appliedTo(qctx)
     UnApply(
       fun = ref(unapplySym.termRef).appliedToTypeTrees(typeBindingsTuple :: TypeTree(patType) :: Nil),
       implicits = quotedPattern :: Literal(Constant(typeBindings.nonEmpty)) :: qctx :: Nil,
diff --git a/compiler/src/dotty/tools/dotc/typer/Synthesizer.scala b/compiler/src/dotty/tools/dotc/typer/Synthesizer.scala
index 80af11f2e72b..1215df0a97a3 100644
--- a/compiler/src/dotty/tools/dotc/typer/Synthesizer.scala
+++ b/compiler/src/dotty/tools/dotc/typer/Synthesizer.scala
@@ -57,7 +57,7 @@ class Synthesizer(typer: Typer)(using @constructorOnly c: Context):
       qctx.tpe match
         case tpe: Implicits.SearchFailureType => report.error(tpe.msg, ctx.source.atSpan(span))
         case _ =>
-      ref(defn.InternalQuoted_typeQuote).appliedToType(t).select(nme.apply).appliedTo(qctx)
+      ref(defn.QuotedTypeModule_apply).appliedToType(t).select(nme.apply).appliedTo(qctx)
     formal.argInfos match
       case arg :: Nil =>
         val deepDealias = new TypeMap:
diff --git a/library/src-bootstrapped/scala/internal/quoted/CompileTime.scala b/library/src-bootstrapped/scala/internal/quoted/CompileTime.scala
index 4891d3cbf8c8..e6e6972481d5 100644
--- a/library/src-bootstrapped/scala/internal/quoted/CompileTime.scala
+++ b/library/src-bootstrapped/scala/internal/quoted/CompileTime.scala
@@ -20,10 +20,6 @@ object CompileTime {
   @compileTimeOnly("Illegal reference to `scala.internal.quoted.CompileTime.exprNestedSplice`")
   def exprNestedSplice[T](ctx: QuoteContext)(x: ctx.Nested ?=> Expr[T]): T = ???
 
-  /** A type quote is desugared by the compiler into a call to this method */
-  @compileTimeOnly("Illegal reference to `scala.internal.quoted.CompileTime.typeQuote`")
-  def typeQuote[T <: AnyKind]: QuoteContext ?=> Type[T] = ???
-
   /** Artifact of pickled type splices
    *
    *  During quote reification a quote `'{ ... F[$t] ... }` will be transformed into
diff --git a/library/src-bootstrapped/scala/quoted/Type.scala b/library/src-bootstrapped/scala/quoted/Type.scala
index 4a25af61f543..7b5b097954c8 100644
--- a/library/src-bootstrapped/scala/quoted/Type.scala
+++ b/library/src-bootstrapped/scala/quoted/Type.scala
@@ -1,5 +1,6 @@
 package scala.quoted
 
+import scala.annotation.compileTimeOnly
 import scala.quoted.show.SyntaxHighlight
 
 /** Quoted type (or kind) `T` */
@@ -22,6 +23,10 @@ abstract class Type[X <: AnyKind] private[scala] {
 /** Some basic type tags, currently incomplete */
 object Type {
 
+  /** Return a quoted.Type with the given type */
+  @compileTimeOnly("Reference to `scala.quoted.Type.apply` was not handled by ReifyQuotes")
+  def apply[T <: AnyKind]: QuoteContext ?=> Type[T] = ???
+
   def UnitTag: QuoteContext ?=> Type[Unit] =
     qctx.tasty.defn.UnitType.seal.asInstanceOf[quoted.Type[Unit]]
 

From cc00cbbc3fcf6e20b1528845d71bee09b24097c7 Mon Sep 17 00:00:00 2001
From: Nicolas Stucki <nicolas.stucki@gmail.com>
Date: Mon, 27 Jul 2020 18:03:08 +0200
Subject: [PATCH 4/8] Simplify synthetization of scala.quoted.Type

---
 .../dotty/tools/dotc/typer/Synthesizer.scala  | 21 +++++++------------
 1 file changed, 8 insertions(+), 13 deletions(-)

diff --git a/compiler/src/dotty/tools/dotc/typer/Synthesizer.scala b/compiler/src/dotty/tools/dotc/typer/Synthesizer.scala
index 1215df0a97a3..f1262cb6a160 100644
--- a/compiler/src/dotty/tools/dotc/typer/Synthesizer.scala
+++ b/compiler/src/dotty/tools/dotc/typer/Synthesizer.scala
@@ -48,23 +48,18 @@ class Synthesizer(typer: Typer)(using @constructorOnly c: Context):
       case _ => EmptyTree
   end synthesizedClassTag
 
-  /** Synthesize the tree for `'[T]` for an implicit `scala.quoted.Type[T]`.
+  /** Synthesize the tree for `scala.quoted.Type[T]` for an implicit `scala.quoted.Type[T]`.
    *  `T` is deeply dealiased to avoid references to local type aliases.
    */
   val synthesizedTypeTag: SpecialHandler = (formal, span) =>
-    def quotedType(t: Type) =
-      val qctx = ctx.typer.inferImplicitArg(defn.QuoteContextClass.typeRef, span)
-      qctx.tpe match
-        case tpe: Implicits.SearchFailureType => report.error(tpe.msg, ctx.source.atSpan(span))
-        case _ =>
-      ref(defn.QuotedTypeModule_apply).appliedToType(t).select(nme.apply).appliedTo(qctx)
-    formal.argInfos match
-      case arg :: Nil =>
-        val deepDealias = new TypeMap:
-          def apply(tp: Type): Type = mapOver(tp.dealias)
-        quotedType(deepDealias(arg))
+    val qctx = ctx.typer.inferImplicitArg(defn.QuoteContextClass.typeRef, span)
+    qctx.tpe match
+      case tpe: Implicits.SearchFailureType => report.error(tpe.msg, ctx.source.atSpan(span))
       case _ =>
-        EmptyTree
+    val deepDealias = new TypeMap:
+      def apply(tp: Type): Type = mapOver(tp.dealias)
+    val t = deepDealias(formal.select(tpnme.spliceType))
+    ref(defn.QuotedTypeModule_apply).appliedToType(t).select(nme.apply).appliedTo(qctx)
   end synthesizedTypeTag
 
   val synthesizedTupleFunction: SpecialHandler = (formal, span) =>

From 8fdadea4768868083607add3336d6aba1e39811e Mon Sep 17 00:00:00 2001
From: Nicolas Stucki <nicolas.stucki@gmail.com>
Date: Mon, 27 Jul 2020 18:14:45 +0200
Subject: [PATCH 5/8] Update test output

---
 tests/run-staging/quote-nested-4.check | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tests/run-staging/quote-nested-4.check b/tests/run-staging/quote-nested-4.check
index ebfd27eb5652..ca8eaa483f2f 100644
--- a/tests/run-staging/quote-nested-4.check
+++ b/tests/run-staging/quote-nested-4.check
@@ -1,5 +1,5 @@
 ((qctx: scala.quoted.QuoteContext) ?=> {
-  val t: scala.quoted.Type[scala.Predef.String] = scala.internal.quoted.CompileTime.typeQuote[scala.Predef.String].apply(using qctx)
+  val t: scala.quoted.Type[scala.Predef.String] = scala.quoted.Type.apply[scala.Predef.String].apply(using qctx)
 
   (t: scala.quoted.Type[scala.Predef.String])
 })

From 013b1e0146fb04ded51df11efaf4fb780ef9888b Mon Sep 17 00:00:00 2001
From: Nicolas Stucki <nicolas.stucki@gmail.com>
Date: Mon, 27 Jul 2020 18:41:43 +0200
Subject: [PATCH 6/8] Simplify printing of scala.quoted.Type.apply

---
 .../dotty/tools/dotc/printing/DecompilerPrinter.scala  |  1 -
 .../src/dotty/tools/dotc/printing/RefinedPrinter.scala | 10 ++++------
 2 files changed, 4 insertions(+), 7 deletions(-)

diff --git a/compiler/src/dotty/tools/dotc/printing/DecompilerPrinter.scala b/compiler/src/dotty/tools/dotc/printing/DecompilerPrinter.scala
index d5c75502ceee..261fd0aa637d 100644
--- a/compiler/src/dotty/tools/dotc/printing/DecompilerPrinter.scala
+++ b/compiler/src/dotty/tools/dotc/printing/DecompilerPrinter.scala
@@ -75,6 +75,5 @@ class DecompilerPrinter(_ctx: Context) extends RefinedPrinter(_ctx) {
 
   override protected def typeApplyText[T >: Untyped](tree: TypeApply[T]): Text =
     if (tree.symbol eq defn.InternalQuoted_exprQuote) "'"
-    else if (tree.symbol eq defn.QuotedTypeModule_apply) "'[" ~ toTextGlobal(tree.args, ", ") ~ "]"
     else super.typeApplyText(tree)
 }
diff --git a/compiler/src/dotty/tools/dotc/printing/RefinedPrinter.scala b/compiler/src/dotty/tools/dotc/printing/RefinedPrinter.scala
index e36504b54cbc..ca4b217c5f35 100644
--- a/compiler/src/dotty/tools/dotc/printing/RefinedPrinter.scala
+++ b/compiler/src/dotty/tools/dotc/printing/RefinedPrinter.scala
@@ -267,13 +267,12 @@ class RefinedPrinter(_ctx: Context) extends PlainPrinter(_ctx) {
 
   protected def typeApplyText[T >: Untyped](tree: TypeApply[T]): Text = {
     val isQuote = !printDebug && tree.fun.hasType && tree.fun.symbol == defn.QuotedTypeModule_apply
-    val (open, close) = if (isQuote) (keywordStr("'["), keywordStr("]")) else ("[", "]")
-    val funText = toTextLocal(tree.fun).provided(!isQuote)
+    val funText = toTextLocal(tree.fun)
     tree.fun match {
       case Select(New(tpt), nme.CONSTRUCTOR) if tpt.typeOpt.dealias.isInstanceOf[AppliedType] =>
         funText  // type was already printed by toText(new)
       case _ =>
-        funText ~ open ~ toTextGlobal(tree.args, ", ") ~ close
+        funText ~ "[" ~ toTextGlobal(tree.args, ", ") ~ "]"
     }
   }
 
@@ -632,9 +631,8 @@ class RefinedPrinter(_ctx: Context) extends PlainPrinter(_ctx) {
         }
       case Number(digits, kind) =>
         digits
-      case Quote(tree) =>
-        if (tree.isType) keywordStr("'[") ~ toTextGlobal(dropBlock(tree)) ~ keywordStr("]")
-        else keywordStr("'{") ~ toTextGlobal(dropBlock(tree)) ~ keywordStr("}")
+      case Quote(tree) if tree.isTerm =>
+        keywordStr("'{") ~ toTextGlobal(dropBlock(tree)) ~ keywordStr("}")
       case Splice(tree) =>
         keywordStr("${") ~ toTextGlobal(dropBlock(tree)) ~ keywordStr("}")
       case TypSplice(tree) =>

From 50691827b5274242db94d5a9315442772bd48963 Mon Sep 17 00:00:00 2001
From: Nicolas Stucki <nicolas.stucki@gmail.com>
Date: Tue, 28 Jul 2020 15:19:47 +0200
Subject: [PATCH 7/8] Simplify quoted.Type implicit search

Now it is a plain `given` definition and follows the normal implicit resulution rules.
Dealiasing of local inconsitent type aliases references are handled by `PCPCheckAndHeal`
before healing is atempted.
---
 .../tools/dotc/transform/PCPCheckAndHeal.scala    |  6 ++++--
 .../src/dotty/tools/dotc/typer/Synthesizer.scala  | 15 ---------------
 library/src-bootstrapped/scala/quoted/Type.scala  |  2 +-
 tests/run-macros/i7048/Lib_1.scala                |  2 +-
 4 files changed, 6 insertions(+), 19 deletions(-)

diff --git a/compiler/src/dotty/tools/dotc/transform/PCPCheckAndHeal.scala b/compiler/src/dotty/tools/dotc/transform/PCPCheckAndHeal.scala
index 688e48971b40..f9499c6b4715 100644
--- a/compiler/src/dotty/tools/dotc/transform/PCPCheckAndHeal.scala
+++ b/compiler/src/dotty/tools/dotc/transform/PCPCheckAndHeal.scala
@@ -175,8 +175,10 @@ class PCPCheckAndHeal(@constructorOnly ictx: Context) extends TreeMapWithStages(
       tp match
         case tp: TypeRef =>
           tp.prefix match
-            case NoPrefix if level > levelOf(tp.symbol) =>
-              tryHeal(tp.symbol, tp, pos)
+            case NoPrefix if level > levelOf(tp.symbol) && !tp.typeSymbol.hasAnnotation(defn.InternalQuoted_QuoteTypeTagAnnot) =>
+              val tp1 = tp.dealias
+              if tp1 != tp then apply(tp1)
+              else tryHeal(tp.symbol, tp, pos)
             case prefix: ThisType if !tp.symbol.isStatic && level > levelOf(prefix.cls) =>
               tryHeal(tp.symbol, tp, pos)
             case prefix: TermRef if tp.symbol.isTypeSplice =>
diff --git a/compiler/src/dotty/tools/dotc/typer/Synthesizer.scala b/compiler/src/dotty/tools/dotc/typer/Synthesizer.scala
index f1262cb6a160..4f000eb33dec 100644
--- a/compiler/src/dotty/tools/dotc/typer/Synthesizer.scala
+++ b/compiler/src/dotty/tools/dotc/typer/Synthesizer.scala
@@ -48,20 +48,6 @@ class Synthesizer(typer: Typer)(using @constructorOnly c: Context):
       case _ => EmptyTree
   end synthesizedClassTag
 
-  /** Synthesize the tree for `scala.quoted.Type[T]` for an implicit `scala.quoted.Type[T]`.
-   *  `T` is deeply dealiased to avoid references to local type aliases.
-   */
-  val synthesizedTypeTag: SpecialHandler = (formal, span) =>
-    val qctx = ctx.typer.inferImplicitArg(defn.QuoteContextClass.typeRef, span)
-    qctx.tpe match
-      case tpe: Implicits.SearchFailureType => report.error(tpe.msg, ctx.source.atSpan(span))
-      case _ =>
-    val deepDealias = new TypeMap:
-      def apply(tp: Type): Type = mapOver(tp.dealias)
-    val t = deepDealias(formal.select(tpnme.spliceType))
-    ref(defn.QuotedTypeModule_apply).appliedToType(t).select(nme.apply).appliedTo(qctx)
-  end synthesizedTypeTag
-
   val synthesizedTupleFunction: SpecialHandler = (formal, span) =>
     formal match
       case AppliedType(_, funArgs @ fun :: tupled :: Nil) =>
@@ -391,7 +377,6 @@ class Synthesizer(typer: Typer)(using @constructorOnly c: Context):
 
   val specialHandlers = List(
     defn.ClassTagClass        -> synthesizedClassTag,
-    defn.QuotedTypeClass      -> synthesizedTypeTag,
     defn.EqlClass             -> synthesizedEql,
     defn.TupledFunctionClass  -> synthesizedTupleFunction,
     defn.ValueOfClass         -> synthesizedValueOf,
diff --git a/library/src-bootstrapped/scala/quoted/Type.scala b/library/src-bootstrapped/scala/quoted/Type.scala
index 7b5b097954c8..7f9dacba7adf 100644
--- a/library/src-bootstrapped/scala/quoted/Type.scala
+++ b/library/src-bootstrapped/scala/quoted/Type.scala
@@ -25,7 +25,7 @@ object Type {
 
   /** Return a quoted.Type with the given type */
   @compileTimeOnly("Reference to `scala.quoted.Type.apply` was not handled by ReifyQuotes")
-  def apply[T <: AnyKind]: QuoteContext ?=> Type[T] = ???
+  given apply[T <: AnyKind] as (QuoteContext ?=> Type[T]) = ???
 
   def UnitTag: QuoteContext ?=> Type[Unit] =
     qctx.tasty.defn.UnitType.seal.asInstanceOf[quoted.Type[Unit]]
diff --git a/tests/run-macros/i7048/Lib_1.scala b/tests/run-macros/i7048/Lib_1.scala
index 2e38f9de1331..b2b0fc70f6c8 100644
--- a/tests/run-macros/i7048/Lib_1.scala
+++ b/tests/run-macros/i7048/Lib_1.scala
@@ -12,7 +12,7 @@ given [U] as IsExpr[Expr[U]] = new IsExpr[Expr[U]] {
 
 def f(x: Any): String = x.toString
 
-def g[T](x: T)(using e: IsExpr[T], tu: Type[e.Underlying]): QuoteContext ?=> Expr[String] = {
+def g[T](x: T)(using e: IsExpr[T])(using tu: Type[e.Underlying]): QuoteContext ?=> Expr[String] = {
   val underlying: Expr[e.Underlying] = e.toExpr(x)
   '{f($underlying)}
 }

From 7c4fa0c6412677651fd319e892c4c3f633be1517 Mon Sep 17 00:00:00 2001
From: Nicolas Stucki <nicolas.stucki@gmail.com>
Date: Wed, 29 Jul 2020 09:40:37 +0200
Subject: [PATCH 8/8] Remove dead code

---
 compiler/src/dotty/tools/dotc/printing/RefinedPrinter.scala | 1 -
 1 file changed, 1 deletion(-)

diff --git a/compiler/src/dotty/tools/dotc/printing/RefinedPrinter.scala b/compiler/src/dotty/tools/dotc/printing/RefinedPrinter.scala
index ca4b217c5f35..94c64a03e872 100644
--- a/compiler/src/dotty/tools/dotc/printing/RefinedPrinter.scala
+++ b/compiler/src/dotty/tools/dotc/printing/RefinedPrinter.scala
@@ -266,7 +266,6 @@ class RefinedPrinter(_ctx: Context) extends PlainPrinter(_ctx) {
     ("{" ~ toText(trees, "\n") ~ "}").close
 
   protected def typeApplyText[T >: Untyped](tree: TypeApply[T]): Text = {
-    val isQuote = !printDebug && tree.fun.hasType && tree.fun.symbol == defn.QuotedTypeModule_apply
     val funText = toTextLocal(tree.fun)
     tree.fun match {
       case Select(New(tpt), nme.CONSTRUCTOR) if tpt.typeOpt.dealias.isInstanceOf[AppliedType] =>