TyperState#mergeConstraintWith: use the correct context

smarter · smarter · commit be1b6a1417b6 · 2021-09-11T15:22:22.000+02:00
Previously, the code in the closure passed to `comparing` could have
been using the wrong context. I don't think this happened in practice so
far because comparingCtx was always equal to ctx but it will matter in the
next commit.
diff --git a/compiler/src/dotty/tools/dotc/core/TyperState.scala b/compiler/src/dotty/tools/dotc/core/TyperState.scala
@@ -192,7 +192,7 @@ class TyperState() {
 
     val comparingCtx = ctx.withTyperState(this)
 
-    comparing(typeComparer =>
+    inContext(comparingCtx)(comparing(typeComparer =>
       val other = that.constraint
       val res = other.domainLambdas.forall(tl =>
         // Integrate the type lambdas from `other`
@@ -219,7 +219,7 @@ class TyperState() {
           )
         )
       assert(res || ctx.reporter.errorsReported, i"cannot merge $constraint with $other.")
-    )(using comparingCtx)
+    ))
 
     for tl <- constraint.domainLambdas do
       if constraint.isRemovable(tl) then constraint = constraint.remove(tl)

Original file line number	Diff line number	Diff line change
`@@ -192,7 +192,7 @@ class TyperState() {`
`192`	`192`
`193`	`193`	`val comparingCtx = ctx.withTyperState(this)`
`194`	`194`
`195`		`- comparing(typeComparer =>`
	`195`	`+ inContext(comparingCtx)(comparing(typeComparer =>`
`196`	`196`	`val other = that.constraint`
`197`	`197`	`val res = other.domainLambdas.forall(tl =>`
`198`	`198`	// Integrate the type lambdas from `other`
`@@ -219,7 +219,7 @@ class TyperState() {`
`219`	`219`	`)`
`220`	`220`	`)`
`221`	`221`	`assert(res \|\| ctx.reporter.errorsReported, i"cannot merge $constraint with $other.")`
`222`		`- )(using comparingCtx)`
	`222`	`+ ))`
`223`	`223`
`224`	`224`	`for tl <- constraint.domainLambdas do`
`225`	`225`	`if constraint.isRemovable(tl) then constraint = constraint.remove(tl)`