Backport completions are at typer (#16558)

Author: dwijnand

compiler/src/dotty/tools/dotc/interactive/Completion.scala

@@ -11,6 +11,7 @@ import dotty.tools.dotc.core.Flags._
 import dotty.tools.dotc.core.Names.{Name, TermName}
 import dotty.tools.dotc.core.NameKinds.SimpleNameKind
 import dotty.tools.dotc.core.NameOps._
+import dotty.tools.dotc.core.Phases
 import dotty.tools.dotc.core.Scopes._
 import dotty.tools.dotc.core.Symbols.{NoSymbol, Symbol, defn, newSymbol}
 import dotty.tools.dotc.core.StdNames.nme
@@ -45,7 +46,7 @@ object Completion {
    */
   def completions(pos: SourcePosition)(using Context): (Int, List[Completion]) = {
     val path = Interactive.pathTo(ctx.compilationUnit.tpdTree, pos.span)
-    computeCompletions(pos, path)(using Interactive.contextOfPath(path))
+    computeCompletions(pos, path)(using Interactive.contextOfPath(path).withPhase(Phases.typerPhase))
   }
 
   /**

compiler/test/dotty/tools/repl/TabcompleteTests.scala

@@ -228,4 +228,9 @@ class TabcompleteTests extends ReplTest {
       tabComplete(":d")
     )
   }
+
+  @Test def `i16551 typer phase for implicits` = initially {
+    val comp = tabComplete("BigInt(1).")
+    assertTrue(comp.distinct.nonEmpty)
+  }
 }