Inlined try block breaks pickling tests

[OlivierBlanvillain]

class Foo {
  inline def foo: Int = try { 1 } finally println("Hello")
  foo
}

$ dotc tests/allan/Test.scala -Ytest-pickler 
exception occurred while compiling tests/allan/Test.scala
Exception in thread "main" class dotty.tools.dotc.reporting.diagnostic.messages$Error at ?: pickling difference for class Foo in tests/allan/Test.scala, for details:
                   |
                   |  diff before-pickling.txt after-pickling.txt
	at dotty.tools.dotc.reporting.Reporting.error(Reporter.scala:88)
	at dotty.tools.dotc.transform.Pickler.testSame(Pickler.scala:107)
	at dotty.tools.dotc.transform.Pickler.testUnpickler$$anonfun$4(Pickler.scala:99)
	at scala.compat.java8.JProcedure1.apply(JProcedure1.java:18)
	at scala.compat.java8.JProcedure1.apply(JProcedure1.java:10)
	at scala.collection.TraversableLike$WithFilter.$anonfun$foreach$1(TraversableLike.scala:789)
	at scala.collection.mutable.HashMap.$anonfun$foreach$1(HashMap.scala:138)
	at scala.collection.mutable.HashTable.foreachEntry(HashTable.scala:236)
	at scala.collection.mutable.HashTable.foreachEntry$(HashTable.scala:229)
	at scala.collection.mutable.HashMap.foreachEntry(HashMap.scala:40)
	at scala.collection.mutable.HashMap.foreach(HashMap.scala:138)
	at scala.collection.TraversableLike$WithFilter.foreach(TraversableLike.scala:788)
	at dotty.tools.dotc.transform.Pickler.testUnpickler(Pickler.scala:100)
	at dotty.tools.dotc.transform.Pickler.runOn(Pickler.scala:83)
	at dotty.tools.dotc.Run.runPhases$4$$anonfun$4(Run.scala:123)
	at scala.compat.java8.JProcedure1.apply(JProcedure1.java:18)
	at scala.compat.java8.JProcedure1.apply(JProcedure1.java:10)
	at scala.collection.IndexedSeqOptimized.foreach(IndexedSeqOptimized.scala:32)
	at scala.collection.IndexedSeqOptimized.foreach$(IndexedSeqOptimized.scala:29)
	at scala.collection.mutable.ArrayOps$ofRef.foreach(ArrayOps.scala:191)
	at dotty.tools.dotc.Run.runPhases$5(Run.scala:136)
	at dotty.tools.dotc.Run.compileUnits$$anonfun$1(Run.scala:141)
	at scala.compat.java8.JFunction0$mcV$sp.apply(JFunction0$mcV$sp.java:12)
	at dotty.tools.dotc.util.Stats$.maybeMonitored(Stats.scala:88)
	at dotty.tools.dotc.Run.compileUnits(Run.scala:143)
	at dotty.tools.dotc.Run.compileSources(Run.scala:94)
	at dotty.tools.dotc.Run.compile(Run.scala:78)
	at dotty.tools.dotc.Driver.doCompile(Driver.scala:29)
	at dotty.tools.dotc.Driver.process(Driver.scala:127)
	at dotty.tools.dotc.Driver.process(Driver.scala:96)
	at dotty.tools.dotc.Driver.process(Driver.scala:108)
	at dotty.tools.dotc.Driver.main(Driver.scala:135)
	at dotty.tools.dotc.Main.main(Main.scala

[odersky]

I would classify pickling errors in quoting, if they manifest themselves as differences before and after pickling.

[nicolasstucki]

Decompiling the class shows that the inlined call to foo has a catch/case instead of a finally.
The current encoding for it is ambiguous as we have no way to determine if we need to read66:SHAREDterm 42 as a case or a finally (reading the cases).

    62:         TRY(4)
    64:           SHAREDterm 38
    66:           SHAREDterm 42

================================================================================
./Foo.class
--------------------------------------------------------------------------------
package <empty> {
  class Foo() extends Object() {
    @(try
      {
        1
      }
     finally println("Hello")) inline def foo: Int =
      try
        {
          1
        }
       finally println("Hello")
    /* inlined from Foo*/
      {
        try
          {
            1
          }
         catch
          {
            case println => "Hello"
          }
      }
  }
}
--------------------------------------------------------------------------------
Names:
   0: ASTs
   1: <empty>
   2: Foo
   3: <init>
   4: java
   5: lang
   6: java[Qualified . lang]
   7: Object
   8: java[Qualified . lang][Qualified . Object]
   9: <init>[Signed Signature(List(),java.lang.Object)]
  10: Unit
  11: scala
  12: foo
  13: Int
  14: println
  15: scala[Qualified . Unit]
  16: println[Signed Signature(List(java.lang.Object),scala.Unit)]
  17: Predef
  18: Hello
  19: SourceFile
  20: annotation
  21: scala[Qualified . annotation]
  22: internal
  23: scala[Qualified . annotation][Qualified . internal]
  24: scala[Qualified . annotation][Qualified . internal][Qualified . SourceFile]
  25: String
  26: java[Qualified . lang][Qualified . String]
  27: <init>[Signed Signature(List(java.lang.String),scala.annotation.internal.SourceFile)]
  28: Foo.scala
  29: Positions

Trees:
start = Addr(0), base = 227, current = Addr(0), end = Addr(83)
83 bytes of AST, base = Addr(0)

     0: PACKAGE(81)
     2:   TERMREFpkg 1 [<empty>]
     4:   TYPEDEF(77) 2 [Foo]
     7:     TEMPLATE(59)
     9:       APPLY(7)
    11:         SELECT 9 [<init>[Signed Signature(List(),java.lang.Object)]]
    13:           NEW
    14:             TYPEREF 7 [Object]
    16:               TERMREFpkg 6 [java[Qualified . lang]]
    18:       DEFDEF(7) 3 [<init>]
    21:         PARAMS(0)
    23:         TYPEREF 10 [Unit]
    25:           TERMREFpkg 11 [scala]
    27:       DEFDEF(24) 12 [foo]
    30:         IDENTtpt 13 [Int]
    32:           TYPEREF 13 [Int]
    34:             TERMREFpkg 11 [scala]
    36:         TRY(14)
    38:           BLOCK(2)
    40:             INTconst 1
    42:           APPLY(8)
    44:             TERMREF 16 [println[Signed Signature(List(java.lang.Object),scala.Unit)]]
    46:               TERMREF 17 [Predef]
    48:                 SHAREDtype 25
    50:             STRINGconst 18 [Hello]
    52:         INLINE
    53:       INLINED(13)
    55:         IDENTtpt 2 [Foo]
    57:           TYPEREFsymbol 4
    59:             THIS
    60:               TYPEREFpkg 1 [<empty>]
    62:         TRY(4)
    64:           SHAREDterm 38
    66:           SHAREDterm 42
    68:     ANNOTATION(13)
    70:       TYPEREF 19 [SourceFile]
    72:         TERMREFpkg 23 [scala[Qualified . annotation][Qualified . internal]]
    74:       APPLY(7)
    76:         SELECT 27 [<init>[Signed Signature(List(java.lang.String),scala.annotation.internal.SourceFile)]]
    78:           NEW
    79:             SHAREDtype 70
    81:         STRINGconst 28 [Foo.scala]
    83: 50 position bytes:
         0: 0 .. 78
         4: 0 .. 78
         7: 14 .. 76
        13: 6 .. 9
        14: 6 .. 6
        18: 14 .. 14
        23: 14 .. 14
        27: 14 .. 70
        30: 30 .. 33
        36: 36 .. 70
        38: 40 .. 45
        40: 42 .. 43
        42: 54 .. 70
        44: 54 .. 61
        50: 62 .. 69
        55: 73 .. 76
        62: 73 .. 76
--------------------------------------------------------------------------------