Skip to content

Commit 9749b66

Browse files
WojciechMazurWojciechMazur
committed
Classify an id as infix operator only if following can start an operand
Also, detect and report spread operators in illegal positions [Cherry-picked ffb2ab7][modified]
1 parent e2a2803 commit 9749b66

14 files changed

+77
-65
lines changed

‎compiler/src/dotty/tools/dotc/parsing/Parsers.scala

Lines changed: 20 additions & 4 deletions
Original file line numberDiff line numberDiff line change
@@ -970,6 +970,15 @@ object Parsers {
970970
isArrowIndent()
971971
else false
972972

973+
/** Can the next lookahead token start an operand as defined by
974+
* leadingOperandTokens, or is postfix ops enabled?
975+
* This is used to decide whether the current token can be an infix operator.
976+
*/
977+
def nextCanFollowOperator(leadingOperandTokens: BitSet): Boolean =
978+
leadingOperandTokens.contains(in.lookahead.token)
979+
|| in.postfixOpsEnabled
980+
|| in.lookahead.token == COLONop
981+
973982
/* --------- OPERAND/OPERATOR STACK --------------------------------------- */
974983

975984
var opStack: List[OpInfo] = Nil
@@ -1050,7 +1059,11 @@ object Parsers {
10501059
then recur(top)
10511060
else top
10521061

1053-
recur(first)
1062+
val res = recur(first)
1063+
if isIdent(nme.raw.STAR) && !followingIsVararg() then
1064+
syntaxError(em"spread operator `*` not allowed here; must come last in a parameter list")
1065+
in.nextToken()
1066+
res
10541067
end infixOps
10551068

10561069
/* -------- IDENTIFIERS AND LITERALS ------------------------------------------- */
@@ -1671,7 +1684,8 @@ object Parsers {
16711684

16721685
def infixTypeRest(t: Tree): Tree =
16731686
infixOps(t, canStartInfixTypeTokens, refinedTypeFn, Location.ElseWhere, ParseKind.Type,
1674-
isOperator = !followingIsVararg() && !isPureArrow)
1687+
isOperator = !followingIsVararg() && !isPureArrow
1688+
&& nextCanFollowOperator(canStartInfixTypeTokens))
16751689

16761690
/** RefinedType ::= WithType {[nl] Refinement} [`^` CaptureSet]
16771691
*/
@@ -2413,7 +2427,8 @@ object Parsers {
24132427

24142428
def postfixExprRest(t: Tree, location: Location): Tree =
24152429
infixOps(t, in.canStartExprTokens, prefixExpr, location, ParseKind.Expr,
2416-
isOperator = !(location.inArgs && followingIsVararg()))
2430+
isOperator = !(location.inArgs && followingIsVararg())
2431+
&& nextCanFollowOperator(canStartInfixExprTokens))
24172432

24182433
/** PrefixExpr ::= [PrefixOperator'] SimpleExpr
24192434
* PrefixOperator ::= ‘-’ | ‘+’ | ‘~’ | ‘!’ (if not backquoted)
@@ -2920,7 +2935,8 @@ object Parsers {
29202935
def infixPattern(): Tree =
29212936
infixOps(
29222937
simplePattern(), in.canStartExprTokens, simplePatternFn, Location.InPattern, ParseKind.Pattern,
2923-
isOperator = in.name != nme.raw.BAR && !followingIsVararg())
2938+
isOperator = in.name != nme.raw.BAR && !followingIsVararg()
2939+
&& nextCanFollowOperator(canStartPatternTokens))
29242940

29252941
/** SimplePattern ::= PatVar
29262942
* | Literal

‎compiler/src/dotty/tools/dotc/parsing/Tokens.scala

Lines changed: 8 additions & 3 deletions
Original file line numberDiff line numberDiff line change
@@ -221,10 +221,13 @@ object Tokens extends TokensCommon {
221221

222222
final val openParensTokens = BitSet(LBRACE, LPAREN, LBRACKET)
223223

224-
final val canStartExprTokens3: TokenSet =
225-
atomicExprTokens
224+
final val canStartInfixExprTokens =
225+
atomicExprTokens
226226
| openParensTokens
227-
| BitSet(INDENT, QUOTE, IF, WHILE, FOR, NEW, TRY, THROW)
227+
| BitSet(QUOTE, NEW)
228+
229+
final val canStartExprTokens3: TokenSet =
230+
canStartInfixExprTokens | BitSet(INDENT, IF, WHILE, FOR, TRY, THROW)
228231

229232
final val canStartExprTokens2: TokenSet = canStartExprTokens3 | BitSet(DO)
230233

@@ -233,6 +236,8 @@ object Tokens extends TokensCommon {
233236

234237
final val canStartTypeTokens: TokenSet = canStartInfixTypeTokens | BitSet(LBRACE)
235238

239+
final val canStartPatternTokens = atomicExprTokens | openParensTokens | BitSet(USCORE, QUOTE)
240+
236241
final val templateIntroTokens: TokenSet = BitSet(CLASS, TRAIT, OBJECT, ENUM, CASECLASS, CASEOBJECT)
237242

238243
final val dclIntroTokens: TokenSet = BitSet(DEF, VAL, VAR, TYPE, GIVEN)

‎tests/neg/cc-only-defs.scala

Lines changed: 2 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -7,5 +7,5 @@ trait Test {
77

88
val b: ImpureFunction1[Int, Int] // now OK
99

10-
val a: {z} String // error
11-
} // error
10+
val a: {z} String // error // error
11+
}

‎tests/neg/i14564.check

Lines changed: 4 additions & 17 deletions
Original file line numberDiff line numberDiff line change
@@ -1,17 +1,4 @@
1-
-- [E018] Syntax Error: tests/neg/i14564.scala:5:28 --------------------------------------------------------------------
2-
5 |def test = sum"${ List(42)* }" // error // error
3-
| ^
4-
| expression expected but '}' found
5-
|
6-
| longer explanation available when compiling with `-explain`
7-
-- [E008] Not Found Error: tests/neg/i14564.scala:5:26 -----------------------------------------------------------------
8-
5 |def test = sum"${ List(42)* }" // error // error
9-
| ^^^^^^^^^
10-
| value * is not a member of List[Int], but could be made available as an extension method.
11-
|
12-
| One of the following imports might make progress towards fixing the problem:
13-
|
14-
| import scala.math.Fractional.Implicits.infixFractionalOps
15-
| import scala.math.Integral.Implicits.infixIntegralOps
16-
| import scala.math.Numeric.Implicits.infixNumericOps
17-
|
1+
-- Error: tests/neg/i14564.scala:5:26 ----------------------------------------------------------------------------------
2+
5 |def test = sum"${ List(42)* }" // error
3+
| ^
4+
| spread operator `*` not allowed here; must come last in a parameter list

‎tests/neg/i14564.scala

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -2,5 +2,5 @@ import language.postfixOps as _
22

33
extension (sc: StringContext) def sum(xs: Int*): String = xs.sum.toString
44

5-
def test = sum"${ List(42)* }" // error // error
5+
def test = sum"${ List(42)* }" // error
66

‎tests/neg/i4453.scala

Lines changed: 2 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -1,2 +1,2 @@
1-
class x0 { var x0 == _ * // error: _* can be used only for last argument // error: == cannot be used as an extractor in a pattern because it lacks an unapply or unapplySeq method
2-
// error '=' expected, but eof found
1+
class x0 { var x0 == _ * // error spread operator `*` not allowed here // error '=' expected
2+
// error: == cannot be used as an extractor in a pattern because it lacks an unapply or unapplySeq method

‎tests/neg/i5498-postfixOps.check

Lines changed: 19 additions & 7 deletions
Original file line numberDiff line numberDiff line change
@@ -4,13 +4,25 @@
44
| expression expected but end of statement found
55
|
66
| longer explanation available when compiling with `-explain`
7-
-- [E018] Syntax Error: tests/neg/i5498-postfixOps.scala:6:37 ----------------------------------------------------------
8-
6 | Seq(1, 2).filter(List(1,2) contains) // error: usage of postfix operator // error
9-
| ^
10-
| expression expected but ')' found
11-
|
12-
| longer explanation available when compiling with `-explain`
7+
-- [E040] Syntax Error: tests/neg/i5498-postfixOps.scala:6:29 ----------------------------------------------------------
8+
6 | Seq(1, 2).filter(List(1,2) contains) // error: usage of postfix operator // error // error (type error) // error (type error)
9+
| ^^^^^^^^
10+
| ')' expected, but identifier found
1311
-- [E172] Type Error: tests/neg/i5498-postfixOps.scala:6:0 -------------------------------------------------------------
14-
6 | Seq(1, 2).filter(List(1,2) contains) // error: usage of postfix operator // error
12+
6 | Seq(1, 2).filter(List(1,2) contains) // error: usage of postfix operator // error // error (type error) // error (type error)
1513
|^
1614
|No given instance of type scala.concurrent.duration.DurationConversions.Classifier[Null] was found for parameter ev of method second in trait DurationConversions
15+
-- [E007] Type Mismatch Error: tests/neg/i5498-postfixOps.scala:6:24 ---------------------------------------------------
16+
6 | Seq(1, 2).filter(List(1,2) contains) // error: usage of postfix operator // error // error (type error) // error (type error)
17+
| ^
18+
| Found: (1 : Int)
19+
| Required: Boolean
20+
|
21+
| longer explanation available when compiling with `-explain`
22+
-- [E007] Type Mismatch Error: tests/neg/i5498-postfixOps.scala:6:26 ---------------------------------------------------
23+
6 | Seq(1, 2).filter(List(1,2) contains) // error: usage of postfix operator // error // error (type error) // error (type error)
24+
| ^
25+
| Found: (2 : Int)
26+
| Required: Boolean
27+
|
28+
| longer explanation available when compiling with `-explain`

‎tests/neg/i5498-postfixOps.scala

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -3,5 +3,5 @@ import scala.concurrent.duration.*
33
def test() = {
44
1 second // error: usage of postfix operator
55

6-
Seq(1, 2).filter(List(1,2) contains) // error: usage of postfix operator // error
6+
Seq(1, 2).filter(List(1,2) contains) // error: usage of postfix operator // error // error (type error) // error (type error)
77
}

‎tests/neg/i6059.scala

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -1,3 +1,3 @@
11
def I0(I1: Int ) = I1
2-
val I1 = I0(I0 i2) => // error
2+
val I1 = I0(I0 i2) => // error // error
33
true

‎tests/neg/t11900.check

Lines changed: 3 additions & 5 deletions
Original file line numberDiff line numberDiff line change
@@ -10,9 +10,7 @@
1010
52 | println("b"), // error: weird comma
1111
| ^
1212
| end of statement expected but ',' found
13-
-- [E032] Syntax Error: tests/neg/t11900.scala:64:8 --------------------------------------------------------------------
13+
-- Error: tests/neg/t11900.scala:64:7 ----------------------------------------------------------------------------------
1414
64 | _*, // error
15-
| ^
16-
| pattern expected
17-
|
18-
| longer explanation available when compiling with `-explain`
15+
| ^
16+
| spread operator `*` not allowed here; must come last in a parameter list

‎tests/neg/t1625.check

Lines changed: 6 additions & 6 deletions
Original file line numberDiff line numberDiff line change
@@ -1,8 +1,8 @@
1-
-- [E040] Syntax Error: tests/neg/t1625.scala:2:20 ---------------------------------------------------------------------
1+
-- Error: tests/neg/t1625.scala:2:19 -----------------------------------------------------------------------------------
22
2 | def foo(x: String*, y: String*, c: String*): Int // error: an identifier expected, but ',' found // error: an identifier expected, but ',' found
3-
| ^
4-
| an identifier expected, but ',' found
5-
-- [E040] Syntax Error: tests/neg/t1625.scala:2:32 ---------------------------------------------------------------------
3+
| ^
4+
| spread operator `*` not allowed here; must come last in a parameter list
5+
-- Error: tests/neg/t1625.scala:2:31 -----------------------------------------------------------------------------------
66
2 | def foo(x: String*, y: String*, c: String*): Int // error: an identifier expected, but ',' found // error: an identifier expected, but ',' found
7-
| ^
8-
| an identifier expected, but ',' found
7+
| ^
8+
| spread operator `*` not allowed here; must come last in a parameter list

‎tests/neg/t1625b.scala

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -1,3 +1,3 @@
11
object T5 {
2-
case class Abc(x: String*, c: String*) // error: identifier expected but `,` found
2+
case class Abc(x: String*, c: String*) // error: varargs parameter must come last
33
}

‎tests/neg/t5702-neg-bad-and-wild.check

Lines changed: 6 additions & 10 deletions
Original file line numberDiff line numberDiff line change
@@ -14,24 +14,20 @@
1414
13 | case List(1, _*3:) => // error // error
1515
| ^
1616
| an identifier expected, but ')' found
17-
-- [E032] Syntax Error: tests/neg/t5702-neg-bad-and-wild.scala:15:18 ---------------------------------------------------
17+
-- Error: tests/neg/t5702-neg-bad-and-wild.scala:15:17 -----------------------------------------------------------------
1818
15 | case List(x*, 1) => // error: pattern expected
19-
| ^
20-
| pattern expected
21-
|
22-
| longer explanation available when compiling with `-explain`
19+
| ^
20+
| spread operator `*` not allowed here; must come last in a parameter list
2321
-- [E031] Syntax Error: tests/neg/t5702-neg-bad-and-wild.scala:17:18 ---------------------------------------------------
2422
17 | case (1, x: _*) => // error: bad use of _* (sequence pattern not allowed)
2523
| ^
2624
| * can be used only for last argument
2725
|
2826
| longer explanation available when compiling with `-explain`
29-
-- [E032] Syntax Error: tests/neg/t5702-neg-bad-and-wild.scala:23:17 ---------------------------------------------------
27+
-- Error: tests/neg/t5702-neg-bad-and-wild.scala:23:16 -----------------------------------------------------------------
3028
23 | val K(ns @ _*, xx) = k // error: pattern expected
31-
| ^
32-
| pattern expected
33-
|
34-
| longer explanation available when compiling with `-explain`
29+
| ^
30+
| spread operator `*` not allowed here; must come last in a parameter list
3531
-- [E161] Naming Error: tests/neg/t5702-neg-bad-and-wild.scala:24:10 ---------------------------------------------------
3632
24 | val K(x) = k // error: x is already defined as value x
3733
| ^^^^^^^^^^^^

‎tests/neg/t5702-neg-bad-brace.check

Lines changed: 3 additions & 5 deletions
Original file line numberDiff line numberDiff line change
@@ -1,9 +1,7 @@
1-
-- [E032] Syntax Error: tests/neg/t5702-neg-bad-brace.scala:8:21 -------------------------------------------------------
1+
-- Error: tests/neg/t5702-neg-bad-brace.scala:8:20 ---------------------------------------------------------------------
22
8 | case List(1, _*} => // error: pattern expected
3-
| ^
4-
| pattern expected
5-
|
6-
| longer explanation available when compiling with `-explain`
3+
| ^
4+
| spread operator `*` not allowed here; must come last in a parameter list
75
-- [E040] Syntax Error: tests/neg/t5702-neg-bad-brace.scala:11:0 -------------------------------------------------------
86
11 |} // error: eof expected, but '}' found
97
|^

0 commit comments

Comments
 (0)