scala213Source3 - allow infix op after NL

Original PR in compiler - scala/scala#8419 Fixes scalameta#2739.
dos65 · Apr 26, 2022 · 31d1632 · 31d1632
1 parent 1a9ec6f
commit 31d1632
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Showing 5 changed files with 30 additions and 9 deletions.
diff --git a/scalameta/dialects/shared/src/main/scala/scala/meta/Dialect.scala b/scalameta/dialects/shared/src/main/scala/scala/meta/Dialect.scala
@@ -150,7 +150,9 @@ final class Dialect private (
     // import a.b.c.{ given, _} used for -X:source3
     val allowGivenImports: Boolean,
     // Scala 3 uses proper precedence rules for infix types, unlike Scala 2
-    val useInfixTypePrecedence: Boolean
+    val useInfixTypePrecedence: Boolean,
+    // Scala213Source3 and Scala3 allow infix operator being placed after nl
+    val allowInfixOperatorAfterNL: Boolean
 ) extends Product with Serializable {
 
   // NOTE(olafur) checklist for adding a new dialect field in a binary compatible way:
@@ -239,7 +241,8 @@ final class Dialect private (
       allowPlusMinusUnderscoreAsIdent = false,
       allowPlusMinusUnderscoreAsPlaceholder = false,
       allowGivenImports = false,
-      useInfixTypePrecedence = false
+      useInfixTypePrecedence = false,
+      allowInfixOperatorAfterNL = false
       // NOTE(olafur): declare the default value for new fields above this comment.
     )
   }
@@ -429,6 +432,10 @@ final class Dialect private (
     privateCopy(useInfixTypePrecedence = newValue)
   }
 
+  def withAllowInfixOperatorAfterNL(newValue: Boolean): Dialect = {
+    privateCopy(allowInfixOperatorAfterNL = newValue)
+  }
+
   // NOTE(olafur): add the next `withX()` method above this comment. Please try
   // to use consistent formatting, use `newValue` as the parameter name and wrap
   // the body inside curly braces.
@@ -491,8 +498,8 @@ final class Dialect private (
       allowPlusMinusUnderscoreAsIdent: Boolean = this.allowPlusMinusUnderscoreAsIdent,
       allowPlusMinusUnderscoreAsPlaceholder: Boolean = this.allowPlusMinusUnderscoreAsPlaceholder,
       allowGivenImports: Boolean = this.allowGivenImports,
-      useInfixTypePrecedence: Boolean = this.useInfixTypePrecedence
-
+      useInfixTypePrecedence: Boolean = this.useInfixTypePrecedence,
+      allowInfixOperatorAfterNL: Boolean = this.allowInfixOperatorAfterNL
       // NOTE(olafur): add the next parameter above this comment.
   ): Dialect = {
     new Dialect(
@@ -552,7 +559,8 @@ final class Dialect private (
       allowPlusMinusUnderscoreAsIdent,
       allowPlusMinusUnderscoreAsPlaceholder,
       allowGivenImports,
-      useInfixTypePrecedence
+      useInfixTypePrecedence,
+      allowInfixOperatorAfterNL
       // NOTE(olafur): add the next argument above this comment.
     )
   }

diff --git a/scalameta/dialects/shared/src/main/scala/scala/meta/dialects/package.scala b/scalameta/dialects/shared/src/main/scala/scala/meta/dialects/package.scala
@@ -65,6 +65,7 @@ package object dialects {
     .withAllowPostfixStarVarargSplices(true)
     .withAllowPlusMinusUnderscoreAsIdent(true)
     .withAllowGivenImports(true)
+    .withAllowInfixOperatorAfterNL(true)
 
   /**
    * Dialect starting with Scala 2.12.14 for `-Xsource:3` option
@@ -145,6 +146,7 @@ package object dialects {
     .withAllowDoWhile(false)
     .withAllowPlusMinusUnderscoreAsPlaceholder(true)
     .withUseInfixTypePrecedence(true)
+    .withAllowInfixOperatorAfterNL(true)
 
   @deprecated("Use Scala3 instead", "4.4.2")
   implicit val Dotty = Scala3

diff --git a/scalameta/parsers/shared/src/main/scala/scala/meta/internal/parsers/LazyTokenIterator.scala b/scalameta/parsers/shared/src/main/scala/scala/meta/internal/parsers/LazyTokenIterator.scala
@@ -360,7 +360,7 @@ private[parsers] class LazyTokenIterator private (
           case _: RegionIndent | _: RegionIndentEnum => true
           case x: RegionParen => x.canProduceLF
           case _ => false
-        }
+        } && !next.isLeadingInfixOperator
       }
 
       def getIfCanProduceLF =

diff --git a/scalameta/parsers/shared/src/main/scala/scala/meta/internal/parsers/ScannerTokens.scala b/scalameta/parsers/shared/src/main/scala/scala/meta/internal/parsers/ScannerTokens.scala
@@ -106,7 +106,7 @@ class ScannerTokens(tokens: Tokens, input: Input)(implicit dialect: Dialect) {
       @inline
       def strictNext: Token = getStrictAfterSafe(nextSafe)
 
-      def isLeadingInfixOperator: Boolean = dialect.allowSignificantIndentation && {
+      def isLeadingInfixOperator: Boolean = dialect.allowInfixOperatorAfterNL && {
         val text = token.text
         @tailrec
         def iter(idx: Int, nonEmpty: Boolean): Boolean = {

diff --git a/tests/shared/src/test/scala/scala/meta/tests/parsers/Scala213Suite.scala b/tests/shared/src/test/scala/scala/meta/tests/parsers/Scala213Suite.scala
@@ -1,6 +1,8 @@
 package scala.meta.tests
 package parsers
 
+import scala.meta.Dialect
+import scala.meta.dialects
 import scala.meta.dialects.Scala213
 
 class Scala213Suite extends ParseSuite {
@@ -78,9 +80,18 @@ class Scala213Suite extends ParseSuite {
     runAssert("try ()", """Term.Try(Lit.Unit(()), Nil, None)""")
   }
 
-  private def runAssert(code: String, expected: String): Unit = {
+  test("infix-at-line-start") {
+    runAssert(
+      """|val x = "hello"
+         |  ++ "world"
+         |""".stripMargin,
+      """Defn.Val(Nil, List(Pat.Var(Term.Name("x"))), None, Term.ApplyInfix(Lit.String("hello"), Term.Name("++"), Nil, List(Lit.String("world"))))"""
+    )(dialects.Scala213Source3)
+  }
+
+  private def runAssert(code: String, expected: String)(implicit d: Dialect): Unit = {
     assertNoDiff(
-      templStat(code).structure,
+      templStat(code)(d).structure,
       expected
     )
   }