.

Author: lihaoyi

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

@@ -1363,6 +1363,7 @@ object Parsers {
 
       // Find the last line (should be just whitespace before closing delimiter)
       val lastNewlineIdx = str.lastIndexOf('\n')
+
       if (lastNewlineIdx < 0) {
         syntaxError(
           em"dedented string literal must start with newline after opening quotes",
@@ -1392,11 +1393,12 @@ object Parsers {
       }
 
       // Split into lines
-      val lines = str.linesIterator.toSeq
+      val linesAndWithSeps = (str.linesIterator.zip(str.linesWithSeparators)).toSeq
 
-      // Process all lines except the last (which is just the closing indentation)
+      // Process all lines except the first (which is empty before the first newline)
+      // and the last (which is just the closing indentation)
       var lineOffset = offset
-      val dedented = lines.dropRight(1).map { line =>
+      val dedented = linesAndWithSeps.drop(1).dropRight(1).map { case (line, lineWithSep) =>
         val result =
           if (line.startsWith(closingIndent)) line.substring(closingIndent.length)
           else if (line.trim.isEmpty) "" // Empty or whitespace-only lines
@@ -1418,14 +1420,11 @@ object Parsers {
             }
             line
           }
-        lineOffset += line.length + 1  // +1 for the newline
+        lineOffset += lineWithSep.length // Make sure to include any \n, \r, \r\n, or \n\r
         result
       }
 
-      // Drop the first line if it's empty (the newline after opening delimiter)
-      val result = if (dedented.headOption.contains("")) dedented.drop(1) else dedented
-
-      result.mkString("\n")
+      dedented.mkString("\n")
     }
 
     /** Literal           ::=  SimpleLiteral

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

@@ -1319,10 +1319,6 @@ object Scanners {
         return 0
       }
 
-      // Skip the initial newline (CR LF or just LF)
-      if (ch == CR) nextRawChar()
-      if (ch == LF) nextRawChar()
-
       // Collect all content using the string part parser
       getDedentedStringPartWithDelimiter(quoteCount, isInterpolated)
 
@@ -1349,11 +1345,11 @@ object Scanners {
           foundQuotes += 1
           nextRawChar()
         }
-        // The while-loop above steps forward to the first non-`'` character,
-        // so we need to backtrack 1 char to avoid consuming it
-        charOffset -= 1
 
         if (foundQuotes == quoteCount && ch != '\'') {
+          // The while-loop above steps forward to the first non-`'` character,
+          // so we need to backtrack 1 char to avoid consuming it
+          charOffset -= 1
           // Found closing delimiter - exact match and not followed by another quote
           setStrVal()
           nextChar()  // Switch from raw mode to normal mode

tests/neg/dedented-string-literals.check

@@ -14,12 +14,12 @@
 19 |  val nonWhitespaceBeforeClosing = '''
    |                                   ^
    |last line of dedented string literal must contain only whitespace before closing delimiter
+-- [E040] Syntax Error: tests/neg/dedented-string-literals.scala:41:17
+41 |  val unclosed = '''
+   |                 ^
+   |unclosed dedented string literal
 -- Error: tests/neg/dedented-string-literals.scala:35:4
 35 |    onlyAtCompileTime // error
    |    ^^^^^^^^^^^^^^^^^
    |This method should only be used at compile time
    |Do not call at runtime
--- [E040] Syntax Error: tests/neg/dedented-string-literals.scala:41:17
-41 |  val unclosed = '''
-   |                 ^
-   |unclosed dedented string literal

tests/neg/dedented-string-literals.scala

@@ -38,5 +38,5 @@ object CompileTimeOnlyTest {
 
 // Error: Unclosed literal - must be last since it breaks parsing
 object UnclosedTest {
-  val unclosed = ''' // error: unclosed dedented string literal
-some content
+  val unclosed = '''
+  some content // error: unclosed dedented string literal

tests/run/dedented-string-literals.check

@@ -55,7 +55,6 @@ Empty lines anywhere:
 content
 
 more content
-
 ]
 
 With quotes:
@@ -94,20 +93,20 @@ Interpolated pattern (two lines):
 Two line interpolated result: matched two line greeting
 
 In function:
-function content
-more content
+  function content
+  more content
 
 In class:
-class member
-content
+  class member
+  content
 
 In list:
-Item: [first]
-Item: [second]
-Item: [third]
+Item: [  first]
+Item: [  second]
+Item: [  third]
 
 Nested in expressions:
-prefixmiddlesuffix
+prefix  middlesuffix
 
 Type ascription:
 Value: [  first line

tests/run/dedented-string-literals.scala

@@ -112,8 +112,8 @@ object Test {
 
     // Test tabs for indentation
     val withTabs = '''
-	tab indented
-	content here
+		tab indented
+		content here
 	'''
     println("With tabs:")
     println(withTabs)
@@ -289,8 +289,7 @@ object Test {
     println()
 
     // Test as type parameter to valueOf
-    import scala.compiletime.valueOf
-    val valueOfResult = valueOf['''
+    val valueOfResult = scala.compiletime.constValue['''
       alpha
         beta
       gamma