From abb58dcef1b4758f4e3af26c030e1f0630b8d145 Mon Sep 17 00:00:00 2001
From: Som Snytt <som.snytt@gmail.com>
Date: Sun, 27 Apr 2014 00:08:54 -0700
Subject: SI-6476 Improve error on escapement

Behavior of escape processing under string interpolation can
be confusing.  This commit improves the exception message so
you know at least what sort of escapes are handled.

This came up on SO in the form `s"\d".r`, where it may not
be obvious what is throwing and how to work around it.

```
scala> s"\d".r
scala.StringContext$InvalidEscapeException: invalid escape '\d' not one of [\b, \t, \n, \f, \r, \\, \", \'] at index 0 in "\d". Use \\ for literal \.

scala> s"a\"
scala.StringContext$InvalidEscapeException: invalid escape at terminal index 1 in "a\". Use \\ for literal \.
```

Referencing SI-6476 because that has become the magnet ticket
for "escape processing under string interpolation, huh?"

This doesn't address `$"` and doesn't handle the more interesting
parse error `s"a\"b"`.
---
 test/files/neg/t8266-invalid-interp.check | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

(limited to 'test')

diff --git a/test/files/neg/t8266-invalid-interp.check b/test/files/neg/t8266-invalid-interp.check
index 70dd4081b0..bb2d44a80c 100644
--- a/test/files/neg/t8266-invalid-interp.check
+++ b/test/files/neg/t8266-invalid-interp.check
@@ -1,10 +1,10 @@
 t8266-invalid-interp.scala:4: error: Trailing '\' escapes nothing.
     f"a\",
        ^
-t8266-invalid-interp.scala:5: error: invalid escape character at index 1 in "a\xc"
+t8266-invalid-interp.scala:5: error: invalid escape '\x' not one of [\b, \t, \n, \f, \r, \\, \", \'] at index 1 in "a\xc". Use \\ for literal \.
     f"a\xc",
        ^
-t8266-invalid-interp.scala:7: error: invalid escape character at index 1 in "a\vc"
+t8266-invalid-interp.scala:7: error: invalid escape '\v' not one of [\b, \t, \n, \f, \r, \\, \", \'] at index 1 in "a\vc". Use \\ for literal \.
     f"a\vc"
        ^
 three errors found
-- 
cgit v1.2.3


From b4f506749189b337bd25633d521b6b917108ee15 Mon Sep 17 00:00:00 2001
From: Som Snytt <som.snytt@gmail.com>
Date: Fri, 18 Jul 2014 22:34:01 -0700
Subject: SI-6476 Documentation

And adjust the test.
---
 src/compiler/scala/tools/nsc/ast/parser/Parsers.scala |  2 ++
 test/files/run/t6631.scala                            | 18 ------------------
 test/junit/scala/StringContextTest.scala              | 14 ++++++++++++++
 3 files changed, 16 insertions(+), 18 deletions(-)
 delete mode 100644 test/files/run/t6631.scala

(limited to 'test')

diff --git a/src/compiler/scala/tools/nsc/ast/parser/Parsers.scala b/src/compiler/scala/tools/nsc/ast/parser/Parsers.scala
index 883fd31dbc..90bc53721d 100644
--- a/src/compiler/scala/tools/nsc/ast/parser/Parsers.scala
+++ b/src/compiler/scala/tools/nsc/ast/parser/Parsers.scala
@@ -1254,6 +1254,8 @@ self =>
         }
         if (in.token == STRINGLIT) partsBuf += literal()
 
+      // Documenting that it is intentional that the ident is not rooted for purposes of virtualization
+      //val t1 = atPos(o2p(start)) { Select(Select (Ident(nme.ROOTPKG), nme.scala_), nme.StringContext) }
         val t1 = atPos(o2p(start)) { Ident(nme.StringContext) }
         val t2 = atPos(start) { Apply(t1, partsBuf.toList) }
         t2 setPos t2.pos.makeTransparent
diff --git a/test/files/run/t6631.scala b/test/files/run/t6631.scala
deleted file mode 100644
index e472b83d50..0000000000
--- a/test/files/run/t6631.scala
+++ /dev/null
@@ -1,18 +0,0 @@
-import reflect.ClassTag
-
-object Test extends App {
-  def intercept[T <: Throwable : ClassTag](act: => Any) = try {
-    act
-  } catch {
-    case x: Throwable =>
-      val cls = implicitly[ClassTag[T]].runtimeClass
-      assert(cls.isInstance(x), (x.getClass, x, cls).toString)
-  }
-  assert(s"""\f\r\n\t""" == "\f\r\n\t")
-
-  import StringContext.InvalidEscapeException
-  intercept[InvalidEscapeException](s"""\""")
-  intercept[InvalidEscapeException](s"""\x""")
-  intercept[InvalidEscapeException](s"\")
-
-}
diff --git a/test/junit/scala/StringContextTest.scala b/test/junit/scala/StringContextTest.scala
index 5abfe90cd1..bb0e8c4252 100644
--- a/test/junit/scala/StringContextTest.scala
+++ b/test/junit/scala/StringContextTest.scala
@@ -48,4 +48,18 @@ class StringContextTest {
     val res = processEscapes(s)
     assertEquals("Scala", res)
   }
+
+  @Test def t6631_baseline() = assertEquals("\f\r\n\t", s"""\f\r\n\t""")
+
+  @Test def t6631_badEscape() = assertThrows[InvalidEscapeException] {
+    s"""\x"""
+  }
+
+  // verifying that the standard interpolators can be supplanted
+  @Test def antiHijack_?() = {
+    object AllYourStringsAreBelongToMe { case class StringContext(args: Any*) { def s(args: Any) = "!!!!" } }
+    import AllYourStringsAreBelongToMe._
+    //assertEquals("????", s"????")
+    assertEquals("!!!!", s"????") // OK to hijack core interpolator ids
+  }
 }
-- 
cgit v1.2.3