From ef0d2913a628e3ce06bc81942dc236170aa744c1 Mon Sep 17 00:00:00 2001
From: Sebastian Harko <sebastian.harko@lightbend.com>
Date: Mon, 24 Oct 2016 22:52:14 -0700
Subject: add error message related to missing yield/do in for-comprehensions

---
 src/dotty/tools/dotc/parsing/Parsers.scala         |  2 +-
 .../tools/dotc/reporting/diagnostic/messages.scala | 35 ++++++++++++++++++++++
 2 files changed, 36 insertions(+), 1 deletion(-)

(limited to 'src')

diff --git a/src/dotty/tools/dotc/parsing/Parsers.scala b/src/dotty/tools/dotc/parsing/Parsers.scala
index 17e894144..5d738d5d0 100644
--- a/src/dotty/tools/dotc/parsing/Parsers.scala
+++ b/src/dotty/tools/dotc/parsing/Parsers.scala
@@ -1326,7 +1326,7 @@ object Parsers {
       if (in.token == YIELD) { in.nextToken(); ForYield(enums, expr()) }
       else if (in.token == DO) { in.nextToken(); ForDo(enums, expr()) }
       else {
-        if (!wrappedEnums) syntaxErrorOrIncomplete("`yield' or `do' expected")
+        if (!wrappedEnums) syntaxErrorOrIncomplete(YieldOrDoExpectedInForComprehension())
         ForDo(enums, expr())
       }
     }
diff --git a/src/dotty/tools/dotc/reporting/diagnostic/messages.scala b/src/dotty/tools/dotc/reporting/diagnostic/messages.scala
index c4e84aaee..264479467 100644
--- a/src/dotty/tools/dotc/reporting/diagnostic/messages.scala
+++ b/src/dotty/tools/dotc/reporting/diagnostic/messages.scala
@@ -512,4 +512,39 @@ object messages {
         |}""".stripMargin
   }
 
+  case class YieldOrDoExpectedInForComprehension()(implicit ctx: Context) extends Message(19) {
+    val kind = "Syntax"
+    val msg = hl"${"yield"} or ${"do"} expected"
+    
+    val code1 = "val numbers = for i <- 1 to 3 yield i"
+    val code2 = "val numbers = for (i <- 1 to 3) yield i"
+    val code3 = "for (i <- 1 to 3) println(i)"
+    val code4 = "for i <- 1 to 3 do println(i) // notice the 'do' keyword"
+    
+    val explanation =
+      hl"""When the enumerators in a for comprehension are not placed in parentheses or braces, a ${"do"} or ${"yield"} statement
+           |is required after the enumerators section of the comprehension.
+           |
+           |You can save some keystrokes by omitting the parentheses and writing
+           |
+           |$code1
+           |
+           |  instead of
+           |
+           |$code2
+           |
+           |but the ${"yield"} keyword is still required.
+           |
+           |For comprehensions that simply perform a side effect without yielding anything can also be written without parentheses
+           |but a ${"do"} keyword has to be included. For example,
+           |
+           |$code3
+           |
+           |  can be written as
+           |
+           |$code4
+           |
+           |""".stripMargin
+  }
+ 
 }
-- 
cgit v1.2.3


From 6660729efd3d8d74db0614947d30b3b6c08484c0 Mon Sep 17 00:00:00 2001
From: Sebastian Harko <sebastian.harko@lightbend.com>
Date: Tue, 25 Oct 2016 07:51:21 -0700
Subject: break lines

---
 .../tools/dotc/reporting/diagnostic/messages.scala | 25 ++++++++++------------
 1 file changed, 11 insertions(+), 14 deletions(-)

(limited to 'src')

diff --git a/src/dotty/tools/dotc/reporting/diagnostic/messages.scala b/src/dotty/tools/dotc/reporting/diagnostic/messages.scala
index 264479467..303ab0437 100644
--- a/src/dotty/tools/dotc/reporting/diagnostic/messages.scala
+++ b/src/dotty/tools/dotc/reporting/diagnostic/messages.scala
@@ -515,34 +515,31 @@ object messages {
   case class YieldOrDoExpectedInForComprehension()(implicit ctx: Context) extends Message(19) {
     val kind = "Syntax"
     val msg = hl"${"yield"} or ${"do"} expected"
-    
-    val code1 = "val numbers = for i <- 1 to 3 yield i"
-    val code2 = "val numbers = for (i <- 1 to 3) yield i"
-    val code3 = "for (i <- 1 to 3) println(i)"
-    val code4 = "for i <- 1 to 3 do println(i) // notice the 'do' keyword"
-    
+
     val explanation =
-      hl"""When the enumerators in a for comprehension are not placed in parentheses or braces, a ${"do"} or ${"yield"} statement
-           |is required after the enumerators section of the comprehension.
+      hl"""When the enumerators in a for comprehension are not placed in parentheses or
+           |braces, a ${"do"} or ${"yield"} statement is required after the enumerators section
+           |of the comprehension.
            |
            |You can save some keystrokes by omitting the parentheses and writing
            |
-           |$code1
+           |${"val numbers = for i <- 1 to 3 yield i"}
            |
            |  instead of
            |
-           |$code2
+           |${"val numbers = for (i <- 1 to 3) yield i"}
            |
            |but the ${"yield"} keyword is still required.
            |
-           |For comprehensions that simply perform a side effect without yielding anything can also be written without parentheses
-           |but a ${"do"} keyword has to be included. For example,
+           |For comprehensions that simply perform a side effect without yielding anything
+           |can also be written without parentheses but a ${"do"} keyword has to be included.
+           |For example,
            |
-           |$code3
+           |${"for (i <- 1 to 3) println(i)"}
            |
            |  can be written as
            |
-           |$code4
+           |${"for i <- 1 to 3 do println(i) // notice the 'do' keyword"}
            |
            |""".stripMargin
   }
-- 
cgit v1.2.3