From 6efce2dd67c8f75f081d09b7c4f703eb1724882b Mon Sep 17 00:00:00 2001
From: Humza Shahid <humzasaur@gmail.com>
Date: Sat, 27 Dec 2025 09:45:11 +0000
Subject: [PATCH] make 'dW' motion use transition function that is specific for
 deleting, and add a test to ensure that 'dW' does not delete a newline when
 it is not on a newline character

---
 fcore/cursor.sml                         |  1 +
 fcore/normal-mode/make-normal-delete.sml | 14 ++++++++++++
 fcore/normal-mode/normal-mode.sml        |  4 ++--
 test/normal-delete.sml                   | 27 +++++++++++++++++++++---
 4 files changed, 41 insertions(+), 5 deletions(-)

diff --git a/fcore/cursor.sml b/fcore/cursor.sml
index c162d3a..84fdafe 100644
--- a/fcore/cursor.sml
+++ b/fcore/cursor.sml
@@ -64,6 +64,7 @@ struct
 
   (* equivalent of vi's 'W' command *)
   val nextWORD = ViCapsWordDfa.startOfNextWORD
+  val nextWORDForDelete = ViCapsWordDfa.startOfNextWORDForDelete
 
   (* equivalent of vi's 'b' command *)
   val prevWord = ViWordDfa.startOfCurrentWord
diff --git a/fcore/normal-mode/make-normal-delete.sml b/fcore/normal-mode/make-normal-delete.sml
index 8436ab9..2cf035a 100644
--- a/fcore/normal-mode/make-normal-delete.sml
+++ b/fcore/normal-mode/make-normal-delete.sml
@@ -341,6 +341,20 @@ struct
         deleteAndFinish (app, cursorIdx, length, buffer, time)
       end
 
+  fun deleteWORD (app as {buffer, ...}: app_type, count, time) =
+    if #textLength buffer = 1 then
+      NormalFinish.clearMode app
+    else
+      let
+        val {buffer, cursorIdx, ...} = app
+
+        val buffer = LineGap.goToIdx (cursorIdx, buffer)
+        val high = Cursor.nextWORDForDelete (buffer, cursorIdx, count)
+        val length = high - cursorIdx
+      in
+        deleteAndFinish (app, cursorIdx, length, buffer, time)
+      end
+
   fun deleteByDfa (app as {buffer, ...}: app_type, count, fMove, time) =
     if #textLength buffer = 1 then
       NormalFinish.clearMode app
diff --git a/fcore/normal-mode/normal-mode.sml b/fcore/normal-mode/normal-mode.sml
index 9efd867..45095b9 100644
--- a/fcore/normal-mode/normal-mode.sml
+++ b/fcore/normal-mode/normal-mode.sml
@@ -258,7 +258,7 @@ struct
       | #"j" => NormalDelete.deleteLineDown (app, count, time)
       | #"k" => NormalDelete.deleteLineBack (app, count, time)
       | #"w" => NormalDelete.deleteWord (app, count, time)
-      | #"W" => NormalDelete.deleteByDfa (app, count, Cursor.nextWORD, time)
+      | #"W" => NormalDelete.deleteWORD (app, count, time)
       | #"b" => NormalDelete.deleteByDfa (app, count, Cursor.prevWord, time)
       | #"B" => NormalDelete.deleteByDfa (app, count, Cursor.prevWORD, time)
       | #"e" =>
@@ -347,7 +347,7 @@ struct
       | #"j" => NormalYankDelete.deleteLineDown (app, count, time)
       | #"k" => NormalYankDelete.deleteLineBack (app, count, time)
       | #"w" => NormalYankDelete.deleteWord (app, count, time)
-      | #"W" => NormalYankDelete.deleteByDfa (app, count, Cursor.nextWORD, time)
+      | #"W" => NormalYankDelete.deleteWORD (app, count, time)
       | #"b" => NormalYankDelete.deleteByDfa (app, count, Cursor.prevWord, time)
       | #"B" => NormalYankDelete.deleteByDfa (app, count, Cursor.prevWORD, time)
       | #"e" =>
diff --git a/test/normal-delete.sml b/test/normal-delete.sml
index 3cc4c4a..ab6f382 100644
--- a/test/normal-delete.sml
+++ b/test/normal-delete.sml
@@ -1197,8 +1197,29 @@ struct
         in
           Expect.isTrue (stringsAreExpected andalso cursorsAreExpected)
         end)
+    , test "does not delete newline following WORD" (fn _ =>
+        let
+          (* arrange *)
+          val originalString = "hello\nworld\nagain\n"
+          val app = TestUtils.init originalString
+          val app = AppWith.idx (app, 0)
+
+          (* act *)
+          val {buffer, cursorIdx, ...} = TestUtils.updateMany (app, "dW")
+
+          (* assert *)
+          val expectedString = "\nworld\nagain\n"
+          val expectedCursor = 0
+
+          val actualString = LineGap.toString buffer
+
+          val stringIsExpected = expectedString = actualString
+          val cursorIsExpected = expectedCursor = cursorIdx
+        in
+          Expect.isTrue (stringIsExpected andalso cursorIsExpected)
+        end)
     , test
-        "deletes newline when there is a newline after current word \
+        "does not delete newline when there is a newline after current word \
         \and there is another word following that newline"
         (fn _ =>
            let
@@ -1211,8 +1232,8 @@ struct
              val {buffer, cursorIdx, ...} = TestUtils.updateMany (app, "dW")
 
              (* assert *)
-             val expectedString = "hworld\nagain\n"
-             val expectedCursor = 1
+             val expectedString = "h\nworld\nagain\n"
+             val expectedCursor = 0
 
              val actualString = LineGap.toString buffer