From c663c9ab3ccfe87571296d840273c7fb5e43f1a3 Mon Sep 17 00:00:00 2001
From: Guillaume Munch <gm@lyx.org>
Date: Wed, 28 Sep 2016 16:05:10 +0200
Subject: [PATCH] Fix horizontal lines in math arrays

They must end at the end of the last column, not at the start of the last+1
column.
---
 src/mathed/InsetMathGrid.cpp | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/src/mathed/InsetMathGrid.cpp b/src/mathed/InsetMathGrid.cpp
index 3d60683a9b..018c96f8e2 100644
--- a/src/mathed/InsetMathGrid.cpp
+++ b/src/mathed/InsetMathGrid.cpp
@@ -622,11 +622,13 @@ void InsetMathGrid::drawWithMargin(PainterInfo & pi, int x, int y,
 						- rowinfo_[r].ascent_
 						- i * hlinesep()
 						- hlinesep()/2 - rowsep()/2;
-					pi.pain.line(
-						x + lmargin + colinfo_[c].offset_,
-						yy,
-						x + lmargin + colinfo_[c+1].offset_,
-						yy, Color_foreground);
+					int const xx1 = x + lmargin + colinfo_[c].offset_;
+					int const xx2 = (c + 1 == ncols()) ?
+						// last column
+						xx1 + colinfo_[c].width_ :
+						// first columns
+						x + lmargin + colinfo_[c+1].offset_;
+					pi.pain.line(xx1, yy, xx2, yy, Color_foreground);
 				}
 			}
 			if (c > 0 && c < ncols()) {