gdi32: Correction of WidenPath behaviour when pen width is 1.

dlls/gdi32/path.c

@@ -1795,6 +1795,11 @@ static BOOL PATH_WidenPath(DC *dc)
     penWidth = elp->elpWidth;
     HeapFree( GetProcessHeap(), 0, elp );
 
+    /* pen width must be strictly higher than 1 */
+    if(penWidth == 1) {
+        return TRUE;
+    }
+
     /* FIXME : If extPen, use the shape on corners */
     penWidthIn = penWidth / 2;
     penWidthOut = penWidth / 2;

dlls/gdi32/tests/path.c

@@ -19,6 +19,7 @@
  */
 
 #include <stdarg.h>
+#include <stdio.h>
 #include "windef.h"
 #include "winbase.h"
 #include "wingdi.h"
@@ -31,7 +32,7 @@
 static void test_widenpath(void)
 {
     HDC hdc = GetDC(0);
-    HPEN greenPen;
+    HPEN greenPen, narrowPen;
     HPEN oldPen;
     POINT pnt[6];
     INT nSize;
@@ -67,6 +68,8 @@ static void test_widenpath(void)
     ok(nSize != -1, "GetPath fails after calling WidenPath.\n");
     ok(nSize > 6, "Path number of points is to low. Should be more than 6 but is %d\n", nSize);
 
+    AbortPath(hdc);
+
     todo_wine {
         /* Test WidenPath with an empty path */
         SetLastError(0xdeadbeef);
@@ -74,6 +77,17 @@ static void test_widenpath(void)
         ok(WidenPath(hdc) == FALSE, "WidenPath fails while widening an empty path. Error : %d\n", GetLastError());
     }
 
+    AbortPath(hdc);
+
+    /* Test when the pen width is equal to 1. The path should not change */
+    narrowPen = CreatePen(PS_SOLID, 1, RGB(0,0,0));
+    oldPen = SelectObject(hdc, narrowPen);
+    BeginPath(hdc);
+    Polyline(hdc, pnt, 6);
+    EndPath(hdc);
+    nSize = GetPath(hdc, NULL, NULL, 0);
+    ok(nSize == 6, "WidenPath fails detecting 1px wide pen. Path length is %d, should be 6\n", nSize);
+
     ReleaseDC(0, hdc);
     return;
 }