Index: openacs-4/packages/acs-tcl/tcl/utilities-procs.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/acs-tcl/tcl/utilities-procs.tcl,v
diff -u -N -r1.189.2.105 -r1.189.2.106
--- openacs-4/packages/acs-tcl/tcl/utilities-procs.tcl	29 Nov 2021 14:33:47 -0000	1.189.2.105
+++ openacs-4/packages/acs-tcl/tcl/utilities-procs.tcl	29 Nov 2021 16:56:03 -0000	1.189.2.106
@@ -3453,7 +3453,7 @@
             set sv [expr {$d_end + 1}]
         } elseif {[regexp {^a(\d+)$} $diff full m1]} {
             set d_end $m1
-            for {set i $sv} {$i < $m1} {incr i} {
+            for {set i $sv} {$i <= $m1} {incr i} {
                 append res "${split_by}[lindex $old_w $i]"
             }
             while {1} {
Index: openacs-4/packages/acs-tcl/tcl/test/utilities-procs.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/acs-tcl/tcl/test/Attic/utilities-procs.tcl,v
diff -u -N -r1.1.2.8 -r1.1.2.9
--- openacs-4/packages/acs-tcl/tcl/test/utilities-procs.tcl	24 Jun 2021 11:31:50 -0000	1.1.2.8
+++ openacs-4/packages/acs-tcl/tcl/test/utilities-procs.tcl	29 Nov 2021 16:56:03 -0000	1.1.2.9
@@ -241,6 +241,54 @@
     }
 }
 
+aa_register_case -cats {
+    api
+    smoke
+    production_safe
+} -procs {
+    util::word_diff
+} word_diff {
+    Test the util::word_diff proc.
+} {
+    #
+    # Equal length
+    #
+    set cases {
+        {
+            -name "add"
+            -old "hello world"
+            -new "hello2 world"
+            -result {hello<u><b><font color="red">2</font></b></u> world}
+        }
+
+        {
+            -name "delete"
+            -old "hello2 world"
+            -new "hello world"
+            -result {hello<strike><i><font color="blue">2</font></i></strike> world}
+        }
+
+        {
+            -name "add begin end"
+            -old "ello"
+            -new "hello2"
+            -result {<u><b><font color="red">h</font></b></u>ello<u><b><font color="red">2</font></b></u>}
+        }
+
+        {
+            -name "delete begin end"
+            -old "hello2"
+            -new "ello"
+            -result {<strike><i><font color="blue">h</font></i></strike>ello<strike><i><font color="blue">2</font></i></strike>}
+        }
+    }
+    foreach case $cases {
+        aa_equals "diff [dict get $case -name]" \
+            [util::word_diff -old [dict get $case -old] -new [dict get $case -new]] \
+            [dict get $case -result]
+    }
+}
+
 # Local variables:
 #    mode: tcl
 #    tcl-indent-level: 4