diff --git a/test/lib/completion.exp b/test/lib/completion.exp
index 299f2691..c7efff66 100644
--- a/test/lib/completion.exp
+++ b/test/lib/completion.exp
@@ -8,7 +8,7 @@ proc completion_exit {} {
 
 
 proc completion_start {} {
-    global bash_versinfo_0 TESTDIR TOOL_EXECUTABLE spawn_id
+    global bash_versinfo_0 COMP_WORDBREAKS TESTDIR TOOL_EXECUTABLE spawn_id
     set test "completion_start"
     set TESTDIR [pwd]
 
@@ -23,6 +23,7 @@ proc completion_start {} {
     assert_bash_exec {source $BASH_COMPLETION}
     # Fill global var `bash_versinfo_0' with bash major version number
     assert_bash_exec {printf "%s" "${BASH_VERSINFO[0]}"} "" /@ bash_versinfo_0
+    assert_bash_exec {printf "%s" "$COMP_WORDBREAKS"} "" /@ COMP_WORDBREAKS
 }; # completion_start()
 
 
diff --git a/test/lib/completions/ssh.exp b/test/lib/completions/ssh.exp
index 6afd3397..c3341294 100644
--- a/test/lib/completions/ssh.exp
+++ b/test/lib/completions/ssh.exp
@@ -75,7 +75,7 @@ sync_after_int
 
 
 set test "First argument should complete partial hostname"
-assert_complete_partial [get_hosts] ssh
+assert_complete_partial [get_hosts] ssh "" $test /@ 20 [list "ltrim_colon_completions"]
 
 
 sync_after_int
diff --git a/test/lib/library.exp b/test/lib/library.exp
index 730e98ba..7a13b9fa 100644
--- a/test/lib/library.exp
+++ b/test/lib/library.exp
@@ -109,21 +109,26 @@ proc assert_bash_list {expected cmd {test ""} {prompt /@} {size 20}} {
 #     doesn't end with whitespace.  Specifying `cword' is only necessary if
 #     this autodetection fails, e.g.  when the last whitespace is escaped or
 #     quoted, e.g. "finger foo\ " or "finger 'foo "
+# @param list $filters  (optional) List of filters to apply to this function to tweak
+#     the expected completions and argument-to-complete.  Possible values:
+#     - "ltrim_colon_completions"
 # @result boolean  True if successful, False if not
-proc assert_complete {expected cmd {test ""} {prompt /@} {size 20} {cword ""}} {
+proc assert_complete {expected cmd {test ""} {prompt /@} {size 20} {cword ""} {filters ""}} {
     if {$test == ""} {set test "$cmd should show completions"}
     send "$cmd\t"
     if {[llength $expected] == 1} {
         expect -ex "$cmd"
-        set cmds [split $cmd]
-        set cur "";  # Default to empty word to complete on
-        if {[llength $cmds] > 1} {
-                # Assume last word of `$cmd' is word to complete on.
-            set cur [lindex $cmds [expr [llength $cmds] - 1]]
-        }; # if
-            # Remove second word from beginning of single item $expected
-        if {[string first $cur $expected] == 0} {
-            set expected [string range $expected [string length $cur] end]
+        if {[lsearch -exact $filters "ltrim_colon_completions"] == -1} {
+            set cmds [split $cmd]
+            set cur "";  # Default to empty word to complete on
+            if {[llength $cmds] > 1} {
+                    # Assume last word of `$cmd' is word to complete on.
+                set cur [lindex $cmds [expr [llength $cmds] - 1]]
+            }; # if
+                # Remove second word from beginning of single item $expected
+            if {[string first $cur $expected] == 0} {
+                set expected [string range $expected [string length $cur] end]
+            }; # if
         }; # if
     } else {
         expect -ex "$cmd\r\n"
@@ -131,6 +136,12 @@ proc assert_complete {expected cmd {test ""} {prompt /@} {size 20} {cword ""}} {
         set expected [lsort -unique $expected]
     }; # if
 
+    if {[lsearch -exact $filters "ltrim_colon_completions"] != -1} {
+            # If partial contains colon (:), remove partial from begin of items
+            # See also: bash_completion.__ltrim_colon_completions()
+        _ltrim_colon_completions cword expected
+    }; # if
+
     if {[match_items $expected $test]} {
         if {[llength $expected] == 1} {
             pass "$test"
@@ -138,7 +149,12 @@ proc assert_complete {expected cmd {test ""} {prompt /@} {size 20} {cword ""}} {
             # Remove optional (partial) last argument-to-complete from `cmd',
             # E.g. "finger test@" becomes "finger"
 
-            set cmd2 [_remove_cword_from_cmd $cmd $cword]
+            if {[lsearch -exact $filters "ltrim_colon_completions"] != -1} {
+                set cmd2 $cmd
+            } else {
+                set cmd2 [_remove_cword_from_cmd $cmd $cword]
+            }; # if
+
             # Determine common prefix of completions
             set common [::textutil::string::longestCommonPrefixList $expected]
             #if {[string length $common] > 0} {set common " $common"}
@@ -249,8 +265,11 @@ proc assert_complete_dir {expected cmd dir {test ""} {size 20} {cword ""}} {
 # @param string $test  (optional) Test titel.  Default is "$cmd<TAB> should show completions"
 # @param string $prompt  (optional) Bash prompt.  Default is "/@"
 # @param integer $size  (optional) Chunk size.  Default is 20.
+# @param list $filters  (optional) List of filters to apply to this function to tweak
+#     the expected completions and argument-to-complete.
+#     @see assert_complete()
 # @result boolean  True if successful, False if not
-proc assert_complete_partial {expected cmd {partial ""} {test ""} {prompt /@} {size 20}} {
+proc assert_complete_partial {expected cmd {partial ""} {test ""} {prompt /@} {size 20} {filters ""}} {
     if {$test == ""} {set test "$cmd should complete partial argument"}
     if {[llength $expected] == 0} {
         unresolved "$test"
@@ -265,11 +284,36 @@ proc assert_complete_partial {expected cmd {partial ""} {test ""} {prompt /@} {s
                 lappend pick $item
             }; # if
         }; # foreach
-        assert_complete $pick "$cmd $partial" $test $prompt $size $partial
+        assert_complete $pick "$cmd $partial" $test $prompt $size $partial $filters
     }; # if
 }; # assert_complete_partial()
 
 
+# See also: bash_completion._ltrim_colon_completions
+proc _ltrim_colon_completions {cword items} {
+    upvar 1 $cword cword_out
+    upvar 1 $items items_out
+    # If word-to-complete contains a colon,
+    # and bash-version < 4,
+    # or bash-version >= 4 and COMP_WORDBREAKS contains a colon
+    if {
+        [string first : $cword_out] > -1 && (
+            $::bash_versinfo_0 < 4 ||
+            ($::bash_versinfo_0 >= 4 && [string first ":" $::COMP_WORDBREAKS] > -1)
+        )
+    } {
+        for {set i 0} {$i < [llength $items_out]} {incr i} {
+            set item [lindex $items_out $i]
+            if {[string first $cword_out $item] == 0} {
+                # Strip colon-prefix
+                lset items_out $i [string range $item [string length $cword_out] end]
+            }; # if
+        }; # for
+        #set cword_out ""
+    }; # if
+}; # _ltrim_colon_completions()
+
+
 # Make sure the bash environment hasn't changed between now and the last call
 # to `save_env()'.
 # @param string $sed  Sed commands to preprocess diff output.
@@ -422,6 +466,7 @@ proc get_signals {} {
 proc match_items {items test {size 20}} {
     # NOTE: `exec sort' is used instead of `lsort' to achieve exactly the
     #       same sort order as in bash -- FVu, Wed Nov 25 22:25:28 CET 2009
+    #set items [list [exec sort << [join $items "\n"]]]
     set items [exec sort << [join $items "\n"]]
     set result false
     for {set i 0} {$i < [llength $items]} {set i [expr {$i + $size}]} {
diff --git a/test/lib/unit.exp b/test/lib/unit.exp
index 14e64cca..36096c07 100644
--- a/test/lib/unit.exp
+++ b/test/lib/unit.exp
@@ -8,7 +8,7 @@ proc unit_exit {} {
 
 
 proc unit_start {} {
-    global bash_versinfo_0 TESTDIR TOOL_EXECUTABLE spawn_id
+    global bash_versinfo_0 COMP_WORDBREAKS TESTDIR TOOL_EXECUTABLE spawn_id
     set test "unit_start"
     set TESTDIR [pwd]
 
@@ -29,6 +29,7 @@ proc unit_start {} {
     assert_bash_exec {source $BASH_COMPLETION}
     # Fill global var `bash_versinfo_0' with bash major version number
     assert_bash_exec {printf "%s" "${BASH_VERSINFO[0]}"} "" /@ bash_versinfo_0
+    assert_bash_exec {printf "%s" "$COMP_WORDBREAKS"} {} /@ COMP_WORDBREAKS
 }; # unit_start()