Tk Source Code

In both core-8-5-branch and trunk:


==== textDisp-32.2 elide and tags FAILED
==== Contents of test case:

    pack [text .tt -height 30 -width 100 -bd 0  -highlightthickness 0 -padx 0]
    .tt insert end  {test text using tags 1 and 3 }  {testtag1 testtag3}  {[this bit here uses tags 2 and 3]}  {testtag2
 testtag3}
    update
    # indent left margin of tag 1 by 20 pixels
    # text should be indented
    .tt tag configure testtag1 -lmargin1 20 ; update
    #1
    set res {}
    lappend res [list [.tt index "1.0 + 0 displaychars"]  [lindex [.tt bbox 1.0] 0]  [lindex [.tt bbox "1.0 + 0 displayc
hars"] 0]]
    # hide tag 1, remaining text should not be indented, since
    # the indented tag and character is hidden.
    .tt tag configure testtag1 -elide 1 ; update
    #2
    lappend res [list [.tt index "1.0 + 0 displaychars"]  [lindex [.tt bbox 1.0] 0]  [lindex [.tt bbox "1.0 + 0 displayc
hars"] 0]]
    # reset
    .tt tag configure testtag1 -lmargin1 0
    .tt tag configure testtag1 -elide 0
    # indent left margin of tag 2 by 20 pixels
    # text should not be indented, since tag1 has lmargin1 of 0.
    .tt tag configure testtag2 -lmargin1 20 ; update
    #3
    lappend res [list [.tt index "1.0 + 0 displaychars"]  [lindex [.tt bbox 1.0] 0]  [lindex [.tt bbox "1.0 + 0 displayc
hars"] 0]]
    # hide tag 1, remaining text should now be indented, but
    # the bbox of 1.0 should have zero width and zero indent,
    # since it is elided at that position.
    .tt tag configure testtag1 -elide 1 ; update
    #4
    lappend res [list [.tt index "1.0 + 0 displaychars"]  [lindex [.tt bbox 1.0] 0]  [lindex [.tt bbox "1.0 + 0 displayc
hars"] 0]]
    # reset
    .tt tag configure testtag2 -lmargin1 {}
    .tt tag configure testtag1 -elide 0
    # indent left margin of tag 3 by 20 pixels
    # text should be indented, since this tag takes
    # precedence over testtag1, and is applied to the
    # start of the text.
    .tt tag configure testtag3 -lmargin1 20 ; update
    #5
    lappend res [list [.tt index "1.0 + 0 displaychars"]  [lindex [.tt bbox 1.0] 0]  [lindex [.tt bbox "1.0 + 0 displayc
hars"] 0]]
    # hide tag 1, remaining text should still be indented,
    # since it still has testtag3 on it.  Again the
    # bbox of 1.0 should have 0.
    .tt tag configure testtag1 -elide 1 ; update
    #6
    lappend res [list [.tt index "1.0 + 0 displaychars"]  [lindex [.tt bbox 1.0] 0]  [lindex [.tt bbox "1.0 + 0 displayc
hars"] 0]]
    .tt tag configure testtag3 -lmargin1 {} -elide 0
    .tt tag configure testtag1 -elide 1 -lmargin1 20
    #7
    lappend res [list [.tt index "1.0 + 0 displaychars"]  [lindex [.tt bbox 1.0] 0]  [lindex [.tt bbox "1.0 + 0 displayc
hars"] 0]]
    destroy .tt
    set res

---- Result was:
{1.0 20 20} {1.0 0 0} {1.0 0 0} {1.0 0 0} {1.0 20 20} {1.0 0 0} {1.0 20 20}
---- Result should have been (exact matching):
{1.0 20 20} {1.29 0 0} {1.0 0 0} {1.29 0 20} {1.0 20 20} {1.29 0 20} {1.0 20 20}
==== textDisp-32.2 FAILED

allow_comments - 1

Fix merged in core-8-5-branch and trunk.

A trimmed down test case:

pack [text .tt -height 30 -width 100 -bd 0  -highlightthickness 0 -padx 0]
.tt insert end  {test text using tags 1 and 3 }  {testtag1 testtag3}
.tt insert end  {[this bit here uses tags 2 and 3]}  {testtag2 testtag3}
update
set res {}
lappend res [.tt index "1.0 + 0 displaychars"]
.tt tag configure testtag1 -elide 1 ; update
lappend res [.tt index "1.0 + 0 displaychars"]
lappend res [.tt index "1.0 + 0 display chars"]

#---- Wrong result is:
#1.0 1.0 1.29
#---- Correct result is:
#1.0 1.29 1.29

destroy .tt


Analysis:
The indices are calculated when calling the first
    lappend res [.tt index "1.0 + 0 displaychars"]
and then cached by the text widget.
When requesting
    lappend res [.tt index "1.0 + 0 displaychars"]
a second time, the cached index is returned (which is wrong).

Fix:
tag configure -elide should increase the epoch so that indices are recomputed after the elide state of tags is changed. 

I have proposed that fix in branch bug-3554273
Review welcome.