Add TODOTXT_FINAL_FILTER to provide a final custom list filter.

The idea behind this is to allow a config file or addon to inject
a list output filter after all the other filtering has been
performed. The existing TODOTXT_SORT_COMMAND provides a hook
for a custom filter prior to colorization and priority/context/proj
hiding; this new TODOTXT_FINAL_FILTER provides a hook for custom
filtering after the colorization and pri/con/proj hiding.

(I found this hook was needed when I wanted to trim the output to a
maximum line length.)

Note: I've added a number of tests of the list command, including
one for this new variable, as part of this change.

Signed-off-by: Emil Sit <sit@emilsit.net>

tests/t1300-ls.sh

@@ -0,0 +1,515 @@
+#!/bin/sh
+#
+
+test_description='list functionality
+
+This test checks various list functionality including
+sorting, output filtering and line numbering.
+'
+. ./test-lib.sh
+
+TEST_TODO_=todo.cfg
+
+cat > todo.txt <<EOF
+ccc xxx this line should be third.
+aaa zzz this line should be first.
+bbb yyy this line should be second.
+EOF
+
+#
+# check the sort filter
+#
+TEST_TODO1_=todo1.cfg
+sed -e "s/^.*export TODOTXT_SORT_COMMAND=.*$/export TODOTXT_SORT_COMMAND='env LC_COLLATE=C sort -r -f -k2'/" "${TEST_TODO_}" > "${TEST_TODO1_}"
+
+test_todo_session 'checking TODOTXT_SORT_COMMAND' <<EOF
+>>> todo.sh ls
+2 aaa zzz this line should be first.
+3 bbb yyy this line should be second.
+1 ccc xxx this line should be third.
+--
+TODO: 3 of 3 tasks shown from $HOME/todo.txt
+
+>>> todo.sh -d "$TEST_TODO1_" ls
+1 ccc xxx this line should be third.
+3 bbb yyy this line should be second.
+2 aaa zzz this line should be first.
+--
+TODO: 3 of 3 tasks shown from $HOME/todo.txt
+EOF
+
+#
+# check the final filter
+#
+TEST_TODO2_=todo2.cfg
+sed -e "s%^.*export TODOTXT_FINAL_FILTER=.*$%export TODOTXT_FINAL_FILTER=\"sed 's/^\\\(..\\\{20\\\}\\\).....*$/\\\1.../'\"%" "${TEST_TODO_}" > "${TEST_TODO2_}"
+
+test_todo_session 'checking TODOTXT_FINAL_FILTER' <<EOF
+>>> todo.sh -d "$TEST_TODO2_" ls
+2 aaa zzz this line s...
+3 bbb yyy this line s...
+1 ccc xxx this line s...
+--
+TODO: 3 of 3 tasks shown from $HOME/todo.txt
+EOF
+
+#
+# check the  p command line option
+#
+cat > todo.txt <<EOF
+(A) @con01 +prj01 -- Some project 01 task, pri A
+(A) @con01 +prj02 -- Some project 02 task, pri A
+(A) @con02 +prj03 -- Some project 03 task, pri A
+(A) @con02 +prj04 -- Some project 04 task, pri A
+(B) @con01 +prj01 -- Some project 01 task, pri B
+(B) @con01 +prj02 -- Some project 02 task, pri B
+(B) @con02 +prj03 -- Some project 03 task, pri B
+(B) @con02 +prj04 -- Some project 04 task, pri B
+(C) @con01 +prj01 -- Some project 01 task, pri C
+(C) @con01 +prj02 -- Some project 02 task, pri C
+(C) @con02 +prj03 -- Some project 03 task, pri C
+(C) @con02 +prj04 -- Some project 04 task, pri C
+(D) @con01 +prj01 -- Some project 01 task, pri D
+(D) @con01 +prj02 -- Some project 02 task, pri D
+(D) @con02 +prj03 -- Some project 03 task, pri D
+(D) @con02 +prj04 -- Some project 04 task, pri D
+@con01 +prj01 -- Some project 01 task, no priority
+@con01 +prj02 -- Some project 02 task, no priority
+@con02 +prj03 -- Some project 03 task, no priorty
+@con02 +prj04 -- Some project 04 task, no priority
+EOF
+test_todo_session 'plain mode option' <<EOF
+>>> todo.sh ls
+01 (A) @con01 +prj01 -- Some project 01 task, pri A
+02 (A) @con01 +prj02 -- Some project 02 task, pri A
+03 (A) @con02 +prj03 -- Some project 03 task, pri A
+04 (A) @con02 +prj04 -- Some project 04 task, pri A
+05 (B) @con01 +prj01 -- Some project 01 task, pri B
+06 (B) @con01 +prj02 -- Some project 02 task, pri B
+07 (B) @con02 +prj03 -- Some project 03 task, pri B
+08 (B) @con02 +prj04 -- Some project 04 task, pri B
+09 (C) @con01 +prj01 -- Some project 01 task, pri C
+10 (C) @con01 +prj02 -- Some project 02 task, pri C
+11 (C) @con02 +prj03 -- Some project 03 task, pri C
+12 (C) @con02 +prj04 -- Some project 04 task, pri C
+13 (D) @con01 +prj01 -- Some project 01 task, pri D
+14 (D) @con01 +prj02 -- Some project 02 task, pri D
+15 (D) @con02 +prj03 -- Some project 03 task, pri D
+16 (D) @con02 +prj04 -- Some project 04 task, pri D
+17 @con01 +prj01 -- Some project 01 task, no priority
+18 @con01 +prj02 -- Some project 02 task, no priority
+19 @con02 +prj03 -- Some project 03 task, no priorty
+20 @con02 +prj04 -- Some project 04 task, no priority
+--
+TODO: 20 of 20 tasks shown from $HOME/todo.txt
+
+>>> todo.sh -p ls
+01 (A) @con01 +prj01 -- Some project 01 task, pri A
+02 (A) @con01 +prj02 -- Some project 02 task, pri A
+03 (A) @con02 +prj03 -- Some project 03 task, pri A
+04 (A) @con02 +prj04 -- Some project 04 task, pri A
+05 (B) @con01 +prj01 -- Some project 01 task, pri B
+06 (B) @con01 +prj02 -- Some project 02 task, pri B
+07 (B) @con02 +prj03 -- Some project 03 task, pri B
+08 (B) @con02 +prj04 -- Some project 04 task, pri B
+09 (C) @con01 +prj01 -- Some project 01 task, pri C
+10 (C) @con01 +prj02 -- Some project 02 task, pri C
+11 (C) @con02 +prj03 -- Some project 03 task, pri C
+12 (C) @con02 +prj04 -- Some project 04 task, pri C
+13 (D) @con01 +prj01 -- Some project 01 task, pri D
+14 (D) @con01 +prj02 -- Some project 02 task, pri D
+15 (D) @con02 +prj03 -- Some project 03 task, pri D
+16 (D) @con02 +prj04 -- Some project 04 task, pri D
+17 @con01 +prj01 -- Some project 01 task, no priority
+18 @con01 +prj02 -- Some project 02 task, no priority
+19 @con02 +prj03 -- Some project 03 task, no priorty
+20 @con02 +prj04 -- Some project 04 task, no priority
+--
+TODO: 20 of 20 tasks shown from $HOME/todo.txt
+EOF
+
+#
+# check the P,@,+ command line options
+#
+cat > todo.txt <<EOF
+(A) @con01 +prj01 -- Some project 01 task, pri A
+(A) @con01 +prj02 -- Some project 02 task, pri A
+(A) @con02 +prj03 -- Some project 03 task, pri A
+(A) @con02 +prj04 -- Some project 04 task, pri A
+(B) @con01 +prj01 -- Some project 01 task, pri B
+(B) @con01 +prj02 -- Some project 02 task, pri B
+(B) @con02 +prj03 -- Some project 03 task, pri B
+(B) @con02 +prj04 -- Some project 04 task, pri B
+(C) @con01 +prj01 -- Some project 01 task, pri C
+(C) @con01 +prj02 -- Some project 02 task, pri C
+(C) @con02 +prj03 -- Some project 03 task, pri C
+(C) @con02 +prj04 -- Some project 04 task, pri C
+(D) @con01 +prj01 -- Some project 01 task, pri D
+(D) @con01 +prj02 -- Some project 02 task, pri D
+(D) @con02 +prj03 -- Some project 03 task, pri D
+(D) @con02 +prj04 -- Some project 04 task, pri D
+@con01 +prj01 -- Some project 01 task, no priority
+@con01 +prj02 -- Some project 02 task, no priority
+@con02 +prj03 -- Some project 03 task, no priorty
+@con02 +prj04 -- Some project 04 task, no priority
+EOF
+test_todo_session 'context, project, and priority suppression' <<EOF
+>>> todo.sh ls
+01 (A) @con01 +prj01 -- Some project 01 task, pri A
+02 (A) @con01 +prj02 -- Some project 02 task, pri A
+03 (A) @con02 +prj03 -- Some project 03 task, pri A
+04 (A) @con02 +prj04 -- Some project 04 task, pri A
+05 (B) @con01 +prj01 -- Some project 01 task, pri B
+06 (B) @con01 +prj02 -- Some project 02 task, pri B
+07 (B) @con02 +prj03 -- Some project 03 task, pri B
+08 (B) @con02 +prj04 -- Some project 04 task, pri B
+09 (C) @con01 +prj01 -- Some project 01 task, pri C
+10 (C) @con01 +prj02 -- Some project 02 task, pri C
+11 (C) @con02 +prj03 -- Some project 03 task, pri C
+12 (C) @con02 +prj04 -- Some project 04 task, pri C
+13 (D) @con01 +prj01 -- Some project 01 task, pri D
+14 (D) @con01 +prj02 -- Some project 02 task, pri D
+15 (D) @con02 +prj03 -- Some project 03 task, pri D
+16 (D) @con02 +prj04 -- Some project 04 task, pri D
+17 @con01 +prj01 -- Some project 01 task, no priority
+18 @con01 +prj02 -- Some project 02 task, no priority
+19 @con02 +prj03 -- Some project 03 task, no priorty
+20 @con02 +prj04 -- Some project 04 task, no priority
+--
+TODO: 20 of 20 tasks shown from $HOME/todo.txt
+
+>>> todo.sh ls @con01
+01 (A) @con01 +prj01 -- Some project 01 task, pri A
+02 (A) @con01 +prj02 -- Some project 02 task, pri A
+05 (B) @con01 +prj01 -- Some project 01 task, pri B
+06 (B) @con01 +prj02 -- Some project 02 task, pri B
+09 (C) @con01 +prj01 -- Some project 01 task, pri C
+10 (C) @con01 +prj02 -- Some project 02 task, pri C
+13 (D) @con01 +prj01 -- Some project 01 task, pri D
+14 (D) @con01 +prj02 -- Some project 02 task, pri D
+17 @con01 +prj01 -- Some project 01 task, no priority
+18 @con01 +prj02 -- Some project 02 task, no priority
+--
+TODO: 10 of 20 tasks shown from $HOME/todo.txt
+
+>>> todo.sh -P ls @con01
+01 @con01 +prj01 -- Some project 01 task, pri A
+02 @con01 +prj02 -- Some project 02 task, pri A
+05 @con01 +prj01 -- Some project 01 task, pri B
+06 @con01 +prj02 -- Some project 02 task, pri B
+09 @con01 +prj01 -- Some project 01 task, pri C
+10 @con01 +prj02 -- Some project 02 task, pri C
+13 @con01 +prj01 -- Some project 01 task, pri D
+14 @con01 +prj02 -- Some project 02 task, pri D
+17 @con01 +prj01 -- Some project 01 task, no priority
+18 @con01 +prj02 -- Some project 02 task, no priority
+--
+TODO: 10 of 20 tasks shown from $HOME/todo.txt
+
+>>> todo.sh -+ ls @con01
+01 (A) @con01 -- Some project 01 task, pri A
+02 (A) @con01 -- Some project 02 task, pri A
+05 (B) @con01 -- Some project 01 task, pri B
+06 (B) @con01 -- Some project 02 task, pri B
+09 (C) @con01 -- Some project 01 task, pri C
+10 (C) @con01 -- Some project 02 task, pri C
+13 (D) @con01 -- Some project 01 task, pri D
+14 (D) @con01 -- Some project 02 task, pri D
+17 @con01 -- Some project 01 task, no priority
+18 @con01 -- Some project 02 task, no priority
+--
+TODO: 10 of 20 tasks shown from $HOME/todo.txt
+
+>>> todo.sh -@ ls @con01
+01 (A) +prj01 -- Some project 01 task, pri A
+02 (A) +prj02 -- Some project 02 task, pri A
+05 (B) +prj01 -- Some project 01 task, pri B
+06 (B) +prj02 -- Some project 02 task, pri B
+09 (C) +prj01 -- Some project 01 task, pri C
+10 (C) +prj02 -- Some project 02 task, pri C
+13 (D) +prj01 -- Some project 01 task, pri D
+14 (D) +prj02 -- Some project 02 task, pri D
+17 +prj01 -- Some project 01 task, no priority
+18 +prj02 -- Some project 02 task, no priority
+--
+TODO: 10 of 20 tasks shown from $HOME/todo.txt
+
+>>> todo.sh -P -@ ls @con01
+01 +prj01 -- Some project 01 task, pri A
+02 +prj02 -- Some project 02 task, pri A
+05 +prj01 -- Some project 01 task, pri B
+06 +prj02 -- Some project 02 task, pri B
+09 +prj01 -- Some project 01 task, pri C
+10 +prj02 -- Some project 02 task, pri C
+13 +prj01 -- Some project 01 task, pri D
+14 +prj02 -- Some project 02 task, pri D
+17 +prj01 -- Some project 01 task, no priority
+18 +prj02 -- Some project 02 task, no priority
+--
+TODO: 10 of 20 tasks shown from $HOME/todo.txt
+
+>>> todo.sh -P -@ -+ -P -@ -+ ls @con01
+01 (A) @con01 +prj01 -- Some project 01 task, pri A
+02 (A) @con01 +prj02 -- Some project 02 task, pri A
+05 (B) @con01 +prj01 -- Some project 01 task, pri B
+06 (B) @con01 +prj02 -- Some project 02 task, pri B
+09 (C) @con01 +prj01 -- Some project 01 task, pri C
+10 (C) @con01 +prj02 -- Some project 02 task, pri C
+13 (D) @con01 +prj01 -- Some project 01 task, pri D
+14 (D) @con01 +prj02 -- Some project 02 task, pri D
+17 @con01 +prj01 -- Some project 01 task, no priority
+18 @con01 +prj02 -- Some project 02 task, no priority
+--
+TODO: 10 of 20 tasks shown from $HOME/todo.txt
+
+>>> todo.sh -P -@ -+ -P -@ -+ -P -@ -+ ls @con01
+01 -- Some project 01 task, pri A
+02 -- Some project 02 task, pri A
+05 -- Some project 01 task, pri B
+06 -- Some project 02 task, pri B
+09 -- Some project 01 task, pri C
+10 -- Some project 02 task, pri C
+13 -- Some project 01 task, pri D
+14 -- Some project 02 task, pri D
+17 -- Some project 01 task, no priority
+18 -- Some project 02 task, no priority
+--
+TODO: 10 of 20 tasks shown from $HOME/todo.txt
+EOF
+
+#
+# check the line number padding
+#
+cat > todo.txt <<EOF
+hex00 this is one line
+hex01 this is another line
+hex02 this is another line
+hex03 this is another line
+hex04 this is another line
+hex05 this is another line
+hex06 this is another line
+hex07 this is another line
+hex08 this is another line
+hex09 this is another line
+hex0A this is another line
+hex0B this is another line
+hex0C this is another line
+hex0D this is another line
+hex0E this is another line
+hex0F this is another line
+hex10 this is line is a multiple of 16
+hex11 this is another line
+hex12 this is another line
+hex13 this is another line
+hex14 this is another line
+hex15 this is another line
+hex16 this is another line
+hex17 this is another line
+hex18 this is another line
+hex19 this is another line
+hex1A this is another line
+hex1B this is another line
+hex1C this is another line
+hex1D this is another line
+hex1E this is another line
+hex1F this is another line
+hex20 this is line is a multiple of 16
+hex21 this is another line
+hex22 this is another line
+hex23 this is another line
+hex24 this is another line
+hex25 this is another line
+hex26 this is another line
+hex27 this is another line
+hex28 this is another line
+hex29 this is another line
+hex2A this is another line
+hex2B this is another line
+hex2C this is another line
+hex2D this is another line
+hex2E this is another line
+hex2F this is another line
+hex30 this is line is a multiple of 16
+hex31 this is another line
+hex32 this is another line
+hex33 this is another line
+hex34 this is another line
+hex35 this is another line
+hex36 this is another line
+hex37 this is another line
+hex38 this is another line
+hex39 this is another line
+hex3A this is another line
+hex3B this is another line
+hex3C this is another line
+hex3D this is another line
+hex3E this is another line
+hex3F this is another line
+hex40 this is line is a multiple of 16
+hex41 this is another line
+hex42 this is another line
+hex43 this is another line
+hex44 this is another line
+hex45 this is another line
+hex46 this is another line
+hex47 this is another line
+hex48 this is another line
+hex49 this is another line
+hex4A this is another line
+hex4B this is another line
+hex4C this is another line
+hex4D this is another line
+hex4E this is another line
+hex4F this is another line
+hex50 this is line is a multiple of 16
+hex51 this is another line
+hex52 this is another line
+hex53 this is another line
+hex54 this is another line
+hex55 this is another line
+hex56 this is another line
+hex57 this is another line
+hex58 this is another line
+hex59 this is another line
+hex5A this is another line
+hex5B this is another line
+hex5C this is another line
+hex5D this is another line
+hex5E this is another line
+hex5F this is another line
+hex60 this is line is a multiple of 16
+hex61 this is another line
+hex62 this is another line
+hex63 this is another line
+hex64 this is another line
+hex65 this is another line
+hex66 this is another line
+hex67 this is another line
+hex68 this is another line
+hex69 this is another line
+hex6A this is another line
+hex6B this is another line
+hex6C this is another line
+hex6D this is another line
+hex6E this is another line
+hex6F this is another line
+EOF
+test_todo_session 'check line number padding, out to 3 digits' <<EOF
+>>> todo.sh ls
+001 hex00 this is one line
+002 hex01 this is another line
+003 hex02 this is another line
+004 hex03 this is another line
+005 hex04 this is another line
+006 hex05 this is another line
+007 hex06 this is another line
+008 hex07 this is another line
+009 hex08 this is another line
+010 hex09 this is another line
+011 hex0A this is another line
+012 hex0B this is another line
+013 hex0C this is another line
+014 hex0D this is another line
+015 hex0E this is another line
+016 hex0F this is another line
+017 hex10 this is line is a multiple of 16
+018 hex11 this is another line
+019 hex12 this is another line
+020 hex13 this is another line
+021 hex14 this is another line
+022 hex15 this is another line
+023 hex16 this is another line
+024 hex17 this is another line
+025 hex18 this is another line
+026 hex19 this is another line
+027 hex1A this is another line
+028 hex1B this is another line
+029 hex1C this is another line
+030 hex1D this is another line
+031 hex1E this is another line
+032 hex1F this is another line
+033 hex20 this is line is a multiple of 16
+034 hex21 this is another line
+035 hex22 this is another line
+036 hex23 this is another line
+037 hex24 this is another line
+038 hex25 this is another line
+039 hex26 this is another line
+040 hex27 this is another line
+041 hex28 this is another line
+042 hex29 this is another line
+043 hex2A this is another line
+044 hex2B this is another line
+045 hex2C this is another line
+046 hex2D this is another line
+047 hex2E this is another line
+048 hex2F this is another line
+049 hex30 this is line is a multiple of 16
+050 hex31 this is another line
+051 hex32 this is another line
+052 hex33 this is another line
+053 hex34 this is another line
+054 hex35 this is another line
+055 hex36 this is another line
+056 hex37 this is another line
+057 hex38 this is another line
+058 hex39 this is another line
+059 hex3A this is another line
+060 hex3B this is another line
+061 hex3C this is another line
+062 hex3D this is another line
+063 hex3E this is another line
+064 hex3F this is another line
+065 hex40 this is line is a multiple of 16
+066 hex41 this is another line
+067 hex42 this is another line
+068 hex43 this is another line
+069 hex44 this is another line
+070 hex45 this is another line
+071 hex46 this is another line
+072 hex47 this is another line
+073 hex48 this is another line
+074 hex49 this is another line
+075 hex4A this is another line
+076 hex4B this is another line
+077 hex4C this is another line
+078 hex4D this is another line
+079 hex4E this is another line
+080 hex4F this is another line
+081 hex50 this is line is a multiple of 16
+082 hex51 this is another line
+083 hex52 this is another line
+084 hex53 this is another line
+085 hex54 this is another line
+086 hex55 this is another line
+087 hex56 this is another line
+088 hex57 this is another line
+089 hex58 this is another line
+090 hex59 this is another line
+091 hex5A this is another line
+092 hex5B this is another line
+093 hex5C this is another line
+094 hex5D this is another line
+095 hex5E this is another line
+096 hex5F this is another line
+097 hex60 this is line is a multiple of 16
+098 hex61 this is another line
+099 hex62 this is another line
+100 hex63 this is another line
+101 hex64 this is another line
+102 hex65 this is another line
+103 hex66 this is another line
+104 hex67 this is another line
+105 hex68 this is another line
+106 hex69 this is another line
+107 hex6A this is another line
+108 hex6B this is another line
+109 hex6C this is another line
+110 hex6D this is another line
+111 hex6E this is another line
+112 hex6F this is another line
+--
+TODO: 112 of 112 tasks shown from $HOME/todo.txt
+EOF
+
+test_done

todo.cfg

@@ -52,4 +52,15 @@ export TMP_FILE="$TODO_DIR/todo.tmp"
 # === BEHAVIOR ===
 
 ## customize list output
+#
+# TODOTXT_SORT_COMMAND will filter after line numbers are
+# inserted, but before colorization, and before hiding of
+# priority, context, and project.
+#
 # export TODOTXT_SORT_COMMAND='env LC_COLLATE=C sort -f -k2'
+
+# TODOTXT_FINAL_FILTER will filter list output after colorization,
+# priority hiding, context hiding, and project hiding. That is,
+# just before the list output is displayed.
+#
+# export TODOTXT_FINAL_FILTER='cat'

todo.sh

@@ -208,6 +208,7 @@ help()
         TODOTXT_VERBOSE=1               is same as option -v
         TODOTXT_DEFAULT_ACTION=""       run this when called with no arguments
         TODOTXT_SORT_COMMAND="sort ..." customize list output
+        TODOTXT_FINAL_FILTER="sed ..."  customize list after color, P@+ hiding
 EndHelp
 
     if [ -d "$TODO_ACTIONS_DIR" ]
@@ -347,8 +348,9 @@ TODOTXT_AUTO_ARCHIVE=${TODOTXT_AUTO_ARCHIVE:-1}
 TODOTXT_DATE_ON_ADD=${TODOTXT_DATE_ON_ADD:-0}
 TODOTXT_DEFAULT_ACTION=${TODOTXT_DEFAULT_ACTION:-}
 TODOTXT_SORT_COMMAND=${TODOTXT_SORT_COMMAND:-env LC_COLLATE=C sort -f -k2}
+TODOTXT_FINAL_FILTER=${TODOTXT_FINAL_FILTER:-cat}
 
-export TODOTXT_VERBOSE TODOTXT_PLAIN TODOTXT_CFG_FILE TODOTXT_FORCE TODOTXT_PRESERVE_LINE_NUMBERS TODOTXT_AUTO_ARCHIVE TODOTXT_DATE_ON_ADD TODOTXT_SORT_COMMAND
+export TODOTXT_VERBOSE TODOTXT_PLAIN TODOTXT_CFG_FILE TODOTXT_FORCE TODOTXT_PRESERVE_LINE_NUMBERS TODOTXT_AUTO_ARCHIVE TODOTXT_DATE_ON_ADD TODOTXT_SORT_COMMAND TODOTXT_FINAL_FILTER
 
 # Default color map
 export NONE=''
@@ -509,6 +511,7 @@ _list() {
             s/'${HIDE_PROJECTS_SUBSTITUTION:-^}'//g
             s/'${HIDE_CONTEXTS_SUBSTITUTION:-^}'//g
           '''                                                   \
+        | eval ${TODOTXT_FINAL_FILTER}                          \
     )
     echo -ne "$filtered_items${filtered_items:+\n}"