Add HIDE_CUSTOM_SUBSTITUTION for customization and add-ons.

Add-ons or users may want to hide parts of the task text from the output.
Though this can already be solved through TODOTXT_FINAL_FILTER, augmenting the configured value is not trivial, and it introduces another SED command into the already long _list() pipeline. Putting an additional HIDE_CUSTOM_SUBSTITUTION into the existing pipeline has hardly any performance implications, and makes the realization of this use case trivial.

Makefile

@@ -13,7 +13,7 @@ VERSION-FILE: .FORCE-VERSION-FILE
 todo.sh: VERSION-FILE
 
 # For packaging
-DISTFILES := todo.cfg
+DISTFILES := todo.cfg todo_completion
 
 DISTNAME=todo.txt_cli-$(VERSION)
 dist: $(DISTFILES) todo.sh

tests/t0100-code-nobacktick.sh

@@ -0,0 +1,16 @@
+#!/bin/sh
+
+test_description='no old-style backtick command substitution
+
+This test checks the todo.sh script itself for occurrences
+of old-style backtick command substitution, which should be
+replaced with $(...).
+On failure, it will print each offending line number and line.
+'
+. ./test-lib.sh
+
+test_todo_session 'no old-style backtick command substitution' <<EOF
+>>> sed -n -e 's/\(^\|[ \t]\)#.*//' -e '/\`/{' -e '=;p' -e '}' "$(which todo.sh)"
+EOF
+
+test_done

tests/t1000-addlist.sh

@@ -77,4 +77,37 @@ TODO: 5 added.
 TODO: 5 of 5 tasks shown
 EOF
 
+#
+# Advanced add
+#
+
+cat /dev/null > todo.txt
+test_todo_session 'add with spaces' <<EOF
+>>> todo.sh add "notice the   three   spaces"
+1 notice the   three   spaces
+TODO: 1 added.
+
+>>> todo.sh add notice how the   spaces    get lost
+2 notice how the spaces get lost
+TODO: 2 added.
+
+>>> todo.sh list
+2 notice how the spaces get lost
+1 notice the   three   spaces
+--
+TODO: 2 of 2 tasks shown
+EOF
+
+cat /dev/null > todo.txt
+test_todo_session 'add with CR' <<EOF
+>>> todo.sh add "smell the
+Carriage Return"
+1 smell the Carriage Return
+TODO: 1 added.
+
+>>> todo.sh list
+1 smell the Carriage Return
+--
+TODO: 1 of 1 tasks shown
+EOF
 

tests/t1010-add-date.sh

@@ -21,6 +21,22 @@ TODO: 1 added.
 TODO: 1 of 1 tasks shown
 EOF
 
+test_todo_session 'cmd line first day with priority' <<EOF
+>>> todo.sh -pt add '(A) notice the daisies'
+2 (A) 2009-02-13 notice the daisies
+TODO: 2 added.
+
+>>> todo.sh -p list
+2 (A) 2009-02-13 notice the daisies
+1 2009-02-13 notice the daisies
+--
+TODO: 2 of 2 tasks shown
+
+>>> todo.sh -npf del 2
+2 (A) 2009-02-13 notice the daisies
+TODO: 2 deleted.
+EOF
+
 test_tick
 
 test_todo_session 'cmd line second day' <<EOF

tests/t1020-addtolistfile.sh

@@ -39,6 +39,24 @@ GARDEN: 2 added.
 GARDEN: 2 of 2 tasks shown
 EOF
 
+#
+# List available files
+#
+test_todo_session 'list available files' <<EOF
+>>> todo.sh listfile
+Files in the todo.txt directory:
+done.txt
+garden.txt
+report.txt
+todo.txt
+
+>>> TODOTXT_VERBOSE=0 todo.sh listfile
+done.txt
+garden.txt
+report.txt
+todo.txt
+EOF
+
 #
 # Filter
 #

tests/t1100-replace.sh

@@ -45,6 +45,12 @@ grow some corn
 thrash some hay
 chase the chickens
 EOF
+test_todo_session 'replace error' << EOF
+>>> todo.sh replace 10 "hej!"
+=== 1
+TODO: No task 10.
+EOF
+
 test_todo_session 'replace in multi-item file' <<EOF
 >>> todo.sh replace 1 smell the cheese
 1 smell the cows
@@ -62,33 +68,59 @@ TODO: Replaced task with:
 4 collect the eggs
 EOF
 
+echo '(A) collect the eggs' > todo.txt
 test_todo_session 'replace with priority' <<EOF
->>> todo.sh pri 4 a
+>>> todo.sh replace 1 "collect the bread"
-4 (A) collect the eggs
+1 (A) collect the eggs
-TODO: 4 prioritized (A).
-
->>> todo.sh replace 4 "collect the bread"
-4 (A) collect the eggs
 TODO: Replaced task with:
-4 (A) collect the bread
+1 (A) collect the bread
 
->>> todo.sh replace 4 collect the eggs
+>>> todo.sh replace 1 collect the eggs
-4 (A) collect the bread
+1 (A) collect the bread
 TODO: Replaced task with:
-4 (A) collect the eggs
+1 (A) collect the eggs
 EOF
 
+echo 'jump on hay' > todo.txt
 test_todo_session 'replace with &' << EOF
->>> todo.sh replace 3 "thrash the hay & thresh the wheat"
+>>> todo.sh replace 1 "thrash the hay & thrash the wheat"
-3 jump on hay
+1 jump on hay
 TODO: Replaced task with:
-3 thrash the hay & thresh the wheat
+1 thrash the hay & thrash the wheat
 EOF
 
-test_todo_session 'replace error' << EOF
+echo 'jump on hay' > todo.txt
->>> todo.sh replace 10 "hej!"
+test_todo_session 'replace with spaces' <<EOF
-=== 1
+>>> todo.sh replace 1 "notice the   three   spaces"
-TODO: No task 10.
+1 jump on hay
+TODO: Replaced task with:
+1 notice the   three   spaces
+EOF
+
+cat > todo.txt <<EOF
+smell the cows
+grow some corn
+thrash some hay
+chase the chickens
+EOF
+test_todo_session 'replace with symbols' <<EOF
+>>> todo.sh replace 1 "~@#$%^&*()-_=+[{]}|;:',<.>/?"
+1 smell the cows
+TODO: Replaced task with:
+1 ~@#$%^&*()-_=+[{]}|;:',<.>/?
+
+>>> todo.sh replace 2 '\`!\\"'
+2 grow some corn
+TODO: Replaced task with:
+2 \`!\\"
+
+>>> todo.sh list
+4 chase the chickens
+3 thrash some hay
+2 \`!\\"
+1 ~@#$%^&*()-_=+[{]}|;:',<.>/?
+--
+TODO: 4 of 4 tasks shown
 EOF
 
 cat /dev/null > todo.txt
@@ -124,6 +156,7 @@ TODO: Replaced task with:
 1 (A) 2009-02-13 this is just a new one
 EOF
 
+echo '(A) 2009-02-13 this is just a new one' > todo.txt
 test_todo_session 'replace with prepended date replaces existing date' <<EOF
 >>> todo.sh replace 1 2010-07-04 this also has a new date
 1 (A) 2009-02-13 this is just a new one

tests/t1200-pri.sh

@@ -53,9 +53,34 @@ TODO: 2 prioritized (C).
 --
 TODO: 3 of 3 tasks shown
 
+>>> todo.sh add "smell the coffee +wakeup"
+4 smell the coffee +wakeup
+TODO: 4 added.
+
+>>> todo.sh -p list
+1 (B) smell the uppercase Roses +flowers @outside
+2 (C) notice the sunflowers
+4 smell the coffee +wakeup
+3 stop
+--
+TODO: 4 of 4 tasks shown
+EOF
+
+test_todo_session 'priority error' <<EOF
+>>> todo.sh pri 10 B
+=== 1
+TODO: No task 10.
+EOF
+
+cat > todo.txt <<EOF
+(B) smell the uppercase Roses +flowers @outside
+(C) notice the sunflowers
+stop
+EOF
+test_todo_session 'reprioritize' <<EOF
 >>> todo.sh pri 2 A
 2 (A) notice the sunflowers
-TODO: 2 prioritized (A).
+TODO: 2 re-prioritized from (C) to (A).
 
 >>> todo.sh -p list
 2 (A) notice the sunflowers
@@ -66,25 +91,13 @@ TODO: 3 of 3 tasks shown
 
 >>> todo.sh pri 2 a
 2 (A) notice the sunflowers
-TODO: 2 prioritized (A).
+TODO: 2 already prioritized (A).
-
->>> todo.sh -p listpri
-2 (A) notice the sunflowers
-1 (B) smell the uppercase Roses +flowers @outside
---
-TODO: 2 of 3 tasks shown
-
->>> todo.sh add "smell the coffee +wakeup"
-4 smell the coffee +wakeup
-TODO: 4 added.
 
 >>> todo.sh -p list
 2 (A) notice the sunflowers
 1 (B) smell the uppercase Roses +flowers @outside
-4 smell the coffee +wakeup
 3 stop
 --
-TODO: 4 of 4 tasks shown
+TODO: 3 of 3 tasks shown
 EOF
-
 test_done

tests/t1250-listpri.sh

@@ -0,0 +1,95 @@
+#!/bin/sh
+
+test_description='list priority functionality
+'
+. ./test-lib.sh
+
+cat > todo.txt <<EOF
+(B) smell the uppercase Roses +flowers @outside
+(C) notice the sunflowers
+stop
+EOF
+test_todo_session 'basic listpri' <<EOF
+>>> todo.sh listpri A
+--
+TODO: 0 of 3 tasks shown
+
+>>> todo.sh -p listpri c
+2 (C) notice the sunflowers
+--
+TODO: 1 of 3 tasks shown
+EOF
+
+test_todo_session 'listpri highlighting' <<EOF
+>>> todo.sh listpri
+1 (B) smell the uppercase Roses +flowers @outside
+2 (C) notice the sunflowers
+--
+TODO: 2 of 3 tasks shown
+EOF
+
+cat > todo.txt <<EOF
+(B) smell the uppercase Roses +flowers @outside
+(C) notice the sunflowers
+(m)others will notice this
+(n) not a prioritized task
+notice the (C)opyright
+EOF
+test_todo_session 'listpri filtering priorities' <<EOF
+>>> todo.sh -p listpri
+1 (B) smell the uppercase Roses +flowers @outside
+2 (C) notice the sunflowers
+--
+TODO: 2 of 5 tasks shown
+
+>>> todo.sh -p listpri b
+1 (B) smell the uppercase Roses +flowers @outside
+--
+TODO: 1 of 5 tasks shown
+
+>>> todo.sh -p listpri c
+2 (C) notice the sunflowers
+--
+TODO: 1 of 5 tasks shown
+
+>>> todo.sh -p listpri m
+--
+TODO: 0 of 5 tasks shown
+
+>>> todo.sh -p listpri n
+--
+TODO: 0 of 5 tasks shown
+EOF
+
+cat > todo.txt <<EOF
+(B) ccc xxx this line should be third.
+ccc xxx this line should be third.
+(A) aaa zzz this line should be first.
+aaa zzz this line should be first.
+(B) bbb yyy this line should be second.
+bbb yyy this line should be second.
+EOF
+test_todo_session 'listpri filtering of TERM' <<EOF
+>>> todo.sh -p listpri "should be"
+3 (A) aaa zzz this line should be first.
+5 (B) bbb yyy this line should be second.
+1 (B) ccc xxx this line should be third.
+--
+TODO: 3 of 6 tasks shown
+
+>>> todo.sh -p listpri a "should be"
+3 (A) aaa zzz this line should be first.
+--
+TODO: 1 of 6 tasks shown
+
+>>> todo.sh -p listpri b second
+5 (B) bbb yyy this line should be second.
+--
+TODO: 1 of 6 tasks shown
+
+>>> todo.sh -p listpri x "should be"
+--
+TODO: 0 of 6 tasks shown
+EOF
+
+test_done

tests/t1260-listprj.sh

@@ -0,0 +1,42 @@
+#!/bin/sh
+
+test_description='list project functionality
+'
+. ./test-lib.sh
+
+cat > todo.txt <<EOF
+(B) smell the uppercase Roses +roses @outside +shared
+(C) notice the sunflowers +sunflowers @garden +shared +landscape
+stop
+EOF
+test_todo_session 'basic listproj' <<EOF
+>>> todo.sh listproj
++landscape
++roses
++shared
++sunflowers
+EOF
+
+test_todo_session 'listproj with context' <<EOF
+>>> todo.sh listproj @garden
++landscape
++shared
++sunflowers
+EOF
+
+TEST_TODO_CUSTOM=todo-custom.cfg
+cat todo.cfg > "$TEST_TODO_CUSTOM"
+cat >> "$TEST_TODO_CUSTOM" <<'EOF'
+export DEFAULT='</color>'
+export PRI_B='<color type=green>'
+export PRI_C='<color type=blue>'
+export TODOTXT_FINAL_FILTER='grep -i roses'
+EOF
+test_todo_session 'listproj with context special cases' <<EOF
+>>> todo.sh -+ -d "$TEST_TODO_CUSTOM" listproj @garden
++landscape
++shared
++sunflowers
+EOF
+
+test_done

tests/t1300-ls.sh

@@ -53,6 +53,18 @@ test_todo_session 'checking TODOTXT_FINAL_FILTER' <<EOF
 TODO: 3 of 3 tasks shown
 EOF
 
+#
+# check the custom hiding
+#
+test_todo_session 'checking HIDE_CUSTOM_SUBSTITUTION' <<EOF
+>>> HIDE_CUSTOM_SUBSTITUTION='[tT]h' todo.sh ls
+2 aaa zzz is line should be first.
+3 bbb yyy is line should be second.
+1 ccc xxx is line should be ird.
+--
+TODO: 3 of 3 tasks shown
+EOF
+
 #
 # check the filtering of TERM
 #
@@ -73,6 +85,29 @@ TODO: 1 of 3 tasks shown
 TODO: 1 of 3 tasks shown
 EOF
 
+#
+# check negative filtering via -TERM
+#
+test_todo_session 'checking negative filtering via -TERM' <<EOF
+>>> todo.sh ls -second
+2 aaa zzz this line should be first.
+1 ccc xxx this line should be third.
+--
+TODO: 2 of 3 tasks shown
+
+>>> todo.sh ls "-should be f"
+3 bbb yyy this line should be second.
+1 ccc xxx this line should be third.
+--
+TODO: 2 of 3 tasks shown
+
+>>> todo.sh ls "- zzz"
+3 bbb yyy this line should be second.
+1 ccc xxx this line should be third.
+--
+TODO: 2 of 3 tasks shown
+EOF
+
 #
 # check the filtering of TERM with regexp
 #
@@ -94,6 +129,40 @@ TODO: 1 of 3 tasks shown
 TODO: 1 of 3 tasks shown
 EOF
 
+#
+# check the filtering of TERM containing characters that are special to the
+# shell, like variables, quotes, and multiple subsequent spaces.
+#
+cat > todo.txt <<'EOF'
+earn some pennies
+earn some $$
+earn some "money"
+get money from O'Brian
+just get   money!
+EOF
+test_todo_session 'checking filtering of special characters' <<'EOF'
+>>> todo.sh ls '$$'
+2 earn some $$
+--
+TODO: 1 of 5 tasks shown
+
+>>> todo.sh ls '"money"'
+3 earn some "money"
+--
+TODO: 1 of 5 tasks shown
+
+>>> todo.sh ls "O'Brian"
+4 get money from O'Brian
+--
+TODO: 1 of 5 tasks shown
+
+>>> todo.sh ls "get   money"
+5 just get   money!
+--
+TODO: 1 of 5 tasks shown
+EOF
+
+
 #
 # check the x command line option
 #
@@ -142,7 +211,7 @@ cat > todo.txt <<EOF
 (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
+@con01 +prj02 -- Some project(S) 02 task, no priority
 @con02 +prj03 -- Some project 03 task, no priorty
 @con02 +prj04 -- Some project 04 task, no priority
 EOF
@@ -165,7 +234,7 @@ test_todo_session 'plain mode option' <<EOF
 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
+18 @con01 +prj02 -- Some project(S) 02 task, no priority
 19 @con02 +prj03 -- Some project 03 task, no priorty
 20 @con02 +prj04 -- Some project 04 task, no priority
 --
@@ -189,7 +258,7 @@ TODO: 20 of 20 tasks shown
 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
+18 @con01 +prj02 -- Some project(S) 02 task, no priority
 19 @con02 +prj03 -- Some project 03 task, no priorty
 20 @con02 +prj04 -- Some project 04 task, no priority
 --
@@ -217,7 +286,7 @@ cat > todo.txt <<EOF
 (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
+@con01 +prj02 -- Some project(S) 02 task, no priority
 @con02 +prj03 -- Some project 03 task, no priorty
 @con02 +prj04 -- Some project 04 task, no priority
 EOF
@@ -240,7 +309,7 @@ test_todo_session 'context, project, and priority suppression' <<EOF
 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
+18 @con01 +prj02 -- Some project(S) 02 task, no priority
 19 @con02 +prj03 -- Some project 03 task, no priorty
 20 @con02 +prj04 -- Some project 04 task, no priority
 --
@@ -256,7 +325,7 @@ TODO: 20 of 20 tasks shown
 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
+18 @con01 +prj02 -- Some project(S) 02 task, no priority
 --
 TODO: 10 of 20 tasks shown
 
@@ -270,7 +339,7 @@ TODO: 10 of 20 tasks shown
 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
+18 @con01 +prj02 -- Some project(S) 02 task, no priority
 --
 TODO: 10 of 20 tasks shown
 
@@ -284,7 +353,7 @@ TODO: 10 of 20 tasks shown
 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
+18 @con01 -- Some project(S) 02 task, no priority
 --
 TODO: 10 of 20 tasks shown
 
@@ -298,7 +367,7 @@ TODO: 10 of 20 tasks shown
 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
+18 +prj02 -- Some project(S) 02 task, no priority
 --
 TODO: 10 of 20 tasks shown
 
@@ -312,7 +381,7 @@ TODO: 10 of 20 tasks shown
 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
+18 +prj02 -- Some project(S) 02 task, no priority
 --
 TODO: 10 of 20 tasks shown
 
@@ -326,7 +395,7 @@ TODO: 10 of 20 tasks shown
 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
+18 @con01 +prj02 -- Some project(S) 02 task, no priority
 --
 TODO: 10 of 20 tasks shown
 
@@ -340,7 +409,7 @@ TODO: 10 of 20 tasks shown
 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
+18 -- Some project(S) 02 task, no priority
 --
 TODO: 10 of 20 tasks shown
 EOF

tests/t1330-ls-highlighting.sh

@@ -166,4 +166,20 @@ test_todo_session 'highlighting with hidden contexts/projects' <<EOF
 TODO: 4 of 4 tasks shown
 EOF
 
+# check that priorities are only matched at the start of the task
+#
+cat > todo.txt <<EOF
+(D) some prioritized task
+not prioritized
+should not be seen as PRIORITIZE(D) task
+EOF
+test_todo_session 'highlighting priority position' <<EOF
+>>> todo.sh ls
+1 (D) some prioritized task
+2 not prioritized
+3 should not be seen as PRIORITIZE(D) task
+--
+TODO: 3 of 3 tasks shown
+EOF
+
 test_done

tests/t1400-prepend.sh

@@ -57,6 +57,34 @@ test_todo_session 'prepend with &' <<EOF
 3 no running & jumping now stop
 EOF
 
+echo 'jump on hay' > todo.txt
+test_todo_session 'prepend with spaces' <<EOF
+>>> todo.sh prepend 1 "notice the   three   spaces and"
+1 notice the   three   spaces and jump on hay
+EOF
+
+cat > todo.txt <<EOF
+smell the cows
+grow some corn
+thrash some hay
+chase the chickens
+EOF
+test_todo_session 'prepend with symbols' <<EOF
+>>> todo.sh prepend 1 "~@#$%^&*()-_=+[{]}|;:',<.>/?"
+1 ~@#$%^&*()-_=+[{]}|;:',<.>/? smell the cows
+
+>>> todo.sh prepend 2 '\`!\\"'
+2 \`!\\" grow some corn
+
+>>> todo.sh list
+4 chase the chickens
+3 thrash some hay
+2 \`!\\" grow some corn
+1 ~@#$%^&*()-_=+[{]}|;:',<.>/? smell the cows
+--
+TODO: 4 of 4 tasks shown
+EOF
+
 cat /dev/null > todo.txt
 test_todo_session 'prepend handling prepended date on add' <<EOF
 >>> todo.sh -t add "new task"

tests/t1500-do.sh

@@ -81,6 +81,6 @@ test_todo_session 'fail multiple do attempts' <<EOF
 TODO: 3 marked as done.
 
 >>> todo.sh -a do 3
-3 is already marked done
+TODO: 3 is already marked done.
 EOF
 test_done

tests/t1600-append.sh

@@ -17,6 +17,12 @@ test_todo_session 'append usage' <<EOF
 usage: todo.sh append ITEM# "TEXT TO APPEND"
 EOF
 
+test_todo_session 'append error' << EOF
+>>> todo.sh append 10 "hej!"
+=== 1
+TODO: No task 10.
+EOF
+
 test_todo_session 'basic append' <<EOF
 >>> todo.sh append 1 "smell the roses"
 1 notice the daisies smell the roses
@@ -37,11 +43,32 @@ test_todo_session 'basic append with &' <<EOF
 TODO: 1 of 1 tasks shown
 EOF
 
+echo 'jump on hay' > todo.txt
+test_todo_session 'append with spaces' <<EOF
+>>> todo.sh append 1 "and notice the   three   spaces"
+1 jump on hay and notice the   three   spaces
+EOF
 
-test_todo_session 'append error' << EOF
+cat > todo.txt <<EOF
->>> todo.sh append 10 "hej!"
+smell the cows
-=== 1
+grow some corn
-TODO: No task 10.
+thrash some hay
+chase the chickens
+EOF
+test_todo_session 'append with symbols' <<EOF
+>>> todo.sh append 1 "~@#$%^&*()-_=+[{]}|;:',<.>/?"
+1 smell the cows ~@#$%^&*()-_=+[{]}|;:',<.>/?
+
+>>> todo.sh append 2 '\`!\\"'
+2 grow some corn \`!\\"
+
+>>> todo.sh list
+4 chase the chickens
+2 grow some corn \`!\\"
+1 smell the cows ~@#$%^&*()-_=+[{]}|;:',<.>/?
+3 thrash some hay
+--
+TODO: 4 of 4 tasks shown
 EOF
 
 cat > todo.txt <<EOF

todo.sh

@@ -1,7 +1,7 @@
 #! /bin/bash
 
 # === HEAVY LIFTING ===
-shopt -s extglob
+shopt -s extglob extquote
 
 # NOTE:  Todo.sh requires the .todo/config configuration file to run.
 # Place the .todo/config file in your home directory or use the -d option for a custom location.
@@ -44,39 +44,113 @@ shorthelp()
 
 		  Actions:
 		    add|a "THING I NEED TO DO +project @context"
-		    addto DEST "TEXT TO ADD"
 		    addm "THINGS I NEED TO DO
 		          MORE THINGS I NEED TO DO"
+		    addto DEST "TEXT TO ADD"
 		    append|app ITEM# "TEXT TO APPEND"
 		    archive
 		    command [ACTIONS]
 		    del|rm ITEM# [TERM]
-		    dp|depri ITEM#[, ITEM#, ITEM#, ...]
+		    depri|dp ITEM#[, ITEM#, ITEM#, ...]
 		    do ITEM#[, ITEM#, ITEM#, ...]
 		    help
 		    list|ls [TERM...]
 		    listall|lsa [TERM...]
 		    listcon|lsc
-		    listfile|lf SRC [TERM...]
+		    listfile|lf [SRC [TERM...]]
-		    listpri|lsp [PRIORITY]
+		    listpri|lsp [PRIORITY] [TERM...]
-		    listproj|lsprj
+		    listproj|lsprj [TERM...]
 		    move|mv ITEM# DEST [SRC]
 		    prepend|prep ITEM# "TEXT TO PREPEND"
 		    pri|p ITEM# PRIORITY
 		    replace ITEM# "UPDATED TODO"
 		    report
+		    shorthelp
+
+	EndHelp
+
+    # Only list the one-line usage from the add-on actions. This assumes that
+    # add-ons use the same usage indentation structure as todo.sh.
+    addonHelp | grep -e '^  Add-on Actions:' -e '^    [[:alpha:]]'
+
+    cat <<-EndHelpFooter
 
 		  See "help" for more details.
-	EndHelp
+	EndHelpFooter
     exit 0
 }
 
 help()
 {
-    cat <<-EndHelp
+    cat <<-EndOptionsHelp
 		  Usage: $oneline_usage
 
-		  Actions:
+		  Options:
+		    -@
+		        Hide context names in list output. Use twice to show context
+		        names (default).
+		    -+
+		        Hide project names in list output. Use twice to show project
+		        names (default).
+		    -c
+		        Color mode
+		    -d CONFIG_FILE
+		        Use a configuration file other than the default ~/.todo/config
+		    -f
+		        Forces actions without confirmation or interactive input
+		    -h
+		        Display a short help message; same as action "shorthelp"
+		    -p
+		        Plain mode turns off colors
+		    -P
+		        Hide priority labels in list output. Use twice to show
+		        priority labels (default).
+		    -a
+		        Don't auto-archive tasks automatically on completion
+		    -A
+		        Auto-archive tasks automatically on completion
+		    -n
+		        Don't preserve line numbers; automatically remove blank lines
+		        on task deletion
+		    -N
+		        Preserve line numbers
+		    -t
+		        Prepend the current date to a task automatically
+		        when it's added.
+		    -T
+		        Do not prepend the current date to a task automatically
+		        when it's added.
+		    -v
+		        Verbose mode turns on confirmation messages
+		    -vv
+		        Extra verbose mode prints some debugging information and
+		        additional help text
+		    -V
+		        Displays version, license and credits
+		    -x
+		        Disables TODOTXT_FINAL_FILTER
+
+
+	EndOptionsHelp
+
+    [ $TODOTXT_VERBOSE -gt 1 ] && cat <<-EndVerboseHelp
+		  Environment variables:
+		    TODOTXT_AUTO_ARCHIVE            is same as option -a (0)/-A (1)
+		    TODOTXT_CFG_FILE=CONFIG_FILE    is same as option -d CONFIG_FILE
+		    TODOTXT_FORCE=1                 is same as option -f
+		    TODOTXT_PRESERVE_LINE_NUMBERS   is same as option -n (0)/-N (1)
+		    TODOTXT_PLAIN                   is same as option -p (1)/-c (0)
+		    TODOTXT_DATE_ON_ADD             is same as option -t (1)/-T (0)
+		    TODOTXT_VERBOSE=1               is same as option -v
+		    TODOTXT_DISABLE_FILTER=1        is same as option -x
+		    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
+
+
+	EndVerboseHelp
+    cat <<-EndActionsHelp
+		  Built-in Actions:
 		    add "THING I NEED TO DO +project @context"
 		    a "THING I NEED TO DO +project @context"
 		      Adds THING I NEED TO DO to your todo.txt file on its own line.
@@ -137,16 +211,19 @@ help()
 		    lsc
 		      Lists all the task contexts that start with the @ sign in todo.txt.
 
-		    listfile SRC [TERM...]
+		    listfile [SRC [TERM...]]
-		    lf SRC [TERM...]
+		    lf [SRC [TERM...]]
 		      Displays all the lines in SRC file located in the todo.txt directory,
 		      sorted by priority with line  numbers.  If TERM specified, lists
 		      all lines that contain TERM in SRC file.
+		      Without any arguments, the names of all text files in the todo.txt
+		      directory are listed.
 
-		    listpri [PRIORITY]
+		    listpri [PRIORITY] [TERM...]
-		    lsp [PRIORITY]
+		    lsp [PRIORITY] [TERM...]
 		      Displays all tasks prioritized PRIORITY.
 		      If no PRIORITY specified, lists all prioritized tasks.
+		      If TERM specified, lists only prioritized tasks that contain TERM.
 
 		    listproj
 		    lsprj
@@ -176,81 +253,33 @@ help()
 		    report
 		      Adds the number of open tasks and done tasks to report.txt.
 
+		    shorthelp
+		      List the one-line usage of all built-in and add-on actions.
 
 
-		  Options:
+	EndActionsHelp
-		    -@
-		        Hide context names in list output. Use twice to show context
-		        names (default).
-		    -+
-		        Hide project names in list output. Use twice to show project
-		        names (default).
-		    -c
-		        Color mode
-		    -d CONFIG_FILE
-		        Use a configuration file other than the default ~/.todo/config
-		    -f
-		        Forces actions without confirmation or interactive input
-		    -h
-		        Display a short help message
-		    -p
-		        Plain mode turns off colors
-		    -P
-		        Hide priority labels in list output. Use twice to show
-		        priority labels (default).
-		    -a
-		        Don't auto-archive tasks automatically on completion
-		    -A
-		        Auto-archive tasks automatically on completion
-		    -n
-		        Don't preserve line numbers; automatically remove blank lines
-		        on task deletion
-		    -N
-		        Preserve line numbers
-		    -t
-		        Prepend the current date to a task automatically
-		        when it's added.
-		    -T
-		        Do not prepend the current date to a task automatically
-		        when it's added.
-		    -v
-		        Verbose mode turns on confirmation messages
-		    -vv
-		        Extra verbose mode prints some debugging information
-		    -V
-		        Displays version, license and credits
-		    -x
-		        Disables TODOTXT_FINAL_FILTER
 
+        addonHelp
+    exit 1
+}
 
-		  Environment variables:
+addonHelp()
-		    TODOTXT_AUTO_ARCHIVE            is same as option -a (0)/-A (1)
+{
-		    TODOTXT_CFG_FILE=CONFIG_FILE    is same as option -d CONFIG_FILE
+    if [ -d "$TODO_ACTIONS_DIR" ]; then
-		    TODOTXT_FORCE=1                 is same as option -f
+        didPrintAddonActionsHeader=
-		    TODOTXT_PRESERVE_LINE_NUMBERS   is same as option -n (0)/-N (1)
-		    TODOTXT_PLAIN                   is same as option -p (1)/-c (0)
-		    TODOTXT_DATE_ON_ADD             is same as option -t (1)/-T (0)
-		    TODOTXT_VERBOSE=1               is same as option -v
-		    TODOTXT_DEFAULT_ACTION=""       run this when called with no arguments
-		    TODOTXT_SORT_COMMAND="sort ..." customize list output
-		    TODOTXT_FINAL_FILTER="sed ..."  customize list after color, P@+ hiding
-	EndHelp
-
-    if [ -d "$TODO_ACTIONS_DIR" ]
-    then
-        echo ""
         for action in "$TODO_ACTIONS_DIR"/*
         do
-            if [ -f "$action" -a -x "$action" ]
+            if [ -f "$action" -a -x "$action" ]; then
-            then
+                if [ ! "$didPrintAddonActionsHeader" ]; then
+                    cat <<-EndAddonActionsHeader
+		  Add-on Actions:
+	EndAddonActionsHeader
+                    didPrintAddonActionsHeader=1
+                fi
                 "$action" usage
             fi
         done
-        echo ""
     fi
-
-
-    exit 1
 }
 
 die()
@@ -267,19 +296,63 @@ cleanup()
 
 cleaninput()
 {
-    # Cleanup the input
+    # Parameters:    When $1 = "for sed", performs additional escaping for use
-    # Replace newlines with spaces Always
+    #                in sed substitution with "|" separators.
-    input=`echo $input | tr -d '\r\n'`
+    # Precondition:  $input contains text to be cleaned.
+    # Postcondition: Modifies $input.
 
-    action_regexp="^\(append\|app\|prepend\|prep\|replace\)$"
+    # Replace CR and LF with space; tasks always comprise a single line.
+    input=${input//$'\r'/ }
+    input=${input//$'\n'/ }
 
-    # Check which action we are being used in as this affects what cleaning we do
+    if [ "$1" = "for sed" ]; then
-    if [ `echo $action | grep -c $action_regexp` -eq 1 ]; then
+        # This action uses sed with "|" as the substitution separator, and & as
-        # These actions use sed and & as the matched string so escape it
+        # the matched string; these must be escaped.
-        input=`echo $input | sed 's/\&/\\\&/g'`
+        # Backslashes must be escaped, too, and before the other stuff.
+        input=${input//\\/\\\\}
+        input=${input//|/\\|}
+        input=${input//&/\\&}
     fi
 }
 
+getPrefix()
+{
+    # Parameters:    $1: todo file; empty means $TODO_FILE.
+    # Returns:       Uppercase FILE prefix to be used in place of "TODO:" where
+    #                a different todo file can be specified.
+    local base=$(basename "${1:-$TODO_FILE}")
+    echo "${base%%.[^.]*}" | tr 'a-z' 'A-Z'
+}
+
+getTodo()
+{
+    # Parameters:    $1: task number
+    #                $2: Optional todo file
+    # Precondition:  $errmsg contains usage message.
+    # Postcondition: $todo contains task text.
+
+    local item=$1
+    [ -z "$item" ] && die "$errmsg"
+    [ "${item//[0-9]/}" ] && die "$errmsg"
+
+    todo=$(sed "$item!d" "${2:-$TODO_FILE}")
+    [ -z "$todo" ] && die "$(getPrefix "$2"): No task $item."
+}
+getNewtodo()
+{
+    # Parameters:    $1: task number
+    #                $2: Optional todo file
+    # Precondition:  None.
+    # Postcondition: $newtodo contains task text.
+
+    local item=$1
+    [ -z "$item" ] && die 'Programming error: $item should exist.'
+    [ "${item//[0-9]/}" ] && die 'Programming error: $item should be numeric.'
+
+    newtodo=$(sed "$item!d" "${2:-$TODO_FILE}")
+    [ -z "$newtodo" ] && die "$(getPrefix "$2"): No updated task $item."
+}
+
 archive()
 {
     #defragment blank lines
@@ -308,12 +381,7 @@ replaceOrPrepend()
       ;;
   esac
   shift; item=$1; shift
-
+  getTodo "$item"
-  [ -z "$item" ] && die "$errmsg"
-  [[ "$item" = +([0-9]) ]] || die "$errmsg"
-
-  todo=$(sed "$item!d" "$TODO_FILE")
-  [ -z "$todo" ] && die "TODO: No task $item."
 
   if [[ -z "$1" && $TODOTXT_FORCE = 0 ]]; then
     echo -n "$querytext"
@@ -321,11 +389,11 @@ replaceOrPrepend()
   else
     input=$*
   fi
-  cleaninput $input
+  cleaninput "for sed"
 
   # Retrieve existing priority and prepended date
-  priority=$(sed -e "$item!d" -e $item's/^\(([A-Z]) \)\{0,1\}\([0-9]\{2,4\}-[0-9]\{2\}-[0-9]\{2\} \)\{0,1\}.*/\1/' "$TODO_FILE")
+  priority=$(sed -e "$item!d" -e $item's/^\((.) \)\{0,1\}\([0-9]\{2,4\}-[0-9]\{2\}-[0-9]\{2\} \)\{0,1\}.*/\1/' "$TODO_FILE")
-  prepdate=$(sed -e "$item!d" -e $item's/^\(([A-Z]) \)\{0,1\}\([0-9]\{2,4\}-[0-9]\{2\}-[0-9]\{2\} \)\{0,1\}.*/\2/' "$TODO_FILE")
+  prepdate=$(sed -e "$item!d" -e $item's/^\((.) \)\{0,1\}\([0-9]\{2,4\}-[0-9]\{2\}-[0-9]\{2\} \)\{0,1\}.*/\2/' "$TODO_FILE")
 
   if [ "$prepdate" -a "$action" = "replace" ] && [ "$(echo "$input"|sed -e 's/^\([0-9]\{2,4\}-[0-9]\{2\}-[0-9]\{2\}\)\{0,1\}.*/\1/')" ]; then
     # If the replaced text starts with a date, it will replace the existing
@@ -338,7 +406,7 @@ replaceOrPrepend()
   # date again.
   sed -i.bak -e "$item s/^${priority}${prepdate}//" -e "$item s|^.*|${priority}${prepdate}${input}${backref}|" "$TODO_FILE"
   if [ $TODOTXT_VERBOSE -gt 0 ]; then
-    newtodo=$(sed "$item!d" "$TODO_FILE")
+    getNewtodo "$item"
     case "$action" in
       replace)
         echo "$item $todo"
@@ -416,7 +484,10 @@ do
         OVR_TODOTXT_FORCE=1
         ;;
     h )
-        shorthelp
+        # Short-circuit option parsing and forward to the action.
+        # Cannot just invoke shorthelp() because we need the configuration
+        # processed to locate the add-on actions directory.
+        set -- '-h' 'shorthelp'
         ;;
     n )
         OVR_TODOTXT_PRESERVE_LINE_NUMBERS=0
@@ -472,6 +543,7 @@ TODOTXT_AUTO_ARCHIVE=${TODOTXT_AUTO_ARCHIVE:-1}
 TODOTXT_DATE_ON_ADD=${TODOTXT_DATE_ON_ADD:-0}
 TODOTXT_DEFAULT_ACTION=${TODOTXT_DEFAULT_ACTION:-}
 TODOTXT_SORT_COMMAND=${TODOTXT_SORT_COMMAND:-env LC_COLLATE=C sort -f -k2}
+TODOTXT_DISABLE_FILTER=${TODOTXT_DISABLE_FILTER:-}
 TODOTXT_FINAL_FILTER=${TODOTXT_FINAL_FILTER:-cat}
 
 # Export all TODOTXT_* variables
@@ -531,7 +603,7 @@ export SENTENCE_DELIMITERS=',.:;'
 }
 
 [ -e "$TODOTXT_CFG_FILE" ] || {
-    CFG_FILE_ALT=`dirname "$0"`"/todo.cfg"
+    CFG_FILE_ALT=$(dirname "$0")"/todo.cfg"
 
     if [ -e "$CFG_FILE_ALT" ]
     then
@@ -615,22 +687,56 @@ fi
 _addto() {
     file="$1"
     input="$2"
-    cleaninput $input
+    cleaninput
 
     if [[ $TODOTXT_DATE_ON_ADD = 1 ]]; then
-        now=`date '+%Y-%m-%d'`
+        now=$(date '+%Y-%m-%d')
-        input="$now $input"
+        input=$(echo "$input" | sed -e 's/^\(([A-Z]) \)\{0,1\}/\1'"$now /")
     fi
     echo "$input" >> "$file"
     if [ $TODOTXT_VERBOSE -gt 0 ]; then
         TASKNUM=$(sed -n '$ =' "$file")
-        BASE=$(basename "$file")
-        PREFIX=$(echo ${BASE%%.[^.]*} | tr 'a-z' 'A-Z')
         echo "$TASKNUM $input"
-        echo "${PREFIX}: $TASKNUM added."
+        echo "$(getPrefix "$file"): $TASKNUM added."
     fi
 }
 
+shellquote()
+{
+    typeset -r qq=\'; printf %s\\n "'${1//\'/${qq}\\${qq}${qq}}'";
+}
+
+filtercommand()
+{
+    filter=${1:-}
+    shift
+    post_filter=${1:-}
+    shift
+
+    for search_term
+    do
+        ## See if the first character of $search_term is a dash
+        if [ "${search_term:0:1}" != '-' ]
+        then
+            ## First character isn't a dash: hide lines that don't match
+            ## this $search_term
+            filter="${filter:-}${filter:+ | }grep -i $(shellquote "$search_term")"
+        else
+            ## First character is a dash: hide lines that match this
+            ## $search_term
+            #
+            ## Remove the first character (-) before adding to our filter command
+            filter="${filter:-}${filter:+ | }grep -v -i $(shellquote "${search_term:1}")"
+        fi
+    done
+
+    [ -n "$post_filter" ] && {
+        filter="${filter:-}${filter:+ | }${post_filter:-}"
+    }
+
+    printf %s "$filter"
+}
+
 _list() {
     local FILE="$1"
     ## If the file starts with a "/" use absolute path. Otherwise,
@@ -654,32 +760,8 @@ _list() {
     ## Get our search arguments, if any
     shift ## was file name, new $1 is first search term
 
-    ## Prefix the filter_command with the pre_filter_command
+    ## Build the filter.
-    filter_command="${pre_filter_command:-}"
+    filter_command=$(filtercommand "${pre_filter_command:-}" "${post_filter_command:-}" "$@")
-
-    for search_term
-    do
-        ## See if the first character of $search_term is a dash
-        if [ "${search_term:0:1}" != '-' ]
-        then
-            ## First character isn't a dash: hide lines that don't match
-            ## this $search_term
-            filter_command="${filter_command:-} ${filter_command:+|} \
-                grep -i \"$search_term\" "
-        else
-            ## First character is a dash: hide lines that match this
-            ## $search_term
-            #
-            ## Remove the first character (-) before adding to our filter command
-            filter_command="${filter_command:-} ${filter_command:+|} \
-                grep -v -i \"${search_term:1}\" "
-        fi
-    done
-
-    ## If post_filter_command is set, append it to the filter_command
-    [ -n "$post_filter_command" ] && {
-        filter_command="${filter_command:-}${filter_command:+ | }${post_filter_command:-}"
-    }
 
     ## Figure out how much padding we need to use
     ## We need one level of padding for each power of 10 $LINES uses
@@ -697,7 +779,7 @@ _list() {
         | grep -v "^[ 0-9]\+ *$"
     )
     if [ "${filter_command}" ]; then
-        filtered_items=$(echo -n "$items" | eval ${filter_command})
+        filtered_items=$(echo -n "$items" | eval "${filter_command}")
     else
         filtered_items=$items
     fi
@@ -718,39 +800,39 @@ _list() {
                 return color
             }
             {
-                pos = match($0, /\([A-Z]\)/)
                 if (match($0, /^[0-9]+ x /)) {
                     print highlight("COLOR_DONE") $0 highlight("DEFAULT")
-                } else if (pos > 0) {
+                } else if (match($0, /^[0-9]+ \([A-Z]\)[[:space:]]/)) {
-                    clr = highlight("PRI_" substr($0, pos+1, 1))
+                    clr = highlight("PRI_" substr($0, RSTART + RLENGTH - 3, 1))
-                    print ( clr ? clr : highlight("PRI_X") ) $0 highlight("DEFAULT")
+                    print \
+                        (clr ? clr : highlight("PRI_X")) \
+                        (ENVIRON["HIDE_PRIORITY_SUBSTITUTION"] == "" ? $0 : substr($0, 1, RLENGTH - 4) substr($0, RSTART + RLENGTH)) \
+                        highlight("DEFAULT")
                 } else { print }
             }
           '''  \
         | sed '''
-            s/'${HIDE_PRIORITY_SUBSTITUTION:-^}'//g
+            s/'"${HIDE_PROJECTS_SUBSTITUTION:-^}"'//g
-            s/'${HIDE_PROJECTS_SUBSTITUTION:-^}'//g
+            s/'"${HIDE_CONTEXTS_SUBSTITUTION:-^}"'//g
-            s/'${HIDE_CONTEXTS_SUBSTITUTION:-^}'//g
+            s/'"${HIDE_CUSTOM_SUBSTITUTION:-^}"'//g
           '''                                                   \
         | eval ${TODOTXT_FINAL_FILTER}                          \
     )
     [ "$filtered_items" ] && echo "$filtered_items"
 
     if [ $TODOTXT_VERBOSE -gt 0 ]; then
-        BASE=$(basename "$FILE")
-        PREFIX=$(echo ${BASE%%.[^.]*} | tr 'a-z' 'A-Z')
         NUMTASKS=$( echo -n "$filtered_items" | sed -n '$ =' )
         TOTALTASKS=$( echo -n "$items" | sed -n '$ =' )
 
         echo "--"
-        echo "${PREFIX}: ${NUMTASKS:-0} of ${TOTALTASKS:-0} tasks shown"
+        echo "$(getPrefix "$FILE"): ${NUMTASKS:-0} of ${TOTALTASKS:-0} tasks shown"
     fi
     if [ $TODOTXT_VERBOSE -gt 1 ]; then
         echo "TODO DEBUG: Filter Command was: ${filter_command:-cat}"
     fi
 }
 
-export -f _list die
+export -f cleaninput getPrefix getTodo getNewtodo shellquote filtercommand _list die
 
 # == HANDLE ACTION ==
 action=$( printf "%s\n" "$ACTION" | tr 'A-Z' 'a-z' )
@@ -827,11 +909,8 @@ case $action in
 "append" | "app" )
     errmsg="usage: $TODO_SH append ITEM# \"TEXT TO APPEND\""
     shift; item=$1; shift
+    getTodo "$item"
 
-    [ -z "$item" ] && die "$errmsg"
-    [[ "$item" = +([0-9]) ]] || die "$errmsg"
-    todo=$(sed "$item!d" "$TODO_FILE")
-    [ -z "$todo" ] && die "TODO: No task $item."
     if [[ -z "$1" && $TODOTXT_FORCE = 0 ]]; then
         echo -n "Append: "
         read input
@@ -842,11 +921,11 @@ case $action in
       [$SENTENCE_DELIMITERS]*)  appendspace=;;
       *)                        appendspace=" ";;
     esac
-    cleaninput $input
+    cleaninput "for sed"
 
     if sed -i.bak $item" s|^.*|&${appendspace}${input}|" "$TODO_FILE"; then
         if [ $TODOTXT_VERBOSE -gt 0 ]; then
-            newtodo=$(sed "$item!d" "$TODO_FILE")
+            getNewtodo "$item"
             echo "$item $newtodo"
 	fi
     else
@@ -861,14 +940,11 @@ case $action in
     # replace deleted line with a blank line when TODOTXT_PRESERVE_LINE_NUMBERS is 1
     errmsg="usage: $TODO_SH del ITEM# [TERM]"
     item=$2
-    [ -z "$item" ] && die "$errmsg"
+    getTodo "$item"
-    [[ "$item" = +([0-9]) ]] || die "$errmsg"
-    DELETEME=$(sed "$item!d" "$TODO_FILE")
-    [ -z "$DELETEME" ] && die "TODO: No task $item."
 
     if [ -z "$3" ]; then
         if  [ $TODOTXT_FORCE = 0 ]; then
-            echo "Delete '$DELETEME'?  (y/n)"
+            echo "Delete '$todo'?  (y/n)"
             read ANSWER
         else
             ANSWER="y"
@@ -882,7 +958,7 @@ case $action in
                 sed -i.bak -e $item"s/^.*//" "$TODO_FILE"
             fi
             if [ $TODOTXT_VERBOSE -gt 0 ]; then
-                echo "$item $DELETEME"
+                echo "$item $todo"
                 echo "TODO: $item deleted."
             fi
         else
@@ -896,13 +972,13 @@ case $action in
             -e $item"s/ *$3  */ /g" \
             -e $item"s/$3//g" \
             "$TODO_FILE"
-        newtodo=$(sed "$item!d" "$TODO_FILE")
+        getNewtodo "$item"
-        if [ "$DELETEME" = "$newtodo" ]; then
+        if [ "$todo" = "$newtodo" ]; then
-            [ $TODOTXT_VERBOSE -gt 0 ] && echo "$item $DELETEME"
+            [ $TODOTXT_VERBOSE -gt 0 ] && echo "$item $todo"
             die "TODO: '$3' not found; no removal done."
         fi
         if [ $TODOTXT_VERBOSE -gt 0 ]; then
-            echo "$item $DELETEME"
+            echo "$item $todo"
             echo "TODO: Removed '$3' from task."
             echo "$item $newtodo"
         fi
@@ -916,16 +992,14 @@ case $action in
 
     # Split multiple depri's, if comma separated change to whitespace separated
     # Loop the 'depri' function for each item
-    for item in `echo $* | tr ',' ' '`; do
+    for item in $(echo $* | tr ',' ' '); do
-	[[ "$item" = +([0-9]) ]] || die "$errmsg"
+        getTodo "$item"
-	todo=$(sed "$item!d" "$TODO_FILE")
-	[ -z "$todo" ] && die "TODO: No task $item."
 
-	if sed "$item!d" "$TODO_FILE" | grep "^(.) " > /dev/null; then
+	if [[ "$todo" = \(?\)\ * ]]; then
 	    sed -i.bak -e $item"s/^(.) //" "$TODO_FILE"
 	    if [ $TODOTXT_VERBOSE -gt 0 ]; then
-		NEWTODO=$(sed "$item!d" "$TODO_FILE")
+		getNewtodo "$item"
-		echo "$item $NEWTODO"
+		echo "$item $newtodo"
 		echo "TODO: $item deprioritized."
 	    fi
 	else
@@ -942,26 +1016,22 @@ case $action in
 
     # Split multiple do's, if comma separated change to whitespace separated
     # Loop the 'do' function for each item
-    for item in `echo $* | tr ',' ' '`; do 
+    for item in $(echo $* | tr ',' ' '); do
-        [ -z "$item" ] && die "$errmsg"
+        getTodo "$item"
-        [[ "$item" = +([0-9]) ]] || die "$errmsg"
-
-        todo=$(sed "$item!d" "$TODO_FILE")
-        [ -z "$todo" ] && die "TODO: No task $item."
 
         # Check if this item has already been done
-        if [ `echo $todo | grep -c "^x "` -eq 0 ] ; then
+        if [ "${todo:0:2}" != "x " ]; then
-            now=`date '+%Y-%m-%d'`
+            now=$(date '+%Y-%m-%d')
             # remove priority once item is done
             sed -i.bak $item"s/^(.) //" "$TODO_FILE"
             sed -i.bak $item"s|^|x $now |" "$TODO_FILE"
             if [ $TODOTXT_VERBOSE -gt 0 ]; then
-                newtodo=$(sed "$item!d" "$TODO_FILE")
+                getNewtodo "$item"
                 echo "$item $newtodo"
                 echo "TODO: $item marked as done."
 	    fi
         else
-            echo "$item is already marked done"
+            echo "TODO: $item is already marked done."
         fi
     done
 
@@ -980,6 +1050,16 @@ case $action in
     help # just in case something failed above, we go ahead and just spew to STDOUT
     ;;
 
+"shorthelp" )
+    if [ -t 1 ] ; then # STDOUT is a TTY
+        if which "${PAGER:-less}" >/dev/null 2>&1; then
+            # we have a working PAGER (or less as a default)
+            shorthelp | "${PAGER:-less}" && exit 0
+        fi
+    fi
+    shorthelp # just in case something failed above, we go ahead and just spew to STDOUT
+    ;;
+
 "list" | "ls" )
     shift  ## Was ls; new $1 is first search term
     _list "$TODO_FILE" "$@"
@@ -994,10 +1074,15 @@ case $action in
 
 "listfile" | "lf" )
     shift  ## Was listfile, next $1 is file name
-    FILE="$1"
+    if [ $# -eq 0 ]; then
-    shift  ## Was filename; next $1 is first search term
+        [ $TODOTXT_VERBOSE -gt 0 ] && echo "Files in the todo.txt directory:"
+        cd "$TODO_DIR" && ls -1 *.txt
+    else
+        FILE="$1"
+        shift  ## Was filename; next $1 is first search term
 
-    _list "$FILE" "$@"
+        _list "$FILE" "$@"
+    fi
     ;;
 
 "listcon" | "lsc" )
@@ -1005,26 +1090,16 @@ case $action in
     ;;
 
 "listproj" | "lsprj" )
-    grep -o '[^ ]*+[^ ]\+' "$TODO_FILE" | grep '^+' | sort -u
+    shift
+    eval "$(filtercommand 'cat "$TODO_FILE"' '' "$@")" | grep -o '[^ ]*+[^ ]\+' | grep '^+' | sort -u
     ;;
 
 "listpri" | "lsp" )
-    shift ## was "listpri", new $1 is priority to list
+    shift ## was "listpri", new $1 is priority to list or first TERM
 
-    if [ "${1:-}" ]
+    pri=$(printf "%s\n" "$1" | tr 'a-z' 'A-Z' | grep '^[A-Z]$') && shift || pri="[A-Z]"
-    then
+    post_filter_command="grep '^ *[0-9]\+ (${pri}) '"
-        ## A priority was specified
+    _list "$TODO_FILE" "$@"
-        pri=$( printf "%s\n" "$1" | tr 'a-z' 'A-Z' | grep '^[A-Z]$' ) || {
-            die "usage: $TODO_SH listpri PRIORITY
-            note: PRIORITY must a single letter from A to Z."
-        }
-    else
-        ## No priority specified; show all priority tasks
-        pri="[[:upper:]]"
-    fi
-    pri="($pri)"
-
-    _list "$TODO_FILE" "$pri"
     ;;
 
 "move" | "mv" )
@@ -1034,19 +1109,16 @@ case $action in
     dest="$TODO_DIR/$3"
     src="$TODO_DIR/$4"
 
-    [ -z "$item" ] && die "$errmsg"
     [ -z "$4" ] && src="$TODO_FILE"
     [ -z "$dest" ] && die "$errmsg"
 
-    [[ "$item" = +([0-9]) ]] || die "$errmsg"
-
     [ -f "$src" ] || die "TODO: Source file $src does not exist."
     [ -f "$dest" ] || die "TODO: Destination file $dest does not exist."
 
-    MOVEME=$(sed "$item!d" "$src")
+    getTodo "$item" "$src"
-    [ -z "$MOVEME" ] && die "$item: No such item in $src."
+    [ -z "$todo" ] && die "$item: No such item in $src."
     if  [ $TODOTXT_FORCE = 0 ]; then
-        echo "Move '$MOVEME' from $src to $dest? (y/n)"
+        echo "Move '$todo' from $src to $dest? (y/n)"
         read ANSWER
     else
         ANSWER="y"
@@ -1059,10 +1131,10 @@ case $action in
             # leave blank line behind (preserves line numbers)
             sed -i.bak -e $item"s/^.*//" "$src"
         fi
-        echo "$MOVEME" >> "$dest"
+        echo "$todo" >> "$dest"
 
         if [ $TODOTXT_VERBOSE -gt 0 ]; then
-            echo "$item $MOVEME"
+            echo "$item $todo"
             echo "TODO: $item moved from '$src' to '$dest'."
         fi
     else
@@ -1083,21 +1155,30 @@ case $action in
 note: PRIORITY must be anywhere from A to Z."
 
     [ "$#" -ne 3 ] && die "$errmsg"
-    [[ "$item" = +([0-9]) ]] || die "$errmsg"
     [[ "$newpri" = @([A-Z]) ]] || die "$errmsg"
+    getTodo "$item"
 
-    sed -e $item"s/^(.) //" -e $item"s/^/($newpri) /" "$TODO_FILE" > /dev/null 2>&1
+    oldpri=
+    if [[ "$todo" = \(?\)\ * ]]; then
+        oldpri=${todo:1:1}
+    fi
 
-    if [ "$?" -eq 0 ]; then
+    if [ "$oldpri" != "$newpri" ]; then
-        #it's all good, continue
         sed -i.bak -e $item"s/^(.) //" -e $item"s/^/($newpri) /" "$TODO_FILE"
-        if [ $TODOTXT_VERBOSE -gt 0 ]; then
+    fi
-            NEWTODO=$(sed "$item!d" "$TODO_FILE")
+    if [ $TODOTXT_VERBOSE -gt 0 ]; then
-            echo "$item $NEWTODO"
+        getNewtodo "$item"
-            echo "TODO: $item prioritized ($newpri)."
+        echo "$item $newtodo"
-	fi
+        if [ "$oldpri" != "$newpri" ]; then
-    else
+            if [ "$oldpri" ]; then
-        die "$errmsg"
+                echo "TODO: $item re-prioritized from ($oldpri) to ($newpri)."
+            else
+                echo "TODO: $item prioritized ($newpri)."
+            fi
+        fi
+    fi
+    if [ "$oldpri" = "$newpri" ]; then
+        echo "TODO: $item already prioritized ($newpri)."
     fi
     ;;
 

todo_completion

@@ -0,0 +1,71 @@
+#!/bin/bash source-this-script
+[ "$BASH_VERSION" ] || return
+
+_todo()
+{
+    local cur prev opts
+    COMPREPLY=()
+    cur="${COMP_WORDS[COMP_CWORD]}"
+    prev="${COMP_WORDS[COMP_CWORD-1]}"
+
+    local -r OPTS="-@ -@@ -+ -++ -d -f -h -p -P -PP -a -n -t -v -vv -V -x"
+    local -r COMMANDS="\
+        add a addto addm append app archive command del  \
+        rm depri dp do help list ls listall lsa listcon  \
+        lsc listfile lf listpri lsp listproj lsprj move \
+        mv prepend prep pri p replace report shorthelp"
+
+    # Add custom commands from add-ons, if installed.
+    # TODO: Filter for executable flag of files found in $TODO_ACTIONS_DIR.
+    local allCommands="$COMMANDS $('ls' "${TODO_ACTIONS_DIR:-$HOME/.todo.actions.d}/" 2>/dev/null)"
+
+    local completions
+    if [ $COMP_CWORD -eq 1 ]; then
+        completions="$allCommands $OPTS"
+    elif [[ $COMP_CWORD -gt 2 && ( \
+        "${COMP_WORDS[COMP_CWORD-2]}" =~ ^(move|mv)$ || \
+        "${COMP_WORDS[COMP_CWORD-3]}" =~ ^(move|mv)$ ) ]]; then
+        # "move ITEM# DEST [SRC]" has file arguments on positions 2 and 3.
+        completions=$(TODOTXT_VERBOSE=0 todo.sh command listfile)
+    else
+        case "$prev" in
+            command)
+                completions=$COMMANDS;;
+            addto|listfile|lf)
+                completions=$(TODOTXT_VERBOSE=0 todo.sh command listfile);;
+            -*) completions="$allCommands $OPTS";;
+            *)  case "$cur" in
+                    +*) completions=$(TODOTXT_VERBOSE=0 todo.sh command listproj);;
+                    @*) completions=$(TODOTXT_VERBOSE=0 todo.sh command listcon);;
+                    *)  if [[ "$cur" =~ ^[0-9]+$ ]]; then
+                            local item=$(TODOTXT_VERBOSE=0 todo.sh -@ -+ -p -x command ls "^ *${cur} " | head -n 1)
+
+                            # Remove the (padded) task number; we prepend the
+                            # user-provided $cur.
+                            item=${item#* }
+
+                            # Remove the timestamp prepended by the -t option;
+                            # there's no todo.txt option for that yet.
+                            item=${item#[0-9][0-9][0-9][0-9]-[0-9][0-9]-[0-9][0-9] }
+
+                            # Append task text as a shell comment. This
+                            # completion can be a safety check before a
+                            # destructive todo.txt operation.
+                            [ "$item" ] && COMPREPLY[0]="$cur # $item"
+                            return 0
+                        else
+                            return 0
+                        fi
+                        ;;
+                esac
+                ;;
+        esac
+    fi
+
+    COMPREPLY=( $( compgen -W "$completions" -- $cur ))
+    return 0
+}
+complete -F _todo todo.sh
+# If you define an alias (e.g. "t") to todo.sh, you need to explicitly enable
+# completion for it, too:
+#complete -F _todo t