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.

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
 #

todo.sh

@@ -199,10 +199,7 @@ help()
 		    list [TERM...]
 		    ls [TERM...]
 		      Displays all tasks that contain TERM(s) sorted by priority with line
-		      numbers.  Each task must match all TERMs (logical AND); to display
+		      numbers.  If no TERM specified, lists entire todo.txt.
-		      tasks that contain any TERM (logical OR), use
-		      "TERM1\|TERM2\|..." (with quotes), or TERM1\\\|TERM2 (unquoted).
-		      If no TERM specified, lists entire todo.txt.
 
 		    listall [TERM...]
 		    lsa [TERM...]
@@ -218,7 +215,7 @@ help()
 		    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(s) in SRC file.
+		      all lines that contain TERM in SRC file.
 		      Without any arguments, the names of all text files in the todo.txt
 		      directory are listed.
 
@@ -226,7 +223,7 @@ help()
 		    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(s).
+		      If TERM specified, lists only prioritized tasks that contain TERM.
 
 		    listproj
 		    lsprj
@@ -815,8 +812,9 @@ _list() {
             }
           '''  \
         | sed '''
-            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}                          \
     )