Honor HISTCONTROL ignorespace and ignoreboth

After 3458480

    Remove ignorespace from $HISTCONTROL

and after 7e55ac1

    Follow up commit for issue #6

    -Replace ignoreboth with simpley ignoredups

this script would remove 'ignorespace' and would replace 'ignoreboth'
with 'ignoredups'.  This effectively disables the functionality of not
adding space prefixed commands into history.  It used to happen
siliently and could be quite confusing to users who use this feature.

This script relies on the command to be in the history, but we can
mostly fix the issue by "manual" removing a whitespace prefixed command
from the history after reading it from there.

Author: ilya-bobyr

README.md

@@ -30,6 +30,8 @@ curl https://raw.githubusercontent.com/rcaloras/bash-preexec/master/bash-preexec
 echo '[[ -f ~/.bash-preexec.sh ]] && source ~/.bash-preexec.sh' >> ~/.bashrc
 ```
 
+NOTE: this script may change your `HISTCONTROL` value by removing `ignorespace` and/or replacing `ignoreboth` with `ignoredups`.  See [`HISTCONTROL` interaction](#histcontrol-interaction) for details.
+
 ## Usage
 Two functions **preexec** and **precmd** can now be defined and they'll be automatically invoked by bash-preexec if they exist.
 
@@ -91,6 +93,10 @@ export __bp_enable_subshells="true"
 ```
 This is disabled by default due to buggy situations related to to `functrace` and Bash's `DEBUG trap`. See [Issue #25](https://github.com/rcaloras/bash-preexec/issues/25)
 
+## `HISTCONTROL` interaction
+
+In order to be able to provide the last command text to the `preexec` hook, this script will remove `ignorespace` and/or will replace `ignoreboth` with `ignoredups` in your `HISTCONTROL` variable.  It will remember if `HISTCONTROL` has been modified and will remove the last command from the history "manually", after reading the last command from the history list.  This may cause issues when you have scripts that rely on the literal value of `HISTCONTROL` or manipulate history in their own ways.
+
 ## Tests
 You can run tests using [Bats](https://github.com/bats-core/bats-core).
 ```bash

bash-preexec.sh

@@ -51,6 +51,7 @@ __bp_imported="defined"
 __bp_last_ret_value="$?"
 BP_PIPESTATUS=("${PIPESTATUS[@]}")
 __bp_last_argument_prev_command="$_"
+__bp_ignorespace=
 
 __bp_inside_precmd=0
 __bp_inside_preexec=0
@@ -70,17 +71,22 @@ __bp_require_not_readonly() {
   done
 }
 
-# Remove ignorespace and or replace ignoreboth from HISTCONTROL
-# so we can accurately invoke preexec with a command from our
-# history even if it starts with a space.
+# Remove "ignorespace" and/or replace "ignoreboth" in HISTCONTROL so we can
+# accurately invoke preexec with a command from our history even if it starts
+# with a space.  We then remove commands that start with a space from the
+# history "manually", if either "ignorespace" or "ignoreboth" was part of
+# HISTCONTROL.
 __bp_adjust_histcontrol() {
     local histcontrol
-    histcontrol="${HISTCONTROL//ignorespace}"
-    # Replace ignoreboth with ignoredups
-    if [[ "$histcontrol" == *"ignoreboth"* ]]; then
-        histcontrol="ignoredups:${histcontrol//ignoreboth}"
-    fi;
-    export HISTCONTROL="$histcontrol"
+    if [[ ":$HISTCONTROL:" == *":ignorespace:"* || ":$HISTCONTROL:" == *":ignoreboth:"* ]]; then
+      __bp_ignorespace=yes
+    fi
+    histcontrol=:${HISTCONTROL//:/::}:
+    histcontrol=${histcontrol//:ignorespace:}
+    histcontrol=${histcontrol//:ignoreboth:/:ignoredups:}
+    histcontrol=${histcontrol//::/:}
+    histcontrol=${histcontrol#:}
+    export HISTCONTROL=${histcontrol%:}
 }
 
 # This variable describes whether we are currently in "interactive mode";
@@ -239,6 +245,23 @@ __bp_preexec_invoke_exec() {
         return
     fi
 
+    # If we have removed "ignorespace" or "ignoreboth" from HISTCONTROL
+    # during setup, we need to remove commands that start with a space from
+    # the history ourselves.
+
+    # With bash 5.0 or above, we could have just ran
+    #
+    #   builtin history -d -1
+    #
+    # Negative indices for `-d` are not supported before 5.0, so we compute the
+    # length of the history list explicit, to delete the last entry.
+    if [[ -n "$__bp_ignorespace" && "$this_command" == " "* ]]; then
+        builtin history -d "$(
+            export LC_ALL=C
+            HISTTIMEFORMAT= history 1 | sed '1 s/^ *\([0-9][0-9]*\).*/\1/'
+        )"
+    fi
+
     # Invoke every function defined in our function array.
     local preexec_function
     local preexec_function_ret_value

test/bash-preexec.bats

@@ -306,18 +306,17 @@ test_preexec_echo() {
     # Should remove ignorespace
     HISTCONTROL="ignorespace:ignoredups:*"
     __bp_adjust_histcontrol
-    [ "$HISTCONTROL" == ":ignoredups:*" ]
+    [ "$HISTCONTROL" == "ignoredups:*" ]
 
     # Should remove ignoreboth and replace it with ignoredups
     HISTCONTROL="ignoreboth"
     __bp_adjust_histcontrol
-    [ "$HISTCONTROL" == "ignoredups:" ]
+    [ "$HISTCONTROL" == "ignoredups" ]
 
     # Handle a few inputs
     HISTCONTROL="ignoreboth:ignorespace:some_thing_else"
     __bp_adjust_histcontrol
-    echo "$HISTCONTROL"
-    [ "$HISTCONTROL" == "ignoredups:::some_thing_else" ]
+    [ "$HISTCONTROL" == "ignoredups:some_thing_else" ]
 
 }
 
@@ -340,6 +339,7 @@ test_preexec_echo() {
 
     run '__bp_preexec_invoke_exec'
     [ $status -eq 0 ]
+    echo "__bp_preexec_invoke_exec: output: '$output'"
     [ "$output" == " this command has whitespace " ]
 }
 
@@ -362,3 +362,33 @@ a multiline string'" ]
     [ $status -eq 0 ]
     [ "$output" == '-n' ]
 }
+
+@test "HISTCONTROL is updated, but ignorespace functionality is honoured" {
+    preexec_functions+=(test_preexec_echo)
+    HISTCONTROL=ignorespace:ignoreboth
+
+    __bp_adjust_histcontrol
+
+    [[ "$HISTCONTROL" == "ignoredups" ]]
+
+    __bp_interactive_mode
+
+    command1="this command is in the history"
+
+    history -s "$command1"
+    run '__bp_preexec_invoke_exec'
+    [[ $status == 0 ]]
+    [[ "$output" == "$command1" ]]
+    last_history=$(HISTTIMEFORMAT= history 1 | sed '1 s/^ *[0-9][0-9]* *//')
+    [[ "$last_history" == "$command1" ]]
+
+    command2=" this should not be in the history"
+
+    history -s "$command2"
+    # we need to extract command history in the subshell, as the parent shell
+    # history is actually not affected.
+    output=$(__bp_preexec_invoke_exec && \
+        printf "last_history: %s\n" "$(HISTTIMEFORMAT= history 1 | sed '1 s/^ *[0-9][0-9]* *//')" )
+    [[ $status == 0 ]]
+    [[ "$output" == "$command2"$'\n'"last_history: $command1" ]]
+}