feat: add fuzzy search

Author: qoomon

README.md

@@ -117,6 +117,11 @@ default values only after having loaded this script into your ZSH session.
   Flags" section in the zshexpn(1) man page to learn about the kinds of
   values you may assign to this variable.
 
+* `HISTORY_SUBSTRING_SEARCH_FUZZY` is a global variable that defines
+  how the command history will be searched for your query. If set to a non-empty
+  value, causes this script to perform a fuzzy search by words, matching in
+  given order e.g. `ab c` will match `*ab*c*`
+
 * `HISTORY_SUBSTRING_SEARCH_ENSURE_UNIQUE` is a global variable that defines
   whether all search results returned are _unique_. If set to a non-empty
   value, then only unique search results are presented. This behaviour is off

zsh-history-substring-search.zsh

@@ -7,6 +7,7 @@
 # Copyright (c) 2011 Sorin Ionescu
 # Copyright (c) 2011 Vincent Guerci
 # Copyright (c) 2016 Geza Lore
+# Copyright (c) 2017 Bengt Brodersen
 # All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
@@ -51,6 +52,7 @@ typeset -g _history_substring_search_refresh_display
 typeset -g _history_substring_search_query_highlight
 typeset -g _history_substring_search_result
 typeset -g _history_substring_search_query
+typeset -g -a _history_substring_search_query_parts
 typeset -g -A _history_substring_search_raw_matches
 typeset -g -i _history_substring_search_raw_match_index
 typeset -g -A _history_substring_search_matches
@@ -65,6 +67,7 @@ typeset -g HISTORY_SUBSTRING_SEARCH_HIGHLIGHT_FOUND='bg=magenta,fg=white,bold'
 typeset -g HISTORY_SUBSTRING_SEARCH_HIGHLIGHT_NOT_FOUND='bg=red,fg=white,bold'
 typeset -g HISTORY_SUBSTRING_SEARCH_GLOBBING_FLAGS='i'
 typeset -g HISTORY_SUBSTRING_SEARCH_ENSURE_UNIQUE=''
+typeset -g HISTORY_SUBSTRING_SEARCH_FUZZY=''
 typeset -g _history_substring_search_{refresh_display,query_highlight,result,query,match_index,raw_match_index}
 typeset -ga _history_substring_search{,_raw}_matches
 
@@ -223,6 +226,7 @@ _history-substring-search-begin() {
     # speed things up a little.
     #
     _history_substring_search_query=
+    _history_substring_search_query_parts=()
     _history_substring_search_raw_matches=()
 
   else
@@ -233,20 +237,31 @@ _history-substring-search-begin() {
     _history_substring_search_query=$BUFFER
 
     #
-    # $BUFFER contains the text that is in the command-line currently.
-    # we put an extra "\\" before meta characters such as "\(" and "\)",
-    # so that they become "\\\(" and "\\\)".
+    # compose search pattern
     #
-    local escaped_query=${BUFFER//(#m)[\][()|\\*?#<>~^]/\\$MATCH}
+    if [[ -n $HISTORY_SUBSTRING_SEARCH_FUZZY ]]; then
+      #
+      # `=` split string in arguments
+      #
+      _history_substring_search_query_parts=(${=_history_substring_search_query})
+    else
+      _history_substring_search_query_parts=(${_history_substring_search_query})
+    fi
 
     #
-    # Find all occurrences of the search query in the history file.
+    # Escape and join query parts with wildcard character '*' as seperator
+    # `(j:CHAR:)` join array to string with CHAR as seperator
+    #
+    local search_pattern="*${(j:*:)_history_substring_search_query_parts[@]//(#m)[\][()|\\*?#<>~^]/\\$MATCH}*"
+
+    #
+    # Find all occurrences of the search pattern in the history file.
     #
     # (k) returns the "keys" (history index numbers) instead of the values
     # (R) returns values in reverse older, so the index of the youngest
     # matching history entry is at the head of the list.
     #
-    _history_substring_search_raw_matches=(${(k)history[(R)(#$HISTORY_SUBSTRING_SEARCH_GLOBBING_FLAGS)*${escaped_query}*]})
+    _history_substring_search_raw_matches=(${(k)history[(R)(#$HISTORY_SUBSTRING_SEARCH_GLOBBING_FLAGS)${search_pattern}]})
   fi
 
   #
@@ -309,16 +324,20 @@ _history-substring-search-end() {
   _zsh_highlight
 
   # highlight the search query inside the command line
-  if [[ -n $_history_substring_search_query_highlight && -n $_history_substring_search_query ]]; then
-    #
-    # The following expression yields a variable $MBEGIN, which
-    # indicates the begin position + 1 of the first occurrence
-    # of _history_substring_search_query in $BUFFER.
-    #
-    : ${(S)BUFFER##(#m$HISTORY_SUBSTRING_SEARCH_GLOBBING_FLAGS)($_history_substring_search_query##)}
-    local begin=$(( MBEGIN - 1 ))
-    local end=$(( begin + $#_history_substring_search_query ))
-    region_highlight+=("$begin $end $_history_substring_search_query_highlight")
+  if [[ -n $_history_substring_search_query_highlight ]]; then
+    # highlight first matching query parts
+    local highlight_start_index=0
+    local highlight_end_index=0
+    for query_part in $_history_substring_search_query_parts; do
+      local escaped_query_part=${query_part//(#m)[\][()|\\*?#<>~^]/\\$MATCH}
+      # (i) get index of pattern
+      local query_part_match_index=${${BUFFER:$highlight_start_index}[(i)(#$HISTORY_SUBSTRING_SEARCH_GLOBBING_FLAGS)${escaped_query_part}]}
+      if [[ $query_part_match_index -le ${#BUFFER:$highlight_start_index} ]]; then
+        highlight_start_index=$(( $highlight_start_index + $query_part_match_index ))
+        highlight_end_index=$(( $highlight_start_index + ${#query_part} ))
+        region_highlight+=("$(($highlight_start_index - 1)) $(($highlight_end_index - 1)) $_history_substring_search_query_highlight")
+      fi
+    done
   fi
 
   # For debugging purposes: