eliminate compile warnings and augment changelog

Update the CHANGELOG to more accurately reflect what will be included in
the 2.4.0 release vis-a-vis the `history` command behavior.

I noticed that the compiler was emitting some harmless warnings related
to the history changes so deal with those as well.

CHANGELOG.md

@@ -2,7 +2,9 @@
 
 ## Significant changes
 - The clipboard integration has been revamped with explicit bindings. The killring commands no longer copy from, or paste to, the X11 clipboard - use the new copy (`C-x`) and paste (`C-v`) bindings instead. The clipboard is now available on OS X as well as systems using X11 (e.g. Linux). (#3061)
-- `history` uses subcommands (`history delete`) rather than options (`history --delete`) for its actions (#3367). New options have been added, including `--max=n` to limit the number of history entries and `--show-time` option to show timestamps (#3175, #3244).
+- `history` uses subcommands (`history delete`) rather than options (`history --delete`) for its actions (#3367). You can no longer specify multiple actions via flags (e.g., `history --delete --save something`).
+- New `history` options have been added, including `--max=n` to limit the number of history entries and `--show-time` option to show timestamps (#3175, #3244).
+- `history search` is now case-insensitive by default (which also affects `history delete`). 
 - Vi-style bindings no longer include all of the default emacs-style bindings; instead, they share some definitions (#3068).
 - If there is no locale set in the environment, various known system configuration files will be checked for a default, otherwise forcing en_US-UTF.8 (#277).
 - A number followed by a caret (e.g. `5^`) is no longer treated as a redirection (#1873).

src/history.cpp

@@ -1,4 +1,5 @@
 // History functions, part of the user interface.
+//
 #include "config.h"  // IWYU pragma: keep
 
 #include <assert.h>

src/history.h

@@ -265,7 +265,10 @@ class history_search_t {
     // The history in which we are searching.
     history_t *history;
 
-    // Our type.
+    // The search term.
+    wcstring term;
+
+    // Our search type.
     enum history_search_type_t search_type;
     bool case_sensitive;
 
@@ -276,9 +279,6 @@ class history_search_t {
     // Returns yes if a given term is in prev_matches.
     bool match_already_made(const wcstring &match) const;
 
-    // The search term.
-    wcstring term;
-
     // Additional strings to skip (sorted).
     wcstring_list_t external_skips;
 
@@ -326,7 +326,7 @@ class history_search_t {
     }
 
     // Default constructor.
-    history_search_t() : history(), term() {}
+    history_search_t() : history(), term(), search_type(HISTORY_SEARCH_TYPE_CONTAINS), case_sensitive(true) {}
 };
 
 // Init history library. The history file won't actually be loaded until the first time a history