Re: HIST_IGNORE_DUPS also ignores command lines that differ by a space between quotes

[Bart Schaefer <schaefer@brasslantern.com>]

On Tue, Mar 19, 2024 at 5:34 AM Vincent Lefevre <vincent@vinc17.net> wrote:
>
> On 2024-03-19 12:08:26 +0100, Mikael Magnusson wrote:
> > and in hashtable.c (weird place for it):
> > /* Compare two strings with normalized white-space */
>
> It is placed in hashtable.c perhaps because of its use for cmpnodes

Yes.  That's connected to what I said about history search also
working the way ignoredups does.

That placement is not necessary given that it isn't a static function
... if it ever was, that's buried somewhere in the pre-version-control
zsh-workers archives.

> > seems you could simply replace histstrcmp with strcmp and be happy.
>
> Thanks. This now works as expected.
>
> BTW, without this change, the following commands are regarded as
> the same for HIST_IGNORE_DUPS, while they are very different:

Although this statement is correct, I'm reluctant to discard a quarter
century of practice about which there has not previously been a
complaint.  It could lead to significantly larger history files and/or
the "expiration" of commands with more obvious distinctions -- not
because those distinctions are more "important" but because they're
more likely to be noticed and their loss complained about.

So how about this as a compromise:

diff --git a/Src/hashtable.c b/Src/hashtable.c
index 75b06c4ad..e1f575a52 100644
--- a/Src/hashtable.c
+++ b/Src/hashtable.c
@@ -1397,6 +1397,14 @@ histstrcmp(const char *str1, const char *str2)
 {
     while (inblank(*str1)) str1++;
     while (inblank(*str2)) str2++;
+
+    /* If significant whitespace has already been eliminated,
+     * there is no reason to expend similar effort here.  Also,
+     * this is more accurate in cases of quoted whitespace.
+     */
+    if (isset(HISTREDUCEBLANKS))
+       return strcmp(str1, str2);
+
     while (*str1 && *str2) {
        if (inblank(*str1)) {
            if (!inblank(*str2))