Implement tab completion under libedit

I haven't tested it with real wide characters but it will have to do.
I wasn't even sure if this piece of crap could be coerced into doing
this at first, so it's a win for me.

It uses a variation of the code in degesch where we /don't/ want to
print the list of candidates on partial failure.

Updates #1
This commit is contained in:
Přemysl Eric Janouch 2020-10-13 03:03:52 +02:00
parent 5d2cd01db0
commit 2b18ebf314
Signed by: p
GPG Key ID: A0420B94F92B9493
1 changed files with 137 additions and 23 deletions

View File

@ -141,6 +141,8 @@ struct input
void (*on_input) (char *line, void *user_data);
/// User requested external line editing
void (*on_run_editor) (const char *line, void *user_data);
/// Tab completion generator, returns locale encoding strings or NULL
char *(*complete_start_word) (const char *text, int state);
};
struct input_vtable
@ -268,7 +270,19 @@ input_rl_on_startup (void)
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
static char **app_readline_completion (const char *text, int start, int end);
static char **
app_readline_completion (const char *text, int start, int end)
{
(void) end;
// Only customize matches for the first token, which is the method name
if (start)
return NULL;
// Don't iterate over filenames and stuff in this case
rl_attempted_completion_over = true;
return rl_completion_matches (text, g_input_rl->super.complete_start_word);
}
static void
input_rl_start (struct input *input, const char *program_name)
@ -638,6 +652,8 @@ input_el_install_prompt (struct input_el *self)
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
static unsigned char input_el_on_complete (EditLine *editline, int key);
static void
input_el_start (struct input *input, const char *program_name)
{
@ -665,7 +681,9 @@ input_el_start (struct input *input, const char *program_name)
"run-editor", "Run editor to edit line", input_el_on_run_editor);
el_set (self->editline, EL_BIND, "M-e", "run-editor", NULL);
// TODO: implement method name completion for editline (see degesch)
el_set (self->editline, EL_ADDFN,
"complete", "Complete word", input_el_on_complete);
el_set (self->editline, EL_BIND, "\t", "complete", NULL);
// Source the user's defaults file
el_source (self->editline, NULL);
@ -795,6 +813,121 @@ input_el_ding (struct input *input)
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
static int
input_el_collate (const void *a, const void *b)
{
return strcoll (*(const char **) a, *(const char **) b);
}
static struct strv
input_el_collect_candidates (struct input_el *self, const char *word)
{
struct strv v = strv_make ();
int i = 0; char *candidate = NULL;
while ((candidate = self->super.complete_start_word (word, i++)))
strv_append_owned (&v, candidate);
qsort (v.vector, v.len, sizeof *v.vector, input_el_collate);
return v;
}
static void
input_el_print_candidates (struct input_el *self, const struct strv *v)
{
EditLine *editline = self->editline;
// This insanity seems to be required to make it reprint the prompt
const LineInfoW *info = el_wline (editline);
int from_cursor_until_end = info->lastchar - info->cursor;
el_cursor (editline, from_cursor_until_end);
el_insertstr (editline, "\n");
input_el_redisplay (self);
el_wdeletestr (editline, 1);
el_set (editline, EL_REFRESH);
input_el_hide (&self->super);
for (size_t i = 0; i < v->len; i++)
printf ("%s\n", v->vector[i]);
input_el_show (&self->super);
el_cursor (editline, -from_cursor_until_end);
}
static void
input_el_insert_common_prefix (EditLine *editline, const struct strv *v)
{
char *p[v->len]; memcpy (p, v->vector, sizeof p);
mbstate_t state[v->len]; memset (state, 0, sizeof state);
wchar_t want[2] = {}; size_t len;
while ((len = mbrtowc (&want[0], p[0], strlen (p[0]), &state[0])) > 0)
{
p[0] += len;
for (size_t i = 1; i < v->len; i++)
{
wchar_t found = 0;
if ((len = mbrtowc (&found, p[i], strlen (p[i]), &state[i])) <= 0
|| found != want[0])
return;
p[i] += len;
}
el_winsertstr (editline, want);
}
}
static unsigned char
input_el_on_complete (EditLine *editline, int key)
{
(void) key;
struct input_el *self;
el_get (editline, EL_CLIENTDATA, &self);
// First prepare what Readline would have normally done for us...
const LineInfo *info_mb = el_line (editline);
int len = info_mb->lastchar - info_mb->buffer;
int point = info_mb->cursor - info_mb->buffer;
char *word = xstrndup (info_mb->buffer, len);
int start = point;
while (start && !isspace_ascii (word[start - 1]))
start--;
// Only complete the first word, when we're at the end of it
if (start != 0
|| (word[point] && !isspace_ascii (word[point]))
|| (point && isspace_ascii (word[point - 1])))
{
free (word);
return CC_REFRESH_BEEP;
}
word[point] = '\0';
int word_len = mbstowcs (NULL, word, 0);
struct strv v = input_el_collect_candidates (self, word);
free (word);
if (!v.len)
{
strv_free (&v);
return CC_REFRESH_BEEP;
}
// Remove the original word and replace it with the best (sub)match
el_wdeletestr (editline, word_len);
if (v.len == 1)
{
el_insertstr (editline, v.vector[0]);
el_insertstr (editline, " ");
strv_free (&v);
return CC_REFRESH;
}
input_el_insert_common_prefix (editline, &v);
input_el_print_candidates (self, &v);
strv_free (&v);
return CC_REFRESH_BEEP;
}
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
static bool
input_el_load_history (struct input *input, const char *filename,
struct error **e)
@ -3127,12 +3260,8 @@ init_openrpc (struct app_context *ctx)
str_free (&buf);
}
// --- GNU Readline user actions -----------------------------------------------
#ifdef HAVE_READLINE
static char *
app_readline_complete (const char *text, int state)
complete_method_name (const char *text, int state)
{
static struct str_map_iter iter;
if (!state)
@ -3156,22 +3285,6 @@ app_readline_complete (const char *text, int state)
return match;
}
static char **
app_readline_completion (const char *text, int start, int end)
{
(void) end;
// Only customize matches for the first token, which is the method name
if (start)
return NULL;
// Don't iterate over filenames and stuff in this case
rl_attempted_completion_over = true;
return rl_completion_matches (text, app_readline_complete);
}
#endif // HAVE_READLINE
// --- Main program ------------------------------------------------------------
// The ability to use an external editor on the input line has been shamelessly
@ -3499,6 +3612,7 @@ main (int argc, char *argv[])
g_ctx.input->user_data = &g_ctx;
g_ctx.input->on_input = process_input;
g_ctx.input->on_run_editor = run_editor;
g_ctx.input->complete_start_word = complete_method_name;
g_ctx.methods = str_map_make (NULL);
init_colors (&g_ctx);