lib: make notmuch_query_add_tag_exclude return a status value

Since this is an ABI breaking change, but we already bumped the SONAME
for the next release

lib/notmuch.h

@@ -179,6 +179,11 @@ typedef enum _notmuch_status {
      * passed to a function expecting an absolute path.
      */
     NOTMUCH_STATUS_PATH_ERROR,
+    /**
+     * The requested operation was ignored. Depending on the function,
+     * this may not be an actual error.
+     */
+    NOTMUCH_STATUS_IGNORED,
     /**
      * One of the arguments violates the preconditions for the
      * function, in a way not covered by a more specific argument.
@@ -812,10 +817,20 @@ notmuch_query_get_sort (const notmuch_query_t *query);
 
 /**
  * Add a tag that will be excluded from the query results by default.
- * This exclusion will be overridden if this tag appears explicitly in
+ * This exclusion will be ignored if this tag appears explicitly in
  * the query.
+ *
+ * @returns
+ *
+ * NOTMUCH_STATUS_SUCCESS: excluded was added successfully.
+ *
+ * NOTMUCH_STATUS_XAPIAN_EXCEPTION: a Xapian exception occured.
+ *      Most likely a problem lazily parsing the query string.
+ *
+ * NOTMUCH_STATUS_IGNORED: tag is explicitely present in the query, so
+ *		not excluded.
  */
-void
+notmuch_status_t
 notmuch_query_add_tag_exclude (notmuch_query_t *query, const char *tag);
 
 /**

lib/query.cc

@@ -177,29 +177,22 @@ notmuch_query_get_sort (const notmuch_query_t *query)
     return query->sort;
 }
 
-void
+notmuch_status_t
 notmuch_query_add_tag_exclude (notmuch_query_t *query, const char *tag)
 {
     notmuch_status_t status;
     char *term;
 
     status = _notmuch_query_ensure_parsed (query);
-    /* The following is not ideal error handling, but to avoid
-     * breaking the ABI, we can live with it for now. In particular at
-     * least in the notmuch CLI, any syntax error in the query is
-     * caught in a later call to _notmuch_query_ensure_parsed with a
-     * better error path.
-     *
-     * TODO: add status return to this function.
-     */
     if (status)
-	return;
+	return status;
 
     term = talloc_asprintf (query, "%s%s", _find_prefix ("tag"), tag);
     if (query->terms.count(term) != 0)
-	return; /* XXX report ignoring exclude? */
+	return NOTMUCH_STATUS_IGNORED;
 
     _notmuch_string_list_append (query->exclude_terms, term);
+    return NOTMUCH_STATUS_SUCCESS;
 }
 
 /* We end up having to call the destructors explicitly because we had

notmuch-count.c

@@ -87,8 +87,13 @@ print_count (notmuch_database_t *notmuch, const char *query_str,
 	return -1;
     }
 
-    for (i = 0; i < exclude_tags_length; i++)
+    for (i = 0; i < exclude_tags_length; i++) {
-	notmuch_query_add_tag_exclude (query, exclude_tags[i]);
+	status = notmuch_query_add_tag_exclude (query, exclude_tags[i]);
+	if (status && status != NOTMUCH_STATUS_IGNORED) {
+	    print_status_query ("notmuch count", query, status);
+	    return -1;
+	}
+    }
 
     switch (output) {
     case OUTPUT_MESSAGES:

notmuch-search.c

@@ -735,11 +735,19 @@ _notmuch_search_prepare (search_context_t *ctx, notmuch_config_t *config, int ar
     if (ctx->exclude != NOTMUCH_EXCLUDE_FALSE) {
 	const char **search_exclude_tags;
 	size_t search_exclude_tags_length;
+	notmuch_status_t status;
 
 	search_exclude_tags = notmuch_config_get_search_exclude_tags
 	    (config, &search_exclude_tags_length);
-	for (i = 0; i < search_exclude_tags_length; i++)
+
-	    notmuch_query_add_tag_exclude (ctx->query, search_exclude_tags[i]);
+	for (i = 0; i < search_exclude_tags_length; i++) {
+	    status = notmuch_query_add_tag_exclude (ctx->query, search_exclude_tags[i]);
+	    if (status && status != NOTMUCH_STATUS_IGNORED) {
+		print_status_query ("notmuch search", ctx->query, status);
+		return EXIT_FAILURE;
+	    }
+	}
+
 	notmuch_query_set_omit_excluded (ctx->query, ctx->exclude);
     }
 

notmuch-show.c

@@ -1177,11 +1177,19 @@ notmuch_show_command (notmuch_config_t *config, int argc, char *argv[])
 	const char **search_exclude_tags;
 	size_t search_exclude_tags_length;
 	unsigned int i;
+	notmuch_status_t status;
 
 	search_exclude_tags = notmuch_config_get_search_exclude_tags
 	    (config, &search_exclude_tags_length);
-	for (i = 0; i < search_exclude_tags_length; i++)
+
-	    notmuch_query_add_tag_exclude (query, search_exclude_tags[i]);
+	for (i = 0; i < search_exclude_tags_length; i++) {
+	    status = notmuch_query_add_tag_exclude (query, search_exclude_tags[i]);
+	    if (status && status != NOTMUCH_STATUS_IGNORED) {
+		print_status_query ("notmuch show", query, status);
+		ret = -1;
+		goto DONE;
+	    }
+	}
 
 	if (exclude == EXCLUDE_FALSE) {
 	    notmuch_query_set_omit_excluded (query, FALSE);
@@ -1191,6 +1199,7 @@ notmuch_show_command (notmuch_config_t *config, int argc, char *argv[])
 	ret = do_show (config, query, formatter, sprinter, &params);
     }
 
+ DONE:
     notmuch_crypto_cleanup (&params.crypto);
     notmuch_query_destroy (query);
     notmuch_database_destroy (notmuch);