fix: #19 do not smash repeated separators

.github/workflows/build.yml

@@ -40,6 +40,7 @@ jobs:
  make test suite=reverse
  make test suite=split_part
  make test suite=stats
+ make test suite=text
 
  - name: Build for Windows
  if: matrix.os == 'windows-latest'

docs/text.md

@@ -21,6 +21,8 @@ Splits `source` string on `sep` and returns the given `part` (counting from one)
 ```
 sqlite> select split_part('one;two;three', ';', 2);
 two
+sqlite> select split_part('one;;three', ';', 2);
+
 ```
 
 If `sep` is composed of multiple characters, each character is treated as separator. E.g.:

src/sqlite3-text.c

@@ -163,9 +163,6 @@ static char *split_part(char *source, const char *sep, int64_t part) {
  char *token;
  int64_t index = 1;
  while ((token = str_sep(&source, sep)) != NULL) {
- if (strcmp(token, "") == 0) {
- continue;
- }
  if (index == part) {
  break;
  }

test/text.sql

@@ -0,0 +1,7 @@
+.load dist/unicode
+.load dist/text
+select '01', split_part('one,two,three', ',', 2) = 'two';
+select '02', split_part('один,два,три', ',', 3) = 'три';
+select '03', split_part('one,,,four', ',', 2) = '';
+select '04', split_part('one,,,four', ',', 4) = 'four';
+select '05', split_part('one/two|three', '/|', 2) = 'two';