fix(discover): report a symlink skip through the ignored-files taxonomy

src/discover/discover.c

@@ -754,14 +754,18 @@ static int wide_stat(const char *path, struct stat *st) {
 /* Stat a path, skipping symlinks (POSIX) and junctions / reparse points
  * (Windows). Returns 0 on success, -1 to skip. Skipping reparse points keeps
  * discovery from walking through a junction that points outside the project
- * root, mirroring the POSIX S_ISLNK skip. */
-static int safe_stat(const char *abs_path, struct stat *st) {
+ * root, mirroring the POSIX S_ISLNK skip. *is_symlink reports whether the
+ * skip (if any) was specifically the symlink/reparse-point check, as
+ * opposed to some other stat failure (permissions, a race with a delete). */
+static int safe_stat(const char *abs_path, struct stat *st, bool *is_symlink) {
+    *is_symlink = false;
 #ifdef _WIN32
     wchar_t *wpath = cbm_path_to_wide(abs_path);
     if (wpath) {
         DWORD attr = GetFileAttributesW(wpath);
         free(wpath);
         if (attr != INVALID_FILE_ATTRIBUTES && (attr & FILE_ATTRIBUTE_REPARSE_POINT)) {
+            *is_symlink = true;
             return CBM_NOT_FOUND;
         }
     }
@@ -771,6 +775,7 @@ static int safe_stat(const char *abs_path, struct stat *st) {
         return CBM_NOT_FOUND;
     }
     if (S_ISLNK(st->st_mode)) {
+        *is_symlink = true;
         return CBM_NOT_FOUND;
     }
     return 0;
@@ -887,9 +892,15 @@ static void walk_dir_process_entry(cbm_dirent_t *entry, const walk_frame_t *fram
     }
 
     struct stat st;
-    if (safe_stat(abs_path, &st) != 0) {
+    bool is_symlink = false;
+    if (safe_stat(abs_path, &st, &is_symlink) != 0) {
         if (out->count_only) {
             out->failed = true;
+        } else if (is_symlink) {
+            /* Deliberately not indexed (#963): record so callers can
+             * surface it, matching the directory-exclusion and file
+             * skip_reason paths a few lines below. */
+            file_list_add_ignored(out, rel_path, "symlink");
         }
         return;
     }

tests/test_discover.c

@@ -909,6 +909,46 @@ TEST(discover_symlink_skipped) {
 #endif
 }
 
+/* #1815: a symlink skip must be as visible as the other two skip paths in
+ * the same walk (gitignore/cbmignore/skip-list files, excluded dirs): a
+ * subtree dropped because it's a symlink must not look identical to a
+ * complete index. */
+TEST(discover_symlink_skip_is_reported) {
+#ifdef _WIN32
+    SKIP_PLATFORM("Windows: symlinks need admin / symlink() unavailable");
+#else
+    char *base = th_mktempdir("cbm_disc_sym_rep");
+    ASSERT(base != NULL);
+
+    th_write_file(TH_PATH(base, "real.go"), "package main\n");
+    char real_path[512], link_path[512];
+    snprintf(real_path, sizeof(real_path), "%s/real.go", base);
+    snprintf(link_path, sizeof(link_path), "%s/link.go", base);
+    symlink(real_path, link_path);
+
+    cbm_discover_opts_t opts = {0};
+    cbm_file_info_t *files = NULL;
+    int count = 0;
+    cbm_ignored_file_t *ignored = NULL;
+    int ignored_count = 0;
+    int ignored_total = 0;
+
+    int rc = cbm_discover_ex2(base, &opts, &files, &count, NULL, NULL, &ignored, &ignored_count,
+                              &ignored_total);
+    ASSERT_EQ(rc, 0);
+    ASSERT_EQ(count, 1); /* real.go only, same as discover_symlink_skipped */
+    ASSERT_EQ(ignored_total, 1);
+    ASSERT_EQ(ignored_count, 1);
+    ASSERT_STR_EQ(ignored[0].rel_path, "link.go");
+    ASSERT_STR_EQ(ignored[0].reason, "symlink");
+
+    cbm_discover_free(files, count);
+    cbm_discover_free_ignored(ignored, ignored_count);
+    th_cleanup(base);
+    PASS();
+#endif
+}
+
 TEST(discover_new_ignore_patterns) {
     char *base = th_mktempdir("cbm_disc_newign");
     ASSERT(base != NULL);
@@ -1785,6 +1825,7 @@ SUITE(discover) {
     RUN_TEST(discover_cbmignore);
     RUN_TEST(discover_cbmignore_stacks);
     RUN_TEST(discover_symlink_skipped);
+    RUN_TEST(discover_symlink_skip_is_reported);
     RUN_TEST(discover_new_ignore_patterns);
     RUN_TEST(discover_generic_dirs_full_mode);
     RUN_TEST(discover_generic_dirs_fast_mode);