feat(cli): --fuzzy honors an explicit --no-incremental

The --fuzzy implication previously forced use_incremental back on even when
the user passed --no-incremental, while --no-delta and -W were honored.
Track a --no-incremental latch (like the no_delta latch): with it set, do not
force the handshake on, and because delta needs the handshake, also suppress
the delta implication so no invalid '--delta requires --incremental' config
results.  A --fuzzy --no-incremental run is therefore a plain default-mode
transfer (fuzzy inert), consistent with -W/--no-delta.  Documented in the
usage text (this deliberately differs from the basis-dir options, which still
force incremental unconditionally).

src/client/client_cli.c

@@ -610,9 +610,11 @@ static int apply_table_option(Config* config, const OptionEntry* entry, const ch
 int parse_args(Config* config, int argc, char* argv[], int* positional_args,
                int* positional_count) {
   bool verbose = false;
-  /* --no-delta seen on the command line: the user explicitly switched the
+  /* Explicit --no-delta / --no-incremental seen on the command line: the user
-     delta machinery off, so the --fuzzy implication must not override it. */
+     switched part of the delta machinery off, so the --fuzzy implication must
+     not silently turn it back on. */
   bool no_delta = false;
+  bool no_incremental = false;
   protocol_set_8_bit_output(config->eight_bit_output);
 
   /* Apply output controls before processing other options so their order is irrelevant. */
@@ -644,6 +646,8 @@ int parse_args(Config* config, int argc, char* argv[], int* positional_args,
     if (strncmp(argv[i], "--no-", strlen("--no-")) == 0) {
       if (strcmp(argv[i], "--no-delta") == 0)
         no_delta = true;
+      else if (strcmp(argv[i], "--no-incremental") == 0)
+        no_incremental = true;
       if (apply_negation(config, argv[i]) != 0)
         return -1;
       continue;
@@ -1077,14 +1081,19 @@ int parse_args(Config* config, int argc, char* argv[], int* positional_args,
 
   /* -y/--fuzzy reuses an existing similar-named destination file as the delta
    * basis, so it is meaningless without the receiver-driven delta path:
-   * imply --incremental, and --delta unless --whole-file (or an explicit
+   * imply --incremental and --delta unless --whole-file or an explicit
-   * --no-delta) switched the delta machinery off.  FastSync has delta OFF by
+   * --no-delta / --no-incremental switched the machinery off.  FastSync has
-   * default (unlike rsync), so a bare --fuzzy must turn it on or it would be
+   * delta OFF by default (unlike rsync), so a bare --fuzzy must turn it on or
-   * a silent no-op.  --whole-file/--no-delta after --fuzzy therefore leave
+   * it would be a silent no-op.  -W/--no-delta/--no-incremental therefore
-   * fuzzy inert, matching rsync where --fuzzy only affects delta transfers. */
+   * leave fuzzy inert, matching rsync where --whole-file makes fuzzy
+   * irrelevant (note: unlike the basis-dir options, --fuzzy honors an
+   * explicit --no-incremental instead of forcing the handshake back on). */
   if (config->fuzzy) {
-    config->use_incremental = true;
+    if (!no_incremental)
-    if (!config->whole_file && !no_delta)
+      config->use_incremental = true;
+    /* Delta needs the incremental per-file handshake, so an explicit
+     * --no-incremental also suppresses the delta implication. */
+    if (!config->whole_file && !no_delta && !no_incremental)
       config->use_delta = true;
   }
 

src/client/usage.c

@@ -84,7 +84,8 @@ void print_usage(void) {
   printf("  -y, --fuzzy         Use a similar-named file already in the destination\n");
   printf("                    directory as the delta basis when the destination has no\n");
   printf("                    usable file at the exact path (saves bandwidth; implies\n");
-  printf("                    --incremental and --delta; inert with --whole-file)\n");
+  printf("                    --incremental and --delta; inert with --whole-file,\n");
+  printf("                    --no-delta, or --no-incremental)\n");
   printf("  --no-fuzzy          Disable --fuzzy\n");
   printf("  --delta-block <n>   Delta block size in bytes (default: %d)\n",
          DELTA_BLOCK_SIZE_DEFAULT);