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Co-authored-by: Qix <Qix-@users.noreply.github.com>

include/git2/remote.h

@@ -744,9 +744,9 @@ typedef struct {
 	git_proxy_options proxy_opts;
 
 	/**
-	 * Depth of the fetch to perform, has to be a positive integer.
+	 * Depth of the fetch to perform. Depth <= 0 fetches the full history.
 	 *
-	 * The default is -1, which will fetch the full history.
+	 * The default is -1.
 	 */
 	int depth;
 

src/libgit2/transports/smart_protocol.c

@@ -359,7 +359,7 @@ static int cap_not_sup_err(const char *cap_name)
 /* Disables server capabilities we're not interested in */
 static int setup_caps(transport_smart_caps *caps, const git_fetch_negotiation *wants)
 {
-	if (wants->depth) {
+	if (wants->depth > 0) {
 		if (!caps->shallow)
 			return cap_not_sup_err(GIT_CAP_SHALLOW);
 	} else {