read-cache & fetch-negotiator: check "enum" values in switch()

avar · gitster · commit f1bee828734c · 2021-09-22T13:15:00.000-07:00
Change tweak_untracked_cache() in "read-cache.c" to use a switch() to have the compiler assert that we checked all possible values in the "enum untracked_cache_setting" type, and likewise remove the "default" case in fetch_negotiator_init() in favor of checking for "FETCH_NEGOTIATION_UNSET" and "FETCH_NEGOTIATION_NONE". As will be discussed in a subsequent we'll only ever have either of these set to FETCH_NEGOTIATION_NONE, FETCH_NEGOTIATION_UNSET and UNTRACKED_CACHE_UNSET within the prepare_repo_settings() function itself. In preparation for fixing that code let's add a BUG() here to mark this as unreachable code. See ad0fb65 (repo-settings: parse core.untrackedCache, 2019-08-13) for when the "unset" and "keep" handling for core.untrackedCache was consolidated, and aaf633c (repo-settings: create feature.experimental setting, 2019-08-13) for the addition of the "default" pattern in "fetch-negotiator.c". Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/fetch-negotiator.c b/fetch-negotiator.c
@@ -19,8 +19,10 @@ void fetch_negotiator_init(struct repository *r,
 		return;
 
 	case FETCH_NEGOTIATION_DEFAULT:
-	default:
 		default_negotiator_init(negotiator);
 		return;
+	case FETCH_NEGOTIATION_NONE:
+	case FETCH_NEGOTIATION_UNSET:
+		BUG("FETCH_NEGOTIATION_{NONE,UNSET} used outside of prepare_repo_settings()!");
 	}
 }
diff --git a/read-cache.c b/read-cache.c
@@ -1944,13 +1944,18 @@ static void tweak_untracked_cache(struct index_state *istate)
 
 	prepare_repo_settings(r);
 
-	if (r->settings.core_untracked_cache  == UNTRACKED_CACHE_REMOVE) {
+	switch (r->settings.core_untracked_cache) {
+	case UNTRACKED_CACHE_REMOVE:
 		remove_untracked_cache(istate);
-		return;
-	}
-
-	if (r->settings.core_untracked_cache == UNTRACKED_CACHE_WRITE)
+		break;
+	case UNTRACKED_CACHE_WRITE:
 		add_untracked_cache(istate);
+		break;
+	case UNTRACKED_CACHE_KEEP:
+		break;
+	case UNTRACKED_CACHE_UNSET:
+		BUG("UNTRACKED_CACHE_UNSET used outside of prepare_repo_settings()!");
+	}
 }
 
 static void tweak_split_index(struct index_state *istate)

Original file line number	Diff line number	Diff line change
`@@ -19,8 +19,10 @@ void fetch_negotiator_init(struct repository *r,`
`19`	`19`	`return;`
`20`	`20`
`21`	`21`	`case FETCH_NEGOTIATION_DEFAULT:`
`22`		`- default:`
`23`	`22`	`default_negotiator_init(negotiator);`
`24`	`23`	`return;`
	`24`	`+ case FETCH_NEGOTIATION_NONE:`
	`25`	`+ case FETCH_NEGOTIATION_UNSET:`
	`26`	`+ BUG("FETCH_NEGOTIATION_{NONE,UNSET} used outside of prepare_repo_settings()!");`
`25`	`27`	`}`
`26`	`28`	`}`