Remove eager fail for update --offline

Author: Revantus

src/cargo/ops/cargo_generate_lockfile.rs

@@ -44,10 +44,6 @@ pub fn update_lockfile(ws: &Workspace<'_>, opts: &UpdateOptions<'_>) -> CargoRes
         anyhow::bail!("you can't generate a lockfile for an empty workspace.")
     }
 
-    if opts.config.offline() && opts.precise.is_none() {
-        anyhow::bail!("you can't update in the offline mode without precise packages");
-    }
-
     // Updates often require a lot of modifications to the registry, so ensure
     // that we're synchronized against other Cargos.
     let _lock = ws.config().acquire_package_cache_lock()?;

tests/testsuite/offline.rs

@@ -564,7 +564,7 @@ fn offline_with_all_patched() {
 }
 
 #[cargo_test]
-fn offline_precise_update() {
+fn offline_update() {
     // Cache a few versions to update against
     let p = project().file("src/lib.rs", "").build();
     let versions = ["1.2.3", "1.2.5", "1.2.9"];
@@ -648,10 +648,20 @@ fn main(){
 ",
         )
         .run();
-    p2.rename_run("foo", "with_1_2_9")
+    p2.rename_run("foo", "with_1_2_3")
         .with_stdout("1.2.3")
         .run();
 
+    // Offline update should only print package details and not index updating
+    p2.cargo("update --offline")
+        .with_status(0)
+        .with_stderr(
+            "\
+[UPDATING] present_dep v1.2.3 -> v1.2.9
+",
+        )
+        .run();
+
     // No v1.2.8 loaded into the cache so expect failure.
     p2.cargo("update -p present_dep --precise 1.2.8 --offline")
         .with_status(101)