Run with --all-features first, run with biggest feature combination early (first or second) if --all-features case is skipped

src/cli.rs

@@ -586,11 +586,8 @@ impl Args {
 
         // https://github.com/taiki-e/cargo-hack/issues/42
         // https://github.com/rust-lang/cargo/pull/8799
-        let namespaced_features = has_z_flag(&cargo_args, "namespaced-features");
         exclude_no_default_features |= !include_features.is_empty();
-        exclude_all_features |= !include_features.is_empty()
-            || !exclude_features.is_empty()
-            || (feature_powerset && !namespaced_features && depth.is_none());
+        exclude_all_features |= !include_features.is_empty() || !exclude_features.is_empty();
         exclude_features.extend_from_slice(&features);
 
         term::verbose::set(verbose != 0);
@@ -668,25 +665,6 @@ fn parse_grouped_features(
     Ok(group_features)
 }
 
-fn has_z_flag(args: &[String], name: &str) -> bool {
-    let mut iter = args.iter().map(String::as_str);
-    while let Some(mut arg) = iter.next() {
-        if arg == "-Z" {
-            arg = iter.next().unwrap();
-        } else if let Some(a) = arg.strip_prefix("-Z") {
-            arg = a;
-        } else {
-            continue;
-        }
-        if let Some(rest) = arg.strip_prefix(name) {
-            if rest.is_empty() || rest.starts_with('=') {
-                return true;
-            }
-        }
-    }
-    false
-}
-
 // (short flag, long flag, value name, short descriptions, additional descriptions)
 type HelpText<'a> = (&'a str, &'a str, &'a str, &'a str, &'a [&'a str]);
 

src/main.rs

@@ -264,11 +264,13 @@ fn determine_kind<'a>(
             let kind = Kind::Normal;
             Some(PackageRuns { id, kind, feature_count })
         } else {
+            // See exec_on_package
             let feature_count = features.len()
                 + usize::from(!cx.exclude_no_default_features)
                 + usize::from(
-                    !cx.exclude_all_features
-                        && pkg_features.normal().len() + pkg_features.optional_deps().len() > 1,
+                    !(cx.exclude_all_features
+                        || pkg_features.optional_deps().is_empty()
+                            && pkg_features.normal().len() <= 1),
                 );
             let kind = Kind::Each { features };
             Some(PackageRuns { id, kind, feature_count })
@@ -290,11 +292,17 @@ fn determine_kind<'a>(
             let kind = Kind::Normal;
             Some(PackageRuns { id, kind, feature_count })
         } else {
+            // See exec_on_package
             let feature_count = features.len()
                 + usize::from(!cx.exclude_no_default_features)
                 + usize::from(
-                    !cx.exclude_all_features
-                        && pkg_features.normal().len() + pkg_features.optional_deps().len() > 1,
+                    !(cx.exclude_all_features
+                        || (pkg_features.optional_deps().is_empty()
+                            || match &cx.optional_deps {
+                                // Skip when all optional deps are already included in powerset
+                                Some(opt_deps) => opt_deps.is_empty(),
+                                None => false,
+                            })),
                 );
             let kind = Kind::Powerset { features };
             Some(PackageRuns { id, kind, feature_count })
@@ -477,6 +485,34 @@ fn exec_on_package(
         Kind::Each { .. } | Kind::Powerset { .. } => {}
     }
 
+    // Run with --all-features first: https://github.com/taiki-e/cargo-hack/issues/246
+    // https://github.com/taiki-e/cargo-hack/issues/42
+    // https://github.com/rust-lang/cargo/pull/8799
+    // > --all-features will now enable features for inactive optional dependencies.
+    let pkg_features = cx.pkg_features(id);
+    let exclude_all_features = cx.exclude_all_features
+        || match kind {
+            Kind::Each { .. } => {
+                pkg_features.optional_deps().is_empty() && pkg_features.normal().len() <= 1
+            }
+            Kind::Powerset { .. } => {
+                pkg_features.optional_deps().is_empty()
+                    || match &cx.optional_deps {
+                        // Skip when all optional deps are already included in powerset
+                        Some(opt_deps) => opt_deps.is_empty() && cx.depth.is_none(),
+                        None => false,
+                    }
+            }
+            Kind::Normal => unreachable!(),
+        };
+    if !exclude_all_features {
+        let mut line = line.clone();
+        // run with all features
+        // https://github.com/taiki-e/cargo-hack/issues/42
+        line.arg("--all-features");
+        exec_cargo(cx, id, &mut line, progress, keep_going)?;
+    }
+
     if !cx.no_default_features {
         line.arg("--no-default-features");
     }
@@ -498,23 +534,25 @@ fn exec_on_package(
             }
         }
         Kind::Powerset { features } => {
+            let features =
+                if exclude_all_features && features.len() > 1 && cx.depth.unwrap_or(usize::MAX) > 1
+                {
+                    // If --all-features case is skipped, run with the biggest feature combination early (first or second): https://github.com/taiki-e/cargo-hack/issues/246
+                    // TODO: The last combination is usually the biggest feature combination,
+                    // but in some cases this is not the case due to deduplication of the powerset.
+                    let last = features.last().unwrap();
+                    exec_cargo_with_features(cx, id, &line, progress, keep_going, last)?;
+                    &features[..features.len() - 1]
+                } else {
+                    features
+                };
             for f in features {
                 exec_cargo_with_features(cx, id, &line, progress, keep_going, f)?;
             }
         }
         Kind::Normal => unreachable!(),
     }
 
-    let pkg_features = cx.pkg_features(id);
-    if !cx.exclude_all_features
-        && pkg_features.normal().len() + pkg_features.optional_deps().len() > 1
-    {
-        // run with all features
-        // https://github.com/taiki-e/cargo-hack/issues/42
-        line.arg("--all-features");
-        exec_cargo(cx, id, &mut line, progress, keep_going)?;
-    }
-
     Ok(())
 }