refactor(clean): Better divide old / new layout (#16304)

### What does this PR try to resolve?

A follow up to #16300.

This doesn't split out any functions
- The stuff before hand is quite significant
- For #16264, we made add more before and some after
- We could pull out only the branches of the `if` into functions but
then we'd just move them back when this is done and seems like extra
churn

### How to test and review this PR?

Author: weihanglo

src/cargo/ops/cargo_clean.rs

@@ -192,19 +192,17 @@ fn clean_specs(
 
     clean_ctx.progress = Box::new(CleaningPackagesBar::new(clean_ctx.gctx, packages.len()));
 
-    // Try to reduce the amount of times we iterate over the same target directory by storing away
-    // the directories we've iterated over (and cleaned for a given package).
-    let mut cleaned_packages: HashMap<_, HashSet<_>> = HashMap::default();
-    for pkg in packages {
-        let pkg_dir = format!("{}-*", pkg.name());
-        clean_ctx.progress.on_cleaning_package(&pkg.name())?;
-
-        if clean_ctx.gctx.cli_unstable().build_dir_new_layout {
+    if clean_ctx.gctx.cli_unstable().build_dir_new_layout {
+        for pkg in packages {
+            clean_ctx.progress.on_cleaning_package(&pkg.name())?;
+
+            // Remove intermediate artifacts
             for (_compile_kind, layout) in &layouts_with_host {
                 let dir = layout.build_dir().build_unit(&pkg.name());
                 clean_ctx.rm_rf(&dir)?;
             }
 
+            // Remove the uplifted copy.
             for target in pkg.targets() {
                 if target.is_custom_build() {
                     continue;
@@ -230,7 +228,6 @@ fn clean_specs(
                             TargetKind::Test | TargetKind::Bench => None,
                             _ => Some(artifact_dir.dest()),
                         };
-                        // Remove the uplifted copy.
                         if let Some(uplift_dir) = uplift_dir {
                             for file_type in file_types {
                                 let uplifted_path =
@@ -244,102 +241,112 @@ fn clean_specs(
                     }
                 }
             }
-            continue;
-        }
-
-        // Clean fingerprints.
-        for (_, layout) in &layouts_with_host {
-            let dir = escape_glob_path(layout.build_dir().legacy_fingerprint())?;
-            clean_ctx
-                .rm_rf_package_glob_containing_hash(&pkg.name(), &Path::new(&dir).join(&pkg_dir))?;
         }
+    } else {
+        // Try to reduce the amount of times we iterate over the same target directory by storing away
+        // the directories we've iterated over (and cleaned for a given package).
+        let mut cleaned_packages: HashMap<_, HashSet<_>> = HashMap::default();
+        for pkg in packages {
+            let pkg_dir = format!("{}-*", pkg.name());
+            clean_ctx.progress.on_cleaning_package(&pkg.name())?;
+
+            // Clean fingerprints.
+            for (_, layout) in &layouts_with_host {
+                let dir = escape_glob_path(layout.build_dir().legacy_fingerprint())?;
+                clean_ctx.rm_rf_package_glob_containing_hash(
+                    &pkg.name(),
+                    &Path::new(&dir).join(&pkg_dir),
+                )?;
+            }
 
-        for target in pkg.targets() {
-            if target.is_custom_build() {
-                // Get both the build_script_build and the output directory.
-                for (_, layout) in &layouts_with_host {
-                    let dir = escape_glob_path(layout.build_dir().build())?;
-                    clean_ctx.rm_rf_package_glob_containing_hash(
-                        &pkg.name(),
-                        &Path::new(&dir).join(&pkg_dir),
-                    )?;
+            for target in pkg.targets() {
+                if target.is_custom_build() {
+                    // Get both the build_script_build and the output directory.
+                    for (_, layout) in &layouts_with_host {
+                        let dir = escape_glob_path(layout.build_dir().build())?;
+                        clean_ctx.rm_rf_package_glob_containing_hash(
+                            &pkg.name(),
+                            &Path::new(&dir).join(&pkg_dir),
+                        )?;
+                    }
+                    continue;
                 }
-                continue;
-            }
-            let crate_name: Rc<str> = target.crate_name().into();
-            let path_dot: &str = &format!("{crate_name}.");
-            let path_dash: &str = &format!("{crate_name}-");
-            for &mode in &[
-                CompileMode::Build,
-                CompileMode::Test,
-                CompileMode::Check { test: false },
-            ] {
-                for (compile_kind, layout) in &layouts {
-                    let triple = target_data.short_name(compile_kind);
-                    let (file_types, _unsupported) = target_data
-                        .info(*compile_kind)
-                        .rustc_outputs(mode, target.kind(), triple, clean_ctx.gctx)?;
-                    let artifact_dir = layout
-                        .artifact_dir()
-                        .expect("artifact-dir was not locked during clean");
-                    let (dir, uplift_dir) = match target.kind() {
-                        TargetKind::ExampleBin | TargetKind::ExampleLib(..) => {
-                            (layout.build_dir().examples(), Some(artifact_dir.examples()))
+                let crate_name: Rc<str> = target.crate_name().into();
+                let path_dot: &str = &format!("{crate_name}.");
+                let path_dash: &str = &format!("{crate_name}-");
+                for &mode in &[
+                    CompileMode::Build,
+                    CompileMode::Test,
+                    CompileMode::Check { test: false },
+                ] {
+                    for (compile_kind, layout) in &layouts {
+                        let triple = target_data.short_name(compile_kind);
+                        let (file_types, _unsupported) = target_data
+                            .info(*compile_kind)
+                            .rustc_outputs(mode, target.kind(), triple, clean_ctx.gctx)?;
+                        let artifact_dir = layout
+                            .artifact_dir()
+                            .expect("artifact-dir was not locked during clean");
+                        let (dir, uplift_dir) = match target.kind() {
+                            TargetKind::ExampleBin | TargetKind::ExampleLib(..) => {
+                                (layout.build_dir().examples(), Some(artifact_dir.examples()))
+                            }
+                            // Tests/benchmarks are never uplifted.
+                            TargetKind::Test | TargetKind::Bench => {
+                                (layout.build_dir().legacy_deps(), None)
+                            }
+                            _ => (layout.build_dir().legacy_deps(), Some(artifact_dir.dest())),
+                        };
+                        let mut dir_glob_str = escape_glob_path(dir)?;
+                        let dir_glob = Path::new(&dir_glob_str);
+                        for file_type in file_types {
+                            // Some files include a hash in the filename, some don't.
+                            let hashed_name = file_type.output_filename(target, Some("*"));
+                            let unhashed_name = file_type.output_filename(target, None);
+
+                            clean_ctx.rm_rf_glob(&dir_glob.join(&hashed_name))?;
+                            clean_ctx.rm_rf(&dir.join(&unhashed_name))?;
+
+                            // Remove the uplifted copy.
+                            if let Some(uplift_dir) = uplift_dir {
+                                let uplifted_path =
+                                    uplift_dir.join(file_type.uplift_filename(target));
+                                clean_ctx.rm_rf(&uplifted_path)?;
+                                // Dep-info generated by Cargo itself.
+                                let dep_info = uplifted_path.with_extension("d");
+                                clean_ctx.rm_rf(&dep_info)?;
+                            }
                         }
-                        // Tests/benchmarks are never uplifted.
-                        TargetKind::Test | TargetKind::Bench => {
-                            (layout.build_dir().legacy_deps(), None)
+                        let unhashed_dep_info = dir.join(format!("{}.d", crate_name));
+                        clean_ctx.rm_rf(&unhashed_dep_info)?;
+
+                        if !dir_glob_str.ends_with(std::path::MAIN_SEPARATOR) {
+                            dir_glob_str.push(std::path::MAIN_SEPARATOR);
                         }
-                        _ => (layout.build_dir().legacy_deps(), Some(artifact_dir.dest())),
-                    };
-                    let mut dir_glob_str = escape_glob_path(dir)?;
-                    let dir_glob = Path::new(&dir_glob_str);
-                    for file_type in file_types {
-                        // Some files include a hash in the filename, some don't.
-                        let hashed_name = file_type.output_filename(target, Some("*"));
-                        let unhashed_name = file_type.output_filename(target, None);
-
-                        clean_ctx.rm_rf_glob(&dir_glob.join(&hashed_name))?;
-                        clean_ctx.rm_rf(&dir.join(&unhashed_name))?;
-
-                        // Remove the uplifted copy.
-                        if let Some(uplift_dir) = uplift_dir {
-                            let uplifted_path = uplift_dir.join(file_type.uplift_filename(target));
-                            clean_ctx.rm_rf(&uplifted_path)?;
-                            // Dep-info generated by Cargo itself.
-                            let dep_info = uplifted_path.with_extension("d");
-                            clean_ctx.rm_rf(&dep_info)?;
+                        dir_glob_str.push('*');
+                        let dir_glob_str: Rc<str> = dir_glob_str.into();
+                        if cleaned_packages
+                            .entry(dir_glob_str.clone())
+                            .or_default()
+                            .insert(crate_name.clone())
+                        {
+                            let paths = [
+                                // Remove dep-info file generated by rustc. It is not tracked in
+                                // file_types. It does not have a prefix.
+                                (path_dash, ".d"),
+                                // Remove split-debuginfo files generated by rustc.
+                                (path_dot, ".o"),
+                                (path_dot, ".dwo"),
+                                (path_dot, ".dwp"),
+                            ];
+                            clean_ctx.rm_rf_prefix_list(&dir_glob_str, &paths)?;
                         }
-                    }
-                    let unhashed_dep_info = dir.join(format!("{}.d", crate_name));
-                    clean_ctx.rm_rf(&unhashed_dep_info)?;
 
-                    if !dir_glob_str.ends_with(std::path::MAIN_SEPARATOR) {
-                        dir_glob_str.push(std::path::MAIN_SEPARATOR);
+                        // TODO: what to do about build_script_build?
+                        let dir = escape_glob_path(layout.build_dir().incremental())?;
+                        let incremental = Path::new(&dir).join(format!("{}-*", crate_name));
+                        clean_ctx.rm_rf_glob(&incremental)?;
                     }
-                    dir_glob_str.push('*');
-                    let dir_glob_str: Rc<str> = dir_glob_str.into();
-                    if cleaned_packages
-                        .entry(dir_glob_str.clone())
-                        .or_default()
-                        .insert(crate_name.clone())
-                    {
-                        let paths = [
-                            // Remove dep-info file generated by rustc. It is not tracked in
-                            // file_types. It does not have a prefix.
-                            (path_dash, ".d"),
-                            // Remove split-debuginfo files generated by rustc.
-                            (path_dot, ".o"),
-                            (path_dot, ".dwo"),
-                            (path_dot, ".dwp"),
-                        ];
-                        clean_ctx.rm_rf_prefix_list(&dir_glob_str, &paths)?;
-                    }
-
-                    // TODO: what to do about build_script_build?
-                    let dir = escape_glob_path(layout.build_dir().incremental())?;
-                    let incremental = Path::new(&dir).join(format!("{}-*", crate_name));
-                    clean_ctx.rm_rf_glob(&incremental)?;
                 }
             }
         }