feat: option to preserve other component versions in splat directory

src/ctx.rs

@@ -277,21 +277,35 @@ impl Ctx {
 
         let mut splat_config = match &ops {
             crate::Ops::Splat(config) => {
+                if config.preserve_versions && !config.use_winsysroot_style {
+                    anyhow::bail!("preserve_versions requires use_winsysroot_style");
+                }
+
                 let splat_roots = crate::splat::prep_splat(
                     self.clone(),
                     &config.output,
                     config.use_winsysroot_style.then_some(&crt_version),
+                    Some(&sdk_version),
+                    vcrd_version.as_deref(),
+                    config.preserve_versions,
                 )?;
                 let mut config = config.clone();
                 config.output = splat_roots.root.clone();
 
                 Some((splat_roots, config))
             }
             crate::Ops::Minimize(config) => {
+                if config.preserve_versions && !config.use_winsysroot_style {
+                    anyhow::bail!("preserve_versions requires use_winsysroot_style");
+                }
+
                 let splat_roots = crate::splat::prep_splat(
                     self.clone(),
                     &config.splat_output,
                     config.use_winsysroot_style.then_some(&crt_version),
+                    Some(&sdk_version),
+                    vcrd_version.as_deref(),
+                    config.preserve_versions,
                 )?;
 
                 let config = crate::SplatConfig {
@@ -300,6 +314,7 @@ impl Ctx {
                     include_debug_symbols: config.include_debug_symbols,
                     enable_symlinks: config.enable_symlinks,
                     use_winsysroot_style: config.use_winsysroot_style,
+                    preserve_versions: config.preserve_versions,
                     output: splat_roots.root.clone(),
                     map: Some(config.map.clone()),
                     copy: config.copy,

src/main.rs

@@ -65,6 +65,11 @@ pub struct SplatOptions {
     /// and --disable-symlinks for use with clang-cl on Windows.
     #[arg(long)]
     use_winsysroot_style: bool,
+    /// Keep other CRT/SDK/VCR versions already present in the splat output;
+    /// only the version being installed is removed first
+    /// (requires --use-winsysroot-style)
+    #[arg(long, requires = "use_winsysroot_style")]
+    preserve_versions: bool,
 }
 
 #[derive(Subcommand)]
@@ -354,6 +359,7 @@ fn main() -> Result<(), Error> {
             enable_symlinks: !options.disable_symlinks,
             preserve_ms_arch_notation: options.preserve_ms_arch_notation,
             use_winsysroot_style: options.use_winsysroot_style,
+            preserve_versions: options.preserve_versions,
             copy,
             map,
             output: output.unwrap_or_else(|| ctx.work_dir.join("splat")),
@@ -373,6 +379,7 @@ fn main() -> Result<(), Error> {
             enable_symlinks: !options.disable_symlinks,
             preserve_ms_arch_notation: options.preserve_ms_arch_notation,
             use_winsysroot_style: options.use_winsysroot_style,
+            preserve_versions: options.preserve_versions,
             splat_output: output.unwrap_or_else(|| ctx.work_dir.join("splat")),
             copy,
             minimize_output,

src/minimize.rs

@@ -6,6 +6,7 @@ pub struct MinimizeConfig {
     pub include_debug_symbols: bool,
     pub enable_symlinks: bool,
     pub use_winsysroot_style: bool,
+    pub preserve_versions: bool,
     pub preserve_ms_arch_notation: bool,
     pub splat_output: PathBuf,
     pub copy: bool,

src/splat.rs

@@ -32,6 +32,7 @@ pub struct SplatConfig {
     pub enable_symlinks: bool,
     pub preserve_ms_arch_notation: bool,
     pub use_winsysroot_style: bool,
+    pub preserve_versions: bool,
     pub output: PathBuf,
     pub map: Option<PathBuf>,
     pub copy: bool,
@@ -79,6 +80,9 @@ pub(crate) fn prep_splat(
     ctx: std::sync::Arc<Ctx>,
     root: &Path,
     winroot: Option<&str>,
+    sdk_version: Option<&str>,
+    vcrd_version: Option<&str>,
+    preserve_versions: bool,
 ) -> Result<SplatRoots, Error> {
     // Ensure we create the path first, you can't canonicalize a non-existant path
     if !root.exists() {
@@ -107,14 +111,40 @@ pub(crate) fn prep_splat(
             .with_context(|| format!("unable to delete existing CRT directory {crt_root}"))?;
     }
 
-    if sdk_root.exists() {
-        std::fs::remove_dir_all(&sdk_root)
-            .with_context(|| format!("unable to delete existing SDK directory {sdk_root}"))?;
-    }
+    // In winsysroot style, the CRT root is already version scoped, but the SDK
+    // and VCR roots contain every version that has ever been splatted, so when
+    // the user wants to preserve previously installed versions we only remove
+    // the directories belonging to the version being (re)installed
+    if preserve_versions && winroot.is_some() {
+        if let Some(sdk_version) = sdk_version {
+            for subdir in ["Include", "Lib"] {
+                let versioned = sdk_root.join(subdir).join(sdk_version);
+                if versioned.exists() {
+                    std::fs::remove_dir_all(&versioned).with_context(|| {
+                        format!("unable to delete existing SDK {subdir} directory {versioned}")
+                    })?;
+                }
+            }
+        }
+
+        if let Some(vcrd_version) = vcrd_version {
+            let versioned = vcrd_root.join(vcrd_version);
+            if versioned.exists() {
+                std::fs::remove_dir_all(&versioned).with_context(|| {
+                    format!("unable to delete existing VCR directory {versioned}")
+                })?;
+            }
+        }
+    } else {
+        if sdk_root.exists() {
+            std::fs::remove_dir_all(&sdk_root)
+                .with_context(|| format!("unable to delete existing SDK directory {sdk_root}"))?;
+        }
 
-    if vcrd_root.exists() {
-        std::fs::remove_dir_all(&vcrd_root)
-            .with_context(|| format!("unable to delete existing VCR directory {vcrd_root}"))?;
+        if vcrd_root.exists() {
+            std::fs::remove_dir_all(&vcrd_root)
+                .with_context(|| format!("unable to delete existing VCR directory {vcrd_root}"))?;
+        }
     }
 
     std::fs::create_dir_all(&crt_root)

tests/compiles.rs

@@ -61,6 +61,7 @@ fn verify_compiles() {
             enable_symlinks: matches!(style, Style::Default),
             preserve_ms_arch_notation: matches!(style, Style::WinSysRoot),
             use_winsysroot_style: matches!(style, Style::WinSysRoot),
+            preserve_versions: false,
             map: None,
             copy: true,
             output: output_dir.clone(),
@@ -218,6 +219,7 @@ fn verify_compiles_minimized() {
         enable_symlinks: true,
         preserve_ms_arch_notation: false,
         use_winsysroot_style: false,
+        preserve_versions: false,
         map: map_path.clone(),
         copy: true,
         splat_output: output_dir.clone(),
@@ -336,6 +338,7 @@ fn verify_aarch64_compiles() {
             enable_symlinks: matches!(style, Style::Default),
             preserve_ms_arch_notation: matches!(style, Style::WinSysRoot),
             use_winsysroot_style: matches!(style, Style::WinSysRoot),
+            preserve_versions: false,
             map: None,
             copy: true,
             output: output_dir.clone(),

tests/deterministic.rs

@@ -42,6 +42,7 @@ fn verify_deterministic() {
         enable_symlinks: true,
         preserve_ms_arch_notation: false,
         use_winsysroot_style: false,
+        preserve_versions: false,
         map: None,
         copy: true,
         output: output_dir.clone(),

tests/snapshots/xwin-minimize.snap

@@ -47,6 +47,11 @@ Options:
           --preserve-ms-arch-notation and --disable-symlinks for use with
           clang-cl on Windows
 
+      --preserve-versions
+          Keep other CRT/SDK/VCR versions already present in the splat output;
+          only the version being installed is removed first (requires
+          --use-winsysroot-style)
+
       --map <MAP>
           The path of the filter file that is generated. Defaults to
           ./.xwin-cache/xwin-map.toml

tests/snapshots/xwin-splat.snap

@@ -41,6 +41,11 @@ Options:
           --preserve-ms-arch-notation and --disable-symlinks for use with
           clang-cl on Windows
 
+      --preserve-versions
+          Keep other CRT/SDK/VCR versions already present in the splat output;
+          only the version being installed is removed first (requires
+          --use-winsysroot-style)
+
       --output <OUTPUT>
           The root output directory. Defaults to `./.xwin-cache/splat` if not
           specified