Support finding Visual Studio instances using vswhere.exe (#597)

* Use SetupInstance COM object in single place only

* Implement searching for VS instances using vswhere

* Respect target arch when using vswhere

* Only use the latest VS version found by vswhere

* Rename vswhere.rs to vs_instances.rs

* Add a check if vswhere.exe exists

* Use static string slice as an error

* Rename tests, add a test for insufficient output

* Use explicit type identifier for compatibility

* WORKAROUND: update Rustup during Test run

Author: Alovchin91

.github/workflows/main.yml

@@ -61,6 +61,10 @@ jobs:
             target: x86_64-pc-windows-msvc
     steps:
     - uses: actions/checkout@master
+    - name: Update Rustup (temporary workaround)
+      run: rustup self update
+      shell: bash
+      if: startsWith(matrix.os, 'windows')
     - name: Install Rust (rustup)
       run: rustup update ${{ matrix.rust }} --no-self-update && rustup default ${{ matrix.rust }}
       shell: bash

src/lib.rs

@@ -78,6 +78,8 @@ mod winapi;
 mod com;
 #[cfg(windows)]
 mod setup_config;
+#[cfg(windows)]
+mod vs_instances;
 
 pub mod windows_registry;
 

src/vs_instances.rs

@@ -0,0 +1,199 @@
+use std::borrow::Cow;
+use std::collections::HashMap;
+use std::convert::TryFrom;
+use std::io::BufRead;
+use std::path::PathBuf;
+
+use crate::setup_config::{EnumSetupInstances, SetupInstance};
+
+pub enum VsInstance {
+    Com(SetupInstance),
+    Vswhere(VswhereInstance),
+}
+
+impl VsInstance {
+    pub fn installation_name(&self) -> Option<Cow<str>> {
+        match self {
+            VsInstance::Com(s) => s
+                .installation_name()
+                .ok()
+                .and_then(|s| s.into_string().ok())
+                .map(Cow::from),
+            VsInstance::Vswhere(v) => v.map.get("installationName").map(Cow::from),
+        }
+    }
+
+    pub fn installation_path(&self) -> Option<PathBuf> {
+        match self {
+            VsInstance::Com(s) => s.installation_path().ok().map(PathBuf::from),
+            VsInstance::Vswhere(v) => v.map.get("installationPath").map(PathBuf::from),
+        }
+    }
+
+    pub fn installation_version(&self) -> Option<Cow<str>> {
+        match self {
+            VsInstance::Com(s) => s
+                .installation_version()
+                .ok()
+                .and_then(|s| s.into_string().ok())
+                .map(Cow::from),
+            VsInstance::Vswhere(v) => v.map.get("installationVersion").map(Cow::from),
+        }
+    }
+}
+
+pub enum VsInstances {
+    ComBased(EnumSetupInstances),
+    VswhereBased(VswhereInstance),
+}
+
+impl IntoIterator for VsInstances {
+    type Item = VsInstance;
+    #[allow(bare_trait_objects)]
+    type IntoIter = Box<Iterator<Item = Self::Item>>;
+
+    fn into_iter(self) -> Self::IntoIter {
+        match self {
+            VsInstances::ComBased(e) => {
+                Box::new(e.into_iter().filter_map(Result::ok).map(VsInstance::Com))
+            }
+            VsInstances::VswhereBased(v) => Box::new(std::iter::once(VsInstance::Vswhere(v))),
+        }
+    }
+}
+
+#[derive(Debug)]
+pub struct VswhereInstance {
+    map: HashMap<String, String>,
+}
+
+impl TryFrom<&Vec<u8>> for VswhereInstance {
+    type Error = &'static str;
+
+    fn try_from(output: &Vec<u8>) -> Result<Self, Self::Error> {
+        let map: HashMap<_, _> = output
+            .lines()
+            .filter_map(Result::ok)
+            .filter_map(|s| {
+                let mut splitn = s.splitn(2, ": ");
+                Some((splitn.next()?.to_owned(), splitn.next()?.to_owned()))
+            })
+            .collect();
+
+        if !map.contains_key("installationName")
+            || !map.contains_key("installationPath")
+            || !map.contains_key("installationVersion")
+        {
+            return Err("required properties not found");
+        }
+
+        Ok(Self { map })
+    }
+}
+
+#[cfg(test)]
+mod tests_ {
+    use std::borrow::Cow;
+    use std::convert::TryFrom;
+    use std::path::PathBuf;
+
+    #[test]
+    fn it_parses_vswhere_output_correctly() {
+        let output = br"instanceId: 58104422
+installDate: 21/02/2021 21:50:33
+installationName: VisualStudio/16.9.2+31112.23
+installationPath: C:\Program Files (x86)\Microsoft Visual Studio\2019\BuildTools
+installationVersion: 16.9.31112.23
+productId: Microsoft.VisualStudio.Product.BuildTools
+productPath: C:\Program Files (x86)\Microsoft Visual Studio\2019\BuildTools\Common7\Tools\LaunchDevCmd.bat
+state: 4294967295
+isComplete: 1
+isLaunchable: 1
+isPrerelease: 0
+isRebootRequired: 0
+displayName: Visual Studio Build Tools 2019
+description: The Visual Studio Build Tools allows you to build native and managed MSBuild-based applications without requiring the Visual Studio IDE. There are options to install the Visual C++ compilers and libraries, MFC, ATL, and C++/CLI support.
+channelId: VisualStudio.16.Release
+channelUri: https://aka.ms/vs/16/release/channel
+enginePath: C:\Program Files (x86)\Microsoft Visual Studio\Installer\resources\app\ServiceHub\Services\Microsoft.VisualStudio.Setup.Service
+releaseNotes: https://docs.microsoft.com/en-us/visualstudio/releases/2019/release-notes-v16.9#16.9.2
+thirdPartyNotices: https://go.microsoft.com/fwlink/?LinkId=660909
+updateDate: 2021-03-17T21:16:46.5963702Z
+catalog_buildBranch: d16.9
+catalog_buildVersion: 16.9.31112.23
+catalog_id: VisualStudio/16.9.2+31112.23
+catalog_localBuild: build-lab
+catalog_manifestName: VisualStudio
+catalog_manifestType: installer
+catalog_productDisplayVersion: 16.9.2
+catalog_productLine: Dev16
+catalog_productLineVersion: 2019
+catalog_productMilestone: RTW
+catalog_productMilestoneIsPreRelease: False
+catalog_productName: Visual Studio
+catalog_productPatchVersion: 2
+catalog_productPreReleaseMilestoneSuffix: 1.0
+catalog_productSemanticVersion: 16.9.2+31112.23
+catalog_requiredEngineVersion: 2.9.3365.38425
+properties_campaignId: 156063665.1613940062
+properties_channelManifestId: VisualStudio.16.Release/16.9.2+31112.23
+properties_nickname: 
+properties_setupEngineFilePath: C:\Program Files (x86)\Microsoft Visual Studio\Installer\vs_installershell.exe
+"
+        .to_vec();
+
+        let vswhere_instance = super::VswhereInstance::try_from(&output);
+        assert!(vswhere_instance.is_ok());
+
+        let vs_instance = super::VsInstance::Vswhere(vswhere_instance.unwrap());
+        assert_eq!(
+            vs_instance.installation_name(),
+            Some(Cow::from("VisualStudio/16.9.2+31112.23"))
+        );
+        assert_eq!(
+            vs_instance.installation_path(),
+            Some(PathBuf::from(
+                r"C:\Program Files (x86)\Microsoft Visual Studio\2019\BuildTools"
+            ))
+        );
+        assert_eq!(
+            vs_instance.installation_version(),
+            Some(Cow::from("16.9.31112.23"))
+        );
+    }
+
+    #[test]
+    fn it_returns_an_error_for_empty_output() {
+        let output = b"".to_vec();
+
+        let vswhere_instance = super::VswhereInstance::try_from(&output);
+
+        assert!(vswhere_instance.is_err());
+    }
+
+    #[test]
+    fn it_returns_an_error_for_output_consisting_of_empty_lines() {
+        let output = br"
+
+"
+        .to_vec();
+
+        let vswhere_instance = super::VswhereInstance::try_from(&output);
+
+        assert!(vswhere_instance.is_err());
+    }
+
+    #[test]
+    fn it_returns_an_error_for_output_without_required_properties() {
+        let output = br"instanceId: 58104422
+installDate: 21/02/2021 21:50:33
+productId: Microsoft.VisualStudio.Product.BuildTools
+productPath: C:\Program Files (x86)\Microsoft Visual Studio\2019\BuildTools\Common7\Tools\LaunchDevCmd.bat
+"
+        .to_vec();
+
+        let vswhere_instance = super::VswhereInstance::try_from(&output);
+
+        assert!(vswhere_instance.is_err());
+    }
+}