Add macOS support for Swiftly toolchain management

Author: roulpriya

CHANGELOG.md

@@ -15,6 +15,7 @@
 - Ensure document symbols are provided for folders in multi-root workspaces ([#1668](https://github.com/swiftlang/vscode-swift/pull/1668))
 
 ## 2.6.1 - 2025-06-27
+- Add macOS support for Swiftly toolchain management
 
 ### Fixed
 

src/toolchain/toolchain.ts

@@ -254,9 +254,8 @@ export class SwiftToolchain {
      * @returns an array of toolchain paths
      */
     public static async getSwiftlyToolchainInstalls(): Promise<string[]> {
-        // Swiftly is only available on Linux right now
-        // TODO: Add support for macOS
-        if (process.platform !== "linux") {
+        // Swiftly is available on Linux and macOS
+        if (process.platform !== "linux" && process.platform !== "darwin") {
             return [];
         }
         try {

src/ui/ToolchainSelection.ts

@@ -223,11 +223,12 @@ async function getQuickPickItems(
     }
     // Various actions that the user can perform (e.g. to install new toolchains)
     const actionItems: ActionItem[] = [];
-    if (process.platform === "linux") {
+    if (process.platform === "linux" || process.platform === "darwin") {
+        const platformName = process.platform === "linux" ? "Linux" : "macOS";
         actionItems.push({
             type: "action",
             label: "$(swift-icon) Install Swiftly for toolchain management...",
-            detail: "Install https://swiftlang.github.io/swiftly to manage your toolchains on Linux",
+            detail: `Install https://swiftlang.github.io/swiftly to manage your toolchains on ${platformName}`,
             run: installSwiftly,
         });
     }

test/unit-tests/toolchain/toolchain.test.ts

@@ -296,4 +296,104 @@ suite("SwiftToolchain Unit Test Suite", () => {
             await expect(SwiftToolchain.findXcodeInstalls()).to.eventually.be.empty;
         });
     });
+
+    suite("getSwiftlyToolchainInstalls()", () => {
+        const mockedEnv = mockGlobalValue(process, "env");
+
+        test("returns installed toolchains on Linux", async () => {
+            mockedPlatform.setValue("linux");
+            const mockHomeDir = "/home/user/.swiftly";
+            mockedEnv.setValue({ SWIFTLY_HOME_DIR: mockHomeDir });
+
+            mockFS({
+                [path.join(mockHomeDir, "config.json")]: JSON.stringify({
+                    installedToolchains: ["swift-5.9.0", "swift-6.0.0"],
+                }),
+            });
+
+            const toolchains = await SwiftToolchain.getSwiftlyToolchainInstalls();
+            expect(toolchains).to.deep.equal([
+                path.join(mockHomeDir, "toolchains", "swift-5.9.0"),
+                path.join(mockHomeDir, "toolchains", "swift-6.0.0"),
+            ]);
+        });
+
+        test("returns installed toolchains on macOS", async () => {
+            mockedPlatform.setValue("darwin");
+            const mockHomeDir = "/Users/user/.swiftly";
+            mockedEnv.setValue({ SWIFTLY_HOME_DIR: mockHomeDir });
+
+            mockFS({
+                [path.join(mockHomeDir, "config.json")]: JSON.stringify({
+                    installedToolchains: ["swift-5.9.0", "swift-6.0.0"],
+                }),
+            });
+
+            const toolchains = await SwiftToolchain.getSwiftlyToolchainInstalls();
+            expect(toolchains).to.deep.equal([
+                path.join(mockHomeDir, "toolchains", "swift-5.9.0"),
+                path.join(mockHomeDir, "toolchains", "swift-6.0.0"),
+            ]);
+        });
+
+        test("returns empty array when SWIFTLY_HOME_DIR is not set", async () => {
+            mockedPlatform.setValue("linux");
+            mockedEnv.setValue({});
+
+            const toolchains = await SwiftToolchain.getSwiftlyToolchainInstalls();
+            expect(toolchains).to.be.empty;
+        });
+
+        test("returns empty array when config file does not exist", async () => {
+            mockedPlatform.setValue("linux");
+            const mockHomeDir = "/home/user/.swiftly";
+            mockedEnv.setValue({ SWIFTLY_HOME_DIR: mockHomeDir });
+
+            mockFS({});
+
+            await expect(SwiftToolchain.getSwiftlyToolchainInstalls()).to.be.rejectedWith(
+                "Failed to retrieve Swiftly installations from disk."
+            );
+        });
+
+        test("returns empty array when config has no installedToolchains", async () => {
+            mockedPlatform.setValue("linux");
+            const mockHomeDir = "/home/user/.swiftly";
+            mockedEnv.setValue({ SWIFTLY_HOME_DIR: mockHomeDir });
+
+            mockFS({
+                [path.join(mockHomeDir, "config.json")]: JSON.stringify({
+                    someOtherProperty: "value",
+                }),
+            });
+
+            const toolchains = await SwiftToolchain.getSwiftlyToolchainInstalls();
+            expect(toolchains).to.be.empty;
+        });
+
+        test("returns empty array on Windows", async () => {
+            mockedPlatform.setValue("win32");
+            const toolchains = await SwiftToolchain.getSwiftlyToolchainInstalls();
+            expect(toolchains).to.be.empty;
+        });
+
+        test("filters out non-string toolchain entries", async () => {
+            mockedPlatform.setValue("linux");
+            const mockHomeDir = "/home/user/.swiftly";
+            mockedEnv.setValue({ SWIFTLY_HOME_DIR: mockHomeDir });
+
+            mockFS({
+                [path.join(mockHomeDir, "config.json")]: JSON.stringify({
+                    installedToolchains: ["swift-5.9.0", null, "swift-6.0.0", 123, "swift-6.1.0"],
+                }),
+            });
+
+            const toolchains = await SwiftToolchain.getSwiftlyToolchainInstalls();
+            expect(toolchains).to.deep.equal([
+                path.join(mockHomeDir, "toolchains", "swift-5.9.0"),
+                path.join(mockHomeDir, "toolchains", "swift-6.0.0"),
+                path.join(mockHomeDir, "toolchains", "swift-6.1.0"),
+            ]);
+        });
+    });
 });