fix(core): capture snapshots for a Location opened through a symlink (#61546)

packages/core/src/snapshot.ts

@@ -105,10 +105,15 @@ const layer = Layer.effect(
     )
     const repository = repositoryFiber.pipe(Effect.uninterruptible, Effect.flatMap(Fiber.join))
 
+    // The worktree is a real path, so the Location must be one too: a symlinked or junctioned path would fall outside
+    // it, and a path in another letter case would become a pathspec that matches nothing.
     const scope = Effect.fnUntraced(function* (worktree: AbsolutePath) {
-      if (!FSUtil.contains(worktree, location.directory))
+      const directory = yield* fs
+        .realPath(location.directory)
+        .pipe(Effect.mapError((cause) => failure("capture", cause)))
+      if (!FSUtil.contains(worktree, directory))
         return yield* new Error({ operation: "capture", message: "Location is outside the project" })
-      return RelativePath.make(path.relative(worktree, location.directory).replaceAll("\\", "/") || ".")
+      return RelativePath.make(path.relative(worktree, directory).replaceAll("\\", "/") || ".")
     })
 
     const enabled = () => location.vcs?.type === "git" && state.get().enabled

packages/core/test/snapshot.test.ts

@@ -216,6 +216,58 @@ describe("Snapshot", () => {
     ),
   )
 
+  testEffect(Layer.empty).live("captures and restores a Location opened through a symlinked path", () =>
+    withTempDir((tmp) =>
+      Effect.gen(function* () {
+        const project = path.join(tmp.path, "project")
+        const link = path.join(tmp.path, "link")
+        yield* Effect.promise(async () => {
+          await fs.mkdir(path.join(project, "scope"), { recursive: true })
+          await fs.writeFile(path.join(project, "scope", "tracked.txt"), "one\n")
+          await initGit(project)
+          // A junction needs no privilege on Windows; other platforms ignore the type.
+          await fs.symlink(project, link, "junction")
+        })
+        yield* Effect.gen(function* () {
+          const snapshot = yield* Snapshot.Service
+          const before = yield* snapshot.capture()
+          yield* Effect.promise(() => fs.writeFile(path.join(link, "scope", "tracked.txt"), "two\n"))
+          const after = yield* snapshot.capture()
+          expect(before).toBeDefined()
+          expect(after).toBeDefined()
+          if (!before || !after) return
+          expect(yield* snapshot.files({ from: before, to: after })).toEqual([RelativePath.make("scope/tracked.txt")])
+          yield* snapshot.restore({ files: new Map([[RelativePath.make("scope/tracked.txt"), before]]) })
+          expect(yield* read(path.join(project, "scope", "tracked.txt"))).toBe("one\n")
+        }).pipe(Effect.provide(snapshotLayer(tmp.path, path.join(link, "scope"))))
+      }),
+    ),
+  )
+  ;(process.platform === "win32" ? testEffect(Layer.empty).live : testEffect(Layer.empty).live.skip)(
+    "captures a Location opened with different letter case",
+    () =>
+      withTempDir((tmp) =>
+        Effect.gen(function* () {
+          const project = path.join(tmp.path, "project")
+          yield* Effect.promise(async () => {
+            await fs.mkdir(path.join(project, "scope"), { recursive: true })
+            await fs.writeFile(path.join(project, "scope", "tracked.txt"), "one\n")
+            await initGit(project)
+          })
+          yield* Effect.gen(function* () {
+            const snapshot = yield* Snapshot.Service
+            const before = yield* snapshot.capture()
+            yield* Effect.promise(() => fs.writeFile(path.join(project, "scope", "tracked.txt"), "two\n"))
+            const after = yield* snapshot.capture()
+            expect(before).toBeDefined()
+            expect(after).toBeDefined()
+            if (!before || !after) return
+            expect(yield* snapshot.files({ from: before, to: after })).toEqual([RelativePath.make("scope/tracked.txt")])
+          }).pipe(Effect.provide(snapshotLayer(tmp.path, path.join(project, "SCOPE"))))
+        }),
+      ),
+  )
+
   testEffect(Layer.empty).live("restores many files from several trees and removes paths absent from them", () =>
     withTempDir((tmp) =>
       Effect.gen(function* () {