fix(linker): don't symlink on Windows (#1253)

1) FAT (FAT32, exFAT, etc.) file systems doesn't support symlinks.
2) You need administrator access in order to create symlinks.

This was working for me locally because I'm running a NTFS fs with
"Developer Mode" enabled in Windows 10, which bypasses administrator
requirement for mklink.

Instead we uv_fs_rename() links. This should effectively be the same,
but will require special handling down the road if/when for example
multiple package versions can be installed at the same time. When
unlinking a package the renamed files should me moved back into the
package installation directory, instead of simply being unlinked (i.e.
removed).

Closes #1251.

1 files changed, 54 insertions, 2 deletions

diff --git a/tests/mason-core/installer/linker_spec.lua b/tests/mason-core/installer/linker_spec.lua
index ac66b212..0a2b62ab 100644
--- a/tests/mason-core/installer/linker_spec.lua
+++ b/tests/mason-core/installer/linker_spec.lua
@@ -21,7 +21,7 @@ describe("linker", function()
     local platform
 
     before_each(function()
-        package.loaded["mason-core.installer.platform"] = nil
+        package.loaded["mason-core.platform"] = nil
         package.loaded["mason-core.installer.linker"] = nil
         platform = require "mason-core.platform"
         linker = require "mason-core.installer.linker"
@@ -131,7 +131,10 @@ describe("linker", function()
             local ctx = InstallContextGenerator(handle)
             ctx.links.share["nested/path/share-file"] = path.concat { "nested", "path", "to", "share-file" }
             ctx.links.share["share-file"] = "share-file"
-            assert.is_true(linker.link(ctx):is_success())
+
+            local result = linker.link(ctx)
+
+            assert.is_true(result:is_success())
 
             assert.spy(fs.async.write_file).was_called(0)
             assert.spy(fs.async.symlink).was_called(2)
@@ -148,4 +151,53 @@ describe("linker", function()
             assert.spy(fs.async.mkdirp).was_called_with(path.share_prefix "nested/path")
         end)
     )
+
+    it("should rename share files on Windows", function()
+        platform.is.darwin = false
+        platform.is.mac = false
+        platform.is.linux = false
+        platform.is.unix = false
+        platform.is.win = true
+
+        local dummy = registry.get_package "dummy"
+        stub(fs.async, "mkdirp")
+        stub(fs.async, "dir_exists")
+        stub(fs.async, "file_exists")
+        stub(fs.async, "rename")
+
+        -- mock non-existent dest files
+        fs.async.file_exists.on_call_with(path.share_prefix "share-file").returns(false)
+        fs.async.file_exists.on_call_with(path.share_prefix(path.concat { "nested", "share-file" })).returns(false)
+
+        fs.async.dir_exists.on_call_with(path.share_prefix()).returns(false)
+        fs.async.dir_exists.on_call_with(path.share_prefix "nested/path").returns(false)
+
+        -- mock existent source files
+        fs.async.file_exists.on_call_with(path.concat { dummy:get_install_path(), "share-file" }).returns(true)
+        fs.async.file_exists
+            .on_call_with(path.concat { dummy:get_install_path(), "nested", "path", "to", "share-file" })
+            .returns(true)
+
+        local handle = InstallHandleGenerator "dummy"
+        local ctx = InstallContextGenerator(handle)
+        ctx.links.share["nested/path/share-file"] = path.concat { "nested", "path", "to", "share-file" }
+        ctx.links.share["share-file"] = "share-file"
+
+        local result = linker.link(ctx)
+
+        assert.is_true(result:is_success())
+
+        assert.spy(fs.async.rename).was_called(2)
+        assert
+            .spy(fs.async.rename)
+            .was_called_with(path.concat { dummy:get_install_path(), "share-file" }, path.share_prefix "share-file")
+        assert.spy(fs.async.rename).was_called_with(
+            path.concat { dummy:get_install_path(), "nested", "path", "to", "share-file" },
+            path.share_prefix "nested/path/share-file"
+        )
+
+        assert.spy(fs.async.mkdirp).was_called(2)
+        assert.spy(fs.async.mkdirp).was_called_with(path.share_prefix())
+        assert.spy(fs.async.mkdirp).was_called_with(path.share_prefix "nested/path")
+    end)
 end)