Rename test files so that test discovery works again

These files were renamed from os_windows_test.go to os_test_windows.go (etc.) in
95b2e9540a. Since then, the tests have no longer run, since go only looks for
tests in files ending with "test.go".

It isn't important that the file name ends with "_windows.go", since there are
already build constrains in the files themselves.

pkg/commands/oscommands/os_windows_test.go

@@ -0,0 +1,78 @@
+//go:build windows
+// +build windows
+
+package oscommands
+
+import (
+	"testing"
+
+	"github.com/go-errors/errors"
+	"github.com/stretchr/testify/assert"
+)
+
+// handling this in a separate file because str.ToArgv has different behaviour if we're on windows
+
+func TestOSCommandOpenFileWindows(t *testing.T) {
+	type scenario struct {
+		filename string
+		runner   *FakeCmdObjRunner
+		test     func(error)
+	}
+
+	scenarios := []scenario{
+		{
+			filename: "test",
+			runner: NewFakeRunner(t).
+				ExpectArgs([]string{"cmd", "/c", "start", "", "test"}, "", errors.New("error")),
+			test: func(err error) {
+				assert.Error(t, err)
+			},
+		},
+		{
+			filename: "test",
+			runner: NewFakeRunner(t).
+				ExpectArgs([]string{"cmd", "/c", "start", "", "test"}, "", nil),
+			test: func(err error) {
+				assert.NoError(t, err)
+			},
+		},
+		{
+			filename: "filename with spaces",
+			runner: NewFakeRunner(t).
+				ExpectArgs([]string{"cmd", "/c", "start", "", "filename with spaces"}, "", nil),
+			test: func(err error) {
+				assert.NoError(t, err)
+			},
+		},
+		{
+			filename: "let's_test_with_single_quote",
+			runner: NewFakeRunner(t).
+				ExpectArgs([]string{"cmd", "/c", "start", "", "let's_test_with_single_quote"}, "", nil),
+			test: func(err error) {
+				assert.NoError(t, err)
+			},
+		},
+		{
+			filename: "$USER.txt",
+			runner: NewFakeRunner(t).
+				ExpectArgs([]string{"cmd", "/c", "start", "", "$USER.txt"}, "", nil),
+			test: func(err error) {
+				assert.NoError(t, err)
+			},
+		},
+	}
+
+	for _, s := range scenarios {
+		oSCmd := NewDummyOSCommandWithRunner(s.runner)
+		platform := &Platform{
+			OS:       "windows",
+			Shell:    "cmd",
+			ShellArg: "/c",
+		}
+		oSCmd.Platform = platform
+		oSCmd.Cmd.platform = platform
+		oSCmd.UserConfig.OS.OpenCommand = `start "" {{filename}}`
+
+		s.test(oSCmd.OpenFile(s.filename))
+	}
+}