fossil: don't pass --with-tcl unless CLT available

This seems to resolve the problem in Homebrew/homebrew#42493, but since there's no explicit
`--without-tcl` option, not 110% sure.

Closes Homebrew/homebrew#42493.

Closes Homebrew/homebrew#43895.

Signed-off-by: Dominyk Tiller <dominyktiller@gmail.com>

Formula/fossil.rb

@@ -1,10 +1,11 @@
 class Fossil < Formula
   desc "Distributed software configuration management"
   homepage "https://www.fossil-scm.org/"
-  head "https://www.fossil-scm.org/", :using => :fossil
   url "https://www.fossil-scm.org/download/fossil-src-1.33.tar.gz"
   sha256 "6295c48289456f09e86099988058a12148dbe0051b72d413b4dff7216d6a7f3e"
 
+  head "https://www.fossil-scm.org/", :using => :fossil
+
   bottle do
     cellar :any
     sha256 "93c2998a284d05cdde365f968aacfcb05e6ce746a90e767de85c4e8a98084b4f" => :yosemite
@@ -16,11 +17,23 @@ class Fossil < Formula
   option "without-tcl", "Build without the tcl-th1 command bridge"
 
   depends_on "openssl"
+  depends_on :osxfuse => :optional
 
   def install
     args = []
     args << "--json" if build.with? "json"
-    args << "--with-tcl" if build.with? "tcl"
+
+    if MacOS::CLT.installed? && build.with?("tcl")
+      args << "--with-tcl"
+    else
+      args << "--with-tcl-stubs"
+    end
+
+    if build.with? "osxfuse"
+      ENV.prepend "CFLAGS", "-I#{HOMEBREW_PREFIX}/include/osxfuse"
+    else
+      args << "--disable-fusefs"
+    end
 
     system "./configure", *args
     system "make"