Implement Path.home on Windows

.github/workflows/win.yml

@@ -244,7 +244,7 @@ jobs:
           cl /MT /c src\llvm\ext\llvm_ext.cc -I llvm\include /Fosrc\llvm\ext\llvm_ext.obj
       - name: Link Crystal executable
         run: |
-          Invoke-Expression "cl crystal.obj /Fecrystal-cross src\llvm\ext\llvm_ext.obj $(llvm\bin\llvm-config.exe --libs) libs\pcre.lib libs\gc.lib WS2_32.lib advapi32.lib libcmt.lib dbghelp.lib legacy_stdio_definitions.lib /link /LIBPATH:$(pwd)\libs /STACK:10000000"
+          Invoke-Expression "cl crystal.obj /Fecrystal-cross src\llvm\ext\llvm_ext.obj $(llvm\bin\llvm-config.exe --libs) libs\pcre.lib libs\gc.lib WS2_32.lib advapi32.lib libcmt.lib dbghelp.lib ole32.lib shell32.lib legacy_stdio_definitions.lib /link /LIBPATH:$(pwd)\libs /STACK:10000000"
 
       - name: Re-build Crystal
         run: |

spec/std/file_spec.cr

@@ -558,102 +558,15 @@ describe "File" do
     end
   end
 
-  # TODO: these specs are redundant with path_spec.cr
-  describe "expand_path" do
-    pending_win32 "converts a pathname to an absolute pathname" do
-      File.expand_path("").should eq(base)
-      File.expand_path("a").should eq(File.join([base, "a"]))
-      File.expand_path("a", nil).should eq(File.join([base, "a"]))
-    end
-
-    pending_win32 "converts a pathname to an absolute pathname, Ruby-Talk:18512" do
-      File.expand_path(".a").should eq(File.join([base, ".a"]))
-      File.expand_path("..a").should eq(File.join([base, "..a"]))
-      File.expand_path("a../b").should eq(File.join([base, "a../b"]))
-    end
-
-    pending_win32 "keeps trailing dots on absolute pathname" do
-      File.expand_path("a.").should eq(File.join([base, "a."]))
-      File.expand_path("a..").should eq(File.join([base, "a.."]))
-    end
-
-    pending_win32 "converts a pathname to an absolute pathname, using a complete path" do
-      File.expand_path("", "#{tmpdir}").should eq("#{tmpdir}")
-      File.expand_path("a", "#{tmpdir}").should eq("#{tmpdir}/a")
-      File.expand_path("../a", "#{tmpdir}/xxx").should eq("#{tmpdir}/a")
-      File.expand_path(".", "#{rootdir}").should eq("#{rootdir}")
-    end
-
-    pending_win32 "expands a path with multi-byte characters" do
-      File.expand_path("Ångström").should eq("#{base}/Ångström")
-    end
-
-    pending_win32 "expands /./dir to /dir" do
-      File.expand_path("/./dir").should eq("/dir")
-    end
-
-    pending_win32 "replaces multiple / with a single /" do
-      File.expand_path("////some/path").should eq("/some/path")
-      File.expand_path("/some////path").should eq("/some/path")
-    end
-
-    pending_win32 "expand path with" do
-      File.expand_path("../../bin", "/tmp/x").should eq("/bin")
-      File.expand_path("../../bin", "/tmp").should eq("/bin")
-      File.expand_path("../../bin", "/").should eq("/bin")
-      File.expand_path("../bin", "tmp/x").should eq(File.join([base, "tmp", "bin"]))
-      File.expand_path("../bin", "x/../tmp").should eq(File.join([base, "bin"]))
-    end
-
-    pending_win32 "expand_path for common unix path gives a full path" do
-      File.expand_path("/tmp/").should eq("/tmp/")
-      File.expand_path("/tmp/../../../tmp").should eq("/tmp")
-      File.expand_path("").should eq(base)
-      File.expand_path("./////").should eq(File.join(base, ""))
-      File.expand_path(".").should eq(base)
-      File.expand_path(base).should eq(base)
-    end
-
-    pending_win32 "converts a pathname to an absolute pathname, using ~ (home) as base" do
-      File.expand_path("~/", home: true).should eq(File.join(home, ""))
-      File.expand_path("~/..badfilename", home: true).should eq(File.join(home, "..badfilename"))
-      File.expand_path("..", home: true).should eq("/#{base.split('/')[0...-1].join('/')}".gsub(%r{\A//}, "/"))
-      File.expand_path("~/a", "~/b", home: true).should eq(File.join(home, "a"))
-      File.expand_path("~", home: true).should eq(home)
-      File.expand_path("~", "/tmp/gumby/ddd", home: true).should eq(home)
-      File.expand_path("~/a", "/tmp/gumby/ddd", home: true).should eq(File.join([home, "a"]))
-    end
-
-    pending_win32 "converts a pathname to an absolute pathname, using ~ (home) as base (trailing /)" do
-      prev_home = home
-      begin
-        ENV["HOME"] = File.expand_path(datapath)
-        File.expand_path("~/", home: true).should eq(File.join(home, ""))
-        File.expand_path("~/..badfilename", home: true).should eq(File.join(home, "..badfilename"))
-        File.expand_path("..", home: true).should eq("/#{base.split('/')[0...-1].join('/')}".gsub(%r{\A//}, "/"))
-        File.expand_path("~/a", "~/b", home: true).should eq(File.join(home, "a"))
-        File.expand_path("~", home: true).should eq(home)
-        File.expand_path("~", "/tmp/gumby/ddd", home: true).should eq(home)
-        File.expand_path("~/a", "/tmp/gumby/ddd", home: true).should eq(File.join([home, "a"]))
-      ensure
-        ENV["HOME"] = prev_home
-      end
-    end
-
-    pending_win32 "converts a pathname to an absolute pathname, using ~ (home) as base (HOME=/)" do
-      prev_home = home
-      begin
-        ENV["HOME"] = "/"
-        File.expand_path("~/", home: true).should eq(home)
-        File.expand_path("~/..badfilename", home: true).should eq(File.join(home, "..badfilename"))
-        File.expand_path("..", home: true).should eq("/#{base.split('/')[0...-1].join('/')}".gsub(/\A\/\//, "/"))
-        File.expand_path("~/a", "~/b", home: true).should eq(File.join(home, "a"))
-        File.expand_path("~", home: true).should eq(home)
-        File.expand_path("~", "/tmp/gumby/ddd", home: true).should eq(home)
-        File.expand_path("~/a", "/tmp/gumby/ddd", home: true).should eq(File.join([home, "a"]))
-      ensure
-        ENV["HOME"] = prev_home
-      end
+  # There are more detailled specs for `Path#expand` in path_spec.cr
+  describe ".expand_path" do
+    it "converts a pathname to an absolute pathname" do
+      File.expand_path("a/b").should eq(Path.new("a/b").expand(Dir.current).to_s)
+      File.expand_path("a/b", "c/d").should eq(Path.new("a/b").expand("c/d").to_s)
+      File.expand_path("~/b", home: "c/d").should eq(Path.new("~/b").expand(Dir.current, home: "c/d").to_s)
+      File.expand_path("~/b", "c/d", home: false).should eq(Path.new("~/b").expand("c/d", home: false).to_s)
+
+      File.expand_path(Path.new("a/b")).should eq(Path.new("a/b").expand(Dir.current).to_s)
     end
   end
 

spec/std/path_spec.cr

@@ -1,6 +1,8 @@
 require "spec"
 require "./spec_helper"
+require "../support/env"
 
+private HOME_ENV_KEY = {% if flag?(:win32) %} "USERPROFILE" {% else %} "HOME" {% end %}
 private BASE_POSIX   = "/default/base"
 private BASE_WINDOWS = "\\default\\base"
 private HOME_WINDOWS = "C:\\Users\\Crystal"
@@ -12,15 +14,9 @@ end
 
 private def it_expands_path(path, posix, windows = posix, *, base = nil, env_home = nil, expand_base = false, home = false, file = __FILE__, line = __LINE__)
   assert_paths(path, posix, windows, %((base: "#{base}")), file, line) do |path|
-    prev_home = ENV["HOME"]?
-
-    begin
-      ENV["HOME"] = env_home || (path.windows? ? HOME_WINDOWS : HOME_POSIX)
-
+    with_env({HOME_ENV_KEY => env_home || (path.windows? ? HOME_WINDOWS : HOME_POSIX)}) do
       base_arg = base || (path.windows? ? BASE_WINDOWS : BASE_POSIX)
       path.expand(base_arg.not_nil!, expand_base: !!expand_base, home: home)
-    ensure
-      ENV["HOME"] = prev_home
     end
   end
 end
@@ -584,7 +580,7 @@ describe Path do
     describe "converts a pathname to an absolute pathname" do
       it_expands_path("", BASE_POSIX, BASE_WINDOWS)
       it_expands_path("a", {BASE_POSIX, "a"}, {BASE_WINDOWS, "a"})
-      it_expands_path("a", {BASE_POSIX, "a"}, {BASE_WINDOWS, "a"})
+      it_expands_path("a", {BASE_POSIX, "a"}, {BASE_WINDOWS, "a"}, base: nil)
     end
 
     describe "converts a pathname to an absolute pathname, Ruby-Talk:18512" do
@@ -625,7 +621,7 @@ describe Path do
       it_expands_path("/some////path", "/some/path", "\\some\\path")
     end
 
-    describe "expand path with" do
+    describe "expand path with .." do
       it_expands_path("../../bin", "/bin", "\\bin", base: "/tmp/x")
       it_expands_path("../../bin", "/bin", "\\bin", base: "/tmp")
       it_expands_path("../../bin", "/bin", "\\bin", base: "/")
@@ -889,4 +885,21 @@ describe Path do
     assert_paths_raw("foo.txt./", "foo.txt.", &.stem)
     assert_paths_raw("foo..txt/", "foo.", &.stem)
   end
+
+  describe ".home" do
+    it "uses home from environment variable if set" do
+      with_env({HOME_ENV_KEY => "foo/bar"}) do
+        Path.home.should eq(Path.new("foo/bar"))
+      end
+    end
+
+    # TODO: check that this is the home of the current user
+    {% if flag?(:win32) %}
+      it "doesn't raise if environment variable is missing" do
+        with_env({HOME_ENV_KEY => nil}) do
+          Path.home
+        end
+      end
+    {% end %}
+  end
 end

spec/support/env.cr

@@ -1,4 +1,4 @@
-def with_env(**values)
+def with_env(values : Hash)
   old_values = {} of String => String?
   begin
     values.each do |key, value|
@@ -14,3 +14,7 @@ def with_env(**values)
     end
   end
 end
+
+def with_env(**values)
+  with_env(values.to_h) { yield }
+end

src/crystal/system/path.cr

@@ -0,0 +1,12 @@
+module Crystal::System::Path
+  # Returns the path of the home directory of the current user.
+  # def self.home : String
+end
+
+{% if flag?(:unix) %}
+  require "./unix/path"
+{% elsif flag?(:win32) %}
+  require "./win32/path"
+{% else %}
+  {% raise "No Crystal::System::Path implementation available" %}
+{% end %}

src/crystal/system/unix/path.cr

@@ -0,0 +1,5 @@
+module Crystal::System::Path
+  def self.home : String
+    ENV["HOME"]
+  end
+end

src/crystal/system/win32/path.cr

@@ -0,0 +1,17 @@
+require "c/combaseapi"
+require "c/knownfolders"
+require "c/shlobj_core"
+
+module Crystal::System::Path
+  def self.home : String
+    if home_path = ENV["USERPROFILE"]?
+      home_path
+    elsif LibC.SHGetKnownFolderPath(pointerof(LibC::FOLDERID_Profile), 0, nil, out path_ptr) == 0
+      home_path, _ = String.from_utf16(path_ptr)
+      LibC.CoTaskMemFree(path_ptr)
+      home_path
+    else
+      raise RuntimeError.from_winerror("SHGetKnownFolderPath")
+    end
+  end
+end

src/lib_c/x86_64-windows-msvc/c/combaseapi.cr

@@ -0,0 +1,4 @@
+@[Link("ole32")]
+lib LibC
+  fun CoTaskMemFree(pv : Void*)
+end

src/lib_c/x86_64-windows-msvc/c/knownfolders.cr

@@ -0,0 +1,5 @@
+require "c/guiddef"
+
+lib LibC
+  FOLDERID_Profile = GUID.new(0x5e6c858f, 0x0e22, 0x4760, UInt8.static_array(0x9a, 0xfe, 0xea, 0x33, 0x17, 0xb6, 0x71, 0x73))
+end

src/lib_c/x86_64-windows-msvc/c/shlobj_core.cr

@@ -0,0 +1,6 @@
+require "c/guiddef"
+
+@[Link("shell32")]
+lib LibC
+  fun SHGetKnownFolderPath(rfid : GUID*, dwFlags : DWORD, hToken : HANDLE, ppszPath : LPWSTR*) : DWORD
+end

src/path.cr

@@ -1,3 +1,5 @@
+require "crystal/system/path"
+
 # A `Path` represents a filesystem path and allows path-handling operations
 # such as querying its components as well as semantic manipulations.
 #
@@ -1359,6 +1361,6 @@ struct Path
 
   # Returns the path of the home directory of the current user.
   def self.home : Path
-    new ENV["HOME"]
+    new(Crystal::System::Path.home)
   end
 end