vcxproj: unclash project directories with build outputs

It already caused problems with the test suite that the directory
containing `git.vcxproj` is called the same as the Git executable
without its file extension: `./git` is ambiguous, it could refer both to
the directory `git/` as well as to `git.exe`.

Now there is one more problem: when our GitHub workflow runs on the
`vs/master` branch, it fails in all but the Windows builds, as they want
to write the file `git` but there is already a directory in the way.

Let's just go ahead and append `.proj` to all of those directories, e.g.
`git.proj/` instead of `git/`.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>

config.mak.uname

@@ -767,7 +767,7 @@ vcxproj:
 
 	# Make .vcxproj files and add them
 	perl contrib/buildsystems/generate -g Vcxproj
-	git add -f git.sln {*,*/lib,t/helper/*}/*.vcxproj
+	git add -f git.sln {*,*/lib.proj,t/helper/*}/*.vcxproj
 
 	# Generate the LinkOrCopyBuiltins.targets and LinkOrCopyRemoteHttp.targets file
 	(echo '<Project xmlns="http://schemas.microsoft.com/developer/msbuild/2003">' && \
@@ -777,16 +777,16 @@ vcxproj:
 	   echo '    <Copy SourceFiles="$$(OutDir)\git.exe" DestinationFiles="$$(OutDir)\'"$$name"'" SkipUnchangedFiles="true" UseHardlinksIfPossible="true" />'; \
 	 done && \
 	 echo '  </Target>' && \
-	 echo '</Project>') >git/LinkOrCopyBuiltins.targets
+	 echo '</Project>') >git.proj/LinkOrCopyBuiltins.targets
 	(echo '<Project xmlns="http://schemas.microsoft.com/developer/msbuild/2003">' && \
 	 echo '  <Target Name="CopyBuiltins_AfterBuild" AfterTargets="AfterBuild">' && \
 	 for name in $(REMOTE_CURL_ALIASES); \
 	 do \
 	   echo '    <Copy SourceFiles="$$(OutDir)\'"$(REMOTE_CURL_PRIMARY)"'" DestinationFiles="$$(OutDir)\'"$$name"'" SkipUnchangedFiles="true" UseHardlinksIfPossible="true" />'; \
 	 done && \
 	 echo '  </Target>' && \
-	 echo '</Project>') >git-remote-http/LinkOrCopyRemoteHttp.targets
-	git add -f git/LinkOrCopyBuiltins.targets git-remote-http/LinkOrCopyRemoteHttp.targets
+	 echo '</Project>') >git-remote-http.proj/LinkOrCopyRemoteHttp.targets
+	git add -f git.proj/LinkOrCopyBuiltins.targets git-remote-http.proj/LinkOrCopyRemoteHttp.targets
 
 	# Add generated headers
 	$(MAKE) MSVC=1 SKIP_VCPKG=1 prefix=/mingw64 $(GENERATED_H)

contrib/buildsystems/Generators/Vcxproj.pm

@@ -58,8 +58,8 @@ sub createProject {
     my $uuid = generate_guid($name);
     $$build_structure{"$prefix${target}_GUID"} = $uuid;
     my $vcxproj = $target;
-    $vcxproj =~ s/(.*\/)?(.*)/$&\/$2.vcxproj/;
-    $vcxproj =~ s/([^\/]*)(\/lib)\/(lib.vcxproj)/$1$2\/$1_$3/;
+    $vcxproj =~ s/(.*\/)?(.*)/$&.proj\/$2.vcxproj/;
+    $vcxproj =~ s/([^\/]*)(\/lib\.proj)\/(lib.vcxproj)/$1$2\/$1_$3/;
     $$build_structure{"$prefix${target}_VCXPROJ"} = $vcxproj;
 
     my @srcs = sort(map("$rel_dir\\$_", @{$$build_structure{"$prefix${name}_SOURCES"}}));
@@ -89,7 +89,9 @@ sub createProject {
     $defines =~ s/>/>/g;
     $defines =~ s/\'//g;
 
-    die "Could not create the directory $target for $label project!\n" unless (-d "$target" || mkdir "$target");
+    my $dir = $vcxproj;
+    $dir =~ s/\/[^\/]*$//;
+    die "Could not create the directory $dir for $label project!\n" unless (-d "$dir" || mkdir "$dir");
 
     open F, ">$vcxproj" or die "Could not open $vcxproj for writing!\n";
     binmode F, ":crlf :utf8";
@@ -237,7 +239,7 @@ EOM
 
       print F << "EOM";
   <ItemGroup>
-    <ProjectReference Include="$cdup\\libgit\\libgit.vcxproj">
+    <ProjectReference Include="$cdup\\libgit.proj\\libgit.vcxproj">
       <Project>$uuid_libgit</Project>
       <ReferenceOutputAssembly>false</ReferenceOutputAssembly>
     </ProjectReference>
@@ -252,7 +254,7 @@ EOM
       }
       if (!($name =~ 'xdiff')) {
         print F << "EOM";
-    <ProjectReference Include="$cdup\\xdiff\\lib\\xdiff_lib.vcxproj">
+    <ProjectReference Include="$cdup\\xdiff\\lib.proj\\xdiff_lib.vcxproj">
       <Project>$uuid_xdiff_lib</Project>
       <ReferenceOutputAssembly>false</ReferenceOutputAssembly>
     </ProjectReference>
@@ -261,7 +263,7 @@ EOM
       if ($name =~ /(test-(line-buffer|svn-fe)|^git-remote-testsvn)\.exe$/) {
         my $uuid_vcs_svn_lib = $$build_structure{"LIBS_vcs-svn/lib_GUID"};
         print F << "EOM";
-    <ProjectReference Include="$cdup\\vcs-svn\\lib\\vcs-svn_lib.vcxproj">
+    <ProjectReference Include="$cdup\\vcs-svn\\lib.proj\\vcs-svn_lib.vcxproj">
       <Project>$uuid_vcs_svn_lib</Project>
       <ReferenceOutputAssembly>false</ReferenceOutputAssembly>
     </ProjectReference>
@@ -338,7 +340,7 @@ sub createGlueProject {
 	my $vcxproj = $build_structure{"APPS_${appname}_VCXPROJ"};
 	$vcxproj =~ s/\//\\/g;
         $appname =~ s/.*\///;
-        print F "\"${appname}\", \"${vcxproj}\", \"${uuid}\"";
+        print F "\"${appname}.proj\", \"${vcxproj}\", \"${uuid}\"";
         print F "$SLN_POST";
     }
     foreach (@libs) {
@@ -348,7 +350,7 @@ sub createGlueProject {
         my $vcxproj = $build_structure{"LIBS_${libname}_VCXPROJ"};
 	$vcxproj =~ s/\//\\/g;
         $libname =~ s/\//_/g;
-        print F "\"${libname}\", \"${vcxproj}\", \"${uuid}\"";
+        print F "\"${libname}.proj\", \"${vcxproj}\", \"${uuid}\"";
         print F "$SLN_POST";
     }