lang/mono*: add compat symlink for devel/msbuild < 16

/usr/local/lib/mono/msbuild/15.0/bin/Microsoft.CSharp.CurrentVersion.targets(331,5): error MSB4019: The imported project "/usr/local/lib/mono/msbuild/15.0/bin/Roslyn/Microsoft.CSharp.Core.targets" was not found. Confirm that the path in the <Import> declaration is correct, and that the file exists on disk.

PR:		256342
Suggested by:	Marcin Cieślak
Regressed by:	mono/mono@1717687e16dd

emulators/mesen/Makefile

@@ -50,8 +50,8 @@ LIBRETRO_ALL_TARGET=	libretro
 
 .include <bsd.port.pre.mk>
 
-.if defined(MONO_DEFAULT) && ${MONO_DEFAULT} > 5.10
-BROKEN=		fails to build with Mono version ${MONO_DEFAULT}: The imported project "/usr/local/lib/mono/msbuild/15.0/bin/Roslyn/Microsoft.CSharp.Core.targets" was not found
+.if defined(MONO_DEFAULT) && ${MONO_DEFAULT} > 6
+BROKEN=		fails to build with Mono version ${MONO_DEFAULT}: error MSB4184: The expression ""Program.cs".GetPathsOfAllDirectoriesAbove()" cannot be evaluated. Method 'System.String.GetPathsOfAllDirectoriesAbove' not found.
 .endif
 
 do-install: 	# empty to avoid default

games/openbve/Makefile

@@ -53,8 +53,8 @@ OPTIONS_DEFINE=	DOCS
 
 .include <bsd.port.pre.mk>
 
-.if defined(MONO_DEFAULT) && ${MONO_DEFAULT} > 5.10
-BROKEN=		fails to build with Mono version ${MONO_DEFAULT}: The imported project "/usr/local/lib/mono/msbuild/15.0/bin/Roslyn/Microsoft.CSharp.Core.targets" was not found
+.if defined(MONO_DEFAULT) && ${MONO_DEFAULT} > 6
+BROKEN=		fails to build with Mono version ${MONO_DEFAULT}: error MSB4184: The expression ""Program.cs".GetPathsOfAllDirectoriesAbove()" cannot be evaluated. Method 'System.String.GetPathsOfAllDirectoriesAbove' not found.
 .endif
 
 post-patch:

games/openra/Makefile

@@ -57,8 +57,8 @@ PORTDATA=	*
 
 .include <bsd.port.pre.mk>
 
-.if defined(MONO_DEFAULT) && ${MONO_DEFAULT} > 5.10
-BROKEN=		fails to build with Mono version ${MONO_DEFAULT}: The imported project "/usr/local/lib/mono/msbuild/15.0/bin/Roslyn/Microsoft.CSharp.Core.targets" was not found
+.if defined(MONO_DEFAULT) && ${MONO_DEFAULT} > 6
+BROKEN=		fails to build with Mono version ${MONO_DEFAULT}: error MSB4184: The expression ""Program.cs".GetPathsOfAllDirectoriesAbove()" cannot be evaluated. Method 'System.String.GetPathsOfAllDirectoriesAbove' not found.
 .endif
 
 post-extract:

lang/fsharp/Makefile

@@ -32,12 +32,8 @@ do-test:
 
 .include <bsd.port.pre.mk>
 
-.if defined(MONO_DEFAULT)
-.if ${MONO_DEFAULT} > 6
+.if defined(MONO_DEFAULT) && ${MONO_DEFAULT} > 6
 BROKEN=		fails to build with Mono version ${MONO_DEFAULT}: A unique overload for method 'GetFileNameWithoutExtension' could not be determined based on type information prior to this program point
-.elif ${MONO_DEFAULT} > 5.10
-BROKEN=		fails to build with Mono version ${MONO_DEFAULT}: The type 'HashSet' is not defined
-.endif
 .endif
 
 .include <bsd.port.post.mk>

lang/mono5.20/Makefile

@@ -1,6 +1,6 @@
 PORTNAME=	mono
 PORTVERSION=	5.20.1.34
-PORTREVISION=	1
+PORTREVISION=	2
 CATEGORIES=	lang
 MASTER_SITES=	https://download.mono-project.com/sources/mono/
 PKGNAMESUFFIX=	5.20
@@ -108,5 +108,9 @@ post-configure:
 
 post-install:
 	${MKDIR} ${STAGEDIR}${PREFIX}/mono
+# XXX Drop after devel/msbuild >= 16.0 per https://github.com/mono/msbuild/commit/48f3571f4036
+	${RLN} ${STAGEDIR}${PREFIX}/lib/mono/msbuild/Current \
+		${STAGEDIR}${PREFIX}/lib/mono/msbuild/15.0
+	${ECHO_CMD} lib/mono/msbuild/15.0 >>${TMPPLIST}
 
 .include <bsd.port.post.mk>

lang/mono6.8/Makefile

@@ -1,6 +1,6 @@
 PORTNAME=	mono
 PORTVERSION=	6.8.0.123
-PORTREVISION=	1
+PORTREVISION=	2
 CATEGORIES=	lang
 MASTER_SITES=	https://download.mono-project.com/sources/mono/
 PKGNAMESUFFIX=	6.8
@@ -118,5 +118,9 @@ post-patch:
 
 post-install:
 	${MKDIR} ${STAGEDIR}${PREFIX}/mono
+# XXX Drop after devel/msbuild >= 16.0 per https://github.com/mono/msbuild/commit/48f3571f4036
+	${RLN} ${STAGEDIR}${PREFIX}/lib/mono/msbuild/Current \
+		${STAGEDIR}${PREFIX}/lib/mono/msbuild/15.0
+	${ECHO_CMD} lib/mono/msbuild/15.0 >>${TMPPLIST}
 
 .include <bsd.port.post.mk>