Fix Issue 15391 - Add possibility to specify custom path to TZDatabas…

…eDir

posix.mak

@@ -22,6 +22,9 @@
 #
 # make std/somemodule.test => only builds and unittests std.somemodule
 #
+# make TZ_DATABASE_DIR=path to the TZDatabase directory => This is useful to
+# overwrite the hardcoded path to the TZDatabase directory needed
+# for std/datetime/timezone.d
 
 ################################################################################
 # Configurable stuff, usually from the command line
@@ -139,6 +142,11 @@ endif
 ifdef ENABLE_COVERAGE
 DFLAGS  += -cov
 endif
+ifneq (,$(TZ_DATABASE_DIR))
+$(file > /tmp/TZDatabaseDirFile, ${TZ_DATABASE_DIR})
+DFLAGS += -version=TZDatabaseDir -J/tmp/
+endif
+
 UDFLAGS=-unittest -version=StdUnittest
 
 # Set DOTOBJ and DOTEXE

std/datetime/timezone.d

@@ -1967,7 +1967,16 @@ public:
     }
 
 
-    version(Android)
+    version(TZDatabaseDir)
+    {
+        import std.string : strip;
+        /++
+            The default directory where the TZ Database files are. It's empty
+            for Windows, since Windows doesn't have them.
+          +/
+        enum defaultTZDatabaseDir = strip(import("TZDatabaseDirFile"));
+    }
+    else version(Android)
     {
         // Android concatenates all time zone data into a single file and stores it here.
         enum defaultTZDatabaseDir = "/system/usr/share/zoneinfo/";