fscache: add GIT_TEST_FSCACHE support

Add support to fscache to enable running the entire test suite with the
fscache enabled.

Signed-off-by: Ben Peart <benpeart@microsoft.com>

compat/win32/fscache.c

@@ -5,6 +5,7 @@
 #include "../../dir.h"
 #include "../../abspath.h"
 #include "../../trace.h"
+#include "config.h"
 
 static int initialized;
 static volatile long enabled;
@@ -401,7 +402,11 @@ int fscache_enable(int enable)
 	int result;
 
 	if (!initialized) {
+		int fscache = git_env_bool("GIT_TEST_FSCACHE", -1);
+
 		/* allow the cache to be disabled entirely */
+		if (fscache != -1)
+			core_fscache = fscache;
 		if (!core_fscache)
 			return 0;
 

t/README

@@ -512,6 +512,9 @@ a test and then fails then the whole test run will abort. This can help to make
 sure the expected tests are executed and not silently skipped when their
 dependency breaks or is simply not present in a new environment.
 
+GIT_TEST_FSCACHE=<boolean> exercises the uncommon fscache code path
+which adds a cache below mingw's lstat and dirent implementations.
+
 Naming Tests
 ------------