Push the NATIVE_CRLF Makefile variable to C and added a test for native.

Commit 95f31e9a correctly points out that the NATIVE_CRLF setting is
incorrectly set on Mingw git. However, the Makefile variable is not
propagated to the C preprocessor and results in no change. This patch
pushes the definition to the C code and adds a test to validate that
when core.eol as native is crlf, we actually normalize text files to this
line ending convention when core.autocrlf is false.

Signed-off-by: Pat Thoyts <patthoyts@users.sourceforge.net>

Makefile

@@ -1480,6 +1480,9 @@ ifdef NO_REGEX
 	COMPAT_CFLAGS += -Icompat/regex
 	COMPAT_OBJS += compat/regex/regex.o
 endif
+ifdef NATIVE_CRLF
+	BASIC_CFLAGS += -DNATIVE_CRLF
+endif
 
 ifdef USE_NED_ALLOCATOR
        COMPAT_CFLAGS += -Icompat/nedmalloc

t/t0026-eol-config.sh

@@ -8,6 +8,20 @@ has_cr() {
 	tr '\015' Q <"$1" | grep Q >/dev/null
 }
 
+# core.eol crlf and core.autocrlf input are not permitted.
+# this lets us check for the core.eol native being crlf.
+set_native_eol_prereq() {
+	rm -rf eol && mkdir eol &&
+	( cd eol &&
+	git init --quiet &&
+	git config core.autocrlf input &&
+	git config core.eol native &&
+	git var core.eol 2> /dev/null
+	) ||
+	test_set_prereq NATIVE_EOL_IS_CRLF
+}
+set_native_eol_prereq
+
 test_expect_success setup '
 
 	git config core.autocrlf false &&
@@ -80,4 +94,22 @@ test_expect_success 'autocrlf=true overrides unset eol' '
 	test -z "$onediff" -a -z "$twodiff"
 '
 
+test_expect_success NATIVE_EOL_IS_CRLF 'eol native is crlf' '
+
+	rm -rf native_eol && mkdir native_eol &&
+	( cd native_eol &&
+	printf "*.txt text\n" > .gitattributes
+	printf "one\r\ntwo\r\nthree\r\n" > filedos.txt
+	printf "one\ntwo\nthree\n" > fileunix.txt
+	git init &&
+	git config core.autocrlf false &&
+	git config core.eol native &&
+	git add filedos.txt fileunix.txt &&
+	git commit -m "first" &&
+	rm file*.txt &&
+	git reset --hard HEAD &&
+	has_cr filedos.txt && has_cr fileunix.txt
+	)
+'
+
 test_done