refs: ref entry with NULL sha1 is can be a dangling symref

diff --git a/t/t0000-basic.sh b/t/t0000-basic.sh
index 70df15cbd8339b552a56a95ca0c0893138550201..f4ca4fc85c6b52a2ba919528284f2b668e6bd3d2 100755 (executable)
--- a/t/t0000-basic.sh
+++ b/t/t0000-basic.sh
@@ -57,6 +57,21 @@ test_expect_failure 'pretend we have a known breakage' '
 test_expect_failure 'pretend we have fixed a known breakage' '
     :
 '
+test_set_prereq HAVEIT
+haveit=no
+test_expect_success HAVEIT 'test runs if prerequisite is satisfied' '
+    test_have_prereq HAVEIT &&
+    haveit=yes
+'
+donthaveit=yes
+test_expect_success DONTHAVEIT 'unmet prerequisite causes test to be skipped' '
+    donthaveit=no
+'
+if test $haveit$donthaveit != yesyes
+then
+       say "bug in test framework: prerequisite tags do not work reliably"
+       exit 1
+fi
 
 ################################################################
 # Basics of the basics
@@ -100,12 +115,31 @@ test_expect_success \
     'test "$tree" = 4b825dc642cb6eb9a060e54bf8d69288fbee4904'
 
 # Various types of objects
+# Some filesystems do not support symblic links; on such systems
+# some expected values are different
 mkdir path2 path3 path3/subp3
-for p in path0 path2/file2 path3/file3 path3/subp3/file3
+paths='path0 path2/file2 path3/file3 path3/subp3/file3'
+for p in $paths
 do
     echo "hello $p" >$p
-    ln -s "hello $p" ${p}sym
 done
+if test_have_prereq SYMLINKS
+then
+       for p in $paths
+       do
+               ln -s "hello $p" ${p}sym
+       done
+       expectfilter=cat
+       expectedtree=087704a96baf1c2d1c869a8b084481e121c88b5b
+       expectedptree1=21ae8269cacbe57ae09138dcc3a2887f904d02b3
+       expectedptree2=3c5e5399f3a333eddecce7a9b9465b63f65f51e2
+else
+       expectfilter='grep -v sym'
+       expectedtree=8e18edf7d7edcf4371a3ac6ae5f07c2641db7c46
+       expectedptree1=cfb8591b2f65de8b8cc1020cd7d9e67e7793b325
+       expectedptree2=ce580448f0148b985a513b693fdf7d802cacb44f
+fi
+
 test_expect_success \
     'adding various types of objects with git update-index --add.' \
     'find path* ! -type d -print | xargs git update-index --add'
@@ -115,7 +149,7 @@ test_expect_success \
     'showing stage with git ls-files --stage' \
     'git ls-files --stage >current'
 
-cat >expected <<\EOF
+$expectfilter >expected <<\EOF
 100644 f87290f8eb2cbbea7857214459a0739927eab154 0      path0
 120000 15a98433ae33114b085f3eb3bb03b832b3180a01 0      path0sym
 100644 3feff949ed00a62d9f7af97c15cd8a30595e7ac7 0      path2/file2
@@ -127,14 +161,14 @@ cat >expected <<\EOF
 EOF
 test_expect_success \
     'validate git ls-files output for a known tree.' \
-    'diff current expected'
+    'test_cmp expected current'
 
 test_expect_success \
     'writing tree out with git write-tree.' \
     'tree=$(git write-tree)'
 test_expect_success \
     'validate object ID for a known tree.' \
-    'test "$tree" = 087704a96baf1c2d1c869a8b084481e121c88b5b'
+    'test "$tree" = "$expectedtree"'
 
 test_expect_success \
     'showing tree with git ls-tree' \
@@ -145,16 +179,16 @@ cat >expected <<\EOF
 040000 tree 58a09c23e2ca152193f2786e06986b7b6712bdbe   path2
 040000 tree 21ae8269cacbe57ae09138dcc3a2887f904d02b3   path3
 EOF
-test_expect_success \
+test_expect_success SYMLINKS \
     'git ls-tree output for a known tree.' \
-    'diff current expected'
+    'test_cmp expected current'
 
 # This changed in ls-tree pathspec change -- recursive does
 # not show tree nodes anymore.
 test_expect_success \
     'showing tree with git ls-tree -r' \
     'git ls-tree -r $tree >current'
-cat >expected <<\EOF
+$expectfilter >expected <<\EOF
 100644 blob f87290f8eb2cbbea7857214459a0739927eab154   path0
 120000 blob 15a98433ae33114b085f3eb3bb03b832b3180a01   path0sym
 100644 blob 3feff949ed00a62d9f7af97c15cd8a30595e7ac7   path2/file2
@@ -166,7 +200,7 @@ cat >expected <<\EOF
 EOF
 test_expect_success \
     'git ls-tree -r output for a known tree.' \
-    'diff current expected'
+    'test_cmp expected current'
 
 # But with -r -t we can have both.
 test_expect_success \
@@ -185,23 +219,23 @@ cat >expected <<\EOF
 100644 blob 00fb5908cb97c2564a9783c0c64087333b3b464f   path3/subp3/file3
 120000 blob 6649a1ebe9e9f1c553b66f5a6e74136a07ccc57c   path3/subp3/file3sym
 EOF
-test_expect_success \
+test_expect_success SYMLINKS \
     'git ls-tree -r output for a known tree.' \
-    'diff current expected'
+    'test_cmp expected current'
 
 test_expect_success \
     'writing partial tree out with git write-tree --prefix.' \
     'ptree=$(git write-tree --prefix=path3)'
 test_expect_success \
     'validate object ID for a known tree.' \
-    'test "$ptree" = 21ae8269cacbe57ae09138dcc3a2887f904d02b3'
+    'test "$ptree" = "$expectedptree1"'
 
 test_expect_success \
     'writing partial tree out with git write-tree --prefix.' \
     'ptree=$(git write-tree --prefix=path3/subp3)'
 test_expect_success \
     'validate object ID for a known tree.' \
-    'test "$ptree" = 3c5e5399f3a333eddecce7a9b9465b63f65f51e2'
+    'test "$ptree" = "$expectedptree2"'
 
 cat >badobjects <<EOF
 100644 blob 1000000000000000000000000000000000000000   dir/file1
@@ -234,7 +268,7 @@ test_expect_success \
      newtree=$(git write-tree) &&
      test "$newtree" = "$tree"'
 
-cat >expected <<\EOF
+$expectfilter >expected <<\EOF
 :100644 100644 f87290f8eb2cbbea7857214459a0739927eab154 0000000000000000000000000000000000000000 M     path0
 :120000 120000 15a98433ae33114b085f3eb3bb03b832b3180a01 0000000000000000000000000000000000000000 M     path0sym
 :100644 100644 3feff949ed00a62d9f7af97c15cd8a30595e7ac7 0000000000000000000000000000000000000000 M     path2/file2
@@ -257,7 +291,7 @@ test_expect_success \
     'git diff-files >current && cmp -s current /dev/null'
 
 ################################################################
-P=087704a96baf1c2d1c869a8b084481e121c88b5b
+P=$expectedtree
 test_expect_success \
     'git commit-tree records the correct tree in a commit.' \
     'commit0=$(echo NO | git commit-tree $P) &&
@@ -293,7 +327,7 @@ test_expect_success 'update-index D/F conflict' '
        test $numpath0 = 1
 '
 
-test_expect_success 'absolute path works as expected' '
+test_expect_success SYMLINKS 'absolute path works as expected' '
        mkdir first &&
        ln -s ../.git first/.git &&
        mkdir second &&