Merge branch 'wc/diff'

* wc/diff:
  Test interaction between diff --check and --exit-code
  Use shorter error messages for whitespace problems
  Add tests for "git diff --check" with core.whitespace options
  Make "diff --check" output match "git apply"
  Unify whitespace checking
  diff --check: minor fixups
  "diff --check" should affect exit status

2 files changed, 216 insertions, 2 deletions

diff --git a/t/t4015-diff-whitespace.sh b/t/t4015-diff-whitespace.sh
index 6adf9d11d..9bff8f5e4 100755
--- a/t/t4015-diff-whitespace.sh
+++ b/t/t4015-diff-whitespace.sh
@@ -117,12 +117,197 @@ EOF
 git diff -b > out
 test_expect_success 'another test, with -b' 'git diff expect out'
 
-
 test_expect_success 'check mixed spaces and tabs in indent' '
 
 	# This is indented with SP HT SP.
 	echo " 	 foo();" > x &&
-	git diff --check | grep "space before tab"
+	git diff --check | grep "space before tab in indent"
+
+'
+
+test_expect_success 'check with no whitespace errors' '
+
+	git commit -m "snapshot" &&
+	echo "foo();" > x &&
+	git diff --check
+
+'
+
+test_expect_success 'check with trailing whitespace' '
+
+	echo "foo(); " > x &&
+	! git diff --check
+
+'
+
+test_expect_success 'check with space before tab in indent' '
+
+	# indent has space followed by hard tab
+	echo " 	foo();" > x &&
+	! git diff --check
+
+'
+
+test_expect_success '--check and --exit-code are not exclusive' '
+
+	git checkout x &&
+	git diff --check --exit-code
+
+'
+
+test_expect_success '--check and --quiet are not exclusive' '
+
+	git diff --check --quiet
+
+'
+
+test_expect_success 'check staged with no whitespace errors' '
+
+	echo "foo();" > x &&
+	git add x &&
+	git diff --cached --check
+
+'
+
+test_expect_success 'check staged with trailing whitespace' '
+
+	echo "foo(); " > x &&
+	git add x &&
+	! git diff --cached --check
+
+'
+
+test_expect_success 'check staged with space before tab in indent' '
+
+	# indent has space followed by hard tab
+	echo " 	foo();" > x &&
+	git add x &&
+	! git diff --cached --check
+
+'
+
+test_expect_success 'check with no whitespace errors (diff-index)' '
+
+	echo "foo();" > x &&
+	git add x &&
+	git diff-index --check HEAD
+
+'
+
+test_expect_success 'check with trailing whitespace (diff-index)' '
+
+	echo "foo(); " > x &&
+	git add x &&
+	! git diff-index --check HEAD
+
+'
+
+test_expect_success 'check with space before tab in indent (diff-index)' '
+
+	# indent has space followed by hard tab
+	echo " 	foo();" > x &&
+	git add x &&
+	! git diff-index --check HEAD
+
+'
+
+test_expect_success 'check staged with no whitespace errors (diff-index)' '
+
+	echo "foo();" > x &&
+	git add x &&
+	git diff-index --cached --check HEAD
+
+'
+
+test_expect_success 'check staged with trailing whitespace (diff-index)' '
+
+	echo "foo(); " > x &&
+	git add x &&
+	! git diff-index --cached --check HEAD
+
+'
+
+test_expect_success 'check staged with space before tab in indent (diff-index)' '
+
+	# indent has space followed by hard tab
+	echo " 	foo();" > x &&
+	git add x &&
+	! git diff-index --cached --check HEAD
+
+'
+
+test_expect_success 'check with no whitespace errors (diff-tree)' '
+
+	echo "foo();" > x &&
+	git commit -m "new commit" x &&
+	git diff-tree --check HEAD^ HEAD
+
+'
+
+test_expect_success 'check with trailing whitespace (diff-tree)' '
+
+	echo "foo(); " > x &&
+	git commit -m "another commit" x &&
+	! git diff-tree --check HEAD^ HEAD
+
+'
+
+test_expect_success 'check with space before tab in indent (diff-tree)' '
+
+	# indent has space followed by hard tab
+	echo " 	foo();" > x &&
+	git commit -m "yet another" x &&
+	! git diff-tree --check HEAD^ HEAD
+
+'
+
+test_expect_success 'check trailing whitespace (trailing-space: off)' '
+
+	git config core.whitespace "-trailing-space" &&
+	echo "foo ();   " > x &&
+	git diff --check
+
+'
+
+test_expect_success 'check trailing whitespace (trailing-space: on)' '
+
+	git config core.whitespace "trailing-space" &&
+	echo "foo ();   " > x &&
+	! git diff --check
+
+'
+
+test_expect_success 'check space before tab in indent (space-before-tab: off)' '
+
+	# indent contains space followed by HT
+	git config core.whitespace "-space-before-tab" &&
+	echo " 	foo ();" > x &&
+	git diff --check
+
+'
+
+test_expect_success 'check space before tab in indent (space-before-tab: on)' '
+
+	# indent contains space followed by HT
+	git config core.whitespace "space-before-tab" &&
+	echo " 	foo ();   " > x &&
+	! git diff --check
+
+'
+
+test_expect_success 'check spaces as indentation (indent-with-non-tab: off)' '
+
+	git config core.whitespace "-indent-with-non-tab"
+	echo "                foo ();" > x &&
+	git diff --check
+
+'
+
+test_expect_success 'check spaces as indentation (indent-with-non-tab: on)' '
+
+	git config core.whitespace "indent-with-non-tab" &&
+	echo "                foo ();" > x &&
+	! git diff --check
 
 '
 
diff --git a/t/t4017-diff-retval.sh b/t/t4017-diff-retval.sh
index 68731908b..dc0b7126c 100755
--- a/t/t4017-diff-retval.sh
+++ b/t/t4017-diff-retval.sh
@@ -76,4 +76,33 @@ test_expect_success 'git diff-index --cached HEAD' '
 	}
 '
 
+test_expect_success '--check --exit-code returns 0 for no difference' '
+
+	git diff --check --exit-code
+
+'
+
+test_expect_success '--check --exit-code returns 1 for a clean difference' '
+
+	echo "good" > a &&
+	git diff --check --exit-code
+	test $? = 1
+
+'
+
+test_expect_success '--check --exit-code returns 3 for a dirty difference' '
+
+	echo "bad   " >> a &&
+	git diff --check --exit-code
+	test $? = 3
+
+'
+
+test_expect_success '--check with --no-pager returns 2 for dirty difference' '
+
+	git --no-pager diff --check
+	test $? = 2
+
+'
+
 test_done